Release 2.0.0 (#1680)

* update release notes
* bump version
* change the default alignment in patronictl table output to `left`
* add missing tests
* add missing pieces to the documentation

.travis.yml

@@ -7,20 +7,23 @@ addons:
       - expect-dev # for unbuffer
 env:
   global:
-  - ETCDVERSION=3.0.17 ZKVERSION=3.4.11 CONSULVERSION=0.7.4
+  - ETCDVERSION=3.3.13 ZKVERSION=3.4.14 CONSULVERSION=0.7.4
-  - PYVERSIONS="2.7 3.5 3.6"
+  - PYVERSIONS="2.7 3.6"
-  - EXCLUDE_BEHAVE="3.5"
   - BOTO_CONFIG=/doesnotexist
 matrix:
   include:
   - python: "3.5"
-    env: TEST_SUITE="python setup.py"
+    env: PYVERSIONS="2.7 3.5 3.6" TEST_SUITE="python setup.py"
   - python: "3.6"
     env: DCS="etcd" TEST_SUITE="behave"
+  - python: "3.6"
+    env: DCS="etcd3" TEST_SUITE="behave"
   - python: "3.6"
     env: DCS="exhibitor" TEST_SUITE="behave"
   - python: "3.6"
     env: DCS="consul" TEST_SUITE="behave"
+  - python: "3.6"
+    env: DCS="raft" TEST_SUITE="behave"
   - python: "3.6"
     env: DCS="kubernetes" TEST_SUITE="behave"
 branches:
@@ -34,10 +37,8 @@ before_cache:
 - |
   rm -fr $HOME/mycache/python*
   for pv in $PYVERSIONS; do
-      if [[ $TEST_SUITE != "behave" || $pv != $EXCLUDE_BEHAVE ]]; then
       fpv=$(basename $(readlink $HOME/virtualenv/python${pv}))
       mv $HOME/virtualenv/${fpv} $HOME/mycache/${fpv}
-      fi
   done
 install:
   - |
@@ -58,6 +59,7 @@ install:
         function get_etcd() {
             EC=~/mycache/etcd_${ETCDVERSION}
             if [[ ! -x $EC ]]; then
+                rm -rf ~/mycache/etcd_*
                 curl -L https://github.com/coreos/etcd/releases/download/v${ETCDVERSION}/etcd-v${ETCDVERSION}-linux-amd64.tar.gz \
                     | tar xz -C . --strip=1 --wildcards --no-anchored etcd
                 [[ ${PIPESTATUS[0]} == 0 ]] || return 1
@@ -66,6 +68,10 @@ install:
             ln -s $EC etcd
         }
 
+        function get_etcd3() {
+            get_etcd
+        }
+
         function get_kubernetes() {
             wget -O localkube "https://storage.googleapis.com/minikube/k8sReleases/v1.7.0/localkube-linux-amd64"
             chmod +x localkube
@@ -102,6 +108,10 @@ install:
             done&
         }
 
+        function get_raft() {
+            return 0
+        }
+
         attempt_num=1
         until get_${DCS}; do
             [[ $attempt_num -ge 3 ]] && exit 1
@@ -111,7 +121,6 @@ install:
     fi
 
     for pv in $PYVERSIONS; do
-        if [[ $TEST_SUITE != "behave" || $pv != $EXCLUDE_BEHAVE ]]; then
         fpv=$(basename $(readlink $HOME/virtualenv/python$pv))
         if [[ -d ~/mycache/${fpv} ]]; then
             mv ~/virtualenv/${fpv} ~/virtualenv/${fpv}.bckp
@@ -122,30 +131,28 @@ install:
         for p in '-r requirements.txt' 'psycopg2-binary behave codacy-coverage coverage coveralls flake8 mock pytest-cov pytest setuptools'; do
             pip install $p --upgrade
         done
-        fi
     done
 script:
   - |
     for pv in $PYVERSIONS; do
-        if [[ $TEST_SUITE == "behave" && $pv == $EXCLUDE_BEHAVE ]]; then
-            continue
-        fi
-
         source ~/virtualenv/python${pv}/bin/activate
 
-        if [[ $TEST_SUITE != "behave" ]]; then
+        if [[ $TEST_SUITE = "behave" ]]; then
-            echo Running unit tests using python${pv}
+            echo Running integration tests using python${pv}
-            unbuffer $TEST_SUITE test
-            $TEST_SUITE flake8
-        elif [[ $pv != $EXCLUDE_BEHAVE ]]; then
-            echo Running acceptance tests using python${pv}
             if ! PATH=.:/usr/lib/postgresql/9.6/bin:$PATH unbuffer $TEST_SUITE; then
                 # output all log files when tests are failing
                 grep . features/output/*_failed/*postgres?.*
                 exit 1
             fi
+        else
+            echo Running unit tests using python${pv}
+            unbuffer $TEST_SUITE test
+            $TEST_SUITE flake8
         fi
+        mv .coverage /tmp/.coverage.$pv
     done
+    mv /tmp/.coverage.* .
+    python -m coverage combine
 
     set +e
 after_success:

Dockerfile

@@ -14,7 +14,7 @@ ARG PGDATA
 ARG LC_ALL
 ARG LANG
 
-ENV ETCDVERSION=2.3.8 CONFDVERSION=0.16.0
+ENV ETCDVERSION=3.3.13 CONFDVERSION=0.16.0
 
 RUN set -ex \
     && export DEBIAN_FRONTEND=noninteractive \
@@ -25,11 +25,12 @@ RUN set -ex \
             | grep -Ev '^python3-(sphinx|etcd|consul|kazoo|kubernetes)' \
             | xargs apt-get install -y vim curl less jq locales haproxy sudo \
                             python3-etcd python3-kazoo python3-pip busybox \
+                            net-tools iputils-ping --fix-missing \
     && pip3 install dumb-init \
 \
     # Cleanup all locales but en_US.UTF-8
     && find /usr/share/i18n/charmaps/ -type f ! -name UTF-8.gz -delete \
-    && find /usr/share/i18n/locales/ -type f ! -name en_US ! -name en_GB ! -name i18n ! -name iso14651_t1 ! -name iso14651_t1_common ! -name 'translit_*' -delete \
+    && find /usr/share/i18n/locales/ -type f ! -name en_US ! -name en_GB ! -name i18n* ! -name iso14651_t1 ! -name iso14651_t1_common ! -name 'translit_*' -delete \
     && echo 'en_US.UTF-8 UTF-8' > /usr/share/i18n/SUPPORTED \
 \
     # Make sure we have a en_US.UTF-8 locale available
@@ -149,6 +150,7 @@ RUN sed -i 's/env python/&3/' /patroni*.py \
     && sed -i 's/^    \(replication\|superuser\|rewind\|unix_socket_directories\|\(\(  \)\{0,1\}\(username\|password\)\)\):/#&/' postgres?.yml \
     && sed -i 's/^      parameters:/      pg_hba:\n      - local all all trust\n      - host replication all all md5\n      - host all all all md5\n&\n        max_connections: 100/'  postgres?.yml \
     && if [ "$COMPRESS" = "true" ]; then chmod u+s /usr/bin/sudo; fi \
+    && chmod +s /bin/ping \
     && chown -R postgres:postgres $PGHOME /run /etc/haproxy
 
 USER postgres

README.rst

@@ -96,7 +96,7 @@ Patroni can be installed with pip:
 
 where dependencies can be either empty, or consist of one or more of the following:
 
-etcd
+etcd or etcd3
     `python-etcd` module in order to use Etcd as DCS
 consul
     `python-consul` module in order to use Consul as DCS
@@ -106,6 +106,8 @@ exhibitor
     `kazoo` module in order to use Exhibitor as DCS (same dependencies as for Zookeeper)
 kubernetes
     `kubernetes` module in order to use Kubernetes as DCS in Patroni
+raft
+    `pysyncobj` module in order to use python Raft implementation as DCS
 aws
     `boto` in order to use AWS callbacks
 
@@ -124,7 +126,7 @@ Running and Configuring
 To get started, do the following from different terminals:
 ::
 
-    > etcd --data-dir=data/etcd
+    > etcd --data-dir=data/etcd --enable-v2=true
     > ./patroni.py postgres0.yml
     > ./patroni.py postgres1.yml
 

docker-compose.yml

@@ -6,57 +6,31 @@ networks:
     demo:
 
 services:
-    etcd1:
+    etcd1: &etcd
         image: patroni
         networks: [ demo ]
-        env_file: docker/etcd.env
+        environment:
+            ETCD_LISTEN_PEER_URLS: http://0.0.0.0:2380
+            ETCD_LISTEN_CLIENT_URLS: http://0.0.0.0:2379
+            ETCD_INITIAL_CLUSTER: etcd1=http://etcd1:2380,etcd2=http://etcd2:2380,etcd3=http://etcd3:2380
+            ETCD_INITIAL_CLUSTER_STATE: new
+            ETCD_INITIAL_CLUSTER_TOKEN: tutorial
         container_name: demo-etcd1
         hostname: etcd1
         command: etcd -name etcd1 -initial-advertise-peer-urls http://etcd1:2380
 
     etcd2:
-        image: patroni
+        <<: *etcd
-        networks: [ demo ]
-        env_file: docker/etcd.env
         container_name: demo-etcd2
         hostname: etcd2
         command: etcd -name etcd2 -initial-advertise-peer-urls http://etcd2:2380
 
     etcd3:
-        image: patroni
+        <<: *etcd
-        networks: [ demo ]
-        env_file: docker/etcd.env
         container_name: demo-etcd3
         hostname: etcd3
         command: etcd -name etcd3 -initial-advertise-peer-urls http://etcd3:2380
 
-    patroni1:
-        image: patroni
-        networks: [ demo ]
-        env_file: docker/patroni.env
-        hostname: patroni1
-        container_name: demo-patroni1
-        environment:
-            PATRONI_NAME: patroni1
-
-    patroni2:
-        image: patroni
-        networks: [ demo ]
-        env_file: docker/patroni.env
-        hostname: patroni2
-        container_name: demo-patroni2
-        environment:
-            PATRONI_NAME: patroni2
-
-    patroni3:
-        image: patroni
-        networks: [ demo ]
-        env_file: docker/patroni.env
-        hostname: patroni3
-        container_name: demo-patroni3
-        environment:
-            PATRONI_NAME: patroni3
-
     haproxy:
         image: patroni
         networks: [ demo ]
@@ -67,3 +41,37 @@ services:
             - "5000:5000"
             - "5001:5001"
         command: haproxy
+        environment: &haproxy_env
+            ETCDCTL_ENDPOINTS: http://etcd1:2379,http://etcd2:2379,http://etcd3:2379
+            PATRONI_ETCD3_HOSTS: "'etcd1:2379','etcd2:2379','etcd3:2379'"
+            PATRONI_SCOPE: demo
+
+    patroni1:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/patroni.env
+        hostname: patroni1
+        container_name: demo-patroni1
+        environment:
+            <<: *haproxy_env
+            PATRONI_NAME: patroni1
+
+    patroni2:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/patroni.env
+        hostname: patroni2
+        container_name: demo-patroni2
+        environment:
+            <<: *haproxy_env
+            PATRONI_NAME: patroni2
+
+    patroni3:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/patroni.env
+        hostname: patroni3
+        container_name: demo-patroni3
+        environment:
+            <<: *haproxy_env
+            PATRONI_NAME: patroni3

docker/entrypoint.sh

@@ -25,7 +25,7 @@ case "$1" in
             while ! etcdctl cluster-health 2> /dev/null; do
                 sleep 1
             done
-            exec dumb-init $CONFD etcd -node $(echo $ETCDCTL_ENDPOINTS | sed 's/,/ -node /g')
+            exec dumb-init $CONFD etcdv3 -node $(echo $ETCDCTL_ENDPOINTS | sed 's/,/ -node /g')
         fi
         ;;
     etcd)
@@ -37,7 +37,7 @@ case "$1" in
 esac
 
 ## We start an etcd
-if [ -z "$PATRONI_ETCD_HOSTS" ] && [ -z "$PATRONI_ZOOKEEPER_HOSTS" ]; then
+if [ -z "$PATRONI_ETCD3_HOSTS" ] && [ -z "$PATRONI_ZOOKEEPER_HOSTS" ]; then
     export PATRONI_ETCD_URL="http://127.0.0.1:2379"
     etcd --data-dir /tmp/etcd.data -advertise-client-urls=$PATRONI_ETCD_URL -listen-client-urls=http://0.0.0.0:2379 > /var/log/etcd.log 2> /var/log/etcd.err &
 fi

docker/etcd.env

@@ -1,5 +0,0 @@
-ETCD_LISTEN_PEER_URLS=http://0.0.0.0:2380
-ETCD_LISTEN_CLIENT_URLS=http://0.0.0.0:2379
-ETCD_INITIAL_CLUSTER=etcd1=http://etcd1:2380,etcd2=http://etcd2:2380,etcd3=http://etcd3:2380
-ETCD_INITIAL_CLUSTER_STATE=new
-ETCD_INITIAL_CLUSTER_TOKEN=tutorial

docker/patroni.env

@@ -1,6 +1,3 @@
-PATRONI_SCOPE=demo
-PATRONI_ETCD_HOSTS='etcd1:2379','etcd2:2379','etcd3:2379'
-
 PATRONI_RESTAPI_USERNAME=admin
 PATRONI_RESTAPI_PASSWORD=admin
 PATRONI_SUPERUSER_USERNAME=postgres
@@ -9,6 +6,3 @@ PATRONI_REPLICATION_USERNAME=replicator
 PATRONI_REPLICATION_PASSWORD=replicate
 PATRONI_admin_PASSWORD=admin
 PATRONI_admin_OPTIONS=createdb,createrole
-
-# for etcdctl
-ETCDCTL_ENDPOINTS=http://etcd1:2379,http://etcd2:2379,http://etcd3:2379

docs/ENVIRONMENT.rst

@@ -11,7 +11,11 @@ Global/Universal
 -  **PATRONI\_NAME**: name of the node where the current instance of Patroni is running. Must be unique for the cluster.
 -  **PATRONI\_NAMESPACE**: path within the configuration store where Patroni will keep information about the cluster. Default value: "/service"
 -  **PATRONI\_SCOPE**: cluster name
+
+Log
+---
 -  **PATRONI\_LOG\_LEVEL**: sets the general logging level. Default value is **INFO** (see `the docs for Python logging <https://docs.python.org/3.6/library/logging.html#levels>`_)
+-  **PATRONI\_LOG\_TRACEBACK\_LEVEL**: sets the level where tracebacks will be visible. Default value is **ERROR**. Set it to **DEBUG** if you want to see tracebacks only if you enable **PATRONI\_LOG\_LEVEL=DEBUG**.
 -  **PATRONI\_LOG\_FORMAT**: sets the log formatting string. Default value is **%(asctime)s %(levelname)s: %(message)s** (see `the LogRecord attributes <https://docs.python.org/3.6/library/logging.html#logrecord-attributes>`_)
 -  **PATRONI\_LOG\_DATEFORMAT**: sets the datetime formatting string. (see the `formatTime() documentation <https://docs.python.org/3.6/library/logging.html#logging.Formatter.formatTime>`_)
 -  **PATRONI\_LOG\_MAX\_QUEUE\_SIZE**: Patroni is using two-step logging. Log records are written into the in-memory queue and there is a separate thread which pulls them from the queue and writes to stderr or file. The maximum size of the internal queue is limited by default by **1000** records, which is enough to keep logs for the past 1h20m.
@@ -31,8 +35,8 @@ Example: defining ``PATRONI_admin_PASSWORD=strongpasswd`` and ``PATRONI_admin_OP
 
 Consul
 ------
--  **PATRONI\_CONSUL\_HOST**: the host:port for the Consul endpoint.
+-  **PATRONI\_CONSUL\_HOST**: the host:port for the Consul local agent.
--  **PATRONI\_CONSUL\_URL**: url for the Consul, in format: http(s)://host:port
+-  **PATRONI\_CONSUL\_URL**: url for the Consul local agent, in format: http(s)://host:port
 -  **PATRONI\_CONSUL\_PORT**: (optional) Consul port
 -  **PATRONI\_CONSUL\_SCHEME**: (optional) **http** or **https**, defaults to **http**
 -  **PATRONI\_CONSUL\_TOKEN**: (optional) ACL token
@@ -42,7 +46,7 @@ Consul
 -  **PATRONI\_CONSUL\_KEY**: (optional) File with the client key. Can be empty if the key is part of certificate.
 -  **PATRONI\_CONSUL\_DC**: (optional) Datacenter to communicate with. By default the datacenter of the host is used.
 -  **PATRONI\_CONSUL\_CONSISTENCY**: (optional) Select consul consistency mode. Possible values are ``default``, ``consistent``, or ``stale`` (more details in `consul API reference <https://www.consul.io/api/features/consistency.html/>`__)
--  **PATRONI\_CONSUL\_CHECKS**: (optional) list of Consul health checks used for the session. If not specified Consul will use "serfHealth" in additional to the TTL based check created by Patroni. Additional checks, in particular the "serfHealth", may cause the leader lock to expire faster than in `ttl` seconds when the leader instance becomes unavailable.
+-  **PATRONI\_CONSUL\_CHECKS**: (optional) list of Consul health checks used for the session. By default an empty list is used.
 -  **PATRONI\_CONSUL\_REGISTER\_SERVICE**: (optional) whether or not to register a service with the name defined by the scope parameter and the tag master, replica or standby-leader depending on the node's role. Defaults to **false**
 -  **PATRONI\_CONSUL\_SERVICE\_CHECK\_INTERVAL**: (optional) how often to perform health check against registered url
 
@@ -62,6 +66,28 @@ Etcd
 -  **PATRONI\_ETCD\_CERT**: File with the client certificate.
 -  **PATRONI\_ETCD\_KEY**: File with the client key. Can be empty if the key is part of certificate.
 
+Etcdv3
+------
+Environment names for Etcdv3 are similar as for Etcd, you just need to use ``ETCD3`` instead of ``ETCD`` in the variable name. Example: ``PATRONI_ETCD3_HOST``, ``PATRONI_ETCD3_CACERT``, and so on.
+
+.. warning::
+    Keys created with protocol version 2 are not visible with protocol version 3 and the other way around, therefore it is not possible to switch from Etcd to Etcdv3 just by updating Patroni configuration.
+
+
+ZooKeeper
+---------
+-  **PATRONI\_ZOOKEEPER\_HOSTS**: Comma separated list of ZooKeeper cluster members: "'host1:port1','host2:port2','etc...'". It is important to quote every single entity!
+-  **PATRONI\_ZOOKEEPER\_USE\_SSL**: (optional) Whether SSL is used or not. Defaults to ``false``. If set to ``false``, all SSL specific parameters are ignored.
+-  **PATRONI\_ZOOKEEPER\_CACERT**: (optional) The CA certificate. If present it will enable validation.
+-  **PATRONI\_ZOOKEEPER\_CERT**: (optional) File with the client certificate.
+-  **PATRONI\_ZOOKEEPER\_KEY**: (optional) File with the client key.
+-  **PATRONI\_ZOOKEEPER\_KEY\_PASSWORD**: (optional) The client key password.
+-  **PATRONI\_ZOOKEEPER\_VERIFY**: (optional) Whether to verify certificate or not. Defaults to ``true``.
+
+.. note::
+    It is required to install ``kazoo>=2.6.0`` to support SSL.
+
+
 Exhibitor
 ---------
 -  **PATRONI\_EXHIBITOR\_HOSTS**: initial list of Exhibitor (ZooKeeper) nodes in format: 'host1,host2,etc...'. This list updates automatically whenever the Exhibitor (ZooKeeper) cluster topology changes.
@@ -71,13 +97,21 @@ Exhibitor
 
 Kubernetes
 ----------
+-  **PATRONI\_KUBERNETES\_BYPASS\_API\_SERVICE**: (optional) When communicating with the Kubernetes API, Patroni is usually relying on the `kubernetes` service, the address of which is exposed in the pods via the `KUBERNETES_SERVICE_HOST` environment variable. If `PATRONI_KUBERNETES_BYPASS_API_SERVICE` is set to ``true``, Patroni will resolve the list of API nodes behind the service and connect directly to them.
 -  **PATRONI\_KUBERNETES\_NAMESPACE**: (optional) Kubernetes namespace where the Patroni pod is running. Default value is `default`.
 -  **PATRONI\_KUBERNETES\_LABELS**: Labels in format ``{label1: value1, label2: value2}``. These labels will be used to find existing objects (Pods and either Endpoints or ConfigMaps) associated with the current cluster. Also Patroni will set them on every object (Endpoint or ConfigMap) it creates.
 -  **PATRONI\_KUBERNETES\_SCOPE\_LABEL**: (optional) name of the label containing cluster name. Default value is `cluster-name`.
 -  **PATRONI\_KUBERNETES\_ROLE\_LABEL**: (optional) name of the label containing Postgres role (`master` or `replica`). Patroni will set this label on the pod it is running in. Default value is `role`.
 -  **PATRONI\_KUBERNETES\_USE\_ENDPOINTS**: (optional) if set to true, Patroni will use Endpoints instead of ConfigMaps to run leader elections and keep cluster state.
 -  **PATRONI\_KUBERNETES\_POD\_IP**: (optional) IP address of the pod Patroni is running in. This value is required when `PATRONI_KUBERNETES_USE_ENDPOINTS` is enabled and is used to populate the leader endpoint subsets when the pod's PostgreSQL is promoted.
--  **PATRONI\_KUBERNETES\_PORTS**: (optional) if the Service object has the name for the port, the same name must appear in the Endpoint object, otherwise service won't work. For example, if your service is defined as ``{Kind: Service, spec: {ports: [{name: postgresql, port: 5432, targetPort: 5432}]}}``, then you have to set ``PATRONI_KUBERNETES_PORTS='{[{"name": "postgresql", "port": 5432}]}'`` and Patroni will use it for updating subsets of the leader Endpoint. This parameter is used only if `PATRONI_KUBERNETES_USE_ENDPOINTS` is set.
+-  **PATRONI\_KUBERNETES\_PORTS**: (optional) if the Service object has the name for the port, the same name must appear in the Endpoint object, otherwise service won't work. For example, if your service is defined as ``{Kind: Service, spec: {ports: [{name: postgresql, port: 5432, targetPort: 5432}]}}``, then you have to set ``PATRONI_KUBERNETES_PORTS='[{"name": "postgresql", "port": 5432}]'`` and Patroni will use it for updating subsets of the leader Endpoint. This parameter is used only if `PATRONI_KUBERNETES_USE_ENDPOINTS` is set.
+
+Raft
+----
+
+-  **PATRONI\_RAFT\_SELF\_ADDR**: ``ip:port`` to listen on for Raft connections. If not set, the node will not participate in consensus.
+-  **PATRONI\_RAFT\_PARTNER\_ADDRS**: list of other Patroni nodes in the cluster in format ``"'ip1:port1','ip2:port2'"``. It is important to quote every single entity!
+-  **PATRONI\_RAFT\_DATA\_DIR**: directory where to store Raft log and snapshot. If not specified the current working directory is used.
 
 PostgreSQL
 ----------
@@ -89,10 +123,31 @@ PostgreSQL
 -  **PATRONI\_POSTGRESQL\_PGPASS**: path to the `.pgpass <https://www.postgresql.org/docs/current/static/libpq-pgpass.html>`__ password file. Patroni creates this file before executing pg\_basebackup and under some other circumstances. The location must be writable by Patroni.
 -  **PATRONI\_REPLICATION\_USERNAME**: replication username; the user will be created during initialization. Replicas will use this user to access master via streaming replication
 -  **PATRONI\_REPLICATION\_PASSWORD**: replication password; the user will be created during initialization.
+-  **PATRONI\_REPLICATION\_SSLMODE**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+-  **PATRONI\_REPLICATION\_SSLKEY**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+-  **PATRONI\_REPLICATION\_SSLCERT**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+-  **PATRONI\_REPLICATION\_SSLROOTCERT**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+-  **PATRONI\_REPLICATION\_SSLCRL**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+-  **PATRONI\_REPLICATION\_GSSENCMODE**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+-  **PATRONI\_REPLICATION\_CHANNEL\_BINDING**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
 -  **PATRONI\_SUPERUSER\_USERNAME**: name for the superuser, set during initialization (initdb) and later used by Patroni to connect to the postgres. Also this user is used by pg_rewind.
 -  **PATRONI\_SUPERUSER\_PASSWORD**: password for the superuser, set during initialization (initdb).
+-  **PATRONI\_SUPERUSER\_SSLMODE**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+-  **PATRONI\_SUPERUSER\_SSLKEY**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+-  **PATRONI\_SUPERUSER\_SSLCERT**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+-  **PATRONI\_SUPERUSER\_SSLROOTCERT**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+-  **PATRONI\_SUPERUSER\_SSLCRL**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+-  **PATRONI\_SUPERUSER\_GSSENCMODE**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+-  **PATRONI\_SUPERUSER\_CHANNEL\_BINDING**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
 -  **PATRONI\_REWIND\_USERNAME**: name for the user for ``pg_rewind``; the user will be created during initialization of postgres 11+ and all necessary `permissions <https://www.postgresql.org/docs/11/app-pgrewind.html#id-1.9.5.8.8>`__ will be granted.
 -  **PATRONI\_REWIND\_PASSWORD**: password for the user for ``pg_rewind``; the user will be created during initialization.
+-  **PATRONI\_REWIND\_SSLMODE**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+-  **PATRONI\_REWIND\_SSLKEY**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+-  **PATRONI\_REWIND\_SSLCERT**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+-  **PATRONI\_REWIND\_SSLROOTCERT**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+-  **PATRONI\_REWIND\_SSLCRL**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+-  **PATRONI\_REWIND\_GSSENCMODE**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+-  **PATRONI\_REWIND\_CHANNEL\_BINDING**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
 
 REST API
 --------
@@ -102,7 +157,15 @@ REST API
 -  **PATRONI\_RESTAPI\_PASSWORD**: Basic-auth password to protect unsafe REST API endpoints.
 -  **PATRONI\_RESTAPI\_CERTFILE**: Specifies the file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
 -  **PATRONI\_RESTAPI\_KEYFILE**: Specifies the file with the secret key in the PEM format.
+-  **PATRONI\_RESTAPI\_CAFILE**: Specifies the file with the CA_BUNDLE with certificates of trusted CAs to use while verifying client certs.
+-  **PATRONI\_RESTAPI\_VERIFY\_CLIENT**: ``none`` (default), ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. When ``required`` is used, then client authentication succeeds, if the certificate signature verification succeeds. For ``optional`` the client cert will only be checked for ``PUT``, ``POST``, ``PATCH``, and ``DELETE`` requests.
+-  **PATRONI\_RESTAPI\_HTTP\_EXTRA\_HEADERS**: (optional) HTTP headers let the REST API server pass additional information with an HTTP response.
+-  **PATRONI\_RESTAPI\_HTTPS\_EXTRA\_HEADERS**: (optional) HTTPS headers let the REST API server pass additional information with an HTTP response when TLS is enabled. This will also pass additional information set in ``http_extra_headers``.
 
-ZooKeeper
+CTL
----------
+---
--  **PATRONI\_ZOOKEEPER\_HOSTS**: comma separated list of ZooKeeper cluster members: "'host1:port1','host2:port2','etc...'". It is important to quote every single entity!
+-  **PATRONICTL\_CONFIG\_FILE**: location of the configuration file.
+-  **PATRONI\_CTL\_INSECURE**: Allow connections to REST API without verifying SSL certs.
+-  **PATRONI\_CTL\_CACERT**: Specifies the file with the CA_BUNDLE file or directory with certificates of trusted CAs to use while verifying REST API SSL certs. If not provided patronictl will use the value provided for REST API "cafile" parameter.
+-  **PATRONI\_CTL\_CERTFILE**: Specifies the file with the client certificate in the PEM format. If not provided patronictl will use the value provided for REST API "certfile" parameter.
+-  **PATRONI\_CTL\_KEYFILE**: Specifies the file with the client secret key in the PEM format. If not provided patronictl will use the value provided for REST API "keyfile" parameter.

docs/README.rst

@@ -72,7 +72,7 @@ Patroni can be installed with pip:
 
 where dependencies can be either empty, or consist of one or more of the following:
 
-etcd
+etcd or etcd3
     `python-etcd` module in order to use Etcd as DCS
 consul
     `python-consul` module in order to use Consul as DCS
@@ -82,6 +82,8 @@ exhibitor
     `kazoo` module in order to use Exhibitor as DCS (same dependencies as for Zookeeper)
 kubernetes
     `kubernetes` module in order to use Kubernetes as DCS in Patroni
+raft
+    `pysyncobj` module in order to use python Raft implementation as DCS
 aws
     `boto` in order to use AWS callbacks
 
@@ -97,6 +99,13 @@ independently of Patroni.
 
 .. _running_configuring:
 
+Planning the Number of PostgreSQL Nodes
+---------------------------------------
+
+Patroni/PostgreSQL nodes are decoupled from DCS nodes (except when Patroni implements RAFT on its own) and therefore
+there is no requirement on the minimal number of nodes. Running a cluster consisting of one master and one standby is 
+perfectly fine. You can add more standby nodes later.
+
 Running and Configuring
 -----------------------
 
@@ -107,7 +116,7 @@ obtain those files from the git repository and replace `./patroni.py` below with
 To get started, do the following from different terminals:
 ::
 
-    > etcd --data-dir=data/etcd
+    > etcd --data-dir=data/etcd --enable-v2=true
     > ./patroni.py postgres0.yml
     > ./patroni.py postgres1.yml
 

docs/SETTINGS.rst

@@ -4,6 +4,41 @@
 YAML Configuration Settings
 ===========================
 
+.. _dynamic_configuration_settings:
+
+Dynamic configuration settings
+------------------------------
+
+Dynamic configuration is stored in the DCS (Distributed Configuration Store) and applied on all cluster nodes. Some parameters, like **loop_wait**, **ttl**, **postgresql.parameters.max_connections**, **postgresql.parameters.max_worker_processes** and so on could be set only in the dynamic configuration. Some other parameters like **postgresql.listen**, **postgresql.data_dir** could be set only locally, i.e. in the Patroni config file or via :ref:`configuration <environment>` variable. In most cases the local configuration will override the dynamic configuration. In order to change the dynamic configuration you can use either ``patronictl edit-config`` tool or Patroni :ref:`REST API <rest_api>`.
+
+-  **loop\_wait**: the number of seconds the loop will sleep. Default value: 10
+-  **ttl**: the TTL to acquire the leader lock (in seconds). Think of it as the length of time before initiation of the automatic failover process. Default value: 30
+-  **retry\_timeout**: timeout for DCS and PostgreSQL operation retries (in seconds). DCS or network issues shorter than this will not cause Patroni to demote the leader. Default value: 10
+-  **maximum\_lag\_on\_failover**: the maximum bytes a follower may lag to be able to participate in leader election.
+-  **max\_timelines\_history**: maximum number of timeline history items kept in DCS.  Default value: 0. When set to 0, it keeps the full history in DCS.
+-  **master\_start\_timeout**: the amount of time a master is allowed to recover from failures before failover is triggered (in seconds). Default is 300 seconds. When set to 0 failover is done immediately after a crash is detected if possible. When using asynchronous replication a failover can cause lost transactions. Worst case failover time for master failure is: loop\_wait + master\_start\_timeout + loop\_wait, unless master\_start\_timeout is zero, in which case it's just loop\_wait. Set the value according to your durability/availability tradeoff.
+- **master\_stop\_timeout**: The number of seconds Patroni is allowed to wait when stopping Postgres and effective only when synchronous_mode is enabled. When set to > 0 and the synchronous_mode is enabled, Patroni sends SIGKILL to the postmaster if the stop operation is running for more than the value set by master_stop_timeout. Set the value according to your durability/availability tradeoff. If the parameter is not set or set <= 0, master_stop_timeout does not apply.
+-  **synchronous\_mode**: turns on synchronous replication mode. In this mode a replica will be chosen as synchronous and only the latest leader and synchronous replica are able to participate in leader election. Synchronous mode makes sure that successfully committed transactions will not be lost at failover, at the cost of losing availability for writes when Patroni cannot ensure transaction durability. See :ref:`replication modes documentation <replication_modes>` for details.
+-  **synchronous\_mode\_strict**: prevents disabling synchronous replication if no synchronous replicas are available, blocking all client writes to the master. See :ref:`replication modes documentation <replication_modes>` for details.
+-  **postgresql**:
+    -  **use\_pg\_rewind**: whether or not to use pg_rewind. Defaults to `false`.
+    -  **use\_slots**: whether or not to use replication slots. Defaults to `true` on PostgreSQL 9.4+.
+    -  **recovery\_conf**: additional configuration settings written to recovery.conf when configuring follower. There is no recovery.conf anymore in PostgreSQL 12, but you may continue using this section, because Patroni handles it transparently.
+    -  **parameters**: list of configuration settings for Postgres.
+-  **standby\_cluster**: if this section is defined, we want to bootstrap a standby cluster.
+    -  **host**: an address of remote master
+    -  **port**: a port of remote master
+    -  **primary\_slot\_name**: which slot on the remote master to use for replication. This parameter is optional, the default value is derived from the instance name (see function `slot_name_from_member_name`).
+    -  **create\_replica\_methods**: an ordered list of methods that can be used to bootstrap standby leader from the remote master, can be different from the list defined in :ref:`postgresql_settings`
+    -  **restore\_command**: command to restore WAL records from the remote master to standby leader, can be different from the list defined in :ref:`postgresql_settings`
+    -  **archive\_cleanup\_command**: cleanup command for standby leader
+    -  **recovery\_min\_apply\_delay**: how long to wait before actually apply WAL records on a standby leader
+-  **slots**: define permanent replication slots. These slots will be preserved during switchover/failover. Patroni will try to create slots before opening connections to the cluster.
+    -  **my_slot_name**: the name of replication slot. If the permanent slot name matches with the name of the current primary it will not be created. Everything else is the responsibility of the operator to make sure that there are no clashes in names between replication slots automatically created by Patroni for members and permanent replication slots.
+        -  **type**: slot type. Could be ``physical`` or ``logical``. If the slot is logical, you have to additionally define ``database`` and ``plugin``.
+        -  **database**: the database name where logical slots should be created.
+        -  **plugin**: the plugin name for the logical slot.
+
 Global/Universal
 ----------------
 -  **name**: the name of the host. Must be unique for the cluster.
@@ -13,6 +48,7 @@ Global/Universal
 Log
 ---
 -  **level**: sets the general logging level. Default value is **INFO** (see `the docs for Python logging <https://docs.python.org/3.6/library/logging.html#levels>`_)
+-  **traceback\_level**: sets the level where tracebacks will be visible. Default value is **ERROR**. Set it to **DEBUG** if you want to see tracebacks only if you enable **log.level=DEBUG**.
 -  **format**: sets the log formatting string. Default value is **%(asctime)s %(levelname)s: %(message)s** (see `the LogRecord attributes <https://docs.python.org/3.6/library/logging.html#logrecord-attributes>`_)
 -  **dateformat**: sets the datetime formatting string. (see the `formatTime() documentation <https://docs.python.org/3.6/library/logging.html#logging.Formatter.formatTime>`_)
 -  **max\_queue\_size**: Patroni is using two-step logging. Log records are written into the in-memory queue and there is a separate thread which pulls them from the queue and writes to stderr or file. The maximum size of the internal queue is limited by default by **1000** records, which is enough to keep logs for the past 1h20m.
@@ -27,32 +63,8 @@ Log
 
 Bootstrap configuration
 -----------------------
--  **dcs**: This section will be written into `/<namespace>/<scope>/config` of a given configuration store after initializing of new cluster. This is the global configuration for the cluster. If you want to change some parameters for all cluster nodes - just do it in DCS (or via Patroni API) and all nodes will apply this configuration.
+-  **bootstrap**:
-    -  **loop\_wait**: the number of seconds the loop will sleep. Default value: 10
+    -  **dcs**: This section will be written into `/<namespace>/<scope>/config` of the given configuration store after initializing of new cluster. The global dynamic configuration for the cluster. Under the ``bootstrap.dcs`` you can put any of the parameters described in the :ref:`Dynamic Configuration settings <dynamic_configuration_settings>` and after Patroni initialized (bootstrapped) the new cluster, it will write this section into `/<namespace>/<scope>/config` of the configuration store. All later changes of ``bootstrap.dcs`` will not take any effect! If you want to change them please use either ``patronictl edit-config`` or Patroni :ref:`REST API <rest_api>`.
-    -  **ttl**: the TTL to acquire the leader lock. Think of it as the length of time before initiation of the automatic failover process. Default value: 30
-    -  **retry\_timeout**: timeout for DCS and PostgreSQL operation retries. DCS or network issues shorter than this will not cause Patroni to demote the leader. Default value: 10
-    -  **maximum\_lag\_on\_failover**: the maximum bytes a follower may lag to be able to participate in leader election.
-    -  **master\_start\_timeout**: the amount of time a master is allowed to recover from failures before failover is triggered. Default is 300 seconds. When set to 0 failover is done immediately after a crash is detected if possible. When using asynchronous replication a failover can cause lost transactions. Best worst case failover time for master failure is: loop\_wait + master\_start\_timeout + loop\_wait, unless master\_start\_timeout is zero, in which case it's just loop\_wait. Set the value according to your durability/availability tradeoff.
-    -  **synchronous\_mode**: turns on synchronous replication mode. In this mode a replica will be chosen as synchronous and only the latest leader and synchronous replica are able to participate in leader election. Synchronous mode makes sure that successfully committed transactions will not be lost at failover, at the cost of losing availability for writes when Patroni cannot ensure transaction durability. See :ref:`replication modes documentation <replication_modes>` for details.
-    -  **synchronous\_mode\_strict**: prevents disabling synchronous replication if no synchronous replicas are available, blocking all client writes to the master. See :ref:`replication modes documentation <replication_modes>` for details.
-    -  **postgresql**:
-        -  **use\_pg\_rewind**: whether or not to use pg_rewind
-        -  **use\_slots**: whether or not to use replication_slots. Must be False for PostgreSQL 9.3. You should comment out max_replication_slots before it becomes ineligible for leader status.
-        -  **recovery\_conf**: additional configuration settings written to recovery.conf when configuring follower.
-        -  **parameters**: list of configuration settings for Postgres. Many of these are required for replication to work.
-    -  **standby\_cluster**: if this section is defined, we want to bootstrap a standby cluster.
-        -  **host**: an address of remote master
-        -  **port**: a port of remote master
-        -  **primary\_slot\_name**: which slot on the remote master to use for replication. This parameter is optional, the default value is derived from the instance name (see function `slot_name_from_member_name`).
-        -  **create\_replica\_methods**: an ordered list of methods that can be used to bootstrap standby leader from the remote master, can be different from the list defined in :ref:`postgresql_settings`
-        -  **restore\_command**: command to restore WAL records from the remote master to standby leader, can be different from the list defined in :ref:`postgresql_settings`
-        -  **archive\_cleanup\_command**: cleanup command for standby leader
-        -  **recovery\_min\_apply\_delay**: how long to wait before actually apply WAL records on a standby leader
-    -  **slots**: define permanent replication slots. These slots will be preserved during switchover/failover. Patroni will try to create slots before opening connections to the cluster.
-        -  **my_slot_name**: the name of replication slot. It is the responsibility of the operator to make sure that there are no clashes in names between replication slots automatically created by Patroni for members and permanent replication slots.
-            -  **type**: slot type. Could be ``physical`` or ``logical``. If the slot is logical, you have to additionally define ``database`` and ``plugin``.
-            -  **database**: the database name where logical slots should be created.
-            -  **plugin**: the plugin name for the logical slot.
     -  **method**: custom script to use for bootstrapping this cluster.
        See :ref:`custom bootstrap methods documentation <custom_bootstrap>` for details.
        When ``initdb`` is specified revert to the default ``initdb`` command. ``initdb`` is also triggered when no ``method``
@@ -78,20 +90,35 @@ Consul
 ------
 Most of the parameters are optional, but you have to specify one of the **host** or **url**
 
--  **host**: the host:port for the Consul endpoint, in format: http(s)://host:port
+-  **host**: the host:port for the Consul local agent.
--  **url**: url for the Consul endpoint
+-  **url**: url for the Consul local agent, in format: http(s)://host:port.
--  **port**: (optional) Consul port
+-  **port**: (optional) Consul port.
--  **scheme**: (optional) **http** or **https**, defaults to **http**
+-  **scheme**: (optional) **http** or **https**, defaults to **http**.
--  **token**: (optional) ACL token
+-  **token**: (optional) ACL token.
--  **verify**: (optional) whether to verify the SSL certificate for HTTPS requests
+-  **verify**: (optional) whether to verify the SSL certificate for HTTPS requests.
 -  **cacert**: (optional) The ca certificate. If present it will enable validation.
--  **cert**: (optional) file with the client certificate
+-  **cert**: (optional) file with the client certificate.
 -  **key**: (optional) file with the client key. Can be empty if the key is part of **cert**.
 -  **dc**: (optional) Datacenter to communicate with. By default the datacenter of the host is used.
 -  **consistency**: (optional) Select consul consistency mode. Possible values are ``default``, ``consistent``, or ``stale`` (more details in `consul API reference <https://www.consul.io/api/features/consistency.html/>`__)
--  **checks**: (optional) list of Consul health checks used for the session. If not specified Consul will use "serfHealth" in additional to the TTL based check created by Patroni. Additional checks, in particular the "serfHealth", may cause the leader lock to expire faster than in `ttl` seconds when the leader instance becomes unavailable
+-  **checks**: (optional) list of Consul health checks used for the session. By default an empty list is used.
--  **register\_service**: (optional) whether or not to register a service with the name defined by the scope parameter and the tag master, replica or standby-leader depending on the node's role. Defaults to **false**
+-  **register\_service**: (optional) whether or not to register a service with the name defined by the scope parameter and the tag master, replica or standby-leader depending on the node's role. Defaults to **false**.
--  **service\_check\_interval**: (optional) how often to perform health check against registered url
+-  **service\_tags**: (optional) additional static tags to add to the Consul service apart from the role (``master``/``replica``/``standby-leader``).  By default an empty list is used.
+-  **service\_check\_interval**: (optional) how often to perform health check against registered url.
+
+The ``token`` needs to have the following ACL permissions:
+
+::
+
+    service_prefix "${scope}" {
+        policy = "write"
+    }
+    key_prefix "${namespace}/${scope}" {
+        policy = "write"
+    }
+    session_prefix "" {
+        policy = "write"
+    }
 
 Etcd
 ----
@@ -100,8 +127,8 @@ Most of the parameters are optional, but you have to specify one of the **host**
 -  **host**: the host:port for the etcd endpoint.
 -  **hosts**: list of etcd endpoint in format host1:port1,host2:port2,etc... Could be a comma separated string or an actual yaml list.
 -  **use\_proxies**: If this parameter is set to true, Patroni will consider **hosts** as a list of proxies and will not perform a topology discovery of etcd cluster.
--  **url**: url for the etcd
+-  **url**: url for the etcd.
--  **proxy**: proxy url for the etcd. If you are connecting to the etcd using proxy, use this parameter instead of **url**
+-  **proxy**: proxy url for the etcd. If you are connecting to the etcd using proxy, use this parameter instead of **url**.
 -  **srv**: Domain to search the SRV record(s) for cluster autodiscovery.
 -  **protocol**: (optional) http or https, if not specified http is used. If the **url** or **proxy** is specified - will take protocol from them.
 -  **username**: (optional) username for etcd authentication.
@@ -110,38 +137,115 @@ Most of the parameters are optional, but you have to specify one of the **host**
 -  **cert**: (optional) file with the client certificate.
 -  **key**: (optional) file with the client key. Can be empty if the key is part of **cert**.
 
+Etcdv3
+------
+If you want that Patroni works with Etcd cluster via protocol version 3, you need to use the ``etcd3`` section in the Patroni configuration file. All configuration parameters are the same as for ``etcd``.
+
+.. warning::
+    Keys created with protocol version 2 are not visible with protocol version 3 and the other way around, therefore it is not possible to switch from ``etcd`` to ``etcd3`` just by updating Patroni config file.
+
+
+ZooKeeper
+----------
+-  **hosts**: List of ZooKeeper cluster members in format: ['host1:port1', 'host2:port2', 'etc...'].
+-  **use_ssl**: (optional) Whether SSL is used or not. Defaults to ``false``. If set to ``false``, all SSL specific parameters are ignored.
+-  **cacert**: (optional) The CA certificate. If present it will enable validation.
+-  **cert**: (optional) File with the client certificate.
+-  **key**: (optional) File with the client key.
+-  **key_password**: (optional) The client key password.
+-  **verify**: (optional) Whether to verify certificate or not. Defaults to ``true``.
+
+.. note::
+    It is required to install ``kazoo>=2.6.0`` to support SSL.
+
+
 Exhibitor
 ---------
 -  **hosts**: initial list of Exhibitor (ZooKeeper) nodes in format: 'host1,host2,etc...'. This list updates automatically whenever the Exhibitor (ZooKeeper) cluster topology changes.
--  **poll\_interval**: how often the list of ZooKeeper and Exhibitor nodes should be updated from Exhibitor
+-  **poll\_interval**: how often the list of ZooKeeper and Exhibitor nodes should be updated from Exhibitor.
 -  **port**: Exhibitor port.
 
 .. _kubernetes_settings:
 
 Kubernetes
 ----------
+-  **bypass\_api\_service**: (optional) When communicating with the Kubernetes API, Patroni is usually relying on the `kubernetes` service, the address of which is exposed in the pods via the `KUBERNETES_SERVICE_HOST` environment variable. If `bypass_api_service` is set to ``true``, Patroni will resolve the list of API nodes behind the service and connect directly to them.
 -  **namespace**: (optional) Kubernetes namespace where Patroni pod is running. Default value is `default`.
 -  **labels**: Labels in format ``{label1: value1, label2: value2}``. These labels will be used to find existing objects (Pods and either Endpoints or ConfigMaps) associated with the current cluster. Also Patroni will set them on every object (Endpoint or ConfigMap) it creates.
 -  **scope\_label**: (optional) name of the label containing cluster name. Default value is `cluster-name`.
 -  **role\_label**: (optional) name of the label containing role (master or replica). Patroni will set this label on the pod it runs in. Default value is ``role``.
 -  **use\_endpoints**: (optional) if set to true, Patroni will use Endpoints instead of ConfigMaps to run leader elections and keep cluster state.
 -  **pod\_ip**: (optional) IP address of the pod Patroni is running in. This value is required when `use_endpoints` is enabled and is used to populate the leader endpoint subsets when the pod's PostgreSQL is promoted.
--  **ports**: (optional) if the Service object has the name for the port, the same name must appear in the Endpoint object, otherwise service won't work. For example, if your service is defined as ``{Kind: Service, spec: {ports: [{name: postgresql, port: 5432, targetPort: 5432}]}}``, then you have to set ``kubernetes.ports: {[{"name": "postgresql", "port": 5432}]}`` and Patroni will use it for updating subsets of the leader Endpoint. This parameter is used only if `kubernetes.use_endpoints` is set.
+-  **ports**: (optional) if the Service object has the name for the port, the same name must appear in the Endpoint object, otherwise service won't work. For example, if your service is defined as ``{Kind: Service, spec: {ports: [{name: postgresql, port: 5432, targetPort: 5432}]}}``, then you have to set ``kubernetes.ports: [{"name": "postgresql", "port": 5432}]`` and Patroni will use it for updating subsets of the leader Endpoint. This parameter is used only if `kubernetes.use_endpoints` is set.
+
+
+.. _raft_settings:
+
+Raft
+----
+-  **self\_addr**: ``ip:port`` to listen on for Raft connections. If not set, the node will not participate in consensus.
+-  **partner\_addrs**: list of other Patroni nodes in the cluster in format: ['ip1:port', 'ip2:port', 'etc...']
+-  **data\_dir**: directory where to store Raft log and snapshot. If not specified the current working directory is used.
+
+  Short FAQ about Raft implementation
+
+  - Q: How to list all the nodes providing consensus?
+
+    A: ``syncobj_admin -conn host:port`` -status where the host:port is the address of one of the cluster nodes
+
+  - Q: Node that was a part of consensus and has gone and I can't reuse the same IP for other node. How to remove this node from the consensus?
+
+    A: ``syncobj_admin -conn host:port -remove host2:port2`` where the ``host2:port2`` is the address of the node you want to remove from consensus.
+
+  - Q: Where to get the ``syncobj_admin`` utility?
+
+    A: It is installed together with ``pysyncobj`` module (python RAFT implementation), which is Patroni dependancy.
+
+  - Q: it is possible to run Patroni node without adding in to the consensus?
+
+    A: Yes, just comment out or remove ``raft.self_addr`` from Patroni configuration.
+
+  - Q: It is possible to run Patroni and PostgreSQL only on two nodes?
+
+    A: Yes, on the third node you can run ``patroni_raft_controller`` (without Patroni and PostgreSQL). In such setup one can temporary loose one node without affecting the primary.
+
 
 .. _postgresql_settings:
 
 PostgreSQL
 ----------
+-  **postgresql**:
     -  **authentication**:
         -  **superuser**:
             -  **username**: name for the superuser, set during initialization (initdb) and later used by Patroni to connect to the postgres.
             -  **password**: password for the superuser, set during initialization (initdb).
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **gssencmode**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+            -  **channel_binding**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
         -  **replication**:
             -  **username**: replication username; the user will be created during initialization. Replicas will use this user to access master via streaming replication
             -  **password**: replication password; the user will be created during initialization.
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **gssencmode**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+            -  **channel_binding**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
         -  **rewind**:
             -  **username**: name for the user for ``pg_rewind``; the user will be created during initialization of postgres 11+ and all necessary `permissions <https://www.postgresql.org/docs/11/app-pgrewind.html#id-1.9.5.8.8>`__ will be granted.
             -  **password**: password for the user for ``pg_rewind``; the user will be created during initialization.
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **gssencmode**: (optional) maps to the `gssencmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-GSSENCMODE>`__ connection parameter, which determines whether or with what priority a secure GSS TCP/IP connection will be negotiated with the server
+            -  **channel_binding**: (optional) maps to the `channel_binding <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-CHANNEL-BINDING>`__ connection parameter, which controls the client's use of channel binding.
     -  **callbacks**: callback scripts to run on certain actions. Patroni will pass the action, role and cluster name. (See scripts/aws.py as an example of how to write them.)
             -  **on\_reload**: run this script when configuration reload is triggered.
             -  **on\_restart**: run this script when the postgres restarts (without changing role).
@@ -172,36 +276,65 @@ PostgreSQL
     -  **remove\_data\_directory\_on\_rewind\_failure**: If this option is enabled, Patroni will remove the PostgreSQL data directory and recreate the replica. Otherwise it will try to follow the new leader. Default value is **false**.
     -  **remove\_data\_directory\_on\_diverged\_timelines**: Patroni will remove the PostgreSQL data directory and recreate the replica if it notices that timelines are diverging and the former master can not start streaming from the new master. This option is useful when ``pg_rewind`` can not be used. Default value is **false**.
     -  **replica\_method**: for each create_replica_methods other than basebackup, you would add a configuration section of the same name. At a minimum, this should include "command" with a full path to the actual script to be executed. Other configuration parameters will be passed along to the script in the form "parameter=value".
+    -  **pre\_promote**: a fencing script that executes during a failover after acquiring the leader lock but before promoting the replica. If the script exits with a non-zero code, Patroni does not promote the replica and removes the leader key from DCS.
 
 REST API
 --------
--  **connect\_address**: IP address (or hostname) and port, to access the Patroni's REST API. All the members of the cluster must be able to connect to this address, so unless the Patroni setup is intended for a demo inside the localhost, this address must be a non "localhost" or loopback addres (ie: "localhost" or "127.0.0.1"). It can serve as a endpoint for HTTP health checks (read below about the "listen" REST API parameter), and also for user queries (either directly or via the REST API), as well as for the health checks done by the cluster members during leader elections (for example, to determine whether the master is still running, or if there is a node which has a WAL position that is ahead of the one doing the query; etc.) The connect_address is put in the member key in DCS, making it possible to translate the member name into the address to connect to its REST API.
+-  **restapi**:
+        -  **connect\_address**: IP address (or hostname) and port, to access the Patroni's :ref:`REST API <rest_api>`. All the members of the cluster must be able to connect to this address, so unless the Patroni setup is intended for a demo inside the localhost, this address must be a non "localhost" or loopback address (ie: "localhost" or "127.0.0.1"). It can serve as an endpoint for HTTP health checks (read below about the "listen" REST API parameter), and also for user queries (either directly or via the REST API), as well as for the health checks done by the cluster members during leader elections (for example, to determine whether the master is still running, or if there is a node which has a WAL position that is ahead of the one doing the query; etc.) The connect_address is put in the member key in DCS, making it possible to translate the member name into the address to connect to its REST API.
 
         -  **listen**: IP address (or hostname) and port that Patroni will listen to for the REST API - to provide also the same health checks and cluster messaging between the participating nodes, as described above. to provide health-check information for HAProxy (or any other load balancer capable of doing a HTTP "OPTION" or "GET" checks).
 
--  **Optional**:
+        -  **authentication**: (optional)
-        -  **authentication**:
             -  **username**: Basic-auth username to protect unsafe REST API endpoints.
             -  **password**: Basic-auth password to protect unsafe REST API endpoints.
+        -  **certfile**: (optional): Specifies the file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
+        -  **keyfile**: (optional): Specifies the file with the secret key in the PEM format.
+        -  **cafile**: (optional): Specifies the file with the CA_BUNDLE with certificates of trusted CAs to use while verifying client certs.
+        -  **verify\_client**: (optional): ``none`` (default), ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. When ``required`` is used, then client authentication succeeds, if the certificate signature verification succeeds.  For ``optional`` the client cert will only be checked for ``PUT``, ``POST``, ``PATCH``, and ``DELETE`` requests.
+        -  **http\_extra\_headers**: (optional): HTTP headers let the REST API server pass additional information with an HTTP response.
+        -  **https\_extra\_headers**: (optional): HTTPS headers let the REST API server pass additional information with an HTTP response when TLS is enabled. This will also pass additional information set in ``http_extra_headers``.
 
-        -  **certfile**: Specifies the file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
+Here is an example of both **http_extra_headers** and **https_extra_headers**:
-        -  **keyfile**: Specifies the file with the secret key in the PEM format.
+
+.. code:: YAML
+
+        restapi:
+          listen: <listen>
+          connect_address: <connect_address>
+          authentication:
+            username: <username>
+            password: <password>
+          http_extra_headers:
+            'X-Frame-Options': 'SAMEORIGIN'
+            'X-XSS-Protection': '1; mode=block'
+            'X-Content-Type-Options': 'nosniff'
+          cafile: <ca file>
+          certfile: <cert>
+          keyfile: <key>
+          https_extra_headers:
+            'Strict-Transport-Security': 'max-age=31536000; includeSubDomains'
 
 .. _patronictl_settings:
 
 CTL
 ---
--  **Optional**:
+- **ctl**: (optional)
     -  **insecure**: Allow connections to REST API without verifying SSL certs.
-    -  **cacert**: Specifices the file with the CA_BUNDLE file or directory with certificates of trusted CAs to use while verifying REST API SSL certs.
+    -  **cacert**: Specifies the file with the CA_BUNDLE file or directory with certificates of trusted CAs to use while verifying REST API SSL certs. If not provided patronictl will use the value provided for REST API "cafile" parameter.
-    -  **certfile**: Specifies the file with the certificate in the PEM format to use while verifying REST API SSL certs. If not provided patronictl will use the value provided for REST API "certfile" parameter.
+    -  **certfile**: Specifies the file with the client certificate in the PEM format. If not provided patronictl will use the value provided for REST API "certfile" parameter.
-
+    -  **keyfile**: Specifies the file with the client secret key in the PEM format. If not provided patronictl will use the value provided for REST API "keyfile" parameter.
-ZooKeeper
-----------
--  **hosts**: list of ZooKeeper cluster members in format: ['host1:port1', 'host2:port2', 'etc...'].
 
 Watchdog
 --------
 - **mode**: ``off``, ``automatic`` or ``required``. When ``off`` watchdog is disabled. When ``automatic`` watchdog will be used if available, but ignored if it is not. When ``required`` the node will not become a leader unless watchdog can be successfully enabled.
 - **device**: Path to watchdog device. Defaults to ``/dev/watchdog``.
 - **safety_margin**: Number of seconds of safety margin between watchdog triggering and leader key expiration.
+
+Tags
+----
+- **nofailover**: ``true`` or ``false``, controls whether this node is allowed to participate in the leader race and become a leader. Defaults to ``false``
+- **clonefrom**: ``true`` or ``false``. If set to ``true`` other nodes might prefer to use this node for bootstrap (take ``pg_basebackup`` from). If there are several nodes with ``clonefrom`` tag set to ``true`` the node to bootstrap from will be chosen randomly. The default value is ``false``.
+- **noloadbalance**: ``true`` or ``false``. If set to ``true`` the node will return HTTP Status Code 503 for the ``GET /replica`` REST API health-check and therefore will be excluded from the load-balancing. Defaults to ``false``.
+- **replicatefrom**: The IP address/hostname of another replica. Used to support cascading replication.
+- **nosync**: ``true`` or ``false``. If set to ``true`` the node will never be selected as a synchronous replica.

docs/dynamic_configuration.rst

@@ -14,12 +14,14 @@ Patroni configuration is stored in the DCS (Distributed Configuration Store). Th
 
 - Local :ref:`configuration <settings>` (patroni.yml).
 	These options are defined in the configuration file and take precedence over dynamic configuration.
-	patroni.yml could be changed and reload in runtime (without restart of Patroni) by sending SIGHUP to the Patroni process or by performing ``POST /reload`` REST-API request.
+	patroni.yml could be changed and reloaded in runtime (without restart of Patroni) by sending SIGHUP to the Patroni process, performing ``POST /reload`` REST-API request or executing ``patronictl reload``.
 
 - Environment :ref:`configuration <environment>`.
 	It is possible to set/override some of the "Local" configuration parameters with environment variables.
 	Environment configuration is very useful when you are running in a dynamic environment and you don't know some of the parameters in advance (for example it's not possible to know your external IP address when you are running inside ``docker``).
 
+The local configuration can be either a single YAML file or a directory. When it is a directory, all YAML files in that directory are loaded one by one in sorted order. In case a key is defined in multiple files, the occurrence in the last file takes precedence.
+
 Some of the PostgreSQL parameters must hold the same values on the master and the replicas. For those, values set either in the local patroni configuration files or via the environment variables take no effect. To alter or set their values one must change the shared configuration in the DCS. Below is the actual list of such parameters together with the default values:
 
 - max_connections: 100
@@ -35,6 +37,7 @@ For the parameters below, PostgreSQL does not require equal values among the mas
 - max_wal_senders: 5
 - max_replication_slots: 5
 - wal_keep_segments: 8
+- wal_keep_size: 128MB
 
 These parameters are validated to ensure they are sane, or meet a minimum value.
 
@@ -76,6 +79,7 @@ Also, the following Patroni configuration options can be changed only dynamicall
 - loop_wait: 10
 - retry_timeouts: 10
 - maximum_lag_on_failover: 1048576
+- max_timelines_history: 0
 - check_timeline: false
 - postgresql.use_slots: true
 
@@ -83,147 +87,3 @@ Upon changing these options, Patroni will read the relevant section of the confi
 run-time values.
 
 Patroni nodes are dumping the state of the DCS options to disk upon for every change of the configuration into the file ``patroni.dynamic.json`` located in the Postgres data directory. Only the master is allowed to restore these options from the on-disk dump if these are completely absent from the DCS or if they are invalid.
-
-REST API
-========
-
-We provide a REST API endpoint for working with dynamic configuration.
-
-GET /config
------------
-Get current version of dynamic configuration.
-
-.. code-block:: bash
-
-	$ curl -s localhost:8008/config | jq .
-	{
-	  "ttl": 30,
-	  "loop_wait": 10,
-	  "retry_timeout": 10,
-	  "maximum_lag_on_failover": 1048576,
-	  "postgresql": {
-	    "use_slots": true,
-	    "use_pg_rewind": true,
-	    "parameters": {
-	      "hot_standby": "on",
-	      "wal_log_hints": "on",
-	      "wal_keep_segments": 8,
-	      "wal_level": "hot_standby",
-	      "max_wal_senders": 5,
-	      "max_replication_slots": 5,
-	      "max_connections": "100"
-	    }
-	  }
-	}
-
-PATCH /config
--------------
-Change existing configuration.
-
-.. code-block:: bash
-
-	$ curl -s -XPATCH -d \
-		'{"loop_wait":5,"ttl":20,"postgresql":{"parameters":{"max_connections":"101"}}}' \
-		http://localhost:8008/config | jq .
-	{
-	  "ttl": 20,
-	  "loop_wait": 5,
-	  "maximum_lag_on_failover": 1048576,
-	  "retry_timeout": 10,
-	  "postgresql": {
-	    "use_slots": true,
-	    "use_pg_rewind": true,
-	    "parameters": {
-	      "hot_standby": "on",
-	      "wal_log_hints": "on",
-	      "wal_keep_segments": 8,
-	      "wal_level": "hot_standby",
-	      "max_wal_senders": 5,
-	      "max_replication_slots": 5,
-	      "max_connections": "101"
-	    }
-	  }
-	}
-
-The above REST API call patches the existing configuration and returns the new configuration.
-
-Let's check that the node processed this configuration. First of all it should start printing log lines every 5 seconds (loop_wait=5). The change of "max_connections" requires a restart, so the "restart_pending" flag should be exposed:
-
-.. code-block:: bash
-
-	$ curl -s http://localhost:8008/patroni | jq .
-	{
-	  "pending_restart": true,
-	  "database_system_identifier": "6287881213849985952",
-	  "postmaster_start_time": "2016-06-13 13:13:05.211 CEST",
-	  "xlog": {
-	    "location": 2197818976
-	  },
-	  "patroni": {
-	    "scope": "batman",
-	    "version": "1.0"
-	  },
-	  "state": "running",
-	  "role": "master",
-	  "server_version": 90503
-	}
-
-Removing parameters:
-
-If you want to remove (reset) some setting just patch it with ``null``:
-
-.. code-block:: bash
-
-	$ curl -s -XPATCH -d \
-		'{"postgresql":{"parameters":{"max_connections":null}}}' \
-		http://localhost:8008/config | jq .
-	{
-	  "ttl": 20,
-	  "loop_wait": 5,
-	  "retry_timeout": 10,
-	  "maximum_lag_on_failover": 1048576,
-	  "postgresql": {
-	    "use_slots": true,
-	    "use_pg_rewind": true,
-	    "parameters": {
-	      "hot_standby": "on",
-	      "unix_socket_directories": ".",
-	      "wal_keep_segments": 8,
-	      "wal_level": "hot_standby",
-	      "wal_log_hints": "on",
-	      "max_wal_senders": 5,
-	      "max_replication_slots": 5
-	    }
-	  }
-	}
-
-Above call removes ``postgresql.parameters.max_connections`` from the dynamic configuration.
-
-PUT /config
------------
-
-It's also possible to perform the full rewrite of an existing dynamic configuration unconditionally:
-
-.. code-block:: bash
-
-	$ curl -s -XPUT -d \
-		'{"maximum_lag_on_failover":1048576,"retry_timeout":10,"postgresql":{"use_slots":true,"use_pg_rewind":true,"parameters":{"hot_standby":"on","wal_log_hints":"on","wal_keep_segments":8,"wal_level":"hot_standby","unix_socket_directories":".","max_wal_senders":5}},"loop_wait":3,"ttl":20}' \
-		http://localhost:8008/config | jq .
-	{
-	  "ttl": 20,
-	  "maximum_lag_on_failover": 1048576,
-	  "retry_timeout": 10,
-	  "postgresql": {
-	    "use_slots": true,
-	    "parameters": {
-	      "hot_standby": "on",
-	      "unix_socket_directories": ".",
-	      "wal_keep_segments": 8,
-	      "wal_level": "hot_standby",
-	      "wal_log_hints": "on",
-	      "max_wal_senders": 5
-	    },
-	    "use_pg_rewind": true
-	  },
-	  "loop_wait": 3
-	}

docs/existing_data.rst

@@ -23,6 +23,21 @@ A Patroni cluster can be started with a data directory from a single-node Postgr
 3. Start Patroni (e.g. ``patroni /etc/patroni/patroni.yml``). It automatically detects that PostgreSQL daemon is already running but its configuration might be out-of-date.
 4. Ask Patroni to restart the node with ``patronictl restart cluster-name node-name``. This step is only required if PostgreSQL configuration is out-of-date.
 
+Major Upgrade of PostgreSQL Version
+===================================
+
+The only possible way to do a major upgrade currently is:
+
+1. Stop Patroni
+2. Upgrade PostgreSQL binaries and perform `pg_upgrade <https://www.postgresql.org/docs/current/pgupgrade.html>`_ on the master node
+3. Update patroni.yml
+4. Remove the initialize key from DCS or wipe complete cluster state from DCS. The second one could be achieved by running ``patronictl remove <cluster-name>``. It is necessary because pg_upgrade runs initdb which actually creates a new database with a new PostgreSQL system identifier.
+5. If you wiped the cluster state in the previous step, you may wish to copy patroni.dynamic.json from old data dir to the new one.  It will help you to retain some PostgreSQL parameters you had set before.
+6. Start Patroni on the master node.
+7. Upgrade PostgreSQL binaries, update patroni.yml and wipe the data_dir on standby nodes.
+8. Start Patroni on the standby nodes and wait for the replication to complete.
+
+Running pg_upgrade on standby nodes is not supported by PostgreSQL. If you know what you are doing, you can try the rsync procedure described in https://www.postgresql.org/docs/current/pgupgrade.html instead of wiping data_dir on standby nodes. The safest way is however to let Patroni replicate the data for you.
 
 FAQ
 ---

docs/index.rst

@@ -19,8 +19,10 @@ We call Patroni a "template" because it is far from being a one-size-fits-all or
 
    README
    dynamic_configuration
+   rest_api
    ENVIRONMENT
    SETTINGS
+   security
    replica_bootstrap
    replication_modes
    pause

docs/releases.rst

@@ -3,6 +3,604 @@
 Release notes
 =============
 
+Version 2.0.0
+-------------
+
+This version enhances compatibility with PostgreSQL 13, adds support of multiple synchronous standbys, has significant improvements in handling of ``pg_rewind``, adds support of Etcd v3 and Patroni on pure RAFT (without Etcd, Consul, or Zookeeper), and makes it possible to optionally call the ``pre_promote`` (fencing) script.
+
+**PostgreSQL 13 support**
+
+- Don't fire ``on_reload`` when promoting to ``standby_leader`` on PostgreSQL 13+ (Alexander Kukushkin)
+
+  When promoting to ``standby_leader`` we change ``primary_conninfo``, update the role and reload Postgres. Since ``on_role_change`` and ``on_reload`` effectively duplicate each other, Patroni will call only ``on_role_change``.
+
+- Added support for ``gssencmode`` and ``channel_binding`` connection parameters (Alexander)
+
+  PostgreSQL 12 introduced ``gssencmode`` and 13 ``channel_binding`` connection parameters and now they can be used if defined in the ``postgresql.authentication`` section.
+
+- Handle renaming of ``wal_keep_segments`` to ``wal_keep_size`` (Alexander)
+
+  In case of misconfiguration (``wal_keep_segments`` on 13 and ``wal_keep_size`` on older versions) Patroni will automatically adjust the configuration.
+
+- Use ``pg_rewind`` with ``--restore-target-wal`` on 13 if possible (Alexander)
+
+  On PostgreSQL 13 Patroni checks if ``restore_command`` is configured and tells ``pg_rewind`` to use it.
+
+
+**New features**
+
+- [BETA] Implemented support of Patroni on pure RAFT (Alexander)
+
+  This makes it possible to run Patroni without 3rd party dependencies, like Etcd, Consul, or Zookeeper. For HA you will have to run either three Patroni nodes or two nodes with Patroni and one node with ``patroni_raft_controller``. For more information please check the :ref:`documentation <raft_settings>`.
+
+- [BETA] Implemented support for Etcd v3 protocol via gPRC-gateway (Alexander)
+
+  Etcd 3.0 was released more than four years ago and Etcd 3.4 has v2 disabled by default. There are also chances that v2 will be completely removed from Etcd, therefore we implemented support of Etcd v3 in Patroni. In order to start using it you have to explicitly create the ``etcd3`` section is the Patroni configuration file.
+
+- Supporting multiple synchronous standbys (Krishna Sarabu)
+
+  It allows running a cluster with more than one synchronous replicas. The maximum number of synchronous replicas is controlled by the new parameter ``synchronous_node_count``. It is set to 1 by default and has no effect when the ``synchronous_mode`` is set to ``off``.
+
+- Added possibility to call the ``pre_promote`` script (Sergey Dudoladov)
+
+  Unlike callbacks, the ``pre_promote`` script is called synchronously after acquiring the leader lock, but before promoting Postgres. If the script fails or exits with a non-zero exitcode, the current node will release the leader lock.
+
+- Added support for configuration directories (Floris van Nee)
+
+  YAML files in the directory loaded and applied in alphabetical order.
+
+- Advanced validation of PostgreSQL parameters (Alexander)
+
+  In case the specific parameter is not supported by the current PostgreSQL version or when its value is incorrect, Patroni will remove the parameter completely or try to fix the value.
+
+- Wake up the main thread when the forced checkpoint after promote completed (Alexander)
+
+  Replicas are waiting for checkpoint indication via member key of the leader in DCS. The key is normally updated only once per HA loop. Without waking the main thread up, replicas will have to wait up to ``loop_wait`` seconds longer than necessary.
+
+- Use of ``pg_stat_wal_recevier`` view on 9.6+ (Alexander)
+
+  The view contains up-to-date values of ``primary_conninfo`` and ``primary_slot_name``, while the contents of ``recovery.conf`` could be stale.
+
+- Improved handing of IPv6 addresses in the Patroni config file (Mateusz Kowalski)
+
+  The IPv6 address is supposed to be enclosed into square brackets, but Patroni was expecting to get it plain. Now both formats are supported.
+
+- Added Consul ``service_tags`` configuration parameter (Robert Edström)
+
+  They are useful for dynamic service discovery, for example by load balancers.
+
+- Implemented SSL support for Zookeeper (Kostiantyn Nemchenko)
+
+  It requires ``kazoo>=2.6.0``.
+
+- Implemented ``no_params`` option for custom bootstrap method (Kostiantyn)
+
+  It allows calling ``wal-g``, ``pgBackRest`` and other backup tools without wrapping them into shell scripts.
+
+- Move WAL and tablespaces after a failed init (Feike Steenbergen)
+
+  When doing ``reinit``, Patroni was already removing not only ``PGDATA`` but also the symlinked WAL directory and tablespaces. Now the ``move_data_directory()`` method will do a similar job, i.e. rename WAL directory and tablespaces and update symlinks in PGDATA.
+
+
+**Improved in pg_rewind support**
+
+- Improved timeline divergence check (Alexander)
+
+  We don't need to rewind when the replayed location on the replica is not ahead of the switchpoint or the end of the checkpoint record on the former primary is the same as the switchpoint. In order to get the end of the checkpoint record we use ``pg_waldump`` and parse its output.
+
+- Try to fetch missing WAL if ``pg_rewind`` complains about it (Alexander)
+
+  It could happen that the WAL segment required for ``pg_rewind`` doesn't exist in the ``pg_wal`` directory anymore and therefore ``pg_rewind`` can't find the checkpoint location before the divergence point. Starting from PostgreSQL 13 ``pg_rewind`` could use ``restore_command`` for fetching missing WALs. For older PostgreSQL versions Patroni parses the errors of a failed rewind attempt and tries to fetch the missing WAL by calling the ``restore_command`` on its own.
+
+- Detect a new timeline in the standby cluster and trigger rewind/reinitialize if necessary (Alexander)
+
+  The ``standby_cluster`` is decoupled from the primary cluster and therefore doesn't immediately know about leader elections and timeline switches. In order to detect the fact, the ``standby_leader`` periodically checks for new history files in ``pg_wal``.
+
+- Shorten and beautify history log output (Alexander)
+
+  When Patroni is trying to figure out the necessity of ``pg_rewind``, it could write the content of the history file from the primary into the log. The history file is growing with every failover/switchover and eventually starts taking up too many lines, most of which are not so useful. Instead of showing the raw data, Patroni will show only 3 lines before the current replica timeline and 2 lines after.
+
+
+**Improvements on K8s**
+
+- Get rid of ``kubernetes`` python module (Alexander)
+
+  The official python kubernetes client contains a lot of auto-generated code and therefore very heavy. Patroni uses only a small fraction of K8s API endpoints and implementing support for them wasn't hard.
+
+- Make it possible to bypass the ``kubernetes`` service (Alexander)
+
+  When running on K8s, Patroni is usually communicating with the K8s API via the ``kubernetes`` service, the address of which is exposed in the ``KUBERNETES_SERVICE_HOST`` environment variable. Like any other service, the ``kubernetes`` service is handled by ``kube-proxy``, which in turn, depending on the configuration, is either relying on a userspace program or ``iptables`` for traffic routing. Skipping the intermediate component and connecting directly to the K8s master nodes allows us to implement a better retry strategy and mitigate risks of demoting Postgres when K8s master nodes are upgraded.
+
+- Sync HA loops of all pods of a Patroni cluster (Alexander)
+
+  Not doing so was increasing failure detection time from ``ttl`` to ``ttl + loop_wait``.
+
+- Populate ``references`` and ``nodename`` in the subsets addresses on K8s (Alexander)
+
+  Some load-balancers are relying on this information.
+
+- Fix possible race conditions in the ``update_leader()`` (Alexander)
+
+  The concurrent update of the leader configmap or endpoint happening outside of Patroni might cause the ``update_leader()`` call to fail. In this case Patroni rechecks that the current node is still owning the leader lock and repeats the update.
+
+- Explicitly disallow patching non-existent config (Alexander)
+
+  For DCS other than ``kubernetes`` the PATCH call is failing with an exception due to ``cluster.config`` being ``None``, but on Kubernetes it was happily creating the config annotation and preventing writing bootstrap configuration after the bootstrap finished.
+
+- Fix bug in ``pause`` (Alexander)
+
+  Replicas were removing ``primary_conninfo`` and restarting Postgres when the leader key was absent, but they should do nothing.
+
+
+**Improvements in REST API**
+
+- Defer TLS handshake until worker thread has started (Alexander, Ben Harris)
+
+  If the TLS handshake was done in the API thread and the client-side didn't send any data, the API thread was blocked (risking DoS).
+
+- Check ``basic-auth`` independently from client certificate in REST API (Alexander)
+
+  Previously only the client certificate was validated. Doing two checks independently is an absolutely valid use-case.
+
+- Write double ``CRLF`` after HTTP headers of the ``OPTIONS`` request (Sergey Burladyan)
+
+  HAProxy was happy with a single ``CRLF``, while Consul health-check complained about broken connection and unexpected EOF.
+
+- ``GET /cluster`` was showing stale members info for Zookeeper (Alexander)
+
+  The endpoint was using the Patroni internal cluster view. For Patroni itself it didn't cause any issues, but when exposed to the outside world we need to show up-to-date information, especially replication lag.
+
+- Fixed health-checks for standby cluster (Alexander)
+
+  The ``GET /standby-leader`` for a master and ``GET /master`` for a ``standby_leader`` were incorrectly responding with 200.
+
+- Implemented ``DELETE /switchover`` (Alexander)
+
+  The REST API call deletes the scheduled switchover.
+
+- Created ``/readiness`` and ``/liveness`` endpoints (Alexander)
+
+  They could be useful to eliminate "unhealthy" pods from subsets addresses when the K8s service is used with label selectors.
+
+- Enhanced ``GET /replica`` and ``GET /async`` REST API health-checks (Krishna, Alexander)
+
+  Checks now support optional keyword ``?lag=<max-lag>`` and will respond with 200 only if the lag is smaller than the supplied value. If relying on this feature please keep in mind that information about WAL position on the leader is updated only every ``loop_wait`` seconds!
+
+- Added support for user defined HTTP headers in the REST API response (Yogesh Sharma)
+
+  This feature might be useful if requests are made from a browser.
+
+
+**Improvements in patronictl**
+
+- Don't try to call non-existing leader in ``patronictl pause`` (Alexander)
+
+  While pausing a cluster without a leader on K8s, ``patronictl`` was showing warnings that member "None" could not be accessed.
+
+- Handle the case when member ``conn_url`` is missing (Alexander)
+
+  On K8s it is possible that the pod doesn't have the necessary annotations because Patroni is not yet running. It was making ``patronictl`` to fail.
+
+- Added ability to print ASCII cluster topology (Maxim Fedotov, Alexander)
+
+  It is very useful to get overview of the cluster with cascading replication.
+
+- Implement ``patronictl flush switchover`` (Alexander)
+
+  Before that ``patronictl flush`` only supported cancelling scheduled restarts.
+
+
+**Bugfixes**
+
+- Attribute error during bootstrap of the cluster with existing PGDATA (Krishna)
+
+  When trying to create/update the ``/history`` key, Patroni was accessing the ``ClusterConfig`` object which wasn't created in DCS yet.
+
+- Improved exception handling in Consul (Alexander)
+
+  Unhandled exception in the ``touch_member()`` method caused the whole Patroni process to crash.
+
+- Enforce ``synchronous_commit=local`` for the ``post_init`` script (Alexander)
+
+  Patroni was already doing that when creating users (``replication``, ``rewind``), but missing it in the case of ``post_init`` was an oversight. As a result, if the script wasn't doing it internally on it's own the bootstrap in ``synchronous_mode`` wasn't able to finish.
+
+- Increased ``maxsize`` in the Consul pool manager (ponvenkates)
+
+  With the default ``size=1`` some warnings were generated.
+
+- Patroni was wrongly reporting Postgres as running (Alexander)
+
+  The state wasn't updated when for example Postgres crashed due to an out-of-disk error.
+
+- Put ``*`` into ``pgpass`` instead of missing or empty values (Alexander)
+
+  If for example the ``standby_cluster.port`` is not specified, the ``pgpass`` file was incorrectly generated.
+
+- Skip physical replication slot creation on the leader node with special characters (Krishna)
+
+  Patroni appeared to be creating a dormant slot (when ``slots`` defined) for the leader node when the name contained special chars such as '-'  (for e.g. "abc-us-1").
+
+- Avoid removing non-existent ``pg_hba.conf`` in the custom bootstrap (Krishna)
+
+  Patroni was failing if ``pg_hba.conf`` happened to be located outside of the ``pgdata`` dir after custom bootstrap.
+
+
+Version 1.6.5
+-------------
+
+**New features**
+
+- Master stop timeout (Krishna Sarabu)
+
+  The number of seconds Patroni is allowed to wait when stopping Postgres. Effective only when ``synchronous_mode`` is enabled. When set to value greater than 0 and the ``synchronous_mode`` is enabled, Patroni sends ``SIGKILL`` to the postmaster if the stop operation is running for more than the value set by ``master_stop_timeout``. Set the value according to your durability/availability tradeoff. If the parameter is not set or set to non-positive value, ``master_stop_timeout`` does not have an effect.
+
+- Don't create permanent physical slot with name of the primary (Alexander Kukushkin)
+
+  It is a common problem that the primary recycles WAL segments while the replica is down. Now we have a good solution for static clusters, with a fixed number of nodes and names that never change. You just need to list the names of all nodes in the ``slots`` so the primary will not remove the slot when the node is down (not registered in DCS).
+
+- First draft of Config Validator (Igor Yanchenko)
+
+  Use ``patroni --validate-config patroni.yaml`` in order to validate Patroni configuration.
+
+- Possibility to configure max length of timelines history (Krishna)
+
+  Patroni writes the history of failovers/switchovers into the ``/history`` key in DCS. Over time the size of this key becomes big, but in most cases only the last few lines are interesting. The ``max_timelines_history`` parameter allows to specify the maximum number of timeline history items to be kept in DCS.
+
+- Kazoo 2.7.0 compatibility (Danyal Prout)
+
+  Some non-public methods in Kazoo changed their signatures, but Patroni was relying on them.
+
+
+**Improvements in patronictl**
+
+- Show member tags (Kostiantyn Nemchenko, Alexander)
+
+  Tags are configured individually for every node and there was no easy way to get an overview of them
+
+- Improve members output (Alexander)
+
+  The redundant cluster name won't be shown anymore on every line, only in the table header.
+
+.. code-block:: bash
+
+    $ patronictl list
+    + Cluster: batman (6813309862653668387) +---------+----+-----------+---------------------+
+    |    Member   |      Host      |  Role  |  State  | TL | Lag in MB | Tags                |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+    | postgresql0 | 127.0.0.1:5432 | Leader | running |  3 |           | clonefrom: true     |
+    |             |                |        |         |    |           | noloadbalance: true |
+    |             |                |        |         |    |           | nosync: true        |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+    | postgresql1 | 127.0.0.1:5433 |        | running |  3 |       0.0 |                     |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+
+- Fail if a config file is specified explicitly but not found (Kaarel Moppel)
+
+  Previously ``patronictl`` was only reporting a ``DEBUG`` message.
+
+- Solved the problem of not initialized K8s pod breaking patronictl (Alexander)
+
+  Patroni is relying on certain pod annotations on K8s. When one of the Patroni pods is stopping or starting there is no valid annotation yet and ``patronictl`` was failing with an exception.
+
+
+**Stability improvements**
+
+- Apply 1 second backoff if LIST call to K8s API server failed (Alexander)
+
+  It is mostly necessary to avoid flooding logs, but also helps to prevent starvation of the main thread.
+
+- Retry if the ``retry-after`` HTTP header is returned by K8s API (Alexander)
+
+  If the K8s API server is overwhelmed with requests it might ask to retry.
+
+- Scrub ``KUBERNETES_`` environment from the postmaster (Feike Steenbergen)
+
+  The ``KUBERNETES_`` environment variables are not required for PostgreSQL, yet having them exposed to the postmaster will also expose them to backends and to regular database users (using pl/perl for example).
+
+- Clean up tablespaces on reinitialize (Krishna)
+
+  During reinit, Patroni was removing only ``PGDATA`` and leaving user-defined tablespace directories. This is causing Patroni to loop in reinit. The previous workarond for the problem was implementing the :ref:`custom bootstrap <custom_bootstrap>` script.
+
+- Explicitly execute ``CHECKPOINT`` after promote happened (Alexander)
+
+  It helps to reduce the time before the new primary is usable for ``pg_rewind``.
+
+- Smart refresh of Etcd members (Alexander)
+
+  In case Patroni failed to execute a request on all members of the Etcd cluster, Patroni will re-check ``A`` or ``SRV`` records for changes of IPs/hosts before retrying the next time.
+
+- Skip missing values from ``pg_controldata`` (Feike)
+
+  Values are missing when trying to use binaries of a version that doesn't match PGDATA. Patroni will try to start Postgres anyway, and Postgres will complain that the major version doesn't match and abort with an error.
+
+
+**Bugfixes**
+
+- Disable SSL verification for Consul when required (Julien Riou)
+
+  Starting from a certain version of ``urllib3``, the ``cert_reqs`` must be explicitly set to ``ssl.CERT_NONE`` in order to effectively disable SSL verification.
+
+- Avoid opening replication connection on every cycle of HA loop (Alexander)
+
+  Regression was introduced in 1.6.4.
+
+- Call ``on_role_change`` callback on failed primary (Alexander)
+
+  In certain cases it could lead to the virtual IP remaining attached to the old primary. Regression was introduced in 1.4.5.
+
+- Reset rewind state if postgres started after successful pg_rewind (Alexander)
+
+  As a result of this bug Patroni was starting up manually shut down postgres in the pause mode.
+
+- Convert ``recovery_min_apply_delay`` to ``ms`` when checking ``recovery.conf``
+
+  Patroni was indefinitely restarting replica if ``recovery_min_apply_delay`` was configured on PostgreSQL older than 12.
+
+- PyInstaller compatibility (Alexander)
+
+  PyInstaller freezes (packages) Python applications into stand-alone executables. The compatibility was broken when we switched to the ``spawn`` method instead of ``fork`` for ``multiprocessing``.
+
+
+Version 1.6.4
+-------------
+
+**New features**
+
+- Implemented ``--wait`` option for ``patronictl reinit`` (Igor Yanchenko)
+
+  Patronictl will wait for ``reinit`` to finish is the ``--wait`` option is used.
+
+- Further improvements of Windows support (Igor Yanchenko, Alexander Kukushkin)
+
+  1. All shell scripts which are used for integration testing are rewritten in python
+  2. The ``pg_ctl kill`` will be used to stop postgres on non posix systems
+  3. Don't try to use unix-domain sockets
+
+
+**Stability improvements**
+
+- Make sure ``unix_socket_directories`` and ``stats_temp_directory`` exist (Igor)
+
+  Upon the start of Patroni and Postgres make sure that ``unix_socket_directories`` and ``stats_temp_directory`` exist or try to create them. Patroni will exit if failed to create them.
+
+- Make sure ``postgresql.pgpass`` is located in the place where Patroni has write access (Igor)
+
+  In case if it doesn't have a write access Patroni will exit with exception.
+
+- Disable Consul ``serfHealth`` check by default (Kostiantyn Nemchenko)
+
+  Even in case of little network problems the failing ``serfHealth`` leads to invalidation of all sessions associated with the node. Therefore, the leader key is lost much earlier than ``ttl`` which causes unwanted restarts of replicas and maybe demotion of the primary.
+
+- Configure tcp keepalives for connections to K8s API (Alexander)
+
+  In case if we get nothing from the socket after TTL seconds it can be considered dead.
+
+- Avoid logging of passwords on user creation (Alexander)
+
+  If the password is rejected or logging is configured to verbose or not configured at all it might happen that the password is written into postgres logs. In order to avoid it Patroni will change ``log_statement``, ``log_min_duration_statement``, and ``log_min_error_statement`` to some safe values before doing the attempt to create/update user.
+
+
+**Bugfixes**
+
+- Use ``restore_command`` from the ``standby_cluster`` config on cascading replicas (Alexander)
+
+  The ``standby_leader`` was already doing it from the beginning the feature existed. Not doing the same on replicas might prevent them from catching up with standby leader.
+
+- Update timeline reported by the standby cluster (Alexander)
+
+  In case of timeline switch the standby cluster was correctly replicating from the primary but ``patronictl`` was reporting the old timeline.
+
+- Allow certain recovery parameters be defined in the custom_conf (Alexander)
+
+  When doing validation of recovery parameters on replica Patroni will skip ``archive_cleanup_command``, ``promote_trigger_file``, ``recovery_end_command``, ``recovery_min_apply_delay``, and ``restore_command`` if they are not defined in the patroni config but in files other than ``postgresql.auto.conf`` or ``postgresql.conf``.
+
+- Improve handling of postgresql parameters with period in its name (Alexander)
+
+  Such parameters could be defined by extensions where the unit is not necessarily a string. Changing the value might require a restart (for example ``pg_stat_statements.max``).
+
+- Improve exception handling during shutdown (Alexander)
+
+  During shutdown Patroni is trying to update its status in the DCS. If the DCS is inaccessible an exception might be raised. Lack of exception handling was preventing logger thread from stopping.
+
+
+Version 1.6.3
+-------------
+
+**Bugfixes**
+
+- Don't expose password when running ``pg_rewind`` (Alexander Kukushkin)
+
+  Bug was introduced in the `#1301 <https://github.com/zalando/patroni/pull/1301>`__
+
+- Apply connection parameters specified in the ``postgresql.authentication`` to ``pg_basebackup`` and custom replica creation methods (Alexander)
+
+  They were relying on url-like connection string and therefore parameters never applied.
+
+
+Version 1.6.2
+-------------
+
+**New features**
+
+- Implemented ``patroni --version`` (Igor Yanchenko)
+
+  It prints the current version of Patroni and exits.
+
+- Set the ``user-agent`` http header for all http requests (Alexander Kukushkin)
+
+  Patroni is communicating with Consul, Etcd, and Kubernetes API via the http protocol. Having a specifically crafted ``user-agent`` (example: ``Patroni/1.6.2 Python/3.6.8 Linux``) might be useful for debugging and monitoring.
+
+- Make it possible to configure log level for exception tracebacks (Igor)
+
+  If you set ``log.traceback_level=DEBUG`` the tracebacks will be visible only when ``log.level=DEBUG``. The default behavior remains the same.
+
+
+**Stability improvements**
+
+- Avoid importing all DCS modules when searching for the module required by the config file (Alexander)
+
+  There is no need to import modules for Etcd, Consul, and Kubernetes if we need only e.g. Zookeeper. It helps to reduce memory usage and solves the problem of having INFO messages ``Failed to import smth``.
+
+- Removed python ``requests`` module from explicit requirements (Alexander)
+
+  It wasn't used for anything critical, but causing a lot of problems when the new version of ``urllib3`` is released.
+
+- Improve handling of ``etcd.hosts`` written as a comma-separated string instead of YAML array (Igor)
+
+  Previously it was failing when written in format ``host1:port1, host2:port2`` (the space character after the comma).
+
+
+**Usability improvements**
+
+- Don't force users to choose members from an empty list in ``patronictl`` (Igor)
+
+  If the user provides a wrong cluster name, we will raise an exception rather than ask to choose a member from an empty list.
+
+- Make the error message more helpful if the REST API cannot bind (Igor)
+
+  For an inexperienced user it might be hard to figure out what is wrong from the Python stacktrace.
+
+
+**Bugfixes**
+
+- Fix calculation of ``wal_buffers`` (Alexander)
+
+  The base unit has been changed from 8 kB blocks to bytes in PostgreSQL 11.
+
+- Use ``passfile`` in ``primary_conninfo`` only on PostgreSQL 10+ (Alexander)
+
+  On older versions there is no guarantee that ``passfile`` will work, unless the latest version of ``libpq`` is installed.
+
+
+Version 1.6.1
+-------------
+
+**New features**
+
+- Added ``PATRONICTL_CONFIG_FILE`` environment variable (msvechla)
+
+  It allows configuring the ``--config-file`` argument for ``patronictl`` from the environment.
+
+- Implement ``patronictl history`` (Alexander Kukushkin)
+
+  It shows the history of failovers/switchovers.
+
+- Pass ``-c statement_timeout=0`` in ``PGOPTIONS`` when doing ``pg_rewind`` (Alexander Kukushkin)
+
+  It protects from the case when ``statement_timeout`` on the server is set to some small value and one of the statements executed by pg_rewind is canceled.
+
+- Allow lower values for PostgreSQL configuration (Soulou)
+
+  Patroni didn't allow some of the PostgreSQL configuration parameters be set smaller than some hardcoded values. Now the minimal allowed values are smaller, default values have not been changed.
+
+- Allow for certificate-based authentication (Jonathan S. Katz)
+
+  This feature enables certificate-based authentication for superuser, replication, rewind accounts and allows the user to specify the ``sslmode`` they wish to connect with.
+
+- Use the ``passfile`` in the ``primary_conninfo`` instead of password (Alexander Kukushkin)
+
+  It allows to avoid setting ``600`` permissions on postgresql.conf
+
+- Perform ``pg_ctl reload`` regardless of config changes (Alexander Kukushkin)
+
+  It is possible that some config files are not controlled by Patroni. When somebody is doing a reload via the REST API or by sending SIGHUP to the Patroni process, the usual expectation is that Postgres will also be reloaded. Previously it didn't happen when there were no changes in the ``postgresql`` section of Patroni config.
+
+- Compare all recovery parameters, not only ``primary_conninfo`` (Alexander Kukushkin)
+
+  Previously the ``check_recovery_conf()`` method was only checking whether ``primary_conninfo`` has changed, never taking into account all other recovery parameters.
+
+- Make it possible to apply some recovery parameters without restart (Alexander Kukushkin)
+
+  Starting from PostgreSQL 12 the following recovery parameters could be changed without restart: ``archive_cleanup_command``, ``promote_trigger_file``, ``recovery_end_command``, and ``recovery_min_apply_delay``. In future Postgres releases this list will be extended and Patroni will support it automatically.
+
+- Make it possible to change ``use_slots`` online (Alexander Kukushkin)
+
+  Previously it required restarting Patroni and removing slots manually.
+
+- Remove only ``PATRONI_`` prefixed environment variables when starting up Postgres (Cody Coons)
+
+  It will solve a lot of problems with running different Foreign Data Wrappers.
+
+
+**Stability improvements**
+
+- Use LIST + WATCH when working with K8s API (Alexander Kukushkin)
+
+  It allows to efficiently receive object changes (pods, endpoints/configmaps) and makes less stress on K8s master nodes.
+
+- Improve the workflow when PGDATA is not empty during bootstrap (Alexander Kukushkin)
+
+  According to the ``initdb`` source code it might consider a PGDATA empty when there are only ``lost+found`` and ``.dotfiles`` in it. Now Patroni does the same. If ``PGDATA`` happens to be non-empty, and at the same time not valid from the ``pg_controldata`` point of view, Patroni will complain and exit.
+
+- Avoid calling expensive ``os.listdir()`` on every HA loop (Alexander Kukushkin)
+
+  When the system is under IO stress, ``os.listdir()`` could take a few seconds (or even minutes) to execute, badly affecting the HA loop of Patroni. This could even cause the leader key to disappear from DCS due to the lack of updates. There is a better and less expensive way to check that the PGDATA is not empty. Now we check the presence of the ``global/pg_control`` file in the PGDATA.
+
+- Some improvements in logging infrastructure (Alexander Kukushkin)
+
+  Previously threre was a possibility to loose the last few log lines on shutdown because the logging thread was a ``daemon`` thread.
+
+- Use ``spawn`` multiprocessing start method on python 3.4+ (Maciej Kowalczyk)
+
+  It is a known `issue <https://bugs.python.org/issue6721>`__ in Python that threading and multiprocessing do not mix well. Switching from the default method ``fork`` to the ``spawn`` is a recommended workaround. Not doing so might result in the Postmaster starting process hanging and Patroni indefinitely reporting ``INFO: restarting after failure in progress``, while  Postgres is actually up and running.
+
+**Improvements in REST API**
+
+- Make it possible to check client certificates in the REST API (Alexander Kukushkin)
+
+  If the ``verify_client`` is set to ``required``, Patroni will check client certificates for all REST API calls. When it is set to ``optional``, client certificates are checked for all unsafe REST API endpoints.
+
+- Return the response code 503 for the ``GET /replica`` health check request if Postgres is not running (Alexander Anikin)
+
+  Postgres might spend significant time in recovery before it starts accepting client connections.
+
+- Implement ``/history`` and ``/cluster`` endpoints (Alexander Kukushkin)
+
+  The ``/history`` endpoint shows the content of the ``history`` key in DCS. The ``/cluster`` endpoint shows all cluster members and some service info like pending and scheduled restarts or switchovers.
+
+
+**Improvements in Etcd support**
+
+- Retry on Etcd RAFT internal error (Alexander Kukushkin)
+
+  When the Etcd node is being shut down, it sends ``response code=300, data='etcdserver: server stopped'``, which was causing Patroni to demote the primary.
+
+- Don't give up on Etcd request retry too early (Alexander Kukushkin)
+
+  When there were some network problems, Patroni was quickly exhausting the list of Etcd nodes and giving up without using the whole ``retry_timeout``, potentially resulting in demoting the primary.
+
+
+**Bugfixes**
+
+- Disable ``synchronous_commit`` when granting execute permissions to the ``pg_rewind`` user (kremius)
+
+  If the bootstrap is done with ``synchronous_mode_strict: true`` the `GRANT EXECUTE` statement was waiting indefinitely due to the non-synchronous nodes being available.
+
+- Fix memory leak on python 3.7 (Alexander Kukushkin)
+
+  Patroni is using ``ThreadingMixIn`` to process REST API requests and python 3.7 made threads spawn for every request non-daemon by default.
+
+- Fix race conditions in asynchronous actions (Alexander Kukushkin)
+
+  There was a chance that ``patronictl reinit --force`` could be overwritten by the attempt to recover stopped Postgres. This ended up in a situation when Patroni was trying to start Postgres while basebackup was running.
+
+- Fix race condition in ``postmaster_start_time()`` method (Alexander Kukushkin)
+
+  If the method is executed from the REST API thread, it requires a separate cursor object to be created.
+
+- Fix the problem of not promoting the sync standby that had a name contaning upper case letters (Alexander Kukushkin)
+
+  We converted the name to the lower case because Postgres was doing the same while comparing the ``application_name`` with the value in ``synchronous_standby_names``.
+
+- Kill all children along with the callback process before starting the new one (Alexander Kukushkin)
+
+  Not doing so makes it hard to implement callbacks in bash and eventually can lead to the situation when two callbacks are running at the same time. 
+
+- Fix 'start failed' issue (Alexander Kukushkin)
+
+  Under certain conditions the Postgres state might be set to 'start failed' despite Postgres being up and running.
+
+
 Version 1.6.0
 -------------
 

docs/replica_bootstrap.rst

@@ -24,6 +24,7 @@ arguments to them, i.e. the name of the cluster and the path to the data directo
         <custom_bootstrap_method_name>:
             command: <path_to_custom_bootstrap_script> [param1 [, ...]]
             keep_existing_recovery_conf: False
+            no_params: False
             recovery_conf:
                 recovery_target_action: promote
                 recovery_target_timeline: latest
@@ -40,6 +41,8 @@ in the configuration files, Patroni supplies two cluster-specific ones:
 --datadir
     Path to the data directory of the cluster instance to be bootstrapped
 
+Passing these two additional flags can be disabled by setting a special ``no_params`` parameter to ``True``.
+
 If the bootstrap script returns 0, Patroni tries to configure and start the PostgreSQL instance produced by it. If any
 of the intermediate steps fail, or the script returns a non-zero value, Patroni assumes that the bootstrap has failed,
 cleans up after itself and releases the initialize lock to give another node the opportunity to bootstrap.
@@ -127,7 +130,7 @@ A special ``no_master`` parameter, if defined, allows Patroni to call the replic
 running master or replicas. In that case, an empty string will be passed in a connection string. This is useful for
 restoring the formerly running cluster from the binary backup.
 
-A special ``keep_data`` parameter, if defined, will instuct Patroni to  not clean PGDATA folder before calling restore.
+A special ``keep_data`` parameter, if defined, will instruct Patroni to  not clean PGDATA folder before calling restore.
 
 A special ``no_params`` parameter, if defined, restricts passing parameters to custom command.
 
@@ -204,4 +207,4 @@ in a patroni configuration:
 Note, that these options will be applied only once during cluster bootstrap,
 and the only way to change them afterwards is through DCS.
 
-If you use replication slots on the standby cluster, you must also create the corresponding replication slot on the primary cluster.  It will not be done automatically by the standby cluster implementation.  You can use Patroni's permenant replication slots feature on the primary cluster to maintain a replication slot with the same name as ``primary_slot_name``, or its default value if ``primary_slot_name`` is not provided.
+If you use replication slots on the standby cluster, you must also create the corresponding replication slot on the primary cluster.  It will not be done automatically by the standby cluster implementation.  You can use Patroni's permanent replication slots feature on the primary cluster to maintain a replication slot with the same name as ``primary_slot_name``, or its default value if ``primary_slot_name`` is not provided.

docs/replication_modes.rst

@@ -46,7 +46,7 @@ When ``synchronous_mode`` is on and a standby crashes, commits will block until
 
 When it is absolutely necessary to guarantee that each write is stored durably
 on at least two nodes, enable ``synchronous_mode_strict`` in addition to the
-``synchronous_node``. This parameter prevents Patroni from switching off the
+``synchronous_mode``. This parameter prevents Patroni from switching off the
 synchronous replication on the primary when no synchronous standby candidates
 are available. As a downside, the primary is not be available for writes
 (unless the Postgres transaction explicitly turns of ``synchronous_mode``),
@@ -57,11 +57,16 @@ You can ensure that a standby never becomes the synchronous standby by setting `
 
 Synchronous mode can be switched on and off via Patroni REST interface. See :ref:`dynamic configuration <dynamic_configuration>` for instructions.
 
+Note: Because of the way synchronous replication is implemented in PostgreSQL it is still possible to lose transactions even when using ``synchronous_mode_strict``. If the PostgreSQL backend is cancelled while waiting to acknowledge replication (as a result of packet cancellation due to client timeout or backend failure) transaction changes become visible for other backends. Such changes are not yet replicated and may be lost in case of standby promotion.
+
+Synchronous Replication Factor
+------------------------------
+The parameter ``synchronous_node_count`` is used by Patroni to manage number of synchronous standby databases. It is set to 1 by default. It has no effect when ``synchronous_mode`` is set to off. When enabled, Patroni manages precise number of synchronous standby databases based on parameter ``synchronous_node_count`` and adjusts the state in DCS & synchronous_standby_names as members join and leave.
 
 Synchronous mode implementation
 -------------------------------
 
-When in synchronous mode Patroni maintains synchronization state in the DCS, containing the latest primary and current synchronous standby. This state is updated with strict ordering constraints to ensure the following invariants:
+When in synchronous mode Patroni maintains synchronization state in the DCS, containing the latest primary and current synchronous standby databases. This state is updated with strict ordering constraints to ensure the following invariants:
 
 - A node must be marked as the latest leader whenever it can accept write transactions. Patroni crashing or PostgreSQL not shutting down can cause violations of this invariant.
 
@@ -69,9 +74,9 @@ When in synchronous mode Patroni maintains synchronization state in the DCS, con
 
 - A node that is not the leader or current synchronous standby is not allowed to promote itself automatically.
 
-Patroni will only ever assign one standby to ``synchronous_standby_names`` because with multiple candidates it is not possible to know which node was acting as synchronous during the failure.
+Patroni will only assign one or more synchronous standby nodes based on ``synchronous_node_count`` parameter to ``synchronous_standby_names``.
 
-On each HA loop iteration Patroni re-evaluates synchronous standby choice. If the current synchronous standby is connected and has not requested its synchronous status to be removed it remains picked. Otherwise the cluster member available for sync that is furthest ahead in replication is picked.
+On each HA loop iteration Patroni re-evaluates synchronous standby nodes choice. If the current list of synchronous standby nodes are connected and has not requested its synchronous status to be removed it remains picked. Otherwise the cluster member available for sync that is furthest ahead in replication is picked.
 
 
 .. [1] The data is still there, but recovering it requires a manual recovery effort by data recovery specialists. When Patroni is allowed to rewind with ``use_pg_rewind`` the forked timeline will be automatically erased to rejoin the failed primary with the cluster.

docs/rest_api.rst

@@ -0,0 +1,379 @@
+.. _rest_api:
+
+Patroni REST API
+================
+
+Patroni has a rich REST API, which is used by Patroni itself during the leader race, by the ``patronictl`` tool in order to perform failovers/switchovers/reinitialize/restarts/reloads, by HAProxy or any other kind of load balancer to perform HTTP health checks, and of course could also be used for monitoring. Below you will find the list of Patroni REST API endpoints.
+
+Health check endpoints
+----------------------
+For all health check ``GET`` requests Patroni returns a JSON document with the status of the node, along with the HTTP status code. If you don't want or don't need the JSON document, you might consider using the ``OPTIONS`` method instead of ``GET``.
+
+- The following requests to Patroni REST API will return HTTP status code **200** only when the Patroni node is running as the leader:
+
+  - ``GET /``
+  - ``GET /master``
+  - ``GET /leader``
+  - ``GET /primary``
+  - ``GET /read-write``
+
+- ``GET /replica``: replica health check endpoint. It returns HTTP status code **200** only when the Patroni node is in the state ``running``, the role is ``replica`` and ``noloadbalance`` tag is not set.
+
+- ``GET /replica?lag=<max-lag>``: replica check endpoint. In addition to checks from ``replica``, it also checks replication latency and returns status code **200** only when it is below specified value. The key cluster.last_leader_operation from DCS is used for Leader wal position and compute latency on replica for performance reasons. max-lag can be specified in bytes (integer) or in human readable values, for e.g. 16kB, 64MB, 1GB.
+
+  - ``GET /replica?lag=1048576``
+  - ``GET /replica?lag=1024kB``
+  - ``GET /replica?lag=10MB``
+  - ``GET /replica?lag=1GB``
+
+- ``GET /read-only``: like the above endpoint, but also includes the primary.
+
+- ``GET /standby-leader``: returns HTTP status code **200** only when the Patroni node is running as the leader in a :ref:`standby cluster <standby_cluster>`.
+
+- ``GET /synchronous`` or ``GET /sync``: returns HTTP status code **200** only when the Patroni node is running as a synchronous standby.
+
+- ``GET /asynchronous`` or ``GET /async``: returns HTTP status code **200** only when the Patroni node is running as an asynchronous standby.
+
+- ``GET /asynchronous?lag=<max-lag>`` or ``GET /async?lag=<max-lag>``: asynchronous standby check endpoint. In addition to checks from ``asynchronous`` or ``async``, it also checks replication latency and returns status code **200** only when it is below specified value. The key cluster.last_leader_operation from DCS is used for Leader wal position and compute latency on replica for performance reasons. max-lag can be specified in bytes (integer) or in human readable values, for e.g. 16kB, 64MB, 1GB.
+
+  - ``GET /async?lag=1048576``
+  - ``GET /async?lag=1024kB``
+  - ``GET /async?lag=10MB``
+  - ``GET /async?lag=1GB``
+
+- ``GET /health``: returns HTTP status code **200** only when PostgreSQL is up and running.
+
+- ``GET /liveness``: always returns HTTP status code **200** what only indicates that Patroni is running. Could be used for ``livenessProbe``.
+
+- ``GET /readiness``: returns HTTP status code **200** when the Patroni node is running as the leader or when PostgreSQL is up and running. The endpoint could be used for ``readinessProbe`` when it is not possible to use Kubenetes endpoints for leader elections (OpenShift).
+
+Both, ``readiness`` and ``liveness`` endpoints are very light-weight and not executing any SQL. Probes should be configured in such a way that they start failing about time when the leader key is expiring. With the default value of ``ttl``, which is ``30s`` example probes would look like:
+
+.. code-block:: yaml
+
+    readinessProbe:
+      httpGet:
+        scheme: HTTP
+        path: /readiness
+        port: 8008
+      initialDelaySeconds: 3
+      periodSeconds: 10
+      timeoutSeconds: 5
+      successThreshold: 1
+      failureThreshold: 3
+    livenessProbe:
+      httpGet:
+        scheme: HTTP
+        path: /liveness
+        port: 8008
+      initialDelaySeconds: 3
+      periodSeconds: 10
+      timeoutSeconds: 5
+      successThreshold: 1
+      failureThreshold: 3
+
+
+Monitoring endpoint
+-------------------
+
+The ``GET /patroni`` is used by Patroni during the leader race. It also could be used by your monitoring system. The JSON document produced by this endpoint has the same structure as the JSON produced by the health check endpoints.
+
+.. code-block:: bash
+
+    $ curl -s http://localhost:8008/patroni | jq .
+    {
+      "state": "running",
+      "postmaster_start_time": "2019-09-24 09:22:32.555 CEST",
+      "role": "master",
+      "server_version": 110005,
+      "cluster_unlocked": false,
+      "xlog": {
+        "location": 25624640
+      },
+      "timeline": 3,
+      "database_system_identifier": "6739877027151648096",
+      "patroni": {
+        "version": "1.6.0",
+        "scope": "batman"
+      }
+    }
+
+Cluster status endpoints
+------------------------
+
+- The ``GET /cluster`` endpoint generates a JSON document describing the current cluster topology and state:
+
+.. code-block:: bash
+
+    $ curl -s http://localhost:8008/cluster | jq .
+    {
+      "members": [
+        {
+          "name": "postgresql0",
+          "host": "127.0.0.1",
+          "port": 5432,
+          "role": "leader",
+          "state": "running",
+          "api_url": "http://127.0.0.1:8008/patroni",
+          "timeline": 5,
+          "tags": {
+            "clonefrom": true
+          }
+        },
+        {
+          "name": "postgresql1",
+          "host": "127.0.0.1",
+          "port": 5433,
+          "role": "replica",
+          "state": "running",
+          "api_url": "http://127.0.0.1:8009/patroni",
+          "timeline": 5,
+          "tags": {
+            "clonefrom": true
+          },
+          "lag": 0
+        }
+      ],
+      "scheduled_switchover": {
+        "at": "2019-09-24T10:36:00+02:00",
+        "from": "postgresql0"
+      }
+    }
+
+
+- The ``GET /history`` endpoint provides a view on the history of cluster switchovers/failovers. The format is very similar to the content of history files in the ``pg_wal`` directory. The only difference is the timestamp field showing when the new timeline was created.
+
+.. code-block:: bash
+
+    $ curl -s http://localhost:8008/history | jq .
+    [
+      [
+        1,
+        25623960,
+        "no recovery target specified",
+        "2019-09-23T16:57:57+02:00"
+      ],
+      [
+        2,
+        25624344,
+        "no recovery target specified",
+        "2019-09-24T09:22:33+02:00"
+      ],
+      [
+        3,
+        25624752,
+        "no recovery target specified",
+        "2019-09-24T09:26:15+02:00"
+      ],
+      [
+        4,
+        50331856,
+        "no recovery target specified",
+        "2019-09-24T09:35:52+02:00"
+      ]
+    ]
+
+
+Config endpoint
+---------------
+
+``GET /config``: Get the current version of the dynamic configuration:
+
+.. code-block:: bash
+
+	$ curl -s localhost:8008/config | jq .
+	{
+	  "ttl": 30,
+	  "loop_wait": 10,
+	  "retry_timeout": 10,
+	  "maximum_lag_on_failover": 1048576,
+	  "postgresql": {
+	    "use_slots": true,
+	    "use_pg_rewind": true,
+	    "parameters": {
+	      "hot_standby": "on",
+	      "wal_log_hints": "on",
+	      "wal_level": "hot_standby",
+	      "max_wal_senders": 5,
+	      "max_replication_slots": 5,
+	      "max_connections": "100"
+	    }
+	  }
+	}
+
+
+``PATCH /config``: Change the existing configuration.
+
+.. code-block:: bash
+
+	$ curl -s -XPATCH -d \
+		'{"loop_wait":5,"ttl":20,"postgresql":{"parameters":{"max_connections":"101"}}}' \
+		http://localhost:8008/config | jq .
+	{
+	  "ttl": 20,
+	  "loop_wait": 5,
+	  "maximum_lag_on_failover": 1048576,
+	  "retry_timeout": 10,
+	  "postgresql": {
+	    "use_slots": true,
+	    "use_pg_rewind": true,
+	    "parameters": {
+	      "hot_standby": "on",
+	      "wal_log_hints": "on",
+	      "wal_level": "hot_standby",
+	      "max_wal_senders": 5,
+	      "max_replication_slots": 5,
+	      "max_connections": "101"
+	    }
+	  }
+	}
+
+The above REST API call patches the existing configuration and returns the new configuration.
+
+Let's check that the node processed this configuration. First of all it should start printing log lines every 5 seconds (loop_wait=5). The change of "max_connections" requires a restart, so the "pending_restart" flag should be exposed:
+
+.. code-block:: bash
+
+	$ curl -s http://localhost:8008/patroni | jq .
+	{
+	  "pending_restart": true,
+	  "database_system_identifier": "6287881213849985952",
+	  "postmaster_start_time": "2016-06-13 13:13:05.211 CEST",
+	  "xlog": {
+	    "location": 2197818976
+	  },
+	  "patroni": {
+	    "scope": "batman",
+	    "version": "1.0"
+	  },
+	  "state": "running",
+	  "role": "master",
+	  "server_version": 90503
+	}
+
+Removing parameters:
+
+If you want to remove (reset) some setting just patch it with ``null``:
+
+.. code-block:: bash
+
+	$ curl -s -XPATCH -d \
+		'{"postgresql":{"parameters":{"max_connections":null}}}' \
+		http://localhost:8008/config | jq .
+	{
+	  "ttl": 20,
+	  "loop_wait": 5,
+	  "retry_timeout": 10,
+	  "maximum_lag_on_failover": 1048576,
+	  "postgresql": {
+	    "use_slots": true,
+	    "use_pg_rewind": true,
+	    "parameters": {
+	      "hot_standby": "on",
+	      "unix_socket_directories": ".",
+	      "wal_level": "hot_standby",
+	      "wal_log_hints": "on",
+	      "max_wal_senders": 5,
+	      "max_replication_slots": 5
+	    }
+	  }
+	}
+
+The above call removes ``postgresql.parameters.max_connections`` from the dynamic configuration.
+
+``PUT /config``: It's also possible to perform the full rewrite of an existing dynamic configuration unconditionally:
+
+.. code-block:: bash
+
+	$ curl -s -XPUT -d \
+		'{"maximum_lag_on_failover":1048576,"retry_timeout":10,"postgresql":{"use_slots":true,"use_pg_rewind":true,"parameters":{"hot_standby":"on","wal_log_hints":"on","wal_level":"hot_standby","unix_socket_directories":".","max_wal_senders":5}},"loop_wait":3,"ttl":20}' \
+		http://localhost:8008/config | jq .
+	{
+	  "ttl": 20,
+	  "maximum_lag_on_failover": 1048576,
+	  "retry_timeout": 10,
+	  "postgresql": {
+	    "use_slots": true,
+	    "parameters": {
+	      "hot_standby": "on",
+	      "unix_socket_directories": ".",
+	      "wal_level": "hot_standby",
+	      "wal_log_hints": "on",
+	      "max_wal_senders": 5
+	    },
+	    "use_pg_rewind": true
+	  },
+	  "loop_wait": 3
+	}
+
+
+Switchover and failover endpoints
+---------------------------------
+
+``POST /switchover`` or ``POST /failover``. These endpoints are very similar to each other. There are a couple of minor differences though:
+
+1. The failover endpoint allows to perform a manual failover when there are no healthy nodes, but at the same time it will not allow you to schedule a switchover.
+
+2. The switchover endpoint is the opposite. It works only when the cluster is healthy (there is a leader) and allows to schedule a switchover at a given time.
+
+
+In the JSON body of the ``POST`` request you must specify at least the ``leader`` or ``candidate`` fields and optionally the ``scheduled_at`` field if you want to schedule a switchover at a specific time.
+
+
+Example: perform a failover to the specific node:
+
+.. code-block:: bash
+
+    $ curl -s http://localhost:8009/failover -XPOST -d '{"candidate":"postgresql1"}'
+    Successfully failed over to "postgresql1"
+
+
+Example: schedule a switchover from the leader to any other healthy replica in the cluster at a specific time:
+
+.. code-block:: bash
+
+    $ curl -s http://localhost:8008/switchover -XPOST -d \
+	    '{"leader":"postgresql0","scheduled_at":"2019-09-24T12:00+00"}'
+    Switchover scheduled
+
+
+Depending on the situation the request might finish with a different HTTP status code and body. The status code **200** is returned when the switchover or failover successfully completed. If the switchover was successfully scheduled, Patroni will return HTTP status code **202**. In case something went wrong, the error status code (one of **400**, **412** or **503**) will be returned with some details in the response body. For more information please check the source code of ``patroni/api.py:do_POST_failover()`` method.
+
+- ``DELETE /switchover``: delete the scheduled switchover
+
+The ``POST /switchover`` and ``POST failover`` endpoints are used by ``patronictl switchover`` and ``patronictl failover``, respectively.
+The ``DELETE /switchover`` is used by ``patronictl flush <cluster-name> switchover``.
+
+
+Restart endpoint
+----------------
+
+- ``POST /restart``: You can restart Postgres on the specific node by performing the ``POST /restart`` call. In the JSON body of ``POST`` request it is possible to optionally specify some restart conditions:
+
+  - **restart_pending**: boolean, if set to ``true`` Patroni will restart PostgreSQL only when restart is pending in order to apply some changes in the PostgreSQL config.
+  - **role**: perform restart only if the current role of the node matches with the role from the POST request.
+  - **postgres_version**: perform restart only if the current version of postgres is smaller than specified in the POST request.
+  - **timeout**: how long we should wait before PostgreSQL starts accepting connections. Overrides ``master_start_timeout``.
+  - **schedule**: timestamp with time zone, schedule the restart somewhere in the future.
+
+- ``DELETE /restart``: delete the scheduled restart
+
+``POST /restart`` and ``DELETE /restart`` endpoints are used by ``patronictl restart`` and ``patronictl flush <cluster-name> restart`` respectively.
+
+
+Reload endpoint
+---------------
+
+The ``POST /reload`` call will order Patroni to re-read and apply the configuration file. This is the equivalent of sending the ``SIGHUP`` signal to the Patroni process. In case you changed some of the Postgres parameters which require a restart (like **shared_buffers**), you still have to explicitly do the restart of Postgres by either calling the ``POST /restart`` endpoint or with the help of ``patronictl restart``.
+
+The reload endpoint is used by ``patronictl reload``.
+
+
+Reinitialize endpoint
+---------------------
+
+``POST /reinitialize``: reinitialize the PostgreSQL data directory on the specified node. It is allowed to be executed only on replicas. Once called, it will remove the data directory and start ``pg_basebackup`` or some alternative :ref:`replica creation method <custom_replica_creation>`.
+
+The call might fail if Patroni is in a loop trying to recover (restart) a failed Postgres. In order to overcome this problem one can specify ``{"force":true}`` in the request body.
+
+The reinitialize endpoint is used by ``patronictl reinit``.

docs/security.rst

@@ -0,0 +1,37 @@
+.. _security:
+
+=======================
+Security Considerations
+=======================
+
+A Patroni cluster has two interfaces to be protected from unauthorized access: the distributed configuration storage (DCS) and the Patroni REST API.
+
+Protecting DCS
+==============
+
+Patroni and patronictl both store and retrieve data to/from the DCS. 
+
+Despite DCS doesn't contain any sensitive information, it allows changing some of Patroni/Postgres configuration. Therefore the very first thing that should be protected is DCS itself.
+
+The details of protection depend on the type of DCS used. The authentication and encryption parameters (tokens/basic-auth/client certificates) for the supported types of DCS are covered in :ref:`SETTINGS <bootstrap_settings>` 
+
+The general recommendation is to enable TLS for all DCS communication.
+
+Protecting the REST API
+=======================
+
+Protecting the REST API is a more complicated task.
+
+The Patroni REST API is used by Patroni itself during the leader race, by the ``patronictl`` tool in order to perform failovers/switchovers/reinitialize/restarts/reloads, by HAProxy or any other kind of load balancer to perform HTTP health checks, and of course could also be used for monitoring. 
+
+From the point of view of security, REST API contains safe (``GET`` requests, only retrieve information) and unsafe (``PUT``, ``POST``, ``PATCH`` and ``DELETE`` requests, change the state of nodes) endpoints.
+
+The unsafe endpoints can be protected with HTTP basic-auth by setting the ``restapi.authentication.username`` and ``restapi.authentication.password`` parameters. There is no way to protect the safe endpoints without enabling TLS.
+
+When TLS for the REST API is enabled and a PKI is established, mutual authentication of the API server and API client is possible for all endpoints.
+
+The ``restapi`` section parameters enable TLS client authentication to the server. Depending on the value of the ``verify_client`` parameter, the API server requires a successful client certificate verification for both safe and unsafe API calls (``verify_client: required``), or only for unsafe API calls (``verify_client: optional``), or for no API calls (``verify_client: none``).
+
+The ``ctl`` section parameters enable TLS server authentication to the client (the ``patronictl`` tool which uses the same config as patroni). Set ``insecure: true`` to disable the server certificate verification by the client. See :ref:`SETTINGS <patronictl_settings>` for a detailed description of the TLS client parameters.
+
+Protecting the PostgreSQL database proper from unauthorized access is beyond the scope of this document and is covered in https://www.postgresql.org/docs/current/client-authentication.html

features/archive-restore.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+import os
+import argparse
+import shutil
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--dirname", required=True)
+    parser.add_argument("--pathname", required=True)
+    parser.add_argument("--filename", required=True)
+    parser.add_argument("--mode", required=True, choices=("archive", "restore"))
+    args, _ = parser.parse_known_args()
+
+    full_filename = os.path.join(args.dirname, args.filename)
+    if args.mode == "archive":
+        if not os.path.isdir(args.dirname):
+            os.makedirs(args.dirname)
+        if not os.path.exists(full_filename):
+            shutil.copy(args.pathname, full_filename)
+    else:
+        shutil.copy(full_filename, args.pathname)

features/backup_create.py

@@ -0,0 +1,14 @@
+#!/usr/bin/env python
+import argparse
+import subprocess
+import sys
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--datadir", required=True)
+    parser.add_argument("--dbname", required=True)
+    parser.add_argument("--walmethod", required=True, choices=("fetch", "stream", "none"))
+    args, _ = parser.parse_known_args()
+
+    walmethod = ["-X", args.walmethod] if args.walmethod != "none" else []
+    sys.exit(subprocess.call(["pg_basebackup", "-D", args.datadir, "-c", "fast", "-d", args.dbname] + walmethod))

features/backup_create.sh

@@ -1,22 +0,0 @@
-#!/bin/bash
-
-while getopts ":-:" optchar; do
-    [[ "${optchar}" == "-" ]] || continue
-    case "${OPTARG}" in
-        datadir=* )
-            PGDATA=${OPTARG#*=}
-            ;;
-        dbname=* )
-            DBNAME=${OPTARG#*=}
-            ;;
-        walmethod=* )
-            WALMETHOD=${OPTARG#*=}
-            ;;
-    esac
-done
-
-[[ -z $PGDATA || -z $DBNAME || -z $WALMETHOD ]] && exit 1
-
-[[ $WALMETHOD != "none" ]] && WALMETHOD="-X $WALMETHOD" || WALMETHOD=""
-
-exec pg_basebackup -D $PGDATA $WALMETHOD -c fast -d $DBNAME

features/backup_restore.py

@@ -0,0 +1,11 @@
+#!/usr/bin/env python
+import argparse
+import shutil
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--datadir", required=True)
+    parser.add_argument("--sourcedir", required=True)
+    args, _ = parser.parse_known_args()
+
+    shutil.copytree(args.sourcedir, args.datadir)

features/backup_restore.sh

@@ -1,21 +0,0 @@
-#!/bin/bash
-
-set -x
-
-while getopts ":-:" optchar; do
-    [[ "${optchar}" == "-" ]] || continue
-    case "${OPTARG}" in
-        datadir=* )
-            PGDATA=${OPTARG#*=}
-            ;;
-        sourcedir=* )
-            SOURCE=${OPTARG#*=}
-            ;;
-    esac
-done
-
-[[ -z $PGDATA || -z $SOURCE ]] && exit 1
-
-mkdir -p $(dirname $PGDATA)
-
-exec cp -af $SOURCE $PGDATA

features/basic_replication.feature

@@ -4,6 +4,7 @@ Feature: basic replication
   Scenario: check replication of a single table
     Given I start postgres0
     Then postgres0 is a leader after 10 seconds
+    And there is a non empty initialize key in DCS after 15 seconds
     When I issue a PATCH request to http://127.0.0.1:8008/config with {"ttl": 20, "loop_wait": 2, "synchronous_mode": true}
     Then I receive a response code 200
     When I start postgres1
@@ -27,6 +28,27 @@ Feature: basic replication
     When I issue a GET request to http://127.0.0.1:8009/async
     Then I receive a response code 200
 
+  Scenario: check multi sync replication
+    Given I issue a PATCH request to http://127.0.0.1:8008/config with {"synchronous_node_count": 2}
+    Then I receive a response code 200
+    And I sleep for 10 seconds
+    Then "sync" key in DCS has sync_standby=postgres1,postgres2 after 5 seconds
+    When I issue a GET request to http://127.0.0.1:8010/sync
+    Then I receive a response code 200
+    When I issue a GET request to http://127.0.0.1:8009/sync
+    Then I receive a response code 200
+    When I issue a PATCH request to http://127.0.0.1:8008/config with {"synchronous_node_count": 1}
+    Then I receive a response code 200
+    And I shut down postgres1
+    And I sleep for 10 seconds
+    Then "sync" key in DCS has sync_standby=postgres2 after 10 seconds
+    When I start postgres1
+    And "members/postgres1" key in DCS has state=running after 10 seconds
+    When I issue a GET request to http://127.0.0.1:8010/sync
+    Then I receive a response code 200
+    When I issue a GET request to http://127.0.0.1:8009/async
+    Then I receive a response code 200
+
   Scenario: check the basic failover in synchronous mode
     Given I run patronictl.py pause batman
     Then I receive a response returncode 0
@@ -35,10 +57,12 @@ Feature: basic replication
     And I run patronictl.py resume batman
     Then I receive a response returncode 0
     And postgres2 role is the primary after 24 seconds
+    And Response on GET http://127.0.0.1:8010/history contains recovery after 10 seconds
     When I issue a PATCH request to http://127.0.0.1:8010/config with {"synchronous_mode": null, "master_start_timeout": 0}
     Then I receive a response code 200
     When I add the table bar to postgres2
     Then table bar is present on postgres1 after 20 seconds
+    And Response on GET http://127.0.0.1:8010/config contains master_start_timeout after 10 seconds
 
   Scenario: check immediate failover when master_start_timeout=0
     Given I kill postmaster on postgres2

features/callback.py

@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+import os
+import psycopg2
+import sys
+
+
+if __name__ == '__main__':
+    if not (len(sys.argv) >= 3 and sys.argv[3] == "master"):
+        sys.exit(1)
+
+    os.environ['PGPASSWORD'] = 'zalando'
+    connection = psycopg2.connect(host='127.0.0.1', port=sys.argv[1], user='postgres')
+    cursor = connection.cursor()
+    cursor.execute("SELECT slot_name FROM pg_replication_slots WHERE slot_type = 'logical'")
+
+    with open("data/postgres0/label", "w") as label:
+        label.write(next(iter(cursor.fetchone()), ""))

features/callback.sh

@@ -1,5 +0,0 @@
-#!/bin/bash
-
-[[ "$3" == "master" ]] || exit
-
-PGPASSWORD=zalando psql -h localhost -U postgres -p $1 -w -tAc "SELECT slot_name FROM pg_replication_slots WHERE slot_type = 'logical'" >> data/postgres0/label

features/callback2.py

@@ -0,0 +1,5 @@
+#!/usr/bin/env python
+
+import sys
+with open("data/{0}/{0}_cb.log".format(sys.argv[1]), "a+") as log:
+    log.write(" ".join(sys.argv[-3:]) + "\n")

features/custom_bootstrap.feature

@@ -13,5 +13,5 @@ Scenario: make a backup and do a restore into a new cluster
     Given I add the table bar to postgres1
     And I do a backup of postgres1
     When I start postgres2 in a cluster batman2 from backup
-    Then postgres2 is a leader of batman2 after 10 seconds
+    Then postgres2 is a leader of batman2 after 30 seconds
     And table bar is present on postgres2 after 10 seconds

features/environment.py

@@ -1,11 +1,6 @@
 import abc
-import consul
 import datetime
-import etcd
-import kazoo.client
-import kazoo.exceptions
 import os
-import psutil
 import psycopg2
 import json
 import shutil
@@ -170,13 +165,19 @@ class PatroniController(AbstractController):
             config = yaml.safe_load(f)
             config.pop('etcd', None)
 
+        raft_port = os.environ.get('RAFT_PORT')
+        if raft_port:
+            os.environ['RAFT_PORT'] = str(int(raft_port) + 1)
+            config['raft'] = {'data_dir': self._output_dir, 'self_addr': 'localhost:' + os.environ['RAFT_PORT']}
+
         host = config['postgresql']['listen'].split(':')[0]
 
         config['postgresql']['listen'] = config['postgresql']['connect_address'] = '{0}:{1}'.format(host, self.__PORT)
 
         config['name'] = name
         config['postgresql']['data_dir'] = self._data_dir
-        config['postgresql']['use_unix_socket'] = True
+        config['postgresql']['use_unix_socket'] = os.name != 'nt'  # windows doesn't yet support unix-domain sockets
+        config['postgresql']['pgpass'] = os.path.join(tempfile.gettempdir(), 'pgpass_' + name)
         config['postgresql']['parameters'].update({
             'logging_collector': 'on', 'log_destination': 'csvlog', 'log_directory': self._output_dir,
             'log_filename': name + '.log', 'log_statement': 'all', 'log_min_messages': 'debug1',
@@ -249,57 +250,22 @@ class PatroniController(AbstractController):
         except Exception:
             return None
 
-    def database_is_running(self):
-        pid = self._get_pid()
-        if not pid:
-            return False
-        try:
-            os.kill(pid, 0)
-        except OSError:
-            return False
-        return True
-
     def patroni_hang(self, timeout):
         hang = ProcessHang(self._handle.pid, timeout)
         self._closables.append(hang)
         hang.start()
 
-    def checkpoint_hang(self, timeout):
-        pid = self._get_pid()
-        if not pid:
-            return False
-        proc = psutil.Process(pid)
-        for child in proc.children():
-            if 'checkpoint' in child.cmdline()[0]:
-                checkpointer = child
-                break
-        else:
-            return False
-        hang = ProcessHang(checkpointer.pid, timeout)
-        self._closables.append(hang)
-        hang.start()
-        return True
-
     def cancel_background(self):
         for obj in self._closables:
             obj.close()
         self._closables = []
 
-    def terminate_backends(self):
-        pid = self._get_pid()
-        if not pid:
-            return False
-        proc = psutil.Process(pid)
-        for p in proc.children():
-            if 'process' not in p.cmdline()[0]:
-                p.terminate()
-
     @property
     def backup_source(self):
         return 'postgres://{username}:{password}@{host}:{port}/{database}'.format(**self._replication)
 
-    def backup(self, dest='data/basebackup'):
+    def backup(self, dest=os.path.join('data', 'basebackup')):
-        subprocess.call([PatroniPoolController.BACKUP_SCRIPT, '--walmethod=none',
+        subprocess.call(PatroniPoolController.BACKUP_SCRIPT + ['--walmethod=none',
                         '--datadir=' + os.path.join(self._work_directory, dest),
                         '--dbname=' + self.backup_source])
 
@@ -375,9 +341,11 @@ class ConsulController(AbstractDcsController):
         super(ConsulController, self).__init__(context)
         os.environ['PATRONI_CONSUL_HOST'] = 'localhost:8500'
         os.environ['PATRONI_CONSUL_REGISTER_SERVICE'] = 'on'
-        self._client = consul.Consul()
         self._config_file = None
 
+        import consul
+        self._client = consul.Consul()
+
     def _start(self):
         self._config_file = self._work_directory + '.json'
         with open(self._config_file, 'wb') as f:
@@ -410,26 +378,45 @@ class ConsulController(AbstractDcsController):
         super(ConsulController, self).start(max_wait_limit)
 
 
-class EtcdController(AbstractDcsController):
+class AbstractEtcdController(AbstractDcsController):
 
     """ handles all etcd related tasks, used for the tests setup and cleanup """
 
-    def __init__(self, context):
+    def __init__(self, context, client_cls):
-        super(EtcdController, self).__init__(context)
+        super(AbstractEtcdController, self).__init__(context)
-        os.environ['PATRONI_ETCD_HOST'] = 'localhost:2379'
+        self._client_cls = client_cls
-        self._client = etcd.Client(port=2379)
 
     def _start(self):
         return subprocess.Popen(["etcd", "--debug", "--data-dir", self._work_directory],
                                 stdout=self._log, stderr=subprocess.STDOUT)
 
+    def _is_running(self):
+        from patroni.dcs.etcd import DnsCachingResolver
+        # if etcd is running, but we didn't start it
+        try:
+            self._client = self._client_cls({'host': 'localhost', 'port': 2379, 'retry_timeout': 30,
+                                             'patronictl': 1}, DnsCachingResolver())
+            return True
+        except Exception:
+            return False
+
+
+class EtcdController(AbstractEtcdController):
+
+    def __init__(self, context):
+        from patroni.dcs.etcd import EtcdClient
+        super(EtcdController, self).__init__(context, EtcdClient)
+        os.environ['PATRONI_ETCD_HOST'] = 'localhost:2379'
+
     def query(self, key, scope='batman'):
+        import etcd
         try:
             return self._client.get(self.path(key, scope)).value
         except etcd.EtcdKeyNotFound:
             return None
 
     def cleanup_service_tree(self):
+        import etcd
         try:
             self._client.delete(self.path(scope=''), recursive=True)
         except (etcd.EtcdKeyNotFound, etcd.EtcdConnectionFailed):
@@ -437,12 +424,25 @@ class EtcdController(AbstractDcsController):
         except Exception as e:
             assert False, "exception when cleaning up etcd contents: {0}".format(e)
 
-    def _is_running(self):
+
-        # if etcd is running, but we didn't start it
+class Etcd3Controller(AbstractEtcdController):
+
+    def __init__(self, context):
+        from patroni.dcs.etcd3 import Etcd3Client
+        super(Etcd3Controller, self).__init__(context, Etcd3Client)
+        os.environ['PATRONI_ETCD3_HOST'] = 'localhost:2379'
+
+    def query(self, key, scope='batman'):
+        import base64
+        response = self._client.range(self.path(key, scope))
+        for k in response.get('kvs', []):
+            return base64.b64decode(k['value']).decode('utf-8') if 'value' in k else None
+
+    def cleanup_service_tree(self):
         try:
-            return bool(self._client.machines)
+            self._client.deleteprefix(self.path(scope=''))
-        except Exception:
+        except Exception as e:
-            return False
+            assert False, "exception when cleaning up etcd contents: {0}".format(e)
 
 
 class KubernetesController(AbstractDcsController):
@@ -454,8 +454,9 @@ class KubernetesController(AbstractDcsController):
         self._label_selector = ','.join('{0}={1}'.format(k, v) for k, v in self._labels.items())
         os.environ['PATRONI_KUBERNETES_LABELS'] = json.dumps(self._labels)
         os.environ['PATRONI_KUBERNETES_USE_ENDPOINTS'] = 'true'
+        os.environ['PATRONI_KUBERNETES_BYPASS_API_SERVICE'] = 'true'
 
-        from kubernetes import client as k8s_client, config as k8s_config
+        from patroni.dcs.kubernetes import k8s_client, k8s_config
         k8s_config.load_kube_config(context='local')
         self._client = k8s_client
         self._api = self._client.CoreV1Api()
@@ -473,13 +474,13 @@ class KubernetesController(AbstractDcsController):
 
     def delete_pod(self, name):
         try:
-            self._api.delete_namespaced_pod(name, self._namespace, self._client.V1DeleteOptions())
+            self._api.delete_namespaced_pod(name, self._namespace, body=self._client.V1DeleteOptions())
-        except:
+        except Exception:
             pass
         while True:
             try:
                 self._api.read_namespaced_pod(name, self._namespace)
-            except:
+            except Exception:
                 break
 
     def query(self, key, scope='batman'):
@@ -488,22 +489,23 @@ class KubernetesController(AbstractDcsController):
             return (pod.metadata.annotations or {}).get('status', '')
         else:
             try:
-                e = self._api.read_namespaced_endpoints(scope + ('' if key == 'leader' else '-' + key), self._namespace)
+                ep = scope + {'leader': '', 'history': '-config', 'initialize': '-config'}.get(key, '-' + key)
-                if key == 'leader':
+                e = self._api.read_namespaced_endpoints(ep, self._namespace)
+                if key != 'sync':
                     return e.metadata.annotations[key]
                 else:
                     return json.dumps(e.metadata.annotations)
-            except:
+            except Exception:
                 return None
 
     def cleanup_service_tree(self):
         try:
             self._api.delete_collection_namespaced_pod(self._namespace, label_selector=self._label_selector)
-        except:
+        except Exception:
             pass
         try:
             self._api.delete_collection_namespaced_endpoints(self._namespace, label_selector=self._label_selector)
-        except:
+        except Exception:
             pass
 
         while True:
@@ -523,18 +525,22 @@ class ZooKeeperController(AbstractDcsController):
         super(ZooKeeperController, self).__init__(context, False)
         if export_env:
             os.environ['PATRONI_ZOOKEEPER_HOSTS'] = "'localhost:2181'"
+
+        import kazoo.client
         self._client = kazoo.client.KazooClient()
 
     def _start(self):
         pass  # TODO: implement later
 
     def query(self, key, scope='batman'):
+        import kazoo.exceptions
         try:
             return self._client.get(self.path(key, scope))[0].decode('utf-8')
         except kazoo.exceptions.NoNodeError:
             return None
 
     def cleanup_service_tree(self):
+        import kazoo.exceptions
         try:
             self._client.delete(self.path(scope=''), recursive=True)
         except (kazoo.exceptions.NoNodeError):
@@ -559,9 +565,52 @@ class ExhibitorController(ZooKeeperController):
         os.environ.update({'PATRONI_EXHIBITOR_HOSTS': 'localhost', 'PATRONI_EXHIBITOR_PORT': '8181'})
 
 
+class RaftController(AbstractDcsController):
+
+    CONTROLLER_ADDR = 'localhost:1234'
+
+    def __init__(self, context):
+        super(RaftController, self).__init__(context)
+        os.environ.update(PATRONI_RAFT_PARTNER_ADDRS="'" + self.CONTROLLER_ADDR + "'", RAFT_PORT='1234')
+        self._raft = None
+
+    def _start(self):
+        env = os.environ.copy()
+        del env['PATRONI_RAFT_PARTNER_ADDRS']
+        env['PATRONI_RAFT_SELF_ADDR'] = self.CONTROLLER_ADDR
+        env['PATRONI_RAFT_DATA_DIR'] = self._work_directory
+        return subprocess.Popen([sys.executable, '-m', 'coverage', 'run',
+                                '--source=patroni', '-p', 'patroni_raft_controller.py'],
+                                stdout=self._log, stderr=subprocess.STDOUT, env=env)
+
+    def query(self, key, scope='batman'):
+        ret = self._raft.get(self.path(key, scope))
+        return ret and ret['value']
+
+    def set(self, key, value):
+        self._raft.set(self.path(key), value)
+
+    def cleanup_service_tree(self):
+        from patroni.dcs.raft import KVStoreTTL
+        from pysyncobj import SyncObjConf
+
+        if self._raft:
+            self._raft.destroy()
+            self._raft._SyncObj__thread.join()
+            self.stop()
+            os.makedirs(self._work_directory)
+            self.start()
+
+        ready_event = threading.Event()
+        conf = SyncObjConf(appendEntriesUseBatch=False, dynamicMembershipChange=True, onReady=ready_event.set)
+        self._raft = KVStoreTTL(None, [self.CONTROLLER_ADDR], conf)
+        ready_event.wait()
+
+
 class PatroniPoolController(object):
 
-    BACKUP_SCRIPT = 'features/backup_create.sh'
+    BACKUP_SCRIPT = [sys.executable, 'features/backup_create.py']
+    ARCHIVE_RESTORE_SCRIPT = ' '.join((sys.executable, os.path.abspath('features/archive-restore.py')))
 
     def __init__(self, context):
         self._context = context
@@ -594,9 +643,8 @@ class PatroniPoolController(object):
         self._processes[name].start(max_wait_limit)
 
     def __getattr__(self, func):
-        if func not in ['stop', 'query', 'write_label', 'read_label', 'check_role_has_changed_to', 'add_tag_to_config',
+        if func not in ['stop', 'query', 'write_label', 'read_label', 'check_role_has_changed_to',
-                        'get_watchdog', 'database_is_running', 'checkpoint_hang', 'patroni_hang',
+                        'add_tag_to_config', 'get_watchdog', 'patroni_hang', 'backup']:
-                        'terminate_backends', 'backup']:
             raise AttributeError("PatroniPoolController instance has no attribute '{0}'".format(func))
 
         def wrapper(name, *args, **kwargs):
@@ -610,7 +658,7 @@ class PatroniPoolController(object):
         self._processes.clear()
 
     def create_and_set_output_directory(self, feature_name):
-        feature_dir = os.path.join(self.patroni_path, 'features/output', feature_name.replace(' ', '_'))
+        feature_dir = os.path.join(self.patroni_path, 'features', 'output', feature_name.replace(' ', '_'))
         if os.path.exists(feature_dir):
             shutil.rmtree(feature_dir)
         os.makedirs(feature_dir)
@@ -623,7 +671,7 @@ class PatroniPoolController(object):
             'bootstrap': {
                 'method': 'pg_basebackup',
                 'pg_basebackup': {
-                    'command': self.BACKUP_SCRIPT + ' --walmethod=stream --dbname=' + f.backup_source
+                    'command': " ".join(self.BACKUP_SCRIPT) + ' --walmethod=stream --dbname=' + f.backup_source
                 },
                 'dcs': {
                     'postgresql': {
@@ -636,8 +684,9 @@ class PatroniPoolController(object):
             'postgresql': {
                 'parameters': {
                     'archive_mode': 'on',
-                    'archive_command': 'mkdir -p {0} && test ! -f {0}/%f && cp %p {0}/%f'.format(
+                    'archive_command': (self.ARCHIVE_RESTORE_SCRIPT + ' --mode archive ' +
-                            os.path.join(self.patroni_path, 'data/wal_archive'))
+                                        '--dirname {} --filename %f --pathname %p').format(
+                                        os.path.join(self.patroni_path, 'data', 'wal_archive'))
                 },
                 'authentication': {
                     'superuser': {'password': 'zalando1'},
@@ -653,12 +702,14 @@ class PatroniPoolController(object):
             'bootstrap': {
                 'method': 'backup_restore',
                 'backup_restore': {
-                    'command': 'features/backup_restore.sh --sourcedir=' + os.path.join(self.patroni_path,
+                    'command': (sys.executable + ' features/backup_restore.py --sourcedir=' +
-                                                                                        'data/basebackup'),
+                                os.path.join(self.patroni_path, 'data', 'basebackup')),
                     'recovery_conf': {
                         'recovery_target_action': 'promote',
                         'recovery_target_timeline': 'latest',
-                        'restore_command': 'cp {0}/data/wal_archive/%f %p'.format(self.patroni_path)
+                        'restore_command': (self.ARCHIVE_RESTORE_SCRIPT + ' --mode restore ' +
+                                            '--dirname {} --filename %f --pathname %p').format(
+                                            os.path.join(self.patroni_path, 'data', 'wal_archive'))
                     }
                 }
             },

features/patroni_api.feature

@@ -8,6 +8,8 @@ Scenario: check API requests on a stand-alone server
 	Then I receive a response code 200
 	And I receive a response state running
 	And I receive a response role master
+	When I issue a GET request to http://127.0.0.1:8008/standby_leader
+	Then I receive a response code 503
 	When I issue a GET request to http://127.0.0.1:8008/health
 	Then I receive a response code 200
 	When I issue a GET request to http://127.0.0.1:8008/replica
@@ -28,10 +30,7 @@ Scenario: check API requests on a stand-alone server
 	And I receive a response text "Failover could be performed only to a specific candidate"
 
 Scenario: check local configuration reload
-	Given I issue an empty POST request to http://127.0.0.1:8008/reload
+	Given I add tag new_tag new_value to postgres0 config
-	Then I receive a response code 200
-	And I receive a response text nothing changed
-	When I add tag new_tag new_value to postgres0 config
 	And I issue an empty POST request to http://127.0.0.1:8008/reload
 	Then I receive a response code 202
 
@@ -46,6 +45,20 @@ Scenario: check dynamic configuration change via DCS
 	When I issue a GET request to http://127.0.0.1:8008/patroni
 	Then I receive a response code 200
 	And I receive a response tags {'new_tag': 'new_value'}
+	And I sleep for 4 seconds
+
+Scenario: check the scheduled restart
+	Given I issue a PATCH request to http://127.0.0.1:8008/config with {"postgresql": {"parameters": {"superuser_reserved_connections": "6"}}}
+	Then I receive a response code 200
+		And Response on GET http://127.0.0.1:8008/patroni contains pending_restart after 5 seconds
+	Given I issue a scheduled restart at http://127.0.0.1:8008 in 3 seconds with {"role": "replica"}
+	Then I receive a response code 202
+		And I sleep for 4 seconds
+		And Response on GET http://127.0.0.1:8008/patroni contains pending_restart after 10 seconds
+	Given I issue a scheduled restart at http://127.0.0.1:8008 in 3 seconds with {"restart_pending": "True"}
+	Then I receive a response code 202
+		And Response on GET http://127.0.0.1:8008/patroni does not contain pending_restart after 10 seconds
+		And postgres0 role is the primary after 10 seconds
 
 Scenario: check API requests for the primary-replica pair in the pause mode
 	Given I run patronictl.py pause batman
@@ -73,6 +86,7 @@ Scenario: check the switchover via the API in the pause mode
 	And postgres1 role is the primary after 10 seconds
 	And postgres0 role is the secondary after 10 seconds
 	And replication works from postgres1 to postgres0 after 20 seconds
+	And "members/postgres0" key in DCS has state=running after 10 seconds
 	When I issue a GET request to http://127.0.0.1:8008/master
 	Then I receive a response code 503
 	When I issue a GET request to http://127.0.0.1:8008/replica
@@ -94,6 +108,7 @@ Scenario: check the scheduled switchover
 	And postgres0 role is the primary after 10 seconds
 	And postgres1 role is the secondary after 10 seconds
 	And replication works from postgres0 to postgres1 after 25 seconds
+	And "members/postgres1" key in DCS has state=running after 10 seconds
 	When I issue a GET request to http://127.0.0.1:8008/master
 	Then I receive a response code 200
 	When I issue a GET request to http://127.0.0.1:8008/replica
@@ -102,16 +117,3 @@ Scenario: check the scheduled switchover
 	Then I receive a response code 503
 	When I issue a GET request to http://127.0.0.1:8009/replica
 	Then I receive a response code 200
-
-Scenario: check the scheduled restart
-	Given I issue a PATCH request to http://127.0.0.1:8008/config with {"postgresql": {"parameters": {"superuser_reserved_connections": "6"}}}
-	Then I receive a response code 200
-		And Response on GET http://127.0.0.1:8008/patroni contains pending_restart after 5 seconds
-	Given I issue a scheduled restart at http://127.0.0.1:8008 in 3 seconds with {"role": "replica"}
-	Then I receive a response code 202
-		And I sleep for 4 seconds
-		And Response on GET http://127.0.0.1:8008/patroni contains pending_restart after 10 seconds
-	Given I issue a scheduled restart at http://127.0.0.1:8008 in 3 seconds with {"restart_pending": "True"}
-	Then I receive a response code 202
-		And Response on GET http://127.0.0.1:8008/patroni does not contain pending_restart after 10 seconds
-

features/standby_cluster.feature

@@ -2,7 +2,7 @@ Feature: standby cluster
   Scenario: check permanent logical slots are preserved on failover/switchover
     Given I start postgres1
     Then postgres1 is a leader after 10 seconds
-    And I sleep for 3 seconds
+    And there is a non empty initialize key in DCS after 15 seconds
     When I issue a PATCH request to http://127.0.0.1:8009/config with {"loop_wait": 2, "slots": {"pm_1": {"type": "physical"}}, "postgresql": {"parameters": {"wal_level": "logical"}}}
     Then I receive a response code 200
     And Response on GET http://127.0.0.1:8009/config contains slots after 10 seconds
@@ -25,12 +25,13 @@ Feature: standby cluster
     Then postgres1 is a leader of batman1 after 10 seconds
     When I add the table foo to postgres0
     Then table foo is present on postgres1 after 20 seconds
+    And I sleep for 3 seconds
     When I issue a GET request to http://127.0.0.1:8009/master
-    Then I receive a response code 200
+    Then I receive a response code 503
     When I issue a GET request to http://127.0.0.1:8009/standby_leader
     Then I receive a response code 200
     And I receive a response role standby_leader
-    And there is a postgres1_cb.log with "on_start replica batman1\non_role_change standby_leader batman1" in postgres1 data directory
+    And there is a postgres1_cb.log with "on_role_change standby_leader batman1" in postgres1 data directory
     When I start postgres2 in a cluster batman1
     Then postgres2 role is the replica after 24 seconds
     And table foo is present on postgres2 after 20 seconds
@@ -40,7 +41,8 @@ Feature: standby cluster
     And I kill postmaster on postgres1
     Then postgres2 is replicating from postgres0 after 32 seconds
     When I issue a GET request to http://127.0.0.1:8010/master
-    Then I receive a response code 200
+    Then I receive a response code 503
+    And I sleep for 3 seconds
     When I issue a GET request to http://127.0.0.1:8010/standby_leader
     Then I receive a response code 200
     And I receive a response role standby_leader

features/steps/cascading_replication.py

@@ -13,7 +13,7 @@ def start_patroni_with_a_name_value_tag(context, name, tag_name, tag_value):
 def check_label(context, label, content, name):
     label = context.pctl.read_label(name, label)
     label = label.replace('\n', '\\n')
-    assert label == content, "{0} is not equal to {1}".format(label, content)
+    assert content in label, "{0} doesn't contain {1}".format(label, content)
 
 
 @step('I create label with "{content:w}" in {name:w} data directory')
@@ -21,7 +21,7 @@ def write_label(context, content, name):
     context.pctl.write_label(name, content)
 
 
-@step('"{name}" key in DCS has {key:w}={value:w} after {time_limit:d} seconds')
+@step('"{name}" key in DCS has {key:w}={value} after {time_limit:d} seconds')
 def check_member(context, name, key, value, time_limit):
     time_limit *= context.timeout_multiplier
     max_time = time.time() + int(time_limit)
@@ -34,3 +34,17 @@ def check_member(context, name, key, value, time_limit):
             pass
         time.sleep(1)
     assert False, "{0} does not have {1}={2} in dcs after {3} seconds".format(name, key, value, time_limit)
+
+
+@step('there is a non empty {key:w} key in DCS after {time_limit:d} seconds')
+def check_initialize(context, key, time_limit):
+    time_limit *= context.timeout_multiplier
+    max_time = time.time() + int(time_limit)
+    while time.time() < max_time:
+        try:
+            if context.dcs_ctl.query(key):
+                return
+        except Exception:
+            pass
+        time.sleep(1)
+    assert False, "There is no {0} in dcs after {1} seconds".format(key, time_limit)

features/steps/patroni_api.py

@@ -1,8 +1,6 @@
-import base64
 import json
 import os
 import parse
-import requests
 import shlex
 import subprocess
 import sys
@@ -12,8 +10,10 @@ import yaml
 from behave import register_type, step, then
 from dateutil import tz
 from datetime import datetime, timedelta
+from patroni.request import PatroniRequest
 
 tzutc = tz.tzutc()
+request_executor = PatroniRequest({'ctl': {'auth': 'username:password'}})
 
 
 @parse.with_pattern(r'https?://(?:\w|\.|:|/)+')
@@ -45,9 +45,9 @@ def sleep_for_n_seconds(context, value):
 
 
 def _set_response(context, response):
-    context.status_code = response.status_code
+    context.status_code = response.status
-    data = response.content.decode('utf-8')
+    data = response.data.decode('utf-8')
-    ct = response.headers.get('content-type', '')
+    ct = response.getheader('content-type', '')
     if ct.startswith('application/json') or\
             ct.startswith('text/yaml') or\
             ct.startswith('text/x-yaml') or\
@@ -63,13 +63,7 @@ def _set_response(context, response):
 
 @step('I issue a GET request to {url:url}')
 def do_get(context, url):
-    try:
+    do_request(context, 'GET', url, None)
-        r = requests.get(url)
-    except requests.exceptions.RequestException:
-        context.status_code = None
-        context.response = None
-    else:
-        _set_response(context, r)
 
 
 @step('I issue an empty POST request to {url:url}')
@@ -79,17 +73,11 @@ def do_post_empty(context, url):
 
 @step('I issue a {request_method:w} request to {url:url} with {data}')
 def do_request(context, request_method, url, data):
-    data = data and json.loads(data) or {}
+    data = data and json.loads(data)
-    headers = {'Authorization': 'Basic ' + base64.b64encode('username:password'.encode('utf-8')).decode('utf-8'),
-               'Content-Type': 'application/json'}
     try:
-        if request_method == 'PATCH':
+        r = request_executor.request(request_method, url, data)
-            r = requests.patch(url, headers=headers, json=data)
+    except Exception:
-        else:
+        context.status_code = context.response = None
-            r = requests.post(url, headers=headers, json=data)
-    except requests.exceptions.RequestException:
-        context.status_code = None
-        context.response = None
     else:
         _set_response(context, r)
 
@@ -149,8 +137,8 @@ def add_tag_to_config(context, tag, value, pg_name):
 def check_http_response(context, url, value, timeout, negate=False):
     timeout *= context.timeout_multiplier
     for _ in range(int(timeout)):
-        r = requests.get(url)
+        r = request_executor.request('GET', url)
-        if (value in r.content.decode('utf-8')) != negate:
+        if (value in r.data.decode('utf-8')) != negate:
             break
         time.sleep(1)
     else:

features/steps/standby_cluster.py

@@ -1,4 +1,5 @@
 import os
+import sys
 import time
 
 from behave import step
@@ -9,7 +10,8 @@ SELECT * FROM pg_catalog.pg_stat_replication
 WHERE application_name = '{0}'
 """
 
-callback = "bash -c 'echo \"${*: -3:1} ${*: -2:1} ${*: -1:1}\" >> data/$1/$1_cb.log' -- "
+executable = sys.executable if os.name != 'nt' else sys.executable.replace('\\', '/')
+callback = executable + " features/callback2.py "
 
 
 @step('I start {name:w} with callback configured')
@@ -17,7 +19,7 @@ def start_patroni_with_callbacks(context, name):
     return context.pctl.start(name, custom_config={
         "postgresql": {
             "callbacks": {
-                "on_role_change": "features/callback.sh"
+                "on_role_change": executable + " features/callback.py"
             }
         }
     })
@@ -30,8 +32,8 @@ def start_patroni(context, name, cluster_name):
         "postgresql": {
             "callbacks": {c: callback + name for c in ('on_start', 'on_stop', 'on_restart', 'on_role_change')},
             "backup_restore": {
-                "command": "features/backup_restore.sh --sourcedir=" + os.path.join(context.pctl.patroni_path,
+                "command": (executable + " features/backup_restore.py --sourcedir=" +
-                                                                                    "data/basebackup")}
+                            os.path.join(context.pctl.patroni_path, 'data', 'basebackup'))}
         }
     })
 

features/steps/watchdog.py

@@ -44,31 +44,6 @@ def watchdog_was_triggered(context, name, timeout):
     assert False
 
 
-@then('{name:w} watchdog was not triggered')
-def watchdog_was_not_triggered(context, name):
-    assert not context.pctl.get_watchdog(name).was_triggered
-
-
-@step('{name:w} checkpoint takes {timeout:d} seconds')
-def checkpoint_hang(context, name, timeout):
-    assert context.pctl.checkpoint_hang(name, timeout)
-
-
 @step('{name:w} hangs for {timeout:d} seconds')
 def patroni_hang(context, name, timeout):
     return context.pctl.patroni_hang(name, timeout)
-
-
-@step('I terminate {name:w} user processes')
-def terminate_backends(context, name):
-    return context.pctl.terminate_backends(name)
-
-
-@step('Sleep for {timeout:d} seconds')
-def dcs_connection_lost(context, timeout):
-    time.sleep(timeout)
-
-
-@then('{name:w} database is running')
-def database_is_running(context, name):
-    assert context.pctl.database_is_running(name)

kubernetes/entrypoint.sh

@@ -33,7 +33,5 @@ postgresql:
 __EOF__
 
 unset PATRONI_SUPERUSER_PASSWORD PATRONI_REPLICATION_PASSWORD
-export KUBERNETES_NAMESPACE=$PATRONI_KUBERNETES_NAMESPACE
-export POD_NAME=$PATRONI_NAME
 
 exec /usr/bin/python3 /usr/local/bin/patroni /home/postgres/patroni.yml

kubernetes/openshift-example/templates/template_patroni_ephemeral.yml

@@ -118,6 +118,8 @@ objects:
               fieldRef:
                 apiVersion: v1
                 fieldPath: metadata.namespace
+          - name: PATRONI_KUBERNETES_BYPASS_API_SERVICE
+            value: 'true'
           - name: PATRONI_KUBERNETES_LABELS
             value: '{application: ${APPLICATION_NAME}, cluster-name: ${PATRONI_CLUSTER_NAME}}'
           - name: PATRONI_SUPERUSER_USERNAME
@@ -152,6 +154,16 @@ objects:
           image: docker-registry.default.svc:5000/${NAMESPACE}/patroni:latest
           imagePullPolicy: IfNotPresent
           name: ${APPLICATION_NAME}
+          readinessProbe:
+            httpGet:
+              scheme: HTTP
+              path: /readiness
+              port: 8008
+            initialDelaySeconds: 3
+            periodSeconds: 10
+            timeoutSeconds: 5
+            successThreshold: 1
+            failureThreshold: 3
           ports:
           - containerPort: 8008
             protocol: TCP
@@ -240,6 +252,34 @@ objects:
   subjects:
   - kind: ServiceAccount
     name: ${SERVICE_ACCOUNT}
+# Following privileges are only required if deployed not in the "default"
+# namespace and you want Patroni to bypass kubernetes service
+# (PATRONI_KUBERNETES_BYPASS_API_SERVICE=true)
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRole
+  metadata:
+    name: patroni-k8s-ep-access
+  rules:
+  - apiGroups:
+    - ""
+    resources:
+    - endpoints
+    resourceNames:
+    - kubernetes
+    verbs:
+    - get
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRoleBinding
+  metadata:
+    name: ${NAMESPACE}-${SERVICE_ACCOUNT}-k8s-ep-access
+  roleRef:
+    apiGroup: rbac.authorization.k8s.io
+    kind: ClusterRole
+    name: patroni-k8s-ep-access
+  subjects:
+  - kind: ServiceAccount
+    name: ${SERVICE_ACCOUNT}
+    namespace: ${NAMESPACE}
 parameters:
 - description: The name of the application for labelling all artifacts.
   displayName: Application Name

kubernetes/openshift-example/templates/template_patroni_persistent.yaml

@@ -5,11 +5,9 @@ metadata:
   annotations:
     description: |-
       Patroni Postgresql database cluster, with persistent storage.
-
-      WARNING: Any data stored will be lost upon pod destruction. Only use this template for testing.
     iconClass: icon-postgresql
     openshift.io/display-name: Patroni Postgresql (Persistent)
-    openshift.io/long-description: This template deploys a a patroni postgresql HA cluster without persistent storage.
+    openshift.io/long-description: This template deploys a a patroni postgresql HA cluster with persistent storage.
     tags: postgresql
 objects:
 - apiVersion: v1
@@ -106,6 +104,20 @@ objects:
           application: ${APPLICATION_NAME}
           cluster-name: ${PATRONI_CLUSTER_NAME}
       spec:
+        initContainers:
+        - command:
+          - sh
+          - -c 
+          - "mkdir -p /home/postgres/pgdata/pgroot/data && chmod 0700 /home/postgres/pgdata/pgroot/data"
+          image: docker-registry.default.svc:5000/${NAMESPACE}/patroni:latest
+          imagePullPolicy: IfNotPresent
+          name: fix-perms
+          resources: {}
+          terminationMessagePath: /dev/termination-log
+          terminationMessagePolicy: File
+          volumeMounts:
+          - mountPath: /home/postgres/pgdata
+            name: ${APPLICATION_NAME}
         containers:
         - env:
           - name: PATRONI_KUBERNETES_POD_IP
@@ -118,6 +130,8 @@ objects:
               fieldRef:
                 apiVersion: v1
                 fieldPath: metadata.namespace
+          - name: PATRONI_KUBERNETES_BYPASS_API_SERVICE
+            value: 'true'
           - name: PATRONI_KUBERNETES_LABELS
             value: '{application: ${APPLICATION_NAME}, cluster-name: ${PATRONI_CLUSTER_NAME}}'
           - name: PATRONI_SUPERUSER_USERNAME
@@ -152,6 +166,16 @@ objects:
           image: docker-registry.default.svc:5000/${NAMESPACE}/patroni:latest
           imagePullPolicy: IfNotPresent
           name: ${APPLICATION_NAME}
+          readinessProbe:
+            httpGet:
+              scheme: HTTP
+              path: /readiness
+              port: 8008
+            initialDelaySeconds: 3
+            periodSeconds: 10
+            timeoutSeconds: 5
+            successThreshold: 1
+            failureThreshold: 3
           ports:
           - containerPort: 8008
             protocol: TCP
@@ -252,6 +276,34 @@ objects:
   subjects:
   - kind: ServiceAccount
     name: ${SERVICE_ACCOUNT}
+# Following privileges are only required if deployed not in the "default"
+# namespace and you want Patroni to bypass kubernetes service
+# (PATRONI_KUBERNETES_BYPASS_API_SERVICE=true)
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRole
+  metadata:
+    name: patroni-k8s-ep-access
+  rules:
+  - apiGroups:
+    - ""
+    resources:
+    - endpoints
+    resourceNames:
+    - kubernetes
+    verbs:
+    - get
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: ClusterRoleBinding
+  metadata:
+    name: ${NAMESPACE}-${SERVICE_ACCOUNT}-k8s-ep-access
+  roleRef:
+    apiGroup: rbac.authorization.k8s.io
+    kind: ClusterRole
+    name: patroni-k8s-ep-access
+  subjects:
+  - kind: ServiceAccount
+    name: ${SERVICE_ACCOUNT}
+    namespace: ${NAMESPACE}
 parameters:
 - description: The name of the application for labelling all artifacts.
   displayName: Application Name

kubernetes/patroni_k8s.yaml

@@ -10,7 +10,7 @@ spec:
   clusterIP: None
 
 ---
-apiVersion: apps/v1beta1
+apiVersion: apps/v1
 kind: StatefulSet
 metadata:
   name: &cluster_name patronidemo
@@ -31,6 +31,16 @@ spec:
       - name: *cluster_name
         image: patroni  # docker build -t patroni .
         imagePullPolicy: IfNotPresent
+        readinessProbe:
+          httpGet:
+            scheme: HTTP
+            path: /readiness
+            port: 8008
+          initialDelaySeconds: 3
+          periodSeconds: 10
+          timeoutSeconds: 5
+          successThreshold: 1
+          failureThreshold: 3
         ports:
         - containerPort: 8008
           protocol: TCP
@@ -48,6 +58,8 @@ spec:
           valueFrom:
             fieldRef:
               fieldPath: metadata.namespace
+        - name: PATRONI_KUBERNETES_BYPASS_API_SERVICE
+          value: 'true'
         - name: PATRONI_KUBERNETES_USE_ENDPOINTS
           value: 'true'
         - name: PATRONI_KUBERNETES_LABELS
@@ -123,6 +135,25 @@ spec:
   - port: 5432
     targetPort: 5432
 
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: patronidemo-repl
+  labels:
+    application: patroni
+    cluster-name:  &cluster_name patronidemo
+    role: replica
+spec:
+  type: ClusterIP
+  selector:
+    application: patroni
+    cluster-name: *cluster_name
+    role: replica
+  ports:
+  - port: 5432
+    targetPort: 5432
+
 ---
 apiVersion: v1
 kind: Secret
@@ -210,3 +241,37 @@ roleRef:
 subjects:
 - kind: ServiceAccount
   name: patronidemo
+
+# Following privileges are only required if deployed not in the "default"
+# namespace and you want Patroni to bypass kubernetes service
+# (PATRONI_KUBERNETES_BYPASS_API_SERVICE=true)
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRole
+metadata:
+  name: patroni-k8s-ep-access
+rules:
+- apiGroups:
+  - ""
+  resources:
+  - endpoints
+  resourceNames:
+  - kubernetes
+  verbs:
+  - get
+
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: patroni-k8s-ep-access
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: patroni-k8s-ep-access
+subjects:
+- kind: ServiceAccount
+  name: patronidemo
+# The namespace must be specified explicitly.
+# If deploying to the different namespace you have to change it.
+  namespace: default

patroni/__init__.py

@@ -4,33 +4,35 @@ import signal
 import sys
 import time
 
+from .daemon import AbstractPatroniDaemon, abstract_main
+from .version import __version__
+
 logger = logging.getLogger(__name__)
 
+PATRONI_ENV_PREFIX = 'PATRONI_'
+KUBERNETES_ENV_PREFIX = 'KUBERNETES_'
 
-class Patroni(object):
 
-    def __init__(self):
+class Patroni(AbstractPatroniDaemon):
+
+    def __init__(self, config):
         from patroni.api import RestApiServer
-        from patroni.config import Config
         from patroni.dcs import get_dcs
         from patroni.ha import Ha
-        from patroni.log import PatroniLogger
         from patroni.postgresql import Postgresql
-        from patroni.version import __version__
+        from patroni.request import PatroniRequest
         from patroni.watchdog import Watchdog
 
-        self.setup_signal_handlers()
+        super(Patroni, self).__init__(config)
 
         self.version = __version__
-        self.logger = PatroniLogger()
-        self.config = Config()
-        self.logger.reload_config(self.config.get('log', {}))
         self.dcs = get_dcs(self.config)
         self.watchdog = Watchdog(self.config)
         self.load_dynamic_configuration()
 
         self.postgresql = Postgresql(self.config['postgresql'])
         self.api = RestApiServer(self, self.config['restapi'])
+        self.request = PatroniRequest(self.config, True)
         self.ha = Ha(self)
 
         self.tags = self.get_tags()
@@ -66,14 +68,16 @@ class Patroni(object):
     def nosync(self):
         return bool(self.tags.get('nosync', False))
 
-    def reload_config(self):
+    def reload_config(self, sighup=False, local=False):
         try:
+            super(Patroni, self).reload_config(sighup, local)
+            if local:
                 self.tags = self.get_tags()
-            self.logger.reload_config(self.config.get('log', {}))
+                self.request.reload_config(self.config)
-            self.dcs.reload_config(self.config)
-            self.watchdog.reload_config(self.config)
                 self.api.reload_config(self.config['restapi'])
-            self.postgresql.reload_config(self.config['postgresql'])
+            self.watchdog.reload_config(self.config)
+            self.postgresql.reload_config(self.config['postgresql'], sighup)
+            self.dcs.reload_config(self.config)
         except Exception:
             logger.exception('Failed to reload config_file=%s', self.config.config_file)
 
@@ -81,15 +85,6 @@ class Patroni(object):
     def replicatefrom(self):
         return self.tags.get('replicatefrom')
 
-    def sighup_handler(self, *args):
-        self._received_sighup = True
-
-    def sigterm_handler(self, *args):
-        with self._sigterm_lock:
-            if not self._received_sigterm:
-                self._received_sigterm = True
-                sys.exit()
-
     @property
     def noloadbalance(self):
         return bool(self.tags.get('noloadbalance', False))
@@ -107,21 +102,12 @@ class Patroni(object):
         elif self.ha.watch(nap_time):
             self.next_run = time.time()
 
-    @property
-    def received_sigterm(self):
-        with self._sigterm_lock:
-            return self._received_sigterm
-
     def run(self):
         self.api.start()
         self.next_run = time.time()
+        super(Patroni, self).run()
 
-        while not self.received_sigterm:
+    def _run_cycle(self):
-            if self._received_sighup:
-                self._received_sighup = False
-                if self.config.reload_local_configuration():
-                    self.reload_config()
-
         logger.info(self.ha.run_cycle())
 
         if self.dcs.cluster and self.dcs.cluster.config and self.dcs.cluster.config.data \
@@ -133,35 +119,23 @@ class Patroni(object):
 
         self.schedule_next_run()
 
-    def setup_signal_handlers(self):
+    def _shutdown(self):
-        from threading import Lock
-
-        self._received_sighup = False
-        self._sigterm_lock = Lock()
-        self._received_sigterm = False
-        if os.name != 'nt':
-            signal.signal(signal.SIGHUP, self.sighup_handler)
-        signal.signal(signal.SIGTERM, self.sigterm_handler)
-
-    def shutdown(self):
-        with self._sigterm_lock:
-            self._received_sigterm = True
         try:
             self.api.shutdown()
         except Exception:
             logger.exception('Exception during RestApi.shutdown')
+        try:
             self.ha.shutdown()
-        self.logger.shutdown()
+        except Exception:
+            logger.exception('Exception during Ha.shutdown')
 
 
 def patroni_main():
-    patroni = Patroni()
+    from multiprocessing import freeze_support
-    try:
+    from patroni.validator import schema
-        patroni.run()
+
-    except KeyboardInterrupt:
+    freeze_support()
-        pass
+    abstract_main(Patroni, schema)
-    finally:
-        patroni.shutdown()
 
 
 def fatal(string, *args):
@@ -191,8 +165,8 @@ def check_psycopg2():
 
 
 def main():
-    check_psycopg2()
     if os.getpid() != 1:
+        check_psycopg2()
         return patroni_main()
 
     # Patroni started with PID=1, it looks like we are in the container

patroni/api.py

@@ -7,35 +7,30 @@ import traceback
 import dateutil.parser
 import datetime
 import os
+import six
 import socket
+import sys
 
-from patroni.postgresql import PostgresConnectionException
-from patroni.postgresql.misc import postgres_version_to_int, PostgresException
-from patroni.utils import deep_compare, parse_bool, patch_config, Retry, \
-    RetryFailedError, parse_int, split_host_port, tzutc, uri
 from six.moves.BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
 from six.moves.socketserver import ThreadingMixIn
+from six.moves.urllib_parse import urlparse, parse_qs
 from threading import Thread
 
+from .exceptions import PostgresConnectionException, PostgresException
+from .postgresql.misc import postgres_version_to_int
+from .utils import deep_compare, enable_keepalive, parse_bool, patch_config, Retry, \
+    RetryFailedError, parse_int, split_host_port, tzutc, uri, cluster_as_json
+
 logger = logging.getLogger(__name__)
 
 
-def check_auth(func):
-    """Decorator function to check authorization header.
-
-    Usage example:
-    @check_auth
-    def do_PUT_foo():
-        pass
-    """
-    def wrapper(handler, *args, **kwargs):
-        if handler.check_auth_header():
-            return func(handler, *args, **kwargs)
-    return wrapper
-
-
 class RestApiHandler(BaseHTTPRequestHandler):
 
+    def _write_status_code_only(self, status_code):
+        message = self.responses[status_code][0]
+        self.wfile.write('{0} {1} {2}\r\n\r\n'.format(self.protocol_version, status_code, message).encode('utf-8'))
+        self.log_request(status_code)
+
     def _write_response(self, status_code, body, content_type='text/html', headers=None):
         self.send_response(status_code)
         headers = headers or {}
@@ -43,20 +38,28 @@ class RestApiHandler(BaseHTTPRequestHandler):
             headers['Content-Type'] = content_type
         for name, value in headers.items():
             self.send_header(name, value)
+        for name, value in self.server.http_extra_headers.items():
+            self.send_header(name, value)
         self.end_headers()
         self.wfile.write(body.encode('utf-8'))
 
     def _write_json_response(self, status_code, response):
         self._write_response(status_code, json.dumps(response), content_type='application/json')
 
-    def send_auth_request(self, body):
+    def check_auth(func):
-        headers = {'WWW-Authenticate': 'Basic realm="' + self.server.patroni.__class__.__name__ + '"'}
+        """Decorator function to check authorization header or client certificates
-        self._write_response(401, body, headers=headers)
 
-    def check_auth_header(self):
+        Usage example:
-        auth_header = self.headers.get('Authorization')
+        @check_auth
-        status = self.server.check_auth_header(auth_header)
+        def do_PUT_foo():
-        return not status or self.send_auth_request(status)
+            pass
+        """
+
+        def wrapper(self, *args, **kwargs):
+            if self.server.check_auth(self):
+                return func(self, *args, **kwargs)
+
+        return wrapper
 
     def _write_status_response(self, status_code, response):
         patroni = self.server.patroni
@@ -87,59 +90,88 @@ class RestApiHandler(BaseHTTPRequestHandler):
     def do_GET(self, write_status_code_only=False):
         """Default method for processing all GET requests which can not be routed to other methods"""
 
-        time_start = time.time()
-        request_type = 'OPTIONS' if write_status_code_only else 'GET'
-
         path = '/master' if self.path == '/' else self.path
         response = self.get_postgresql_status()
 
         patroni = self.server.patroni
         cluster = patroni.dcs.cluster
 
-        if not cluster and patroni.ha.is_paused():
+        leader_optime = cluster and cluster.last_leader_operation or 0
-            primary_status_code = 200 if response['role'] == 'master' else 503
+        replayed_location = response.get('xlog', {}).get('replayed_location', 0)
-        else:
+        max_replica_lag = parse_int(self.path_query.get('lag', [sys.maxsize])[0], 'B')
-            primary_status_code = 200 if patroni.ha.is_leader() else 503
+        if max_replica_lag is None:
+            max_replica_lag = sys.maxsize
+        is_lagging = leader_optime and leader_optime > replayed_location + max_replica_lag
 
-        replica_status_code = 200 if not patroni.noloadbalance and \
+        replica_status_code = 200 if not patroni.noloadbalance and not is_lagging and \
             response.get('role') == 'replica' and response.get('state') == 'running' else 503
+
+        if not cluster and patroni.ha.is_paused():
+            primary_status_code = 200 if response.get('role') == 'master' else 503
+            standby_leader_status_code = 200 if response.get('role') == 'standby_leader' else 503
+        elif patroni.ha.is_leader():
+            if patroni.ha.is_standby_cluster():
+                primary_status_code = replica_status_code = 503
+                standby_leader_status_code = 200 if response.get('role') in ('replica', 'standby_leader') else 503
+            else:
+                primary_status_code = 200
+                standby_leader_status_code = 503
+        else:
+            primary_status_code = standby_leader_status_code = 503
+
         status_code = 503
 
-        if patroni.ha.is_standby_cluster() and ('standby_leader' in path or 'standby-leader' in path):
+        if 'standby_leader' in path or 'standby-leader' in path:
-            status_code = 200 if patroni.ha.is_leader() else 503
+            status_code = standby_leader_status_code
         elif 'master' in path or 'leader' in path or 'primary' in path or 'read-write' in path:
             status_code = primary_status_code
         elif 'replica' in path:
             status_code = replica_status_code
         elif 'read-only' in path:
-            status_code = 200 if primary_status_code == 200 else replica_status_code
+            status_code = 200 if 200 in (primary_status_code, standby_leader_status_code) else replica_status_code
         elif 'health' in path:
             status_code = 200 if response.get('state') == 'running' else 503
         elif cluster:  # dcs is available
             is_synchronous = cluster.is_synchronous_mode() and cluster.sync \
-                    and cluster.sync.sync_standby == patroni.postgresql.name
+                    and patroni.postgresql.name in cluster.sync.members
             if path in ('/sync', '/synchronous') and is_synchronous:
                 status_code = replica_status_code
             elif path in ('/async', '/asynchronous') and not is_synchronous:
                 status_code = replica_status_code
 
         if write_status_code_only:  # when haproxy sends OPTIONS request it reads only status code and nothing more
-            message = self.responses[status_code][0]
+            self._write_status_code_only(status_code)
-            self.wfile.write('{0} {1} {2}\r\n'.format(self.protocol_version, status_code, message).encode('utf-8'))
         else:
             self._write_status_response(status_code, response)
 
-        time_end = time.time()
-        self.log_message('%s %s %s latency: %s ms', request_type, path,
-                         status_code, (time_end - time_start) * 1000)
-
     def do_OPTIONS(self):
         self.do_GET(write_status_code_only=True)
 
+    def do_GET_liveness(self):
+        self._write_status_code_only(200)
+
+    def do_GET_readiness(self):
+        patroni = self.server.patroni
+        if patroni.ha.is_leader():
+            status_code = 200
+        elif patroni.postgresql.state == 'running':
+            status_code = 200 if patroni.dcs.cluster else 503
+        else:
+            status_code = 503
+        self._write_status_code_only(status_code)
+
     def do_GET_patroni(self):
         response = self.get_postgresql_status(True)
         self._write_status_response(200, response)
 
+    def do_GET_cluster(self):
+        cluster = self.server.patroni.dcs.get_cluster(True)
+        self._write_json_response(200, cluster_as_json(cluster))
+
+    def do_GET_history(self):
+        cluster = self.server.patroni.dcs.cluster or self.server.patroni.dcs.get_cluster()
+        self._write_json_response(200, cluster.history and cluster.history.lines or [])
+
     def do_GET_config(self):
         cluster = self.server.patroni.dcs.cluster or self.server.patroni.dcs.get_cluster()
         if cluster.config:
@@ -166,6 +198,8 @@ class RestApiHandler(BaseHTTPRequestHandler):
         request = self._read_json_content()
         if request:
             cluster = self.server.patroni.dcs.get_cluster()
+            if not (cluster.config and cluster.config.modify_index):
+                return self.send_error(503)
             data = cluster.config.data.copy()
             if patch_config(data, request):
                 value = json.dumps(data, separators=(',', ':'))
@@ -187,18 +221,8 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
     @check_auth
     def do_POST_reload(self):
-        try:
-            if self.server.patroni.config.reload_local_configuration(True):
-                status_code = 202
-                response = 'reload scheduled'
         self.server.patroni.sighup_handler()
-            else:
+        self._write_response(202, 'reload scheduled')
-                status_code = 200
-                response = 'nothing changed'
-        except Exception as e:
-            status_code = 500
-            response = str(e)
-        self._write_response(status_code, response)
 
     @staticmethod
     def parse_schedule(schedule, action):
@@ -292,6 +316,20 @@ class RestApiHandler(BaseHTTPRequestHandler):
             code = 404
         self._write_response(code, data)
 
+    @check_auth
+    def do_DELETE_switchover(self):
+        failover = self.server.patroni.dcs.get_cluster().failover
+        if failover and failover.scheduled_at:
+            if not self.server.patroni.dcs.manual_failover('', '', index=failover.index):
+                return self.send_error(409)
+            else:
+                data = "scheduled switchover deleted"
+                code = 200
+        else:
+            data = "no switchover is scheduled"
+            code = 404
+        self._write_response(code, data)
+
     @check_auth
     def do_POST_reinitialize(self):
         request = self._read_json_content(body_is_optional=True)
@@ -331,13 +369,13 @@ class RestApiHandler(BaseHTTPRequestHandler):
         if leader and (not cluster.leader or cluster.leader.name != leader):
             return 'leader name does not match'
         if candidate:
-            if action == 'switchover' and cluster.is_synchronous_mode() and cluster.sync.sync_standby != candidate:
+            if action == 'switchover' and cluster.is_synchronous_mode() and candidate not in cluster.sync.members:
                 return 'candidate name does not match with sync_standby'
             members = [m for m in cluster.members if m.name == candidate]
             if not members:
                 return 'candidate does not exists'
         elif cluster.is_synchronous_mode():
-            members = [m for m in cluster.members if m.name == cluster.sync.sync_standby]
+            members = [m for m in cluster.members if m.name in cluster.sync.members]
             if not members:
                 return action + ' is not possible: can not find sync_standby'
         else:
@@ -414,6 +452,9 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
         ret = BaseHTTPRequestHandler.parse_request(self)
         if ret:
+            urlpath = urlparse(self.path)
+            self.path = urlpath.path
+            self.path_query = parse_qs(urlpath.query) or {}
             mname = self.path.lstrip('/').split('/')[0]
             mname = self.command + ('_' + mname if mname else '')
             if hasattr(self, 'do_' + mname):
@@ -427,77 +468,75 @@ class RestApiHandler(BaseHTTPRequestHandler):
         return retry(self.server.query, sql, *params)
 
     def get_postgresql_status(self, retry=False):
+        postgresql = self.server.patroni.postgresql
         try:
             cluster = self.server.patroni.dcs.cluster
 
-            if self.server.patroni.postgresql.state not in ('running', 'restarting', 'starting'):
+            if postgresql.state not in ('running', 'restarting', 'starting'):
                 raise RetryFailedError('')
-            stmt = ("WITH replication_info AS ("
+            stmt = ("SELECT " + postgresql.POSTMASTER_START_TIME + ", " + postgresql.TL_LSN + ","
-                    "SELECT usename, application_name, client_addr, state, sync_state, sync_priority"
-                    " FROM pg_catalog.pg_stat_replication) SELECT"
-                    " pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
-                    " CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0"
-                    " ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
-                    "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END,"
-                    " CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0"
-                    " ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint END,"
-                    " pg_catalog.pg_{0}_{1}_diff(COALESCE(pg_catalog.pg_last_{0}_receive_{1}(),"
-                    " pg_catalog.pg_last_{0}_replay_{1}()), '0/0')::bigint,"
-                    " pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint,"
                     " pg_catalog.to_char(pg_catalog.pg_last_xact_replay_timestamp(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
-                    " pg_catalog.pg_is_in_recovery() AND pg_catalog.pg_is_{0}_replay_paused(), "
+                    " pg_catalog.array_to_json(pg_catalog.array_agg(pg_catalog.row_to_json(ri))) "
-                    "(SELECT pg_catalog.array_to_json(pg_catalog.array_agg("
+                    "FROM (SELECT (SELECT rolname FROM pg_authid WHERE oid = usesysid) AS usename,"
-                    "pg_catalog.row_to_json(ri))) FROM replication_info ri)")
+                    " application_name, client_addr, w.state, sync_state, sync_priority"
+                    " FROM pg_catalog.pg_stat_get_wal_senders() w, pg_catalog.pg_stat_get_activity(pid)) AS ri")
 
-            row = self.query(stmt.format(self.server.patroni.postgresql.wal_name,
+            row = self.query(stmt.format(postgresql.wal_name, postgresql.lsn_name), retry=retry)[0]
-                                         self.server.patroni.postgresql.lsn_name), retry=retry)[0]
 
             result = {
-                'state': self.server.patroni.postgresql.state,
+                'state': postgresql.state,
                 'postmaster_start_time': row[0],
                 'role': 'replica' if row[1] == 0 else 'master',
-                'server_version': self.server.patroni.postgresql.server_version,
+                'server_version': postgresql.server_version,
                 'cluster_unlocked': bool(not cluster or cluster.is_unlocked()),
                 'xlog': ({
-                    'received_location': row[3],
+                    'received_location': row[4] or row[3],
-                    'replayed_location': row[4],
+                    'replayed_location': row[3],
-                    'replayed_timestamp': row[5],
+                    'replayed_timestamp': row[6],
-                    'paused': row[6]} if row[1] == 0 else {
+                    'paused': row[5]} if row[1] == 0 else {
                     'location': row[2]
                 })
             }
 
             if result['role'] == 'replica' and self.server.patroni.ha.is_standby_cluster():
-                result['role'] = self.server.patroni.postgresql.role
+                result['role'] = postgresql.role
 
             if row[1] > 0:
                 result['timeline'] = row[1]
             else:
                 leader_timeline = None if not cluster or cluster.is_unlocked() else cluster.leader.timeline
-                result['timeline'] = self.server.patroni.postgresql.replica_cached_timeline(leader_timeline)
+                result['timeline'] = postgresql.replica_cached_timeline(leader_timeline)
 
             if row[7]:
                 result['replication'] = row[7]
 
             return result
         except (psycopg2.Error, RetryFailedError, PostgresConnectionException):
-            state = self.server.patroni.postgresql.state
+            state = postgresql.state
             if state == 'running':
                 logger.exception('get_postgresql_status')
                 state = 'unknown'
-            return {'state': state, 'role': self.server.patroni.postgresql.role}
+            return {'state': state, 'role': postgresql.role}
+
+    def handle_one_request(self):
+        self.__start_time = time.time()
+        BaseHTTPRequestHandler.handle_one_request(self)
 
     def log_message(self, fmt, *args):
-        logger.debug("API thread: %s - - [%s] %s", self.client_address[0], self.log_date_time_string(), fmt % args)
+        latency = 1000.0 * (time.time() - self.__start_time)
+        logger.debug("API thread: %s - - %s latency: %0.3f ms", self.client_address[0], fmt % args, latency)
 
 
 class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
+    # On 3.7+ the `ThreadingMixIn` gathers all non-daemon worker threads in order to join on them at server close.
+    daemon_threads = True  # Make worker threads "fire and forget" to prevent a memory leak.
 
     def __init__(self, patroni, config):
         self.patroni = patroni
         self.__listen = None
-        self.__initialize(config)
+        self.__ssl_options = None
-        self.__set_config_parameters(config)
+        self.http_extra_headers = {}
+        self.reload_config(config)
         self.daemon = True
 
     def query(self, sql, *params):
@@ -528,13 +567,16 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
             if not auth_header.startswith('Basic ') or not self.check_basic_auth_key(auth_header[6:]):
                 return 'not authenticated'
 
-    @staticmethod
+    def check_auth(self, rh):
-    def __get_ssl_options(config):
+        if not hasattr(rh.request, 'getpeercert') or not rh.request.getpeercert():  # valid client cert isn't present
-        return {option: config[option] for option in ['certfile', 'keyfile'] if option in config}
+            if self.__protocol == 'https' and self.__ssl_options.get('verify_client') in ('required', 'optional'):
+                return rh._write_response(403, 'client certificate required')
 
-    def __set_config_parameters(self, config):
+        reason = self.check_auth_header(rh.headers.get('Authorization'))
-        self.__auth_key = base64.b64encode(config['auth'].encode('utf-8')).decode('utf-8') if 'auth' in config else None
+        if reason:
-        self.connection_string = uri(self.__protocol, config.get('connect_address') or self.__listen, 'patroni')
+            headers = {'WWW-Authenticate': 'Basic realm="' + self.patroni.__class__.__name__ + '"'}
+            return rh._write_response(401, reason, headers=headers)
+        return True
 
     @staticmethod
     def __has_dual_stack():
@@ -553,7 +595,7 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
 
     def __httpserver_init(self, host, port):
         dual_stack = self.__has_dual_stack()
-        if host == '':
+        if host in ('', '*'):
             host = None
 
         info = socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_STREAM, 0, socket.AI_PASSIVE)
@@ -561,45 +603,84 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
         info.sort(key=lambda x: x[0] == socket.AF_INET, reverse=not dual_stack)
 
         self.address_family = info[0][0]
-        HTTPServer.__init__(self, info[0][-1][:2], RestApiHandler)
-
-    def __initialize(self, config):
         try:
-            host, port = split_host_port(config['listen'], None)
+            HTTPServer.__init__(self, info[0][-1][:2], RestApiHandler)
+        except socket.error:
+            logger.error(
+                    "Couldn't start a service on '%s:%s', please check your `restapi.listen` configuration", host, port)
+            raise
+
+    def __initialize(self, listen, ssl_options):
+        try:
+            host, port = split_host_port(listen, None)
         except Exception:
             raise ValueError('Invalid "restapi" config: expected <HOST>:<PORT> for "listen", but got "{0}"'
-                             .format(config['listen']))
+                             .format(listen))
 
-        if self.__listen is not None:  # changing config in runtime
+        reloading_config = self.__listen is not None  # changing config in runtime
+        if reloading_config:
             self.shutdown()
 
-        self.__listen = config['listen']
+        self.__listen = listen
-        self.__ssl_options = self.__get_ssl_options(config)
+        self.__ssl_options = ssl_options
 
         self.__httpserver_init(host, port)
         Thread.__init__(self, target=self.serve_forever)
         self._set_fd_cloexec(self.socket)
 
-        self.__protocol = 'http'
-
         # wrap socket with ssl if 'certfile' is defined in a config.yaml
         # Sometime it's also needed to pass reference to a 'keyfile'.
-        if self.__ssl_options.get('certfile'):
+        self.__protocol = 'https' if ssl_options.get('certfile') else 'http'
+        if self.__protocol == 'https':
             import ssl
-            ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
+            ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH, cafile=ssl_options.get('cafile'))
-            ctx.load_cert_chain(**self.__ssl_options)
+            ctx.load_cert_chain(certfile=ssl_options['certfile'], keyfile=ssl_options.get('keyfile'))
+            verify_client = ssl_options.get('verify_client')
+            if verify_client:
+                modes = {'none': ssl.CERT_NONE, 'optional': ssl.CERT_OPTIONAL, 'required': ssl.CERT_REQUIRED}
+                if verify_client in modes:
+                    ctx.verify_mode = modes[verify_client]
+                else:
+                    logger.error('Bad value in the "restapi.verify_client": %s', verify_client)
             self.socket = ctx.wrap_socket(self.socket, server_side=True)
-            self.__protocol = 'https'
+        if reloading_config:
-        return True
+            self.start()
+
+    def process_request_thread(self, request, client_address):
+        if isinstance(request, tuple):
+            sock, newsock = request
+            try:
+                request = sock.context.wrap_socket(newsock, do_handshake_on_connect=sock.do_handshake_on_connect,
+                                                   suppress_ragged_eofs=sock.suppress_ragged_eofs, server_side=True)
+            except socket.error:
+                return
+        super(RestApiServer, self).process_request_thread(request, client_address)
+
+    def get_request(self):
+        sock = self.socket
+        newsock, addr = socket.socket.accept(sock)
+        enable_keepalive(newsock, 10, 3)
+        if hasattr(sock, 'context'):  # SSLSocket, we want to do the deferred handshake from a thread
+            newsock = (sock, newsock)
+        return newsock, addr
 
     def reload_config(self, config):
         if 'listen' not in config:  # changing config in runtime
             raise ValueError('Can not find "restapi.listen" config')
 
-        elif (self.__listen != config['listen'] or self.__ssl_options != self.__get_ssl_options(config)) \
+        ssl_options = {n: config[n] for n in ('certfile', 'keyfile', 'cafile') if n in config}
-                and self.__initialize(config):
+
-            self.start()
+        self.http_extra_headers = config.get('http_extra_headers') or {}
-        self.__set_config_parameters(config)
+        self.http_extra_headers.update((config.get('https_extra_headers') or {}) if ssl_options.get('certfile') else {})
+
+        if isinstance(config.get('verify_client'), six.string_types):
+            ssl_options['verify_client'] = config['verify_client'].lower()
+
+        if self.__listen != config['listen'] or self.__ssl_options != ssl_options:
+            self.__initialize(config['listen'], ssl_options)
+
+        self.__auth_key = base64.b64encode(config['auth'].encode('utf-8')).decode('utf-8') if 'auth' in config else None
+        self.connection_string = uri(self.__protocol, config.get('connect_address') or self.__listen, 'patroni')
 
     @staticmethod
     def handle_error(request, client_address):

patroni/async_executor.py

@@ -110,6 +110,12 @@ class AsyncExecutor(object):
     def run_async(self, func, args=()):
         Thread(target=self.run, args=(func, args)).start()
 
+    def try_run_async(self, action, func, args=()):
+        prev = self.schedule(action)
+        if prev is None:
+            return self.run_async(func, args)
+        return 'Failed to run {0}, {1} is already in progress'.format(action, prev)
+
     def cancel(self):
         with self:
             with self._scheduled_action_lock:

patroni/config.py

@@ -2,19 +2,36 @@ import json
 import logging
 import os
 import shutil
-import sys
 import tempfile
 import yaml
 
 from collections import defaultdict
 from copy import deepcopy
+from patroni import PATRONI_ENV_PREFIX
+from patroni.exceptions import ConfigParseError
 from patroni.dcs import ClusterConfig
-from patroni.postgresql.config import ConfigHandler
+from patroni.postgresql.config import CaseInsensitiveDict, ConfigHandler
 from patroni.utils import deep_compare, parse_bool, parse_int, patch_config
-from requests.structures import CaseInsensitiveDict
 
 logger = logging.getLogger(__name__)
 
+_AUTH_ALLOWED_PARAMETERS = (
+    'username',
+    'password',
+    'sslmode',
+    'sslcert',
+    'sslkey',
+    'sslrootcert',
+    'sslcrl',
+    'gssencmode',
+    'channel_binding'
+)
+
+
+def default_validator(conf):
+    if not conf:
+        return "Config is empty."
+
 
 class Config(object):
     """
@@ -36,7 +53,6 @@ class Config(object):
          to work with it as with the old `config` object.
     """
 
-    PATRONI_ENV_PREFIX = 'PATRONI_'
     PATRONI_CONFIG_VARIABLE = PATRONI_ENV_PREFIX + 'CONFIGURATION'
 
     __CACHE_FILENAME = 'patroni.dynamic.json'
@@ -45,8 +61,10 @@ class Config(object):
         'maximum_lag_on_failover': 1048576,
         'check_timeline': False,
         'master_start_timeout': 300,
+        'master_stop_timeout': 0,
         'synchronous_mode': False,
         'synchronous_mode_strict': False,
+        'synchronous_node_count': 1,
         'standby_cluster': {
             'create_replica_methods': '',
             'host': '',
@@ -59,34 +77,34 @@ class Config(object):
         'postgresql': {
             'bin_dir': '',
             'use_slots': True,
-            'parameters': CaseInsensitiveDict({p: v[0] for p, v in ConfigHandler.CMDLINE_OPTIONS.items()})
+            'parameters': CaseInsensitiveDict({p: v[0] for p, v in ConfigHandler.CMDLINE_OPTIONS.items()
+                                               if p not in ('wal_keep_segments', 'wal_keep_size')})
         },
         'watchdog': {
             'mode': 'automatic',
         }
     }
 
-    def __init__(self):
+    def __init__(self, configfile, validator=default_validator):
         self._modify_index = -1
         self._dynamic_configuration = {}
 
         self.__environment_configuration = self._build_environment_configuration()
 
         # Patroni reads the configuration from the command-line argument if it exists, otherwise from the environment
-        self._config_file = len(sys.argv) >= 2 and os.path.isfile(sys.argv[1]) and sys.argv[1]
+        self._config_file = configfile and os.path.exists(configfile) and configfile
         if self._config_file:
             self._local_configuration = self._load_config_file()
         else:
             config_env = os.environ.pop(self.PATRONI_CONFIG_VARIABLE, None)
             self._local_configuration = config_env and yaml.safe_load(config_env) or self.__environment_configuration
-            if not self._local_configuration:
+        if validator:
-                print('Usage: {0} config.yml'.format(sys.argv[0]))
+            error = validator(self._local_configuration)
-                print('\tPatroni may also read the configuration from the {0} environment variable'.
+            if error:
-                      format(self.PATRONI_CONFIG_VARIABLE))
+                raise ConfigParseError(error)
-                sys.exit(1)
 
         self.__effective_configuration = self._build_effective_configuration({}, self._local_configuration)
-        self._data_dir = self.__effective_configuration['postgresql']['data_dir']
+        self._data_dir = self.__effective_configuration.get('postgresql', {}).get('data_dir', "")
         self._cache_file = os.path.join(self._data_dir, self.__CACHE_FILENAME)
         self._load_cache()
         self._cache_needs_saving = False
@@ -102,10 +120,30 @@ class Config(object):
     def check_mode(self, mode):
         return bool(parse_bool(self._dynamic_configuration.get(mode)))
 
+    def _load_config_path(self, path):
+        """
+        If path is a file, loads the yml file pointed to by path.
+        If path is a directory, loads all yml files in that directory in alphabetical order
+        """
+        if os.path.isfile(path):
+            files = [path]
+        elif os.path.isdir(path):
+            files = [os.path.join(path, f) for f in sorted(os.listdir(path))
+                     if (f.endswith('.yml') or f.endswith('.yaml')) and os.path.isfile(os.path.join(path, f))]
+        else:
+            logger.error('config path %s is neither directory nor file', path)
+            raise ConfigParseError('invalid config path')
+
+        overall_config = {}
+        for fname in files:
+            with open(fname) as f:
+                config = yaml.safe_load(f)
+                patch_config(overall_config, config)
+        return overall_config
+
     def _load_config_file(self):
         """Loads config.yaml from filesystem and applies some values which were set via ENV"""
-        with open(self._config_file) as f:
+        config = self._load_config_path(self._config_file)
-            config = yaml.safe_load(f)
         patch_config(config, self.__environment_configuration)
         return config
 
@@ -158,23 +196,19 @@ class Config(object):
             except Exception:
                 logger.exception('Exception when setting dynamic_configuration')
 
-    def reload_local_configuration(self, dry_run=False):
+    def reload_local_configuration(self):
         if self.config_file:
             try:
                 configuration = self._load_config_file()
                 if not deep_compare(self._local_configuration, configuration):
                     new_configuration = self._build_effective_configuration(self._dynamic_configuration, configuration)
-                    if dry_run:
-                        return not deep_compare(new_configuration, self.__effective_configuration)
                     self._local_configuration = configuration
                     self.__effective_configuration = new_configuration
                     return True
                 else:
-                    logger.info('No configuration items changed, nothing to reload.')
+                    logger.info('No local configuration items changed.')
             except Exception:
                 logger.exception('Exception when reloading local configuration from %s', self.config_file)
-                if dry_run:
-                    raise
 
     @staticmethod
     def _process_postgresql_parameters(parameters, is_local=False):
@@ -208,7 +242,7 @@ class Config(object):
         ret = defaultdict(dict)
 
         def _popenv(name):
-            return os.environ.pop(Config.PATRONI_ENV_PREFIX + name.upper(), None)
+            return os.environ.pop(PATRONI_ENV_PREFIX + name.upper(), None)
 
         for param in ('name', 'namespace', 'scope'):
             value = _popenv(param)
@@ -217,7 +251,7 @@ class Config(object):
 
         def _fix_log_env(name, oldname):
             value = _popenv(oldname)
-            name = Config.PATRONI_ENV_PREFIX + 'LOG_' + name.upper()
+            name = PATRONI_ENV_PREFIX + 'LOG_' + name.upper()
             if value and name not in os.environ:
                 os.environ[name] = value
 
@@ -230,9 +264,11 @@ class Config(object):
                 if value:
                     ret[section][param] = value
 
-        _set_section_values('restapi', ['listen', 'connect_address', 'certfile', 'keyfile'])
+        _set_section_values('restapi', ['listen', 'connect_address', 'certfile', 'keyfile', 'cafile', 'verify_client',
+                                        'http_extra_headers', 'https_extra_headers'])
+        _set_section_values('ctl', ['insecure', 'cacert', 'certfile', 'keyfile'])
         _set_section_values('postgresql', ['listen', 'connect_address', 'config_dir', 'data_dir', 'pgpass', 'bin_dir'])
-        _set_section_values('log', ['level', 'format', 'dateformat', 'max_queue_size',
+        _set_section_values('log', ['level', 'traceback_level', 'format', 'dateformat', 'max_queue_size',
                                     'dir', 'file_size', 'file_num', 'loggers'])
 
         def _parse_dict(value):
@@ -250,9 +286,9 @@ class Config(object):
             if value:
                 ret['log']['loggers'] = value
 
-        def _get_auth(name):
+        def _get_auth(name, params=None):
             ret = {}
-            for param in ('username', 'password'):
+            for param in params or _AUTH_ALLOWED_PARAMETERS[:2]:
                 value = _popenv(name + '_' + param)
                 if value:
                     ret[param] = value
@@ -264,7 +300,7 @@ class Config(object):
 
         authentication = {}
         for user_type in ('replication', 'superuser', 'rewind'):
-            entry = _get_auth(user_type)
+            entry = _get_auth(user_type, _AUTH_ALLOWED_PARAMETERS)
             if entry:
                 authentication[user_type] = entry
 
@@ -280,14 +316,19 @@ class Config(object):
                 logger.exception('Exception when parsing list %s', value)
                 return None
 
+        _set_section_values('raft', ['data_dir', 'self_addr', 'partner_addrs'])
+        if 'raft' in ret and 'partner_addrs' in ret['raft']:
+            ret['raft']['partner_addrs'] = _parse_list(ret['raft']['partner_addrs'])
+
         for param in list(os.environ.keys()):
-            if param.startswith(Config.PATRONI_ENV_PREFIX):
+            if param.startswith(PATRONI_ENV_PREFIX):
                 # PATRONI_(ETCD|CONSUL|ZOOKEEPER|EXHIBITOR|...)_(HOSTS?|PORT|..)
                 name, suffix = (param[8:].split('_', 1) + [''])[:2]
                 if suffix in ('HOST', 'HOSTS', 'PORT', 'USE_PROXIES', 'PROTOCOL', 'SRV', 'URL', 'PROXY',
                               'CACERT', 'CERT', 'KEY', 'VERIFY', 'TOKEN', 'CHECKS', 'DC', 'CONSISTENCY',
                               'REGISTER_SERVICE', 'SERVICE_CHECK_INTERVAL', 'NAMESPACE', 'CONTEXT',
-                              'USE_ENDPOINTS', 'SCOPE_LABEL', 'ROLE_LABEL', 'POD_IP', 'PORTS', 'LABELS') and name:
+                              'USE_ENDPOINTS', 'SCOPE_LABEL', 'ROLE_LABEL', 'POD_IP', 'PORTS', 'LABELS',
+                              'BYPASS_API_SERVICE', 'KEY_PASSWORD', 'USE_SSL') and name:
                     value = os.environ.pop(param)
                     if suffix == 'PORT':
                         value = value and parse_int(value)
@@ -295,16 +336,17 @@ class Config(object):
                         value = value and _parse_list(value)
                     elif suffix == 'LABELS':
                         value = _parse_dict(value)
-                    elif suffix in ('USE_PROXIES', 'REGISTER_SERVICE'):
+                    elif suffix in ('USE_PROXIES', 'REGISTER_SERVICE', 'BYPASS_API_SERVICE'):
                         value = parse_bool(value)
                     if value:
                         ret[name.lower()][suffix.lower()] = value
-        if 'etcd' in ret:
+        for dcs in ('etcd', 'etcd3'):
-            ret['etcd'].update(_get_auth('etcd'))
+            if dcs in ret:
+                ret[dcs].update(_get_auth(dcs))
 
         users = {}
         for param in list(os.environ.keys()):
-            if param.startswith(Config.PATRONI_ENV_PREFIX):
+            if param.startswith(PATRONI_ENV_PREFIX):
                 name, suffix = (param[8:].rsplit('_', 1) + [''])[:2]
                 # PATRONI_<username>_PASSWORD=<password>, PATRONI_<username>_OPTIONS=<option1,option2,...>
                 # CREATE USER "<username>" WITH <OPTIONS> PASSWORD '<password>'
@@ -334,7 +376,7 @@ class Config(object):
                 config[name] = deepcopy(value) if value else {}
 
         # restapi server expects to get restapi.auth = 'username:password'
-        if 'authentication' in config['restapi']:
+        if 'restapi' in config and 'authentication' in config['restapi']:
             config['restapi']['auth'] = '{username}:{password}'.format(**config['restapi']['authentication'])
 
         # special treatment for old config
@@ -353,6 +395,11 @@ class Config(object):
         if 'superuser' not in pg_config['authentication'] and 'pg_rewind' in pg_config:
             pg_config['authentication']['superuser'] = pg_config['pg_rewind']
 
+        # handle setting additional connection parameters that may be available
+        # in the configuration file, such as SSL connection parameters
+        for name, value in pg_config['authentication'].items():
+            pg_config['authentication'][name] = {n: v for n, v in value.items() if n in _AUTH_ALLOWED_PARAMETERS}
+
         # no 'name' in config
         if 'name' not in config and 'name' in pg_config:
             config['name'] = pg_config['name']
@@ -363,6 +410,7 @@ class Config(object):
             'retry_timeout',
             'synchronous_mode',
             'synchronous_mode_strict',
+            'synchronous_node_count',
         )
 
         pg_config.update({p: config[p] for p in updated_fields if p in config})

patroni/ctl.py

@@ -2,11 +2,11 @@
 Patroni Control
 '''
 
-import base64
 import click
 import codecs
 import datetime
 import dateutil.parser
+import dateutil.tz
 import cdiff
 import copy
 import difflib
@@ -15,26 +15,25 @@ import json
 import logging
 import os
 import random
-import requests
+import six
 import subprocess
 import sys
 import tempfile
 import time
-import tzlocal
 import yaml
 
 from click import ClickException
+from collections import defaultdict
 from contextlib import contextmanager
-from patroni.config import Config
 from patroni.dcs import get_dcs as _get_dcs
 from patroni.exceptions import PatroniException
 from patroni.postgresql import Postgresql
 from patroni.postgresql.misc import postgres_version_to_int
-from patroni.utils import patch_config, polling_loop
+from patroni.utils import cluster_as_json, patch_config, polling_loop
+from patroni.request import PatroniRequest
 from patroni.version import __version__
-from prettytable import PrettyTable
+from prettytable import ALL, FRAME, PrettyTable
 from six.moves.urllib_parse import urlparse
-from six import text_type
 
 CONFIG_DIR_PATH = click.get_app_dir('patroni')
 CONFIG_FILE_PATH = os.path.join(CONFIG_DIR_PATH, 'patronictl.yaml')
@@ -48,14 +47,42 @@ class PatroniCtlException(ClickException):
     pass
 
 
+class PatronictlPrettyTable(PrettyTable):
+
+    def __init__(self, header, *args, **kwargs):
+        PrettyTable.__init__(self, *args, **kwargs)
+        self.__table_header = header
+        self.__hline_num = 0
+        self.__hline = None
+
+    def _is_first_hline(self):
+        return self.__hline_num == 0
+
+    def _set_hline(self, value):
+        self.__hline = value
+
+    def _get_hline(self):
+        ret = self.__hline
+
+        # Inject nice table header
+        if self._is_first_hline() and self.__table_header:
+            header = self.__table_header[:len(ret) - 2]
+            ret = "".join([ret[0], header, ret[1 + len(header):]])
+
+        self.__hline_num += 1
+        return ret
+
+    _hrule = property(_get_hline, _set_hline)
+
+
 def parse_dcs(dcs):
     if dcs is None:
         return None
+    elif '//' not in dcs:
+        dcs = '//' + dcs
 
     parsed = urlparse(dcs)
     scheme = parsed.scheme
-    if scheme == '' and parsed.netloc == '':
-        parsed = urlparse('//' + dcs)
     port = int(parsed.port) if parsed.port else None
 
     if scheme == '':
@@ -68,21 +95,17 @@ def parse_dcs(dcs):
 
 
 def load_config(path, dcs):
+    from patroni.config import Config
+
     if not (os.path.exists(path) and os.access(path, os.R_OK)):
+        if path != CONFIG_FILE_PATH:    # bail if non-default config location specified but file not found / readable
+            raise PatroniCtlException('Provided config file {0} not existing or no read rights.'
+                                      ' Check the -c/--config-file parameter'.format(path))
+        else:
             logging.debug('Ignoring configuration file "%s". It does not exists or is not readable.', path)
     else:
         logging.debug('Loading configuration from file %s', path)
-    config = {}
+    config = Config(path, validator=None).copy()
-    old_argv = list(sys.argv)
-    try:
-        sys.argv[1] = path
-        if Config.PATRONI_CONFIG_VARIABLE not in os.environ:
-            for p in ('PATRONI_RESTAPI_LISTEN', 'PATRONI_POSTGRESQL_DATA_DIR'):
-                if p not in os.environ:
-                    os.environ[p] = '.'
-        config = Config().copy()
-    finally:
-        sys.argv = old_argv
 
     dcs = parse_dcs(dcs) or parse_dcs(config.get('dcs_api')) or {}
     if dcs:
@@ -100,7 +123,7 @@ def store_config(config, path):
         yaml.dump(config, fd)
 
 
-option_format = click.option('--format', '-f', 'fmt', help='Output format (pretty, json, yaml)', default='pretty')
+option_format = click.option('--format', '-f', 'fmt', help='Output format (pretty, tsv, json, yaml)', default='pretty')
 option_watchrefresh = click.option('-w', '--watch', type=float, help='Auto update the screen every X seconds')
 option_watch = click.option('-W', is_flag=True, help='Auto update the screen every 2 seconds')
 option_force = click.option('--force', is_flag=True, help='Do not ask for confirmation at any point')
@@ -135,63 +158,42 @@ def get_dcs(config, scope):
         raise PatroniCtlException(str(e))
 
 
-def auth_header(config):
+def request_patroni(member, method='GET', endpoint=None, data=None):
-    if config.get('restapi', {}).get('auth', ''):
-        return {'Authorization': 'Basic ' + base64.b64encode(config['restapi']['auth'].encode('utf-8')).decode('utf-8')}
-
-
-def request_patroni(member, request_type, endpoint, content=None, headers=None):
     ctx = click.get_current_context()  # the current click context
-    headers = headers or {}
+    request_executor = ctx.obj.get('__request_patroni')
-    url_parts = urlparse(member.api_url)
+    if not request_executor:
-    logging.debug(url_parts)
+        request_executor = ctx.obj['__request_patroni'] = PatroniRequest(ctx.obj)
-    if 'Content-Type' not in headers:
+    return request_executor(member, method, endpoint, data)
-        headers['Content-Type'] = 'application/json'
-
-    url = '{0}://{1}/{2}'.format(url_parts.scheme, url_parts.netloc, endpoint)
-
-    insecure = ctx.obj.get('ctl', {}).get('insecure', False)
-    # Get certfile if any from several configuration namespace
-    cert = ctx.obj.get('ctl', {}).get('cacert') or \
-        ctx.obj.get('restapi', {}).get('cacert') or \
-        ctx.obj.get('restapi', {}).get('certfile')
-    # In the case we specificaly disable SSL cert verification we don't want to have the warning
-    if insecure:
-        verify = False
-    elif cert:
-        verify = cert
-    else:
-        verify = True
-    return getattr(requests, request_type)(url, headers=headers,
-                                           data=json.dumps(content) if content else None, timeout=60,
-                                           verify=verify)
 
 
-def print_output(columns, rows=None, alignment=None, fmt='pretty', header=True, delimiter='\t'):
+def print_output(columns, rows, alignment=None, fmt='pretty', header=None, delimiter='\t'):
-    rows = rows or []
+    if fmt in {'json', 'yaml', 'yml'}:
-    if fmt == 'pretty':
+        elements = [{k: v for k, v in zip(columns, r) if not header or str(v)} for r in rows]
-        t = PrettyTable(columns)
+        func = json.dumps if fmt == 'json' else format_config_for_editing
-        for k, v in (alignment or {}).items():
+        click.echo(func(elements))
-            t.align[k] = v
+    elif fmt in {'pretty', 'tsv', 'topology'}:
-        for r in rows:
+        list_cluster = bool(header and columns and columns[0] == 'Cluster')
-            t.add_row(r)
+        if list_cluster and 'Tags' in columns:  # we want to format member tags as YAML
-        click.echo(t)
+            i = columns.index('Tags')
-        return
+            for row in rows:
-
+                if row[i]:
-    if fmt in ['json', 'yaml', 'yml']:
+                    row[i] = format_config_for_editing(row[i], fmt != 'pretty').strip()
-        elements = [dict(zip(columns, r)) for r in rows]
+        if list_cluster and fmt != 'tsv':  # skip cluster name if pretty-printing
-        if fmt == 'json':
+            columns = columns[1:] if columns else []
-            click.echo(json.dumps(elements))
+            rows = [row[1:] for row in rows]
-        elif fmt in ('yaml', 'yml'):
-            click.echo(yaml.safe_dump(elements, encoding=None, default_flow_style=False, allow_unicode=True, width=200))
 
         if fmt == 'tsv':
-        if columns is not None and header:
+            for r in ([columns] if columns else []) + rows:
-            click.echo(delimiter.join(columns))
+                click.echo(delimiter.join(map(str, r)))
-
+        else:
+            hrules = ALL if any(any(isinstance(c, six.string_types) and '\n' in c for c in r) for r in rows) else FRAME
+            table = PatronictlPrettyTable(header, columns, hrules=hrules)
+            table.align = 'l'
+            for k, v in (alignment or {}).items():
+                table.align[k] = v
             for r in rows:
-            c = [str(c) for c in r]
+                table.add_row(r)
-            click.echo(delimiter.join(c))
+            click.echo(table)
 
 
 def watching(w, watch, max_count=None, clear=True):
@@ -224,7 +226,7 @@ def watching(w, watch, max_count=None, clear=True):
 
 def get_all_members(cluster, role='master'):
     if role == 'master':
-        if cluster.leader is not None:
+        if cluster.leader is not None and cluster.leader.name:
             yield cluster.leader
         return
 
@@ -241,6 +243,15 @@ def get_any_member(cluster, role='master', member=None):
             return m
 
 
+def get_all_members_leader_first(cluster):
+    leader_name = cluster.leader.member.name if cluster.leader and cluster.leader.member.api_url else None
+    if leader_name:
+        yield cluster.leader.member
+    for member in cluster.members:
+        if member.api_url and member.name != leader_name:
+            yield member
+
+
 def get_cursor(cluster, connect_parameters, role='master', member=None):
     member = get_any_member(cluster, role=role, member=member)
     if member is None:
@@ -271,10 +282,12 @@ def get_cursor(cluster, connect_parameters, role='master', member=None):
     return None
 
 
-def get_members(cluster, cluster_name, member_names, role, force, action, scheduled_at=None):
+def get_members(cluster, cluster_name, member_names, role, force, action, ask_confirmation=True):
     candidates = {m.name: m for m in cluster.members}
 
     if not force or role:
+        if not member_names and not candidates:
+            raise PatroniCtlException('{0} cluster doesn\'t have any members'.format(cluster_name))
         output_members(cluster, cluster_name)
 
     if role:
@@ -294,21 +307,26 @@ def get_members(cluster, cluster_name, member_names, role, force, action, schedu
         if member_name not in candidates:
             raise PatroniCtlException('{0} is not a member of cluster'.format(member_name))
 
+    members = [candidates[n] for n in member_names]
+    if ask_confirmation:
+        confirm_members_action(members, force, action)
+    return members
+
+
+def confirm_members_action(members, force, action, scheduled_at=None):
     if scheduled_at:
         if not force:
             confirm = click.confirm('Are you sure you want to schedule {0} of members {1} at {2}?'
-                                    .format(action, ', '.join(member_names), scheduled_at))
+                                    .format(action, ', '.join([m.name for m in members]), scheduled_at))
             if not confirm:
                 raise PatroniCtlException('Aborted scheduled {0}'.format(action))
     else:
         if not force:
             confirm = click.confirm('Are you sure you want to {0} members {1}?'
-                                    .format(action, ', '.join(member_names)))
+                                    .format(action, ', '.join([m.name for m in members])))
             if not confirm:
                 raise PatroniCtlException('Aborted {0}'.format(action))
 
-    return [candidates[n] for n in member_names]
-
 
 @ctl.command('dsn', help='Generate a dsn for the provided member, defaults to a dsn of the master')
 @click.option('--role', '-r', help='Give a dsn of any member with this role', type=click.Choice(['master', 'replica',
@@ -333,8 +351,7 @@ def dsn(obj, cluster_name, role, member):
 
 @ctl.command('query', help='Query a Patroni PostgreSQL member')
 @arg_cluster_name
-@option_format
+@click.option('--format', 'fmt', help='Output format (pretty, tsv, json, yaml)', default='tsv')
-@click.option('--format', 'fmt', help='Output format (pretty, json)', default='tsv')
 @click.option('--file', '-f', 'p_file', help='Execute the SQL commands from this file', type=click.File('rb'))
 @click.option('--password', help='force password prompt', is_flag=True)
 @click.option('-U', '--username', help='database user name', type=str)
@@ -391,8 +408,8 @@ def query(
         if cursor is None:
             cluster = dcs.get_cluster()
 
-        output, cursor = query_member(cluster, cursor, member, role, command, connect_parameters)
+        output, header = query_member(cluster, cursor, member, role, command, connect_parameters)
-        print_output(None, output, fmt=fmt, delimiter=delimiter)
+        print_output(header, output, fmt=fmt, delimiter=delimiter)
 
 
 def query_member(cluster, cursor, member, role, command, connect_parameters):
@@ -409,15 +426,8 @@ def query_member(cluster, cursor, member, role, command, connect_parameters):
             logging.debug(message)
             return [[timestamp(0), message]], None
 
-        cursor.execute('SELECT pg_catalog.pg_is_in_recovery()')
-        in_recovery = cursor.fetchone()[0]
-
-        if in_recovery and role == 'master' or not in_recovery and role == 'replica':
-            cursor.connection.close()
-            return None, None
-
         cursor.execute(command)
-        return cursor.fetchall(), cursor
+        return cursor.fetchall(), [d.name for d in cursor.description]
     except (psycopg2.OperationalError, psycopg2.DatabaseError) as oe:
         logging.debug(oe)
         if cursor is not None and not cursor.connection.closed:
@@ -457,9 +467,9 @@ def remove(obj, cluster_name, fmt):
 
 
 def check_response(response, member_name, action_name, silent_success=False):
-    if response.status_code >= 400:
+    if response.status >= 400:
         click.echo('Failed: {0} for member {1}, status code={2}, ({3})'.format(
-            action_name, member_name, response.status_code, response.text
+            action_name, member_name, response.status, response.data.decode('utf-8')
         ))
         return False
     elif not silent_success:
@@ -472,7 +482,7 @@ def parse_scheduled(scheduled):
         try:
             scheduled_at = dateutil.parser.parse(scheduled)
             if scheduled_at.tzinfo is None:
-                scheduled_at = tzlocal.get_localzone().localize(scheduled_at)
+                scheduled_at = scheduled_at.replace(tzinfo=dateutil.tz.tzlocal())
         except (ValueError, TypeError):
             message = 'Unable to parse scheduled timestamp ({0}). It should be in an unambiguous format (e.g. ISO 8601)'
             raise PatroniCtlException(message.format(scheduled))
@@ -493,18 +503,17 @@ def reload(obj, cluster_name, member_names, force, role):
 
     members = get_members(cluster, cluster_name, member_names, role, force, 'reload')
 
-    content = {}
     for member in members:
-        r = request_patroni(member, 'post', 'reload', content, auth_header(obj))
+        r = request_patroni(member, 'post', 'reload')
-        if r.status_code == 200:
+        if r.status == 200:
             click.echo('No changes to apply on member {0}'.format(member.name))
-        elif r.status_code == 202:
+        elif r.status == 202:
             click.echo('Reload request received for member {0} and will be processed within {1} seconds'.format(
                 member.name, cluster.config.data.get('loop_wait'))
             )
         else:
             click.echo('Failed: reload for member {0}, status code={1}, ({2})'.format(
-                member.name, r.status_code, r.text)
+                member.name, r.status, r.data.decode('utf-8'))
             )
 
 
@@ -526,14 +535,15 @@ def reload(obj, cluster_name, member_names, force, role):
 def restart(obj, cluster_name, member_names, force, role, p_any, scheduled, version, pending, timeout):
     cluster = get_dcs(obj, cluster_name).get_cluster()
 
+    members = get_members(cluster, cluster_name, member_names, role, force, 'restart', False)
     if scheduled is None and not force:
         next_hour = (datetime.datetime.now() + datetime.timedelta(hours=1)).strftime('%Y-%m-%dT%H:%M')
         scheduled = click.prompt('When should the restart take place (e.g. ' + next_hour + ') ',
                                  type=str, default='now')
 
     scheduled_at = parse_scheduled(scheduled)
+    confirm_members_action(members, force, 'restart', scheduled_at)
 
-    members = get_members(cluster, cluster_name, member_names, role, force, 'restart', scheduled_at)
     if p_any:
         random.shuffle(members)
         members = members[:1]
@@ -565,19 +575,19 @@ def restart(obj, cluster_name, member_names, force, role, p_any, scheduled, vers
     for member in members:
         if 'schedule' in content:
             if force and member.data.get('scheduled_restart'):
-                r = request_patroni(member, 'delete', 'restart', headers=auth_header(obj))
+                r = request_patroni(member, 'delete', 'restart')
                 check_response(r, member.name, 'flush scheduled restart', True)
 
-        r = request_patroni(member, 'post', 'restart', content, auth_header(obj))
+        r = request_patroni(member, 'post', 'restart', content)
-        if r.status_code == 200:
+        if r.status == 200:
             click.echo('Success: restart on member {0}'.format(member.name))
-        elif r.status_code == 202:
+        elif r.status == 202:
             click.echo('Success: restart scheduled on member {0}'.format(member.name))
-        elif r.status_code == 409:
+        elif r.status == 409:
             click.echo('Failed: another restart is already scheduled on member {0}'.format(member.name))
         else:
             click.echo('Failed: restart for member {0}, status code={1}, ({2})'.format(
-                member.name, r.status_code, r.text)
+                member.name, r.status, r.data.decode('utf-8'))
             )
 
 
@@ -585,20 +595,39 @@ def restart(obj, cluster_name, member_names, force, role, p_any, scheduled, vers
 @click.argument('cluster_name')
 @click.argument('member_names', nargs=-1)
 @option_force
+@click.option('--wait', help='Wait until reinitialization completes', is_flag=True)
 @click.pass_obj
-def reinit(obj, cluster_name, member_names, force):
+def reinit(obj, cluster_name, member_names, force, wait):
     cluster = get_dcs(obj, cluster_name).get_cluster()
     members = get_members(cluster, cluster_name, member_names, None, force, 'reinitialize')
 
+    wait_on_members = []
     for member in members:
         body = {'force': force}
         while True:
-            r = request_patroni(member, 'post', 'reinitialize', body, auth_header(obj))
+            r = request_patroni(member, 'post', 'reinitialize', body)
-            if not check_response(r, member.name, 'reinitialize') and r.text.endswith(' already in progress') \
+            started = check_response(r, member.name, 'reinitialize')
+            if not started and r.data.endswith(b' already in progress') \
                     and not force and click.confirm('Do you want to cancel it and reinitialize anyway?'):
                 body['force'] = True
                 continue
             break
+        if started and wait:
+            wait_on_members.append(member)
+
+    last_display = []
+    while wait_on_members:
+        if wait_on_members != last_display:
+            click.echo('Waiting for reinitialize to complete on: {0}'.format(
+                ", ".join(member.name for member in wait_on_members))
+            )
+            last_display[:] = wait_on_members
+        time.sleep(2)
+        for member in wait_on_members:
+            data = json.loads(request_patroni(member, 'get', 'patroni').data.decode('utf-8'))
+            if data.get('state') != 'creating replica':
+                click.echo('Reinitialize is completed on: {0}'.format(member.name))
+                wait_on_members.remove(member)
 
 
 def _do_failover_or_switchover(obj, action, cluster_name, master, candidate, force, scheduled=None):
@@ -612,7 +641,7 @@ def _do_failover_or_switchover(obj, action, cluster_name, master, candidate, for
     dcs = get_dcs(obj, cluster_name)
     cluster = dcs.get_cluster()
 
-    if action == 'switchover' and cluster.leader is None:
+    if action == 'switchover' and (cluster.leader is None or not cluster.leader.name):
         raise PatroniCtlException('This cluster has no master')
 
     if master is None:
@@ -682,19 +711,19 @@ def _do_failover_or_switchover(obj, action, cluster_name, master, candidate, for
     try:
         member = cluster.leader.member if cluster.leader else cluster.get_member(candidate, False)
 
-        r = request_patroni(member, 'post', action, failover_value, auth_header(obj))
+        r = request_patroni(member, 'post', action, failover_value)
 
         # probably old patroni, which doesn't support switchover yet
-        if r.status_code == 501 and action == 'switchover' and 'Server does not support this operation' in r.text:
+        if r.status == 501 and action == 'switchover' and b'Server does not support this operation' in r.data:
-            r = request_patroni(member, 'post', 'failover', failover_value, auth_header(obj))
+            r = request_patroni(member, 'post', 'failover', failover_value)
 
-        if r.status_code in (200, 202):
+        if r.status in (200, 202):
             logging.debug(r)
             cluster = dcs.get_cluster()
             logging.debug(cluster)
-            click.echo('{0} {1}'.format(timestamp(), r.text))
+            click.echo('{0} {1}'.format(timestamp(), r.data.decode('utf-8')))
         else:
-            click.echo('{0} failed, details: {1}, {2}'.format(action.title(), r.status_code, r.text))
+            click.echo('{0} failed, details: {1}, {2}'.format(action.title(), r.status, r.data.decode('utf-8')))
             return
     except Exception:
         logging.exception(r)
@@ -728,83 +757,84 @@ def switchover(obj, cluster_name, master, candidate, force, scheduled):
     _do_failover_or_switchover(obj, 'switchover', cluster_name, master, candidate, force, scheduled)
 
 
+def generate_topology(level, member, topology):
+    members = topology.get(member['name'], [])
+
+    if level > 0:
+        member['name'] = '{0}+ {1}'.format((' ' * (level - 1) * 2), member['name'])
+
+    if member['name']:
+        yield member
+
+    for member in members:
+        for member in generate_topology(level + 1, member, topology):
+            yield member
+
+
+def topology_sort(members):
+    topology = defaultdict(list)
+    leader = next((m for m in members if m['role'].endswith('leader')), {'name': None})
+    replicas = set(member['name'] for member in members if not member['role'].endswith('leader'))
+    for member in members:
+        if not member['role'].endswith('leader'):
+            parent = member.get('tags', {}).get('replicatefrom')
+            parent = parent if parent and parent != member['name'] and parent in replicas else leader['name']
+            topology[parent].append(member)
+    for member in generate_topology(0, leader, topology):
+        yield member
+
+
 def output_members(cluster, name, extended=False, fmt='pretty'):
     rows = []
     logging.debug(cluster)
-    leader_name = None
+    initialize = {None: 'uninitialized', '': 'initializing'}.get(cluster.initialize, cluster.initialize)
-    if cluster.leader:
+    cluster = cluster_as_json(cluster)
-        leader_name = cluster.leader.name
-
-    xlog_location_cluster = cluster.last_leader_operation or 0
-
-    # Mainly for consistent pretty printing and watching we sort the output
-    cluster.members.sort(key=lambda x: x.name)
-
-    has_scheduled_restarts = any(m.data.get('scheduled_restart') for m in cluster.members)
-    has_pending_restarts = any(m.data.get('pending_restart') for m in cluster.members)
-
-    # Show Host as 'host:port' if somebody is running on non-standard port or two nodes are running on the same host
-    append_port = any(str(m.conn_kwargs()['port']) != '5432' for m in cluster.members) or\
-        len(set(m.conn_kwargs()['host'] for m in cluster.members)) < len(cluster.members)
-
-    for m in cluster.members:
-        logging.debug(m)
-
-        role = ''
-        if m.name == leader_name:
-            role = 'Leader'
-        elif m.name == cluster.sync.sync_standby:
-            role = 'Sync standby'
-
-        xlog_location = m.data.get('xlog_location')
-        lag = ''
-        if xlog_location is None:
-            lag = 'unknown'
-        elif xlog_location_cluster >= xlog_location:
-            lag = round((xlog_location_cluster - xlog_location)/1024/1024)
-
-        host = m.conn_kwargs()['host']
-        if append_port:
-            host += ':{0}'.format(m.conn_kwargs()['port'])
-
-        row = [name, m.name, host, role, m.data.get('state', ''), m.data.get('timeline', ''), lag]
-
-        if extended or has_pending_restarts:
-            row.append('*' if m.data.get('pending_restart') else '')
-
-        if extended or has_scheduled_restarts:
-            value = ''
-            scheduled_restart = m.data.get('scheduled_restart')
-            if scheduled_restart:
-                value = scheduled_restart['schedule']
-                if 'postgres_version' in scheduled_restart:
-                    value += ' if version < {0}'.format(scheduled_restart['postgres_version'])
-
-            row.append(value)
-
-        rows.append(row)
 
     columns = ['Cluster', 'Member', 'Host', 'Role', 'State', 'TL', 'Lag in MB']
-    alignment = {'Lag in MB': 'r', 'TL': 'r'}
+    for c in ('Pending restart', 'Scheduled restart', 'Tags'):
+        if extended or any(m.get(c.lower().replace(' ', '_')) for m in cluster['members']):
+            columns.append(c)
 
-    if extended or has_pending_restarts:
+    # Show Host as 'host:port' if somebody is running on non-standard port or two nodes are running on the same host
-        columns.append('Pending restart')
+    members = [m for m in cluster['members'] if 'host' in m]
+    append_port = any('port' in m and m['port'] != 5432 for m in members) or\
+        len(set(m['host'] for m in members)) < len(members)
 
-    if extended or has_scheduled_restarts:
+    sort = topology_sort if fmt == 'topology' else iter
-        columns.append('Scheduled restart')
+    for m in sort(cluster['members']):
+        logging.debug(m)
 
-    print_output(columns, rows, alignment, fmt)
+        lag = m.get('lag', '')
+        m.update(cluster=name, member=m['name'], host=m.get('host', ''), tl=m.get('timeline', ''),
+                 role=m['role'].replace('_', ' ').title(),
+                 lag_in_mb=round(lag/1024/1024) if isinstance(lag, six.integer_types) else lag,
+                 pending_restart='*' if m.get('pending_restart') else '')
+
+        if append_port and m['host'] and m.get('port'):
+            m['host'] = ':'.join([m['host'], str(m['port'])])
+
+        if 'scheduled_restart' in m:
+            value = m['scheduled_restart']['schedule']
+            if 'postgres_version' in m['scheduled_restart']:
+                value += ' if version < {0}'.format(m['scheduled_restart']['postgres_version'])
+            m['scheduled_restart'] = value
+
+        rows.append([m.get(n.lower().replace(' ', '_'), '') for n in columns])
+
+    print_output(columns, rows, {'Lag in MB': 'r', 'TL': 'r'}, fmt, ' Cluster: {0} ({1}) '.format(name, initialize))
+
+    if fmt not in ('pretty', 'topology'):  # Omit service info when using machine-readable formats
+        return
 
     service_info = []
-    if cluster.is_paused():
+    if cluster.get('pause'):
         service_info.append('Maintenance mode: on')
 
-    if cluster.failover and cluster.failover.scheduled_at:
+    if 'scheduled_switchover' in cluster:
-        info = 'Switchover scheduled at: ' + cluster.failover.scheduled_at.isoformat()
+        info = 'Switchover scheduled at: ' + cluster['scheduled_switchover']['at']
-        if cluster.failover.leader:
+        for name in ('from', 'to'):
-            info += '\n                    from: ' + cluster.failover.leader
+            if name in cluster['scheduled_switchover']:
-        if cluster.failover.candidate:
+                info += '\n{0:>24}: {1}'.format(name, cluster['scheduled_switchover'][name])
-            info += '\n                      to: ' + cluster.failover.candidate
         service_info.append(info)
 
     if service_info:
@@ -837,6 +867,16 @@ def members(obj, cluster_names, fmt, watch, w, extended, ts):
             output_members(cluster, cluster_name, extended, fmt)
 
 
+@ctl.command('topology', help='Prints ASCII topology for given cluster')
+@click.argument('cluster_names', nargs=-1)
+@option_watch
+@option_watchrefresh
+@click.pass_obj
+@click.pass_context
+def topology(ctx, obj, cluster_names, watch, w):
+    ctx.forward(members, fmt='topology')
+
+
 def timestamp(precision=6):
     return datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S.%f')[:precision - 7]
 
@@ -904,25 +944,45 @@ def scaffold(obj, cluster_name, sysid):
     click.echo("Cluster {0} has been created successfully".format(cluster_name))
 
 
-@ctl.command('flush', help='Flush scheduled events')
+@ctl.command('flush', help='Discard scheduled events')
 @click.argument('cluster_name')
 @click.argument('member_names', nargs=-1)
-@click.argument('target', type=click.Choice(['restart']))
+@click.argument('target', type=click.Choice(['restart', 'switchover']))
 @click.option('--role', '-r', help='Flush only members with this role', default='any',
               type=click.Choice(['master', 'replica', 'any']))
 @option_force
 @click.pass_obj
 def flush(obj, cluster_name, member_names, force, role, target):
-    cluster = get_dcs(obj, cluster_name).get_cluster()
+    dcs = get_dcs(obj, cluster_name)
+    cluster = dcs.get_cluster()
 
-    members = get_members(cluster, cluster_name, member_names, role, force, 'flush')
-    for member in members:
     if target == 'restart':
+        for member in get_members(cluster, cluster_name, member_names, role, force, 'flush'):
             if member.data.get('scheduled_restart'):
-                r = request_patroni(member, 'delete', 'restart', None, auth_header(obj))
+                r = request_patroni(member, 'delete', 'restart')
                 check_response(r, member.name, 'flush scheduled restart')
             else:
                 click.echo('No scheduled restart for member {0}'.format(member.name))
+    elif target == 'switchover':
+        failover = cluster.failover
+        if not failover or not failover.scheduled_at:
+            return click.echo('No pending scheduled switchover')
+        for member in get_all_members_leader_first(cluster):
+            try:
+                r = request_patroni(member, 'delete', 'switchover')
+                if r.status in (200, 404):
+                    prefix = 'Success' if r.status == 200 else 'Failed'
+                    return click.echo('{0}: {1}'.format(prefix, r.data.decode('utf-8')))
+            except Exception as err:
+                logging.warning(str(err))
+                logging.warning('Member %s is not accessible', member.name)
+
+            click.echo('Failed: member={0}, status_code={1}, ({2})'.format(
+                member.name, r.status, r.data.decode('utf-8')))
+
+        logging.warning('Failing over to DCS')
+        click.echo('{0} Could not find any accessible member of cluster {1}'.format(timestamp(), cluster_name))
+        dcs.manual_failover('', '', index=failover.index)
 
 
 def wait_until_pause_is_applied(dcs, paused, old_cluster):
@@ -949,27 +1009,22 @@ def toggle_pause(config, cluster_name, paused, wait):
     if cluster.is_paused() == paused:
         raise PatroniCtlException('Cluster is {0} paused'.format(paused and 'already' or 'not'))
 
-    members = []
+    for member in get_all_members_leader_first(cluster):
-    if cluster.leader:
-        members.append(cluster.leader.member)
-    members.extend([m for m in cluster.members if m.api_url and (not members or members[0].name != m.name)])
-
-    for member in members:
         try:
-            r = request_patroni(member, 'patch', 'config', {'pause': paused or None}, auth_header(config))
+            r = request_patroni(member, 'patch', 'config', {'pause': paused or None})
         except Exception as err:
             logging.warning(str(err))
             logging.warning('Member %s is not accessible', member.name)
             continue
 
-        if r.status_code == 200:
+        if r.status == 200:
             if wait:
                 wait_until_pause_is_applied(dcs, paused, cluster)
             else:
                 click.echo('Success: cluster management is {0}'.format(paused and 'paused' or 'resumed'))
         else:
             click.echo('Failed: {0} cluster management status code={1}, ({2})'.format(
-                       paused and 'pause' or 'resume', r.status_code, r.text))
+                       paused and 'pause' or 'resume', r.status, r.data.decode('utf-8')))
         break
     else:
         raise PatroniCtlException('Can not find accessible cluster member')
@@ -1016,7 +1071,7 @@ def show_diff(before_editing, after_editing):
     If the output is to a tty the diff will be colored. Inputs are expected to be unicode strings.
     """
     def listify(string):
-        return [l+'\n' for l in string.rstrip('\n').split('\n')]
+        return [line + '\n' for line in string.rstrip('\n').split('\n')]
 
     unified_diff = difflib.unified_diff(listify(before_editing), listify(after_editing))
 
@@ -1024,7 +1079,7 @@ def show_diff(before_editing, after_editing):
         buf = io.StringIO()
         for line in unified_diff:
             # Force cast to unicode as difflib on Python 2.7 returns a mix of unicode and str.
-            buf.write(text_type(line))
+            buf.write(six.text_type(line))
         buf.seek(0)
 
         class opts:
@@ -1037,12 +1092,12 @@ def show_diff(before_editing, after_editing):
             click.echo(line.rstrip('\n'))
 
 
-def format_config_for_editing(data):
+def format_config_for_editing(data, default_flow_style=False):
     """Formats configuration as YAML for human consumption.
 
     :param data: configuration as nested dictionaries
     :returns unicode YAML of the configuration"""
-    return yaml.safe_dump(data, default_flow_style=False, encoding=None, allow_unicode=True)
+    return yaml.safe_dump(data, default_flow_style=default_flow_style, encoding=None, allow_unicode=True, width=200)
 
 
 def apply_config_changes(before_editing, data, kvpairs):
@@ -1233,8 +1288,8 @@ def version(obj, cluster_name, member_names):
         if m.api_url:
             if not member_names or m.name in member_names:
                 try:
-                    response = request_patroni(m, 'get', 'patroni')
+                    response = request_patroni(m)
-                    data = response.json()
+                    data = json.loads(response.data.decode('utf-8'))
                     version = data.get('patroni', {}).get('version')
                     pg_version = data.get('server_version')
                     pg_version_str = " PostgreSQL {0}".format(format_pg_version(pg_version)) if pg_version else ""
@@ -1243,6 +1298,19 @@ def version(obj, cluster_name, member_names):
                     click.echo("{0}: failed to get version: {1}".format(m.name, e))
 
 
+@ctl.command('history', help="Show the history of failovers/switchovers")
+@arg_cluster_name
+@option_format
+@click.pass_obj
+def history(obj, cluster_name, fmt):
+    cluster = get_dcs(obj, cluster_name).get_cluster()
+    history = cluster.history and cluster.history.lines or []
+    for line in history:
+        if len(line) < 4:
+            line.append('')
+    print_output(['TL', 'LSN', 'Reason', 'Timestamp'], history, {'TL': 'r', 'LSN': 'r'}, fmt)
+
+
 def format_pg_version(version):
     if version < 100000:
         return "{0}.{1}.{2}".format(version // 10000, version // 100 % 100, version % 100)

patroni/daemon.py

@@ -0,0 +1,104 @@
+import abc
+import os
+import signal
+import six
+import sys
+
+from threading import Lock
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AbstractPatroniDaemon(object):
+
+    def __init__(self, config):
+        from patroni.log import PatroniLogger
+
+        self.setup_signal_handlers()
+
+        self.logger = PatroniLogger()
+        self.config = config
+        AbstractPatroniDaemon.reload_config(self, local=True)
+
+    def sighup_handler(self, *args):
+        self._received_sighup = True
+
+    def sigterm_handler(self, *args):
+        with self._sigterm_lock:
+            if not self._received_sigterm:
+                self._received_sigterm = True
+                sys.exit()
+
+    def setup_signal_handlers(self):
+        self._received_sighup = False
+        self._sigterm_lock = Lock()
+        self._received_sigterm = False
+        if os.name != 'nt':
+            signal.signal(signal.SIGHUP, self.sighup_handler)
+        signal.signal(signal.SIGTERM, self.sigterm_handler)
+
+    @property
+    def received_sigterm(self):
+        with self._sigterm_lock:
+            return self._received_sigterm
+
+    def reload_config(self, sighup=False, local=False):
+        if local:
+            self.logger.reload_config(self.config.get('log', {}))
+
+    @abc.abstractmethod
+    def _run_cycle(self):
+        """_run_cycle"""
+
+    def run(self):
+        self.logger.start()
+        while not self.received_sigterm:
+            if self._received_sighup:
+                self._received_sighup = False
+                self.reload_config(True, self.config.reload_local_configuration())
+
+            self._run_cycle()
+
+    @abc.abstractmethod
+    def _shutdown(self):
+        """_shutdown"""
+
+    def shutdown(self):
+        with self._sigterm_lock:
+            self._received_sigterm = True
+        self._shutdown()
+        self.logger.shutdown()
+
+
+def abstract_main(cls, validator=None):
+    import argparse
+
+    from .config import Config, ConfigParseError
+    from .version import __version__
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--version', action='version', version='%(prog)s {0}'.format(__version__))
+    if validator:
+        parser.add_argument('--validate-config', action='store_true', help='Run config validator and exit')
+    parser.add_argument('configfile', nargs='?', default='',
+                        help='Patroni may also read the configuration from the {0} environment variable'
+                        .format(Config.PATRONI_CONFIG_VARIABLE))
+    args = parser.parse_args()
+    try:
+        if validator and args.validate_config:
+            Config(args.configfile, validator=validator)
+            sys.exit()
+
+        config = Config(args.configfile)
+    except ConfigParseError as e:
+        if e.value:
+            print(e.value)
+        parser.print_help()
+        sys.exit(1)
+
+    controller = cls(config)
+    try:
+        controller.run()
+    except KeyboardInterrupt:
+        pass
+    finally:
+        controller.shutdown()

patroni/dcs/__init__.py

@@ -13,7 +13,7 @@ import time
 
 from collections import defaultdict, namedtuple
 from copy import deepcopy
-from patroni.exceptions import PatroniException
+from patroni.exceptions import PatroniFatalException
 from patroni.utils import parse_bool, uri
 from random import randint
 from six.moves.urllib_parse import urlparse, urlunparse, parse_qsl
@@ -66,33 +66,44 @@ def dcs_modules():
     module_prefix = __package__ + '.'
 
     if getattr(sys, 'frozen', False):
-        importer = pkgutil.get_importer(dcs_dirname)
+        toc = set()
-        return [module for module in list(importer.toc) if module.startswith(module_prefix) and module.count('.') == 2]
+        for importer in pkgutil.iter_importers(dcs_dirname):
+            if hasattr(importer, 'toc'):
+                toc |= importer.toc
+        return [module for module in toc if module.startswith(module_prefix) and module.count('.') == 2]
     else:
         return [module_prefix + name for _, name, is_pkg in pkgutil.iter_modules([dcs_dirname]) if not is_pkg]
 
 
 def get_dcs(config):
-    available_implementations = set()
+    modules = dcs_modules()
-    for module_name in dcs_modules():
+
+    for module_name in modules:
+        name = module_name.split('.')[-1]
+        if name in config:  # we will try to import only modules which have configuration section in the config file
             try:
                 module = importlib.import_module(module_name)
-            for name in filter(lambda name: not name.startswith('__'), dir(module)):  # iterate through module content
+                for key, item in module.__dict__.items():  # iterate through the module content
-                item = getattr(module, name)
-                name = name.lower()
                     # try to find implementation of AbstractDCS interface, class name must match with module_name
-                if inspect.isclass(item) and issubclass(item, AbstractDCS) and __package__ + '.' + name == module_name:
+                    if key.lower() == name and inspect.isclass(item) and issubclass(item, AbstractDCS):
-                    available_implementations.add(name)
-                    if name in config:  # which has configuration section in the config file
                         # propagate some parameters
                         config[name].update({p: config[p] for p in ('namespace', 'name', 'scope', 'loop_wait',
                                              'patronictl', 'ttl', 'retry_timeout') if p in config})
                         return item(config[name])
             except ImportError:
-            if not config.get('patronictl'):
+                logger.debug('Failed to import %s', module_name)
+
+    available_implementations = []
+    for module_name in modules:
+        name = module_name.split('.')[-1]
+        try:
+            module = importlib.import_module(module_name)
+            available_implementations.extend(name for key, item in module.__dict__.items() if key.lower() == name
+                                             and inspect.isclass(item) and issubclass(item, AbstractDCS))
+        except ImportError:
             logger.info('Failed to import %s', module_name)
-    raise PatroniException("""Can not find suitable configuration of distributed configuration store
+    raise PatroniFatalException("""Can not find suitable configuration of distributed configuration store
-Available implementations: """ + ', '.join(available_implementations))
+Available implementations: """ + ', '.join(sorted(set(available_implementations))))
 
 
 class Member(namedtuple('Member', 'index,name,session,data')):
@@ -129,10 +140,10 @@ class Member(namedtuple('Member', 'index,name,session,data')):
     @property
     def conn_url(self):
         conn_url = self.data.get('conn_url')
-        conn_kwargs = self.data.get('conn_kwargs')
         if conn_url:
             return conn_url
 
+        conn_kwargs = self.data.get('conn_kwargs')
         if conn_kwargs:
             conn_url = uri('postgresql', (conn_kwargs.get('host'), conn_kwargs.get('port', 5432)))
             self.data['conn_url'] = conn_url
@@ -140,16 +151,19 @@ class Member(namedtuple('Member', 'index,name,session,data')):
 
     def conn_kwargs(self, auth=None):
         defaults = {
-            "host": "",
+            "host": None,
-            "port": "",
+            "port": None,
-            "database": ""
+            "database": None
         }
         ret = self.data.get('conn_kwargs')
         if ret:
             defaults.update(ret)
             ret = defaults
         else:
-            r = urlparse(self.conn_url)
+            conn_url = self.conn_url
+            if not conn_url:
+                return {}  # due to the invalid conn_url we don't care about authentication parameters
+            r = urlparse(conn_url)
             ret = {
                 'host': r.hostname,
                 'port': r.port or 5432,
@@ -157,11 +171,11 @@ class Member(namedtuple('Member', 'index,name,session,data')):
             }
             self.data['conn_kwargs'] = ret.copy()
 
+        # apply any remaining authentication parameters
         if auth and isinstance(auth, dict):
+            ret.update({k: v for k, v in auth.items() if v is not None})
             if 'username' in auth:
-                ret['user'] = auth['username']
+                ret['user'] = ret.pop('username')
-            if 'password' in auth:
-                ret['password'] = auth['password']
         return ret
 
     @property
@@ -232,21 +246,25 @@ class Leader(namedtuple('Leader', 'index,session,member')):
     def conn_url(self):
         return self.member.conn_url
 
+    @property
+    def data(self):
+        return self.member.data
+
     @property
     def timeline(self):
-        return self.member.data.get('timeline')
+        return self.data.get('timeline')
 
     @property
     def checkpoint_after_promote(self):
         """
         >>> Leader(1, '', Member.from_node(1, '', '', '{"version":"z"}')).checkpoint_after_promote
         """
-        version = self.member.data.get('version')
+        version = self.data.get('version')
         if version:
             try:
                 # 1.5.6 is the last version which doesn't expose checkpoint_after_promote: false
                 if tuple(map(int, version.split('.'))) > (1, 5, 6):
-                    return self.member.data['role'] == 'master' and 'checkpoint_after_promote' not in self.member.data
+                    return self.data['role'] == 'master' and 'checkpoint_after_promote' not in self.data
             except Exception:
                 logger.debug('Failed to parse Patroni version %s', version)
 
@@ -323,13 +341,17 @@ class ClusterConfig(namedtuple('ClusterConfig', 'index,data,modify_index')):
                 self.data.get('permanent_slots') or self.data.get('slots')
         ) or {}
 
+    @property
+    def max_timelines_history(self):
+        return self.data.get('max_timelines_history', 0)
+
 
 class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
     """Immutable object (namedtuple) which represents last observed synhcronous replication state
 
     :param index: modification index of a synchronization key in a Configuration Store
     :param leader: reference to member that was leader
-    :param sync_standby: standby that was last synchronized to leader
+    :param sync_standby: synchronous standby list (comma delimited) which are last synchronized to leader
     """
 
     @staticmethod
@@ -361,15 +383,22 @@ class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
             data = {}
         return SyncState(index, data.get('leader'), data.get('sync_standby'))
 
+    @property
+    def members(self):
+        """ Returns sync_standby in list """
+        return self.sync_standby and self.sync_standby.split(',') or []
+
     def matches(self, name):
         """
         Returns if a node name matches one of the nodes in the sync state
 
-        >>> s = SyncState(1, 'foo', 'bar')
+        >>> s = SyncState(1, 'foo', 'bar,zoo')
         >>> s.matches('foo')
         True
         >>> s.matches('bar')
         True
+        >>> s.matches('zoo')
+        True
         >>> s.matches('baz')
         False
         >>> s.matches(None)
@@ -377,7 +406,7 @@ class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
         >>> SyncState(1, None, None).matches('foo')
         False
         """
-        return name is not None and name in (self.leader, self.sync_standby)
+        return name is not None and name in [self.leader] + self.members
 
 
 class TimelineHistory(namedtuple('TimelineHistory', 'index,value,lines')):
@@ -437,19 +466,21 @@ class Cluster(namedtuple('Cluster', 'initialize,config,leader,last_leader_operat
     def is_synchronous_mode(self):
         return self.check_mode('synchronous_mode')
 
-    def get_replication_slots(self, name, role):
+    def get_replication_slots(self, my_name, role):
         # if the replicatefrom tag is set on the member - we should not create the replication slot for it on
         # the current master, because that member would replicate from elsewhere. We still create the slot if
         # the replicatefrom destination member is currently not a member of the cluster (fallback to the
         # master), or if replicatefrom destination member happens to be the current master
+        use_slots = self.config and self.config.data.get('postgresql', {}).get('use_slots', True)
         if role in ('master', 'standby_leader'):
-            slot_members = [m.name for m in self.members if m.name != name and
+            slot_members = [m.name for m in self.members if use_slots and m.name != my_name and
-                            (m.replicatefrom is None or m.replicatefrom == name or
+                            (m.replicatefrom is None or m.replicatefrom == my_name or
                              not self.has_member(m.replicatefrom))]
             permanent_slots = (self.config and self.config.permanent_slots or {}).copy()
         else:
             # only manage slots for replicas that replicate from this one, except for the leader among them
-            slot_members = [m.name for m in self.members if m.replicatefrom == name and m.name != self.leader.name]
+            slot_members = [m.name for m in self.members if use_slots and
+                            m.replicatefrom == my_name and m.name != self.leader.name]
             permanent_slots = {}
 
         slots = {slot_name_from_member_name(name): {'type': 'physical'} for name in slot_members}
@@ -470,21 +501,21 @@ class Cluster(namedtuple('Cluster', 'initialize,config,leader,last_leader_operat
                 logger.error("Slot name may only contain lower case letters, numbers, and the underscore chars")
                 continue
 
-            if name in slots:
+            value = deepcopy(value) if value else {'type': 'physical'}
-                logger.error("Permanent replication slot {'%s': %s} is conflicting with" +
-                             " physical replication slot for cluster member", name, value)
-                continue
-
-            value = deepcopy(value)
-            if not value:
-                value = {'type': 'physical'}
-
             if isinstance(value, dict):
                 if 'type' not in value:
                     value['type'] = 'logical' if value.get('database') and value.get('plugin') else 'physical'
 
-                if value['type'] == 'physical' or value['type'] == 'logical' \
+                if value['type'] == 'physical':
-                        and value.get('database') and value.get('plugin'):
+                    # Don't try to create permanent physical replication slot for yourself
+                    if name != slot_name_from_member_name(my_name):
+                        slots[name] = value
+                    continue
+                elif value['type'] == 'logical' and value.get('database') and value.get('plugin'):
+                    if name in slots:
+                        logger.error("Permanent logical replication slot {'%s': %s} is conflicting with" +
+                                     " physical replication slot for cluster member", name, value)
+                    else:
                         slots[name] = value
                     continue
 
@@ -619,7 +650,12 @@ class AbstractDCS(object):
            If the current node was running as a master and exception raised,
            instance would be demoted."""
 
-    def get_cluster(self):
+    def _bypass_caches(self):
+        """Used only in zookeeper"""
+
+    def get_cluster(self, force=False):
+        if force:
+            self._bypass_caches()
         try:
             cluster = self._load_cluster()
         except Exception:
@@ -735,10 +771,19 @@ class AbstractDCS(object):
         otherwise it should return `!False`"""
 
     @abc.abstractmethod
-    def delete_leader(self):
+    def _delete_leader(self):
-        """Voluntarily remove leader key from DCS
+        """Remove leader key from DCS.
         This method should remove leader key if current instance is the leader"""
 
+    def delete_leader(self, last_operation=None):
+        """Update optime/leader and voluntarily remove leader key from DCS.
+        This method should remove leader key if current instance is the leader.
+        :param last_operation: latest checkpoint location in bytes"""
+
+        if last_operation:
+            self.write_leader_optime(last_operation)
+        return self._delete_leader()
+
     @abc.abstractmethod
     def cancel_initialization(self):
         """ Removes the initialize key for a cluster """
@@ -749,8 +794,10 @@ class AbstractDCS(object):
 
     @staticmethod
     def sync_state(leader, sync_standby):
-        """Build sync_state dict"""
+        """Build sync_state dict
-        return {'leader': leader, 'sync_standby': sync_standby}
+           sync_standby dictionary key being kept for backward compatibility
+        """
+        return {'leader': leader, 'sync_standby': sync_standby and ','.join(sorted(sync_standby)) or None}
 
     def write_sync_state(self, leader, sync_standby, index=None):
         sync_value = self.sync_state(leader, sync_standby)

patroni/dcs/consul.py

@@ -9,13 +9,14 @@ import time
 import urllib3
 
 from consul import ConsulException, NotFound, base
-from patroni.dcs import AbstractDCS, ClusterConfig, Cluster, Failover, Leader, Member, SyncState, TimelineHistory
-from patroni.exceptions import DCSError
-from patroni.utils import deep_compare, parse_bool, Retry, RetryFailedError, split_host_port, uri
 from urllib3.exceptions import HTTPError
 from six.moves.urllib.parse import urlencode, urlparse, quote
 from six.moves.http_client import HTTPException
 
+from . import AbstractDCS, Cluster, ClusterConfig, Failover, Leader, Member, SyncState, TimelineHistory
+from ..exceptions import DCSError
+from ..utils import deep_compare, parse_bool, Retry, RetryFailedError, split_host_port, uri, USER_AGENT
+
 logger = logging.getLogger(__name__)
 
 
@@ -52,9 +53,8 @@ class HTTPClient(object):
                 kwargs['cert_file'] = cert
         if ca_cert:
             kwargs['ca_certs'] = ca_cert
-        if verify or ca_cert:
+        kwargs['cert_reqs'] = ssl.CERT_REQUIRED if verify or ca_cert else ssl.CERT_NONE
-            kwargs['cert_reqs'] = ssl.CERT_REQUIRED
+        self.http = urllib3.PoolManager(num_pools=10, maxsize=10, **kwargs)
-        self.http = urllib3.PoolManager(num_pools=10, **kwargs)
         self._ttl = None
 
     def set_read_timeout(self, timeout):
@@ -111,8 +111,9 @@ class HTTPClient(object):
             else:
                 kwargs['timeout'] = self._read_timeout
             token = params.pop('token', self.token) if isinstance(params, dict) else self.token
+            kwargs['headers'] = urllib3.make_headers(user_agent=USER_AGENT)
             if token:
-                kwargs['headers'] = {'X-Consul-Token': token}
+                kwargs['headers']['X-Consul-Token'] = token
             return callback(self.response(self.http.request(method.upper(), self.uri(path, params), **kwargs)))
         return wrapper
 
@@ -215,9 +216,10 @@ class Consul(AbstractDCS):
         self.set_retry_timeout(config['retry_timeout'])
         self.set_ttl(config.get('ttl') or 30)
         self._last_session_refresh = 0
-        self.__session_checks = config.get('checks')
+        self.__session_checks = config.get('checks', [])
         self._register_service = config.get('register_service', False)
         if self._register_service:
+            self._service_tags = config.get('service_tags', [])
             self._service_name = service_name_from_scope_name(self._scope)
             if self._scope != self._service_name:
                 logger.warning('Using %s as consul service name instead of scope name %s', self._service_name,
@@ -366,7 +368,11 @@ class Consul(AbstractDCS):
     def touch_member(self, data, permanent=False):
         cluster = self.cluster
         member = cluster and cluster.get_member(self._name, fallback_to_leader=False)
+
+        try:
             create_member = not permanent and self.refresh_session()
+        except DCSError:
+            return False
 
         if member and (create_member or member.session != self._session):
             self._client.kv.delete(self.member_path)
@@ -409,12 +415,14 @@ class Consul(AbstractDCS):
         conn_parts = urlparse(data['conn_url'])
         check = base.Check.http(api_parts.geturl(), self._service_check_interval,
                                 deregister='{0}s'.format(self._client.http.ttl * 10))
+        tags = self._service_tags[:]
+        tags.append(role)
         params = {
             'service_id': '{0}/{1}'.format(self._scope, self._name),
             'address': conn_parts.hostname,
             'port': conn_parts.port,
             'check': check,
-            'tags': [role]
+            'tags': tags
         }
 
         if state == 'stopped':
@@ -502,7 +510,7 @@ class Consul(AbstractDCS):
         return self._client.kv.put(self.history_path, value)
 
     @catch_consul_errors
-    def delete_leader(self):
+    def _delete_leader(self):
         cluster = self.cluster
         if cluster and isinstance(cluster.leader, Leader) and cluster.leader.name == self._name:
             return self._client.kv.delete(self.leader_path, cas=cluster.leader.index)

patroni/dcs/etcd.py

@@ -1,30 +1,36 @@
 from __future__ import absolute_import
+import abc
 import etcd
 import json
 import logging
 import os
 import urllib3.util.connection
 import random
-import requests
 import six
 import socket
 import time
 
 from dns.exception import DNSException
 from dns import resolver
-from patroni.dcs import AbstractDCS, ClusterConfig, Cluster, Failover, Leader, Member, SyncState, TimelineHistory
+from urllib3 import Timeout
-from patroni.exceptions import DCSError
+from urllib3.exceptions import HTTPError, ReadTimeoutError, ProtocolError
-from patroni.utils import Retry, RetryFailedError, split_host_port, uri
-from urllib3.exceptions import HTTPError, ReadTimeoutError
-from requests.exceptions import RequestException
 from six.moves.queue import Queue
 from six.moves.http_client import HTTPException
 from six.moves.urllib_parse import urlparse
 from threading import Thread
 
+from . import AbstractDCS, Cluster, ClusterConfig, Failover, Leader, Member, SyncState, TimelineHistory
+from ..exceptions import DCSError
+from ..request import get as requests_get
+from ..utils import Retry, RetryFailedError, split_host_port, uri, USER_AGENT
+
 logger = logging.getLogger(__name__)
 
 
+class EtcdRaftInternal(etcd.EtcdException):
+    """Raft Internal Error"""
+
+
 class EtcdError(DCSError):
     pass
 
@@ -65,16 +71,20 @@ class DnsCachingResolver(Thread):
     def resolve_async(self, host, port, attempt=0):
         self._resolve_queue.put(((host, port), attempt))
 
+    def remove(self, host, port):
+        self._cache.pop((host, port), None)
+
     @staticmethod
     def _do_resolve(host, port):
         try:
             return socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM, socket.IPPROTO_TCP)
-        except socket.gaierror:
+        except Exception as e:
-            logger.warning('failed to resolve host %s', host)
+            logger.warning('failed to resolve host %s: %s', host, e)
             return []
 
 
-class Client(etcd.Client):
+@six.add_metaclass(abc.ABCMeta)
+class AbstractEtcdClientWithFailover(etcd.Client):
 
     def __init__(self, config, dns_resolver, cache_ttl=300):
         self._dns_resolver = dns_resolver
@@ -82,34 +92,81 @@ class Client(etcd.Client):
         self._machines_cache_updated = 0
         args = {p: config.get(p) for p in ('host', 'port', 'protocol', 'use_proxies', 'username', 'password',
                                            'cert', 'ca_cert') if config.get(p)}
-        super(Client, self).__init__(read_timeout=config['retry_timeout'], **args)
+        super(AbstractEtcdClientWithFailover, self).__init__(read_timeout=config['retry_timeout'], **args)
         # For some reason python3-etcd on debian and ubuntu are not based on the latest version
         # Workaround for the case when https://github.com/jplana/python-etcd/pull/196 is not applied
         self.http.connection_pool_kw.pop('ssl_version', None)
         self._config = config
+        self._initial_machines_cache = []
         self._load_machines_cache()
         self._allow_reconnect = True
+        # allow passing retry argument to api_execute in params
+        self._comparison_conditions.add('retry')
+        self._read_options.add('retry')
+        self._del_conditions.add('retry')
 
-    def _build_request_parameters(self):
+    def _calculate_timeouts(self, etcd_nodes, timeout=None):
-        kwargs = {'headers': self._get_headers(), 'redirect': self.allow_redirect}
+        """Calculate a request timeout and number of retries per single etcd node.
+        In case if the timeout per node is too small (less than one second) we will reduce the number of nodes.
+        For the cluster with only one node we will try to do 2 retries.
+        For clusters with 2 nodes we will try to do 1 retry for every node.
+        No retries for clusters with 3 or more nodes. We better rely on switching to a different node."""
 
-        # calculate the number of retries and timeout *per node*
+        per_node_timeout = timeout = float(timeout or self.read_timeout)
-        # actual number of retries depends on the number of nodes
-        etcd_nodes = len(self._machines_cache) + 1
-        kwargs['retries'] = 0 if etcd_nodes > 3 else (1 if etcd_nodes > 1 else 2)
 
-        # if etcd_nodes > 3:
+        max_retries = 4 - min(etcd_nodes, 3)
-        #     kwargs.update({'retries': 0, 'timeout': float(self.read_timeout)/etcd_nodes})
+        per_node_retries = 1
-        # elif etcd_nodes > 1:
+        min_timeout = 1.0
-        #     kwargs.update({'retries': 1, 'timeout': self.read_timeout/2.0/etcd_nodes})
+
-        # else:
+        while etcd_nodes > 0:
-        #     kwargs.update({'retries': 2, 'timeout': self.read_timeout/3.0})
+            per_node_timeout = float(timeout) / etcd_nodes
-        kwargs['timeout'] = self.read_timeout/float(kwargs['retries'] + 1)/etcd_nodes
+            if per_node_timeout >= min_timeout:
+                # for small clusters we will try to do more than on try on every node
+                while per_node_retries < max_retries and per_node_timeout / (per_node_retries + 1) >= min_timeout:
+                    per_node_retries += 1
+                per_node_timeout /= per_node_retries
+                break
+            # if the timeout per one node is to small try to reduce number of nodes
+            etcd_nodes -= 1
+            max_retries = 1
+
+        return etcd_nodes, per_node_timeout, per_node_retries - 1
+
+    def reload_config(self, config):
+        self.username = config.get('username')
+        self.password = config.get('password')
+
+    def _get_headers(self):
+        basic_auth = ':'.join((self.username, self.password)) if self.username and self.password else None
+        return urllib3.make_headers(basic_auth=basic_auth, user_agent=USER_AGENT)
+
+    def _prepare_common_parameters(self, etcd_nodes, timeout=None):
+        kwargs = {'headers': self._get_headers(), 'redirect': self.allow_redirect, 'preload_content': False}
+
+        if timeout is not None:
+            kwargs.update(retries=0, timeout=timeout)
+        else:
+            _, per_node_timeout, per_node_retries = self._calculate_timeouts(etcd_nodes)
+            connect_timeout = max(1, per_node_timeout/2)
+            kwargs.update(timeout=Timeout(connect=connect_timeout, total=per_node_timeout), retries=per_node_retries)
         return kwargs
 
     def set_machines_cache_ttl(self, cache_ttl):
         self._machines_cache_ttl = cache_ttl
 
+    @abc.abstractmethod
+    def _prepare_get_members(self, etcd_nodes):
+        """returns: request parameters"""
+
+    @abc.abstractmethod
+    def _get_members(self, base_uri, **kwargs):
+        """returns: list of clientURLs"""
+
+    @property
+    def machines_cache(self):
+        base_uri, cache = self._base_uri, self._machines_cache
+        return ([base_uri] if base_uri in cache else []) + [machine for machine in cache if machine != base_uri]
+
     @property
     def machines(self):
         """Original `machines` method(property) of `etcd.Client` class raise exception
@@ -122,100 +179,101 @@ class Client(etcd.Client):
         Also this method implements the same timeout-retry logic as `api_execute`, because
         the original method was retrying 2 times with the `read_timeout` on each node."""
 
-        kwargs = self._build_request_parameters()
+        machines_cache = self.machines_cache
+        kwargs = self._prepare_get_members(len(machines_cache))
 
-        while True:
+        for base_uri in machines_cache:
             try:
-                response = self.http.request(self._MGET, self._base_uri + self.version_prefix + '/machines', **kwargs)
+                machines = list(self._get_members(base_uri, **kwargs))
-                data = self._handle_server_response(response).data.decode('utf-8')
-                machines = [m.strip() for m in data.split(',') if m.strip()]
                 logger.debug("Retrieved list of machines: %s", machines)
-                if not machines:
+                if machines:
-                    raise etcd.EtcdException
                     random.shuffle(machines)
-                for url in machines:
+                    self._update_dns_cache(self._dns_resolver.resolve_async, machines)
-                    r = urlparse(url)
-                    port = r.port or (443 if r.scheme == 'https' else 80)
-                    self._dns_resolver.resolve_async(r.hostname, port)
                     return machines
             except Exception as e:
-                # We can't get the list of machines, if one server is in the
+                self.http.clear()
-                # machines cache, try on it
+                logger.error("Failed to get list of machines from %s%s: %r", base_uri, self.version_prefix, e)
-                logger.error("Failed to get list of machines from %s%s: %r", self._base_uri, self.version_prefix, e)
+
-                if self._machines_cache:
+        raise etcd.EtcdConnectionFailed('No more machines in the cluster')
-                    self._base_uri = self._machines_cache.pop(0)
-                    logger.info("Retrying on %s", self._base_uri)
-                elif self._update_machines_cache:
-                    raise etcd.EtcdException("Could not get the list of servers, "
-                                             "maybe you provided the wrong "
-                                             "host(s) to connect to?")
-                else:
-                    return []
 
     def set_read_timeout(self, timeout):
         self._read_timeout = timeout
 
-    def _do_http_request(self, request_executor, method, url, fields=None, **kwargs):
+    def _do_http_request(self, retry, machines_cache, request_executor, method, path, fields=None, **kwargs):
+        if fields is not None:
+            kwargs['fields'] = fields
+        some_request_failed = False
+        for i, base_uri in enumerate(machines_cache):
+            if i > 0:
+                logger.info("Retrying on %s", base_uri)
             try:
-            response = request_executor(method, url, fields=fields, **kwargs)
+                response = request_executor(method, base_uri + path, **kwargs)
                 response.data.decode('utf-8')
-            self._check_cluster_id(response)
+                if some_request_failed:
+                    self.set_base_uri(base_uri)
+                    self._refresh_machines_cache()
+                return response
             except (HTTPError, HTTPException, socket.error, socket.timeout) as e:
+                self.http.clear()
+                # switch to the next etcd node because we don't know exactly what happened,
+                # whether the key didn't received an update or there is a network problem.
+                if not retry and i + 1 < len(machines_cache):
+                    self.set_base_uri(machines_cache[i + 1])
                 if (isinstance(fields, dict) and fields.get("wait") == "true" and
-                    isinstance(e, ReadTimeoutError)):
+                        isinstance(e, (ReadTimeoutError, ProtocolError))):
                     logger.debug("Watch timed out.")
                     raise etcd.EtcdWatchTimedOut("Watch timed out: {0}".format(e), cause=e)
-            logger.error("Request to server %s failed: %r", self._base_uri, e)
+                logger.error("Request to server %s failed: %r", base_uri, e)
                 logger.info("Reconnection allowed, looking for another server.")
-            self._base_uri = self._next_server(cause=e)
+                if not retry:
-            response = False
+                    raise etcd.EtcdException('{0} {1} request failed'.format(method, path))
-        return response
+                some_request_failed = True
+
+        raise etcd.EtcdConnectionFailed('No more machines in the cluster')
+
+    @abc.abstractmethod
+    def _prepare_request(self, kwargs, params=None, method=None):
+        """returns: request_executor"""
 
     def api_execute(self, path, method, params=None, timeout=None):
-        if not path.startswith('/'):
+        retry = params.pop('retry', None) if isinstance(params, dict) else None
-            raise ValueError('Path does not start with /')
-
-        kwargs = {'fields': params, 'preload_content': False}
-
-        if method in [self._MGET, self._MDELETE]:
-            request_executor = self.http.request
-        elif method in [self._MPUT, self._MPOST]:
-            request_executor = self.http.request_encode_body
-            kwargs['encode_multipart'] = False
-        else:
-            raise etcd.EtcdException('HTTP method {0} not supported'.format(method))
 
         # Update machines_cache if previous attempt of update has failed
         if self._update_machines_cache:
             self._load_machines_cache()
         elif not self._use_proxies and time.time() - self._machines_cache_updated > self._machines_cache_ttl:
             self._refresh_machines_cache()
-            self._machines_cache_updated = time.time()
 
-        kwargs.update(self._build_request_parameters())
+        machines_cache = self.machines_cache
+        etcd_nodes = len(machines_cache)
 
-        if timeout is not None:
+        kwargs = self._prepare_common_parameters(etcd_nodes, timeout)
-            kwargs.update({'retries': 0, 'timeout': timeout})
+        request_executor = self._prepare_request(kwargs, params, method)
-
-        response = False
 
+        while True:
             try:
-            some_request_failed = False
+                response = self._do_http_request(retry, machines_cache, request_executor, method, path, **kwargs)
-            while not response:
-                response = self._do_http_request(request_executor, method, self._base_uri + path, **kwargs)
-
-                if response is False:
-                    some_request_failed = True
-            if some_request_failed:
-                self._refresh_machines_cache()
-        except etcd.EtcdConnectionFailed as e:
-            if isinstance(e, etcd.EtcdWatchTimedOut) and self._machines_cache:
-                self._base_uri = self._next_server()
-            else:
-                self._update_machines_cache = True
-            if not response:
-                raise
                 return self._handle_server_response(response)
+            except etcd.EtcdWatchTimedOut:
+                raise
+            except etcd.EtcdConnectionFailed as ex:
+                try:
+                    if self._load_machines_cache():
+                        machines_cache = self.machines_cache
+                        etcd_nodes = len(machines_cache)
+                except Exception as e:
+                    logger.debug('Failed to update list of etcd nodes: %r', e)
+                sleeptime = retry.sleeptime
+                remaining_time = retry.stoptime - sleeptime - time.time()
+                nodes, timeout, retries = self._calculate_timeouts(etcd_nodes, remaining_time)
+                if nodes == 0:
+                    self._update_machines_cache = True
+                    raise ex
+                retry.sleep_func(sleeptime)
+                retry.update_delay()
+                # We still have some time left. Partially reduce `machines_cache` and retry request
+                kwargs.update(timeout=Timeout(connect=max(1, timeout/2), total=timeout), retries=retries)
+                machines_cache = machines_cache[:nodes]
 
     @staticmethod
     def get_srv_record(host):
@@ -237,12 +295,12 @@ class Client(etcd.Client):
                 url = uri(protocol, (host, port), endpoint)
                 if endpoint:
                     try:
-                        response = requests.get(url, timeout=self.read_timeout, verify=False)
+                        response = requests_get(url, timeout=self.read_timeout, verify=False)
-                        if response.ok:
+                        if response.status < 400:
-                            for member in response.json():
+                            for member in json.loads(response.data.decode('utf-8')):
                                 ret.extend(member['clientURLs'])
                             break
-                    except RequestException:
+                    except Exception:
                         logger.exception('GET %s', url)
                 else:
                     ret.append(url)
@@ -276,6 +334,13 @@ class Client(etcd.Client):
             machines_cache = self._get_machines_cache_from_dns(self._config['host'], self._config['port'])
         return machines_cache
 
+    @staticmethod
+    def _update_dns_cache(func, machines):
+        for url in machines:
+            r = urlparse(url)
+            port = r.port or (443 if r.scheme == 'https' else 80)
+            func(r.hostname, port)
+
     def _load_machines_cache(self):
         """This method should fill up `_machines_cache` from scratch.
         It could happen only in two cases:
@@ -287,40 +352,95 @@ class Client(etcd.Client):
         if 'srv' not in self._config and 'host' not in self._config and 'hosts' not in self._config:
             raise Exception('Neither srv, hosts, host nor url are defined in etcd section of config')
 
-        self._machines_cache = self._get_machines_cache_from_config()
+        machines_cache = self._get_machines_cache_from_config()
-
         # Can not bootstrap list of etcd-cluster members, giving up
-        if not self._machines_cache:
+        if not machines_cache:
             raise etcd.EtcdException
 
-        # After filling up initial list of machines_cache we should ask etcd-cluster about actual list
+        # enforce resolving dns name,they might get new ips
-        self._base_uri = self._next_server()
+        self._update_dns_cache(self._dns_resolver.remove, machines_cache)
-        self._refresh_machines_cache()
+
+        # The etcd cluster could change its topology over time and depending on how we resolve the initial
+        # topology (list of hosts in the Patroni config or DNS records, A or SRV) we might get into the situation
+        # the the real topology doesn't match anymore with the topology resolved from the configuration file.
+        # In case if the "initial" topology is the same as before we will not override the `_machines_cache`.
+        ret = set(machines_cache) != set(self._initial_machines_cache)
+        if ret:
+            self._initial_machines_cache = self._machines_cache = machines_cache
+
+            # After filling up the initial list of machines_cache we should ask etcd-cluster about actual list
+            self._refresh_machines_cache(True)
 
         self._update_machines_cache = False
+        return ret
+
+    def _refresh_machines_cache(self, updating_cache=False):
+        if self._use_proxies:
+            self._machines_cache = self._get_machines_cache_from_config()
+        else:
+            try:
+                self._machines_cache = self.machines
+            except etcd.EtcdConnectionFailed:
+                if updating_cache:
+                    raise etcd.EtcdException("Could not get the list of servers, "
+                                             "maybe you provided the wrong "
+                                             "host(s) to connect to?")
+                return
+
+        if self._base_uri not in self._machines_cache:
+            self.set_base_uri(self._machines_cache[0])
         self._machines_cache_updated = time.time()
 
-    def _refresh_machines_cache(self):
+    def set_base_uri(self, value):
-        self._machines_cache = self._get_machines_cache_from_config() if self._use_proxies else self.machines
+        logger.info('Selected new etcd server %s', value)
-        if self._base_uri in self._machines_cache:
+        self._base_uri = value
-            self._machines_cache.remove(self._base_uri)
 
 
-class Etcd(AbstractDCS):
+class EtcdClient(AbstractEtcdClientWithFailover):
 
-    def __init__(self, config):
+    ERROR_CLS = EtcdError
-        super(Etcd, self).__init__(config)
+
-        self._ttl = int(config.get('ttl') or 30)
+    def __del__(self):
+        if self.http is not None:
+            try:
+                self.http.clear()
+            except (ReferenceError, TypeError):
+                pass
+
+    def _prepare_get_members(self, etcd_nodes):
+        return self._prepare_common_parameters(etcd_nodes)
+
+    def _get_members(self, base_uri, **kwargs):
+        response = self.http.request(self._MGET, base_uri + self.version_prefix + '/machines', **kwargs)
+        data = self._handle_server_response(response).data.decode('utf-8')
+        return [m.strip() for m in data.split(',') if m.strip()]
+
+    def _prepare_request(self, kwargs, params=None, method=None):
+        kwargs['fields'] = params
+        if method in (self._MPOST, self._MPUT):
+            kwargs['encode_multipart'] = False
+        return self.http.request
+
+
+class AbstractEtcd(AbstractDCS):
+
+    def __init__(self, config, client_cls, retry_errors_cls):
+        super(AbstractEtcd, self).__init__(config)
         self._retry = Retry(deadline=config['retry_timeout'], max_delay=1, max_tries=-1,
-                            retry_exceptions=(etcd.EtcdLeaderElectionInProgress,
+                            retry_exceptions=retry_errors_cls)
-                                              etcd.EtcdWatcherCleared,
+        self._ttl = int(config.get('ttl') or 30)
-                                              etcd.EtcdEventIndexCleared))
+        self._client = self.get_etcd_client(config, client_cls)
-        self._client = self.get_etcd_client(config)
         self.__do_not_watch = False
         self._has_failed = False
 
+    def reload_config(self, config):
+        super(AbstractEtcd, self).reload_config(config)
+        self._client.reload_config(config.get(self.__class__.__name__.lower(), {}))
+
     def retry(self, *args, **kwargs):
-        return self._retry.copy()(*args, **kwargs)
+        retry = self._retry.copy()
+        kwargs['retry'] = retry
+        return retry(*args, **kwargs)
 
     def _handle_exception(self, e, name='', do_sleep=False, raise_ex=None):
         if not self._has_failed:
@@ -333,22 +453,13 @@ class Etcd(AbstractDCS):
         if isinstance(raise_ex, Exception):
             raise raise_ex
 
-    def catch_etcd_errors(func):
-        def wrapper(self, *args, **kwargs):
-            try:
-                retval = func(self, *args, **kwargs) is not None
-                self._has_failed = False
-                return retval
-            except (RetryFailedError, etcd.EtcdException) as e:
-                self._handle_exception(e)
-                return False
-            except Exception as e:
-                self._handle_exception(e, raise_ex=EtcdError('unexpected error'))
-
-        return wrapper
-
     @staticmethod
-    def get_etcd_client(config):
+    def set_socket_options(sock, socket_options):
+        if socket_options:
+            for opt in socket_options:
+                sock.setsockopt(*opt)
+
+    def get_etcd_client(self, config, client_cls):
         if 'proxy' in config:
             config['use_proxies'] = True
             config['url'] = config['proxy']
@@ -368,7 +479,7 @@ class Etcd(AbstractDCS):
             config['hosts'] = []
             for value in hosts:
                 if isinstance(value, six.string_types):
-                    config['hosts'].append(uri(protocol, split_host_port(value, default_port)))
+                    config['hosts'].append(uri(protocol, split_host_port(value.strip(), default_port)))
         elif 'host' in config:
             host, port = split_host_port(config['host'], 2379)
             config['host'] = host
@@ -397,9 +508,7 @@ class Etcd(AbstractDCS):
                 sock = None
                 try:
                     sock = socket.socket(af, socktype, proto)
-                    if socket_options:
+                    self.set_socket_options(sock, socket_options)
-                        for opt in socket_options:
-                            sock.setsockopt(*opt)
                     if timeout is not socket._GLOBAL_DEFAULT_TIMEOUT:
                         sock.settimeout(timeout)
                     if source_address:
@@ -423,7 +532,7 @@ class Etcd(AbstractDCS):
         client = None
         while not client:
             try:
-                client = Client(config, dns_resolver)
+                client = client_cls(config, dns_resolver)
                 if 'use_proxies' in config and not client.machines:
                     raise etcd.EtcdException
             except etcd.EtcdException:
@@ -433,9 +542,10 @@ class Etcd(AbstractDCS):
 
     def set_ttl(self, ttl):
         ttl = int(ttl)
-        self.__do_not_watch = self._ttl != ttl
+        ret = self._ttl != ttl
         self._ttl = ttl
         self._client.set_machines_cache_ttl(ttl*10)
+        return ret
 
     @property
     def ttl(self):
@@ -445,6 +555,31 @@ class Etcd(AbstractDCS):
         self._retry.deadline = retry_timeout
         self._client.set_read_timeout(retry_timeout)
 
+
+def catch_etcd_errors(func):
+    def wrapper(self, *args, **kwargs):
+        try:
+            retval = func(self, *args, **kwargs) is not None
+            self._has_failed = False
+            return retval
+        except (RetryFailedError, etcd.EtcdException) as e:
+            self._handle_exception(e)
+            return False
+        except Exception as e:
+            self._handle_exception(e, raise_ex=self._client.ERROR_CLS('unexpected error'))
+
+    return wrapper
+
+
+class Etcd(AbstractEtcd):
+
+    def __init__(self, config):
+        super(Etcd, self).__init__(config, EtcdClient, (etcd.EtcdLeaderElectionInProgress, EtcdRaftInternal))
+        self.__do_not_watch = False
+
+    def set_ttl(self, ttl):
+        self.__do_not_watch = super(Etcd, self).set_ttl(ttl)
+
     @staticmethod
     def member(node):
         return Member.from_node(node.modifiedIndex, os.path.basename(node.key), node.ttl, node.value)
@@ -506,7 +641,7 @@ class Etcd(AbstractDCS):
 
     @catch_etcd_errors
     def take_leader(self):
-        return self.retry(self._client.set, self.leader_path, self._name, self._ttl)
+        return self.retry(self._client.write, self.leader_path, self._name, ttl=self._ttl)
 
     def attempt_to_acquire_leader(self, permanent=False):
         try:
@@ -535,14 +670,14 @@ class Etcd(AbstractDCS):
 
     @catch_etcd_errors
     def _update_leader(self):
-        return self.retry(self._client.test_and_set, self.leader_path, self._name, self._name, self._ttl)
+        return self.retry(self._client.write, self.leader_path, self._name, prevValue=self._name, ttl=self._ttl)
 
     @catch_etcd_errors
     def initialize(self, create_new=True, sysid=""):
         return self.retry(self._client.write, self.initialize_path, sysid, prevExist=(not create_new))
 
     @catch_etcd_errors
-    def delete_leader(self):
+    def _delete_leader(self):
         return self._client.delete(self.leader_path, prevValue=self._name)
 
     @catch_etcd_errors
@@ -575,13 +710,14 @@ class Etcd(AbstractDCS):
 
             while timeout >= 1:  # when timeout is too small urllib3 doesn't have enough time to connect
                 try:
-                    self._client.watch(self.leader_path, index=leader_index, timeout=timeout + 0.5)
+                    result = self._client.watch(self.leader_path, index=leader_index, timeout=timeout + 0.5)
                     self._has_failed = False
+                    if result.action == 'compareAndSwap':
+                        time.sleep(0.01)
                     # Synchronous work of all cluster members with etcd is less expensive
                     # than reestablishing http connection every time from every replica.
                     return True
                 except etcd.EtcdWatchTimedOut:
-                    self._client.http.clear()
                     self._has_failed = False
                     return False
                 except (etcd.EtcdEventIndexCleared, etcd.EtcdWatcherCleared):  # Watch failed
@@ -596,3 +732,6 @@ class Etcd(AbstractDCS):
             return super(Etcd, self).watch(None, timeout)
         finally:
             self.event.clear()
+
+
+etcd.EtcdError.error_exceptions[300] = EtcdRaftInternal

patroni/dcs/etcd3.py

@@ -0,0 +1,795 @@
+from __future__ import absolute_import
+import base64
+import etcd
+import json
+import logging
+import os
+import six
+import socket
+import sys
+import time
+import urllib3
+
+from threading import Condition, Lock, Thread
+
+from . import ClusterConfig, Cluster, Failover, Leader, Member, SyncState, TimelineHistory
+from .etcd import AbstractEtcdClientWithFailover, AbstractEtcd, catch_etcd_errors
+from ..exceptions import DCSError, PatroniException
+from ..utils import deep_compare, enable_keepalive, iter_response_objects, RetryFailedError, USER_AGENT
+
+logger = logging.getLogger(__name__)
+
+
+class Etcd3Error(DCSError):
+    pass
+
+
+class UnsupportedEtcdVersion(PatroniException):
+    pass
+
+
+# google.golang.org/grpc/codes
+GRPCCode = type('Enum', (), {'OK': 0, 'Canceled': 1, 'Unknown': 2, 'InvalidArgument': 3, 'DeadlineExceeded': 4,
+                             'NotFound': 5, 'AlreadyExists': 6, 'PermissionDenied': 7, 'ResourceExhausted': 8,
+                             'FailedPrecondition': 9, 'Aborted': 10, 'OutOfRange': 11, 'Unimplemented': 12,
+                             'Internal': 13, 'Unavailable': 14, 'DataLoss': 15, 'Unauthenticated': 16})
+GRPCcodeToText = {v: k for k, v in GRPCCode.__dict__.items() if not k.startswith('__') and isinstance(v, int)}
+
+
+class Etcd3Exception(etcd.EtcdException):
+    pass
+
+
+class Etcd3ClientError(Etcd3Exception):
+
+    def __init__(self, code=None, error=None, status=None):
+        if not hasattr(self, 'error'):
+            self.error = error and error.strip()
+        self.codeText = GRPCcodeToText.get(code)
+        self.status = status
+
+    def __repr__(self):
+        return "<{0} error: '{1}', code: {2}>".format(self.__class__.__name__, self.error, self.code)
+
+    __str__ = __repr__
+
+    def as_dict(self):
+        return {'error': self.error, 'code': self.code, 'codeText': self.codeText, 'status': self.status}
+
+    @classmethod
+    def get_subclasses(cls):
+        for subclass in cls.__subclasses__():
+            for subsubclass in subclass.get_subclasses():
+                yield subsubclass
+            yield subclass
+
+
+class Unknown(Etcd3ClientError):
+    code = GRPCCode.Unknown
+
+
+class InvalidArgument(Etcd3ClientError):
+    code = GRPCCode.InvalidArgument
+
+
+class DeadlineExceeded(Etcd3ClientError):
+    code = GRPCCode.DeadlineExceeded
+    error = "context deadline exceeded"
+
+
+class NotFound(Etcd3ClientError):
+    code = GRPCCode.NotFound
+
+
+class FailedPrecondition(Etcd3ClientError):
+    code = GRPCCode.FailedPrecondition
+
+
+class Unavailable(Etcd3ClientError):
+    code = GRPCCode.Unavailable
+
+
+# https://github.com/etcd-io/etcd/blob/master/etcdserver/api/v3rpc/rpctypes/error.go
+class LeaseNotFound(NotFound):
+    error = "etcdserver: requested lease not found"
+
+
+class UserEmpty(InvalidArgument):
+    error = "etcdserver: user name is empty"
+
+
+class PermissionDenied(Etcd3ClientError):
+    code = GRPCCode.PermissionDenied
+    error = "etcdserver: permission denied"
+
+
+class AuthNotEnabled(FailedPrecondition):
+    error = "etcdserver: authentication is not enabled"
+
+
+class InvalidAuthToken(Etcd3ClientError):
+    code = GRPCCode.Unauthenticated
+    error = "etcdserver: invalid auth token"
+
+
+errStringToClientError = {s.error: s for s in Etcd3ClientError.get_subclasses() if hasattr(s, 'error')}
+errCodeToClientError = {s.code: s for s in Etcd3ClientError.__subclasses__()}
+
+
+def _raise_for_data(data, status_code=None):
+    try:
+        error = data.get('error') or data.get('Error')
+        if isinstance(error, dict):  # streaming response
+            status_code = error.get('http_code')
+            code = error['grpc_code']
+            error = error['message']
+        else:
+            code = data.get('code') or data.get('Code')
+    except Exception:
+        error = str(data)
+        code = GRPCCode.Unknown
+    err = errStringToClientError.get(error) or errCodeToClientError.get(code) or Unknown
+    raise err(code, error, status_code)
+
+
+def to_bytes(v):
+    return v if isinstance(v, bytes) else v.encode('utf-8')
+
+
+def prefix_range_end(v):
+    v = bytearray(to_bytes(v))
+    for i in range(len(v) - 1, -1, -1):
+        if v[i] < 0xff:
+            v[i] += 1
+            break
+    return bytes(v)
+
+
+def base64_encode(v):
+    return base64.b64encode(to_bytes(v)).decode('utf-8')
+
+
+def base64_decode(v):
+    return base64.b64decode(v).decode('utf-8')
+
+
+def build_range_request(key, range_end=None):
+    fields = {'key': base64_encode(key)}
+    if range_end:
+        fields['range_end'] = base64_encode(range_end)
+    return fields
+
+
+class Etcd3Client(AbstractEtcdClientWithFailover):
+
+    ERROR_CLS = Etcd3Error
+
+    def __init__(self, config, dns_resolver, cache_ttl=300):
+        self._token = None
+        self._cluster_version = None
+        self.version_prefix = '/v3beta'
+        super(Etcd3Client, self).__init__(config, dns_resolver, cache_ttl)
+
+        if six.PY2:  # pragma: no cover
+            # Old grpc-gateway sometimes sends double 'transfer-encoding: chunked' headers,
+            # what breaks the old (python2.7) httplib.HTTPConnection (it closes the socket).
+            def dedup_addheader(httpm, key, value):
+                prev = httpm.dict.get(key)
+                if prev is None:
+                    httpm.dict[key] = value
+                elif key != 'transfer-encoding' or prev != value:
+                    combined = ", ".join((prev, value))
+                    httpm.dict[key] = combined
+
+            import httplib
+            httplib.HTTPMessage.addheader = dedup_addheader
+
+        try:
+            self.authenticate()
+        except Exception as e:
+            logger.fatal('Etcd3 authentication failed: %r', e)
+            sys.exit(1)
+
+    def _get_headers(self):
+        headers = urllib3.make_headers(user_agent=USER_AGENT)
+        if self._token and self._cluster_version >= (3, 3, 0):
+            headers['authorization'] = self._token
+        return headers
+
+    def _prepare_request(self, kwargs, params=None, method=None):
+        if params is not None:
+            kwargs['body'] = json.dumps(params)
+            kwargs['headers']['Content-Type'] = 'application/json'
+        return self.http.urlopen
+
+    @staticmethod
+    def _handle_server_response(response):
+        data = response.data
+        try:
+            data = data.decode('utf-8')
+            data = json.loads(data)
+        except (TypeError, ValueError, UnicodeError) as e:
+            if response.status < 400:
+                raise etcd.EtcdException('Server response was not valid JSON: %r' % e)
+        if response.status < 400:
+            return data
+        _raise_for_data(data, response.status)
+
+    def _ensure_version_prefix(self, base_uri, **kwargs):
+        if self.version_prefix != '/v3':
+            response = self.http.urlopen(self._MGET, base_uri + '/version', **kwargs)
+            response = self._handle_server_response(response)
+
+            server_version_str = response['etcdserver']
+            server_version = tuple(int(x) for x in server_version_str.split('.'))
+            cluster_version_str = response['etcdcluster']
+            self._cluster_version = tuple(int(x) for x in cluster_version_str.split('.'))
+
+            if self._cluster_version < (3, 0) or server_version < (3, 0, 4):
+                raise UnsupportedEtcdVersion('Detected Etcd version {0} is lower than 3.0.4'.format(server_version_str))
+
+            if self._cluster_version < (3, 3):
+                if self.version_prefix != '/v3alpha':
+                    if self._cluster_version < (3, 1):
+                        logger.warning('Detected Etcd version %s is lower than 3.1.0, watches are not supported',
+                                       cluster_version_str)
+                    if self.username and self.password:
+                        logger.warning('Detected Etcd version %s is lower than 3.3.0, authentication is not supported',
+                                       cluster_version_str)
+                    self.version_prefix = '/v3alpha'
+            elif self._cluster_version < (3, 4):
+                self.version_prefix = '/v3beta'
+            else:
+                self.version_prefix = '/v3'
+
+    def _prepare_get_members(self, etcd_nodes):
+        kwargs = self._prepare_common_parameters(etcd_nodes)
+        self._prepare_request(kwargs, {})
+        return kwargs
+
+    def _get_members(self, base_uri, **kwargs):
+        self._ensure_version_prefix(base_uri, **kwargs)
+        resp = self.http.urlopen(self._MPOST, base_uri + self.version_prefix + '/cluster/member/list', **kwargs)
+        members = self._handle_server_response(resp)['members']
+        return set(url for member in members for url in member.get('clientURLs', []))
+
+    def call_rpc(self, method, fields, retry=None):
+        fields['retry'] = retry
+        return self.api_execute(self.version_prefix + method, self._MPOST, fields)
+
+    def authenticate(self):
+        if self._cluster_version >= (3, 3) and self.username and self.password:
+            logger.info('Trying to authenticate on Etcd...')
+            old_token, self._token = self._token, None
+            try:
+                response = self.call_rpc('/auth/authenticate', {'name': self.username, 'password': self.password})
+            except AuthNotEnabled:
+                logger.info('Etcd authentication is not enabled')
+                self._token = None
+            except Exception:
+                self._token = old_token
+                raise
+            else:
+                self._token = response.get('token')
+            return old_token != self._token
+
+    def _handle_auth_errors(func):
+        def wrapper(self, *args, **kwargs):
+            def retry(ex):
+                if self.username and self.password:
+                    self.authenticate()
+                    return func(self, *args, **kwargs)
+                else:
+                    logger.fatal('Username or password not set, authentication is not possible')
+                    raise ex
+
+            try:
+                return func(self, *args, **kwargs)
+            except (UserEmpty, PermissionDenied) as e:  # no token provided
+                # PermissionDenied is raised on 3.0 and 3.1
+                if self._cluster_version < (3, 3) and (not isinstance(e, PermissionDenied)
+                                                       or self._cluster_version < (3, 2)):
+                    raise UnsupportedEtcdVersion('Authentication is required by Etcd cluster but not '
+                                                 'supported on version lower than 3.3.0. Cluster version: '
+                                                 '{0}'.format('.'.join(map(str, self._cluster_version))))
+                return retry(e)
+            except InvalidAuthToken as e:
+                logger.error('Invalid auth token: %s', self._token)
+                return retry(e)
+
+        return wrapper
+
+    @_handle_auth_errors
+    def range(self, key, range_end=None, retry=None):
+        params = build_range_request(key, range_end)
+        params['serializable'] = True  # For better performance. We can tolerate stale reads.
+        return self.call_rpc('/kv/range', params, retry)
+
+    def prefix(self, key, retry=None):
+        return self.range(key, prefix_range_end(key), retry)
+
+    def lease_grant(self, ttl, retry=None):
+        return self.call_rpc('/lease/grant', {'TTL': ttl}, retry)['ID']
+
+    def lease_keepalive(self, ID, retry=None):
+        return self.call_rpc('/lease/keepalive', {'ID': ID}, retry).get('result', {}).get('TTL')
+
+    def txn(self, compare, success, retry=None):
+        return self.call_rpc('/kv/txn', {'compare': [compare], 'success': [success]}, retry).get('succeeded')
+
+    @_handle_auth_errors
+    def put(self, key, value, lease=None, create_revision=None, mod_revision=None, retry=None):
+        fields = {'key': base64_encode(key), 'value': base64_encode(value)}
+        if lease:
+            fields['lease'] = lease
+        if create_revision is not None:
+            compare = {'target': 'CREATE', 'create_revision': create_revision}
+        elif mod_revision is not None:
+            compare = {'target': 'MOD', 'mod_revision': mod_revision}
+        else:
+            return self.call_rpc('/kv/put', fields, retry)
+        compare['key'] = fields['key']
+        return self.txn(compare, {'request_put': fields}, retry)
+
+    @_handle_auth_errors
+    def deleterange(self, key, range_end=None, mod_revision=None, retry=None):
+        fields = build_range_request(key, range_end)
+        if mod_revision is None:
+            return self.call_rpc('/kv/deleterange', fields, retry)
+        compare = {'target': 'MOD', 'mod_revision': mod_revision, 'key': fields['key']}
+        return self.txn(compare, {'request_delete_range': fields}, retry)
+
+    def deleteprefix(self, key, retry=None):
+        return self.deleterange(key, prefix_range_end(key), retry=retry)
+
+    def watchrange(self, key, range_end=None, start_revision=None, filters=None):
+        """returns: response object"""
+        params = build_range_request(key, range_end)
+        if start_revision is not None:
+            params['start_revision'] = start_revision
+        params['filters'] = filters or []
+        kwargs = self._prepare_common_parameters(1, self.read_timeout)
+        request_executor = self._prepare_request(kwargs, {'create_request': params})
+        kwargs.update(timeout=urllib3.Timeout(connect=kwargs['timeout']), retries=0)
+        return request_executor(self._MPOST, self._base_uri + self.version_prefix + '/watch', **kwargs)
+
+    def watchprefix(self, key, start_revision=None, filters=None):
+        return self.watchrange(key, prefix_range_end(key), start_revision, filters)
+
+
+class KVCache(Thread):
+
+    def __init__(self, dcs, client):
+        Thread.__init__(self)
+        self.daemon = True
+        self._dcs = dcs
+        self._client = client
+        self.condition = Condition()
+        self._config_key = base64_encode(dcs.config_path)
+        self._leader_key = base64_encode(dcs.leader_path)
+        self._optime_key = base64_encode(dcs.leader_optime_path)
+        self._name = base64_encode(dcs._name)
+        self._is_ready = False
+        self._response = None
+        self._response_lock = Lock()
+        self._object_cache = {}
+        self._object_cache_lock = Lock()
+        self.start()
+
+    def set(self, value, overwrite=False):
+        with self._object_cache_lock:
+            name = value['key']
+            old_value = self._object_cache.get(name)
+            ret = not old_value or int(old_value['mod_revision']) < int(value['mod_revision'])
+            if ret or overwrite and old_value['mod_revision'] == value['mod_revision']:
+                self._object_cache[name] = value
+        return ret, old_value
+
+    def delete(self, name, mod_revision):
+        with self._object_cache_lock:
+            old_value = self._object_cache.get(name)
+            ret = old_value and int(old_value['mod_revision']) < int(mod_revision)
+            if ret:
+                del self._object_cache[name]
+        return not old_value or ret, old_value
+
+    def copy(self):
+        with self._object_cache_lock:
+            return [v.copy() for v in self._object_cache.values()]
+
+    def get(self, name):
+        with self._object_cache_lock:
+            return self._object_cache.get(name)
+
+    def _process_event(self, event):
+        kv = event['kv']
+        key = kv['key']
+        if event.get('type') == 'DELETE':
+            success, old_value = self.delete(key, kv['mod_revision'])
+        else:
+            success, old_value = self.set(kv, True)
+
+        if success:
+            old_value = old_value and old_value.get('value')
+            new_value = kv.get('value')
+
+            value_changed = old_value != new_value and \
+                (key == self._leader_key or key == self._optime_key and new_value is not None or
+                 key == self._config_key and old_value is not None and new_value is not None)
+
+            if value_changed:
+                logger.debug('%s changed from %s to %s', key, old_value, new_value)
+
+            # We also want to wake up HA loop on replicas if leader optime was updated
+            if value_changed and (key != self._optime_key or self.get(self._leader_key) != self._name):
+                self._dcs.event.set()
+
+    def _process_message(self, message):
+        logger.debug('Received message: %s', message)
+        if 'error' in message:
+            _raise_for_data(message)
+        for event in message.get('result', {}).get('events', []):
+            self._process_event(event)
+
+    @staticmethod
+    def _finish_response(response):
+        try:
+            response.close()
+        finally:
+            response.release_conn()
+
+    def _do_watch(self, revision):
+        with self._response_lock:
+            self._response = None
+        response = self._client.watchprefix(self._dcs.cluster_prefix, revision)
+        with self._response_lock:
+            if self._response is None:
+                self._response = response
+
+        if not self._response:
+            return self._finish_response(response)
+
+        for message in iter_response_objects(response):
+            self._process_message(message)
+
+    def _build_cache(self):
+        result = self._dcs.retry(self._client.prefix, self._dcs.cluster_prefix)
+        with self._object_cache_lock:
+            self._object_cache = {node['key']: node for node in result.get('kvs', [])}
+        with self.condition:
+            self._is_ready = True
+            self.condition.notify()
+
+        try:
+            self._do_watch(result['header']['revision'])
+        except Exception as e:
+            logger.error('watchprefix failed: %r', e)
+        finally:
+            with self.condition:
+                self._is_ready = False
+            with self._response_lock:
+                response, self._response = self._response, None
+            if response:
+                self._finish_response(response)
+
+    def run(self):
+        while True:
+            try:
+                self._build_cache()
+            except Exception as e:
+                logger.error('KVCache.run %r', e)
+                time.sleep(1)
+
+    def kill_stream(self):
+        sock = None
+        with self._response_lock:
+            if self._response:
+                try:
+                    sock = self._response.connection.sock
+                except Exception:
+                    sock = None
+            else:
+                self._response = False
+        if sock:
+            try:
+                sock.shutdown(socket.SHUT_RDWR)
+                sock.close()
+            except Exception as e:
+                logger.debug('Error on socket.shutdown: %r', e)
+
+    def is_ready(self):
+        """Must be called only when holding the lock on `condition`"""
+        return self._is_ready
+
+
+class PatroniEtcd3Client(Etcd3Client):
+
+    def __init__(self, *args, **kwargs):
+        self._kv_cache = None
+        super(PatroniEtcd3Client, self).__init__(*args, **kwargs)
+
+    def configure(self, etcd3):
+        self._etcd3 = etcd3
+
+    def start_watcher(self):
+        if self._cluster_version >= (3, 1):
+            self._kv_cache = KVCache(self._etcd3, self)
+
+    def _restart_watcher(self):
+        if self._kv_cache:
+            self._kv_cache.kill_stream()
+
+    def set_base_uri(self, value):
+        super(PatroniEtcd3Client, self).set_base_uri(value)
+        self._restart_watcher()
+
+    def authenticate(self):
+        ret = super(PatroniEtcd3Client, self).authenticate()
+        if ret:
+            self._restart_watcher()
+        return ret
+
+    def _wait_cache(self, timeout):
+        stop_time = time.time() + timeout
+        while not self._kv_cache.is_ready():
+            timeout = stop_time - time.time()
+            if timeout <= 0:
+                raise RetryFailedError('Exceeded retry deadline')
+            self._kv_cache.condition.wait(timeout)
+
+    def get_cluster(self):
+        if self._kv_cache:
+            with self._kv_cache.condition:
+                self._wait_cache(self._etcd3._retry.deadline)
+                return self._kv_cache.copy()
+        else:
+            return self._etcd3.retry(self.prefix, self._etcd3.cluster_prefix).get('kvs', [])
+
+    def call_rpc(self, method, fields, retry=None):
+        ret = super(PatroniEtcd3Client, self).call_rpc(method, fields, retry)
+
+        if self._kv_cache:
+            value = delete = None
+            if method == '/kv/txn' and ret.get('succeeded'):
+                on_success = fields['success'][0]
+                value = on_success.get('request_put')
+                delete = on_success.get('request_delete_range')
+            elif method == '/kv/put' and ret:
+                value = fields
+            elif method == '/kv/deleterange' and ret:
+                delete = fields
+
+            if value:
+                value['mod_revision'] = ret['header']['revision']
+                self._kv_cache.set(value)
+            elif delete and 'range_end' not in delete:
+                self._kv_cache.delete(delete['key'], ret['header']['revision'])
+
+        return ret
+
+
+class Etcd3(AbstractEtcd):
+
+    def __init__(self, config):
+        super(Etcd3, self).__init__(config, PatroniEtcd3Client, (DeadlineExceeded, Unavailable, FailedPrecondition))
+        self.__do_not_watch = False
+        self._lease = None
+        self._last_lease_refresh = 0
+
+        self._client.configure(self)
+        if not self._ctl:
+            self._client.start_watcher()
+            self.create_lease()
+
+    def set_socket_options(self, sock, socket_options):
+        enable_keepalive(sock, self.ttl, int(self.loop_wait + self._retry.deadline))
+
+    def set_ttl(self, ttl):
+        self.__do_not_watch = super(Etcd3, self).set_ttl(ttl)
+        if self.__do_not_watch:
+            self._lease = None
+
+    def _do_refresh_lease(self, retry=None):
+        if self._lease and self._last_lease_refresh + self._loop_wait > time.time():
+            return False
+
+        if self._lease and not self._client.lease_keepalive(self._lease, retry):
+            self._lease = None
+
+        ret = not self._lease
+        if ret:
+            self._lease = self._client.lease_grant(self._ttl, retry)
+
+        self._last_lease_refresh = time.time()
+        return ret
+
+    def refresh_lease(self):
+        try:
+            return self.retry(self._do_refresh_lease)
+        except (Etcd3ClientError, RetryFailedError):
+            logger.exception('refresh_lease')
+        raise Etcd3Error('Failed ro keepalive/grant lease')
+
+    def create_lease(self):
+        while not self._lease:
+            try:
+                self.refresh_lease()
+            except Etcd3Error:
+                logger.info('waiting on etcd')
+                time.sleep(5)
+
+    @property
+    def cluster_prefix(self):
+        return self.client_path('')
+
+    @staticmethod
+    def member(node):
+        return Member.from_node(node['mod_revision'], os.path.basename(node['key']), node['lease'], node['value'])
+
+    def _load_cluster(self):
+        cluster = None
+        try:
+            path_len = len(self.cluster_prefix)
+
+            nodes = {}
+            for node in self._client.get_cluster():
+                node['key'] = base64_decode(node['key'])
+                node['value'] = base64_decode(node.get('value', ''))
+                node['lease'] = node.get('lease')
+                nodes[node['key'][path_len:].lstrip('/')] = node
+
+            # get initialize flag
+            initialize = nodes.get(self._INITIALIZE)
+            initialize = initialize and initialize['value']
+
+            # get global dynamic configuration
+            config = nodes.get(self._CONFIG)
+            config = config and ClusterConfig.from_node(config['mod_revision'], config['value'])
+
+            # get timeline history
+            history = nodes.get(self._HISTORY)
+            history = history and TimelineHistory.from_node(history['mod_revision'], history['value'])
+
+            # get last leader operation
+            last_leader_operation = nodes.get(self._LEADER_OPTIME)
+            last_leader_operation = 0 if last_leader_operation is None else int(last_leader_operation['value'])
+
+            # get list of members
+            members = [self.member(n) for k, n in nodes.items() if k.startswith(self._MEMBERS) and k.count('/') == 1]
+
+            # get leader
+            leader = nodes.get(self._LEADER)
+            if not self._ctl and leader and leader['value'] == self._name and self._lease != leader.get('lease'):
+                logger.warning('I am the leader but not owner of the lease')
+
+            if leader:
+                member = Member(-1, leader['value'], None, {})
+                member = ([m for m in members if m.name == leader['value']] or [member])[0]
+                leader = Leader(leader['mod_revision'], leader['lease'], member)
+
+            # failover key
+            failover = nodes.get(self._FAILOVER)
+            if failover:
+                failover = Failover.from_node(failover['mod_revision'], failover['value'])
+
+            # get synchronization state
+            sync = nodes.get(self._SYNC)
+            sync = SyncState.from_node(sync and sync['mod_revision'], sync and sync['value'])
+
+            cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+        except UnsupportedEtcdVersion:
+            raise
+        except Exception as e:
+            self._handle_exception(e, 'get_cluster', raise_ex=Etcd3Error('Etcd is not responding properly'))
+        self._has_failed = False
+        return cluster
+
+    @catch_etcd_errors
+    def touch_member(self, data, permanent=False):
+        if not permanent:
+            try:
+                self.refresh_lease()
+            except Etcd3Error:
+                return False
+
+        cluster = self.cluster
+        member = cluster and cluster.get_member(self._name, fallback_to_leader=False)
+
+        if member and member.session == self._lease and deep_compare(data, member.data):
+            return True
+
+        data = json.dumps(data, separators=(',', ':'))
+        try:
+            return self._client.put(self.member_path, data, None if permanent else self._lease)
+        except LeaseNotFound:
+            self._lease = None
+            logger.error('Our lease disappeared from Etcd, can not "touch_member"')
+
+    @catch_etcd_errors
+    def take_leader(self):
+        return self.retry(self._client.put, self.leader_path, self._name, self._lease)
+
+    @catch_etcd_errors
+    def _do_attempt_to_acquire_leader(self, permanent):
+        try:
+            return self.retry(self._client.put, self.leader_path, self._name, None if permanent else self._lease, 0)
+        except LeaseNotFound:
+            self._lease = None
+            logger.error('Our lease disappeared from Etcd. Will try to get a new one and retry attempt')
+            self.refresh_lease()
+            return self.retry(self._client.put, self.leader_path, self._name, None if permanent else self._lease, 0)
+
+    def attempt_to_acquire_leader(self, permanent=False):
+        if not self._lease and not permanent:
+            self.refresh_lease()
+
+        ret = self._do_attempt_to_acquire_leader(permanent)
+        if not ret:
+            logger.info('Could not take out TTL lock')
+        return ret
+
+    @catch_etcd_errors
+    def set_failover_value(self, value, index=None):
+        return self._client.put(self.failover_path, value, mod_revision=index)
+
+    @catch_etcd_errors
+    def set_config_value(self, value, index=None):
+        return self._client.put(self.config_path, value, mod_revision=index)
+
+    @catch_etcd_errors
+    def _write_leader_optime(self, last_operation):
+        return self._client.put(self.leader_optime_path, last_operation)
+
+    @catch_etcd_errors
+    def _update_leader(self):
+        if not self._lease:
+            self.refresh_lease()
+        elif self.retry(self._client.lease_keepalive, self._lease):
+            self._last_lease_refresh = time.time()
+
+        if self._lease:
+            cluster = self.cluster
+            leader_lease = cluster and isinstance(cluster.leader, Leader) and cluster.leader.session
+            if leader_lease != self._lease:
+                self.take_leader()
+        return bool(self._lease)
+
+    @catch_etcd_errors
+    def initialize(self, create_new=True, sysid=""):
+        return self.retry(self._client.put, self.initialize_path, sysid, None, 0 if create_new else None)
+
+    @catch_etcd_errors
+    def _delete_leader(self):
+        cluster = self.cluster
+        if cluster and isinstance(cluster.leader, Leader) and cluster.leader.name == self._name:
+            return self._client.deleterange(self.leader_path, mod_revision=cluster.leader.index)
+
+    @catch_etcd_errors
+    def cancel_initialization(self):
+        return self.retry(self._client.deleterange, self.initialize_path)
+
+    @catch_etcd_errors
+    def delete_cluster(self):
+        return self.retry(self._client.deleteprefix, self.cluster_prefix)
+
+    @catch_etcd_errors
+    def set_history_value(self, value):
+        return self._client.put(self.history_path, value)
+
+    @catch_etcd_errors
+    def set_sync_state_value(self, value, index=None):
+        return self.retry(self._client.put, self.sync_path, value, mod_revision=index)
+
+    @catch_etcd_errors
+    def delete_sync_state(self, index=None):
+        return self.retry(self._client.deleterange, self.sync_path, mod_revision=index)
+
+    def watch(self, leader_index, timeout):
+        if self.__do_not_watch:
+            self.__do_not_watch = False
+            return True
+
+        try:
+            return super(Etcd3, self).watch(None, timeout)
+        finally:
+            self.event.clear()

patroni/dcs/exhibitor.py

@@ -1,11 +1,11 @@
+import json
 import logging
 import random
-import requests
 import time
 
 from patroni.dcs.zookeeper import ZooKeeper
+from patroni.request import get as requests_get
 from patroni.utils import uri
-from requests.exceptions import RequestException
 
 logger = logging.getLogger(__name__)
 
@@ -48,10 +48,10 @@ class ExhibitorEnsembleProvider(object):
         random.shuffle(exhibitors)
         for host in exhibitors:
             try:
-                response = requests.get(uri('http', (host, self._exhibitor_port), self._uri_path), timeout=self.TIMEOUT)
+                response = requests_get(uri('http', (host, self._exhibitor_port), self._uri_path), timeout=self.TIMEOUT)
-                return response.json()
+                return json.loads(response.data.decode('utf-8'))
-            except RequestException:
+            except Exception:
-                pass
+                logging.debug('Request to %s failed', host)
         return None
 
     @property

patroni/dcs/raft.py

@@ -0,0 +1,409 @@
+import json
+import logging
+import os
+import threading
+import time
+
+from patroni.dcs import AbstractDCS, ClusterConfig, Cluster, Failover, Leader, Member, SyncState, TimelineHistory
+from pysyncobj import SyncObj, SyncObjConf, replicated, FAIL_REASON
+from pysyncobj.transport import Node, TCPTransport, CONNECTION_STATE
+
+logger = logging.getLogger(__name__)
+
+
+class MessageNode(Node):
+
+    def __init__(self, address):
+        self.address = address
+
+
+class UtilityTransport(TCPTransport):
+
+    def __init__(self, syncObj, selfNode, otherNodes):
+        super(UtilityTransport, self).__init__(syncObj, selfNode, otherNodes)
+        self._selfIsReadonlyNode = False
+
+    def _connectIfNecessarySingle(self, node):
+        pass
+
+    def connectionState(self, node):
+        return self._connections[node].state
+
+    def isDisconnected(self, node):
+        return self.connectionState(node) == CONNECTION_STATE.DISCONNECTED
+
+    def connectIfRequiredSingle(self, node):
+        if self.isDisconnected(node):
+            return self._connections[node].connect(node.ip, node.port)
+
+    def disconnectSingle(self, node):
+        self._connections[node].disconnect()
+
+
+class SyncObjUtility(SyncObj):
+
+    def __init__(self, otherNodes, conf):
+        autoTick = conf.autoTick
+        conf.autoTick = False
+        super(SyncObjUtility, self).__init__(None, otherNodes, conf, transportClass=UtilityTransport)
+        conf.autoTick = autoTick
+        self._SyncObj__transport.setOnMessageReceivedCallback(self._onMessageReceived)
+        self.__result = None
+
+    def setPartnerNode(self, partner):
+        self.__node = partner
+
+    def sendMessage(self, message):
+        # Abuse the fact that node address is send as a first message
+        self._SyncObj__transport._selfNode = MessageNode(message)
+        self._SyncObj__transport.connectIfRequiredSingle(self.__node)
+        while not self._SyncObj__transport.isDisconnected(self.__node):
+            self._poller.poll(0.5)
+        return self.__result
+
+    def _onMessageReceived(self, _, message):
+        self.__result = message
+        self._SyncObj__transport.disconnectSingle(self.__node)
+
+
+class MyTCPTransport(TCPTransport):
+
+    def _onIncomingMessageReceived(self, conn, message):
+        if self._syncObj.encryptor and not conn.sendRandKey:
+            conn.sendRandKey = message
+            conn.recvRandKey = os.urandom(32)
+            conn.send(conn.recvRandKey)
+            return
+
+        # Utility messages
+        if isinstance(message, list) and message[0] == 'members':
+            conn.send(self._syncObj._get_members())
+            return True
+
+        return super(MyTCPTransport, self)._onIncomingMessageReceived(conn, message)
+
+
+class DynMemberSyncObj(SyncObj):
+
+    def __init__(self, selfAddress, partnerAddrs, conf):
+        add_self = False
+        if selfAddress:
+            utility = SyncObjUtility(partnerAddrs, conf)
+            for node in utility._SyncObj__otherNodes:
+                utility.setPartnerNode(node)
+                response = utility.sendMessage(['members'])
+                if response:
+                    partnerAddrs = [member['addr'] for member in response if member['addr'] != selfAddress]
+                    add_self = len(partnerAddrs) == len(response)
+                    break
+
+        super(DynMemberSyncObj, self).__init__(selfAddress, partnerAddrs, conf, transportClass=MyTCPTransport)
+        if add_self:
+            threading.Thread(target=utility.sendMessage, args=(['add', selfAddress],)).start()
+
+    def _get_members(self):
+        ret = [{'addr': node.id, 'leader': node == self._getLeader(),
+                'status': CONNECTION_STATE.CONNECTED if node in self._SyncObj__connectedNodes
+                else CONNECTION_STATE.DISCONNECTED} for node in self._SyncObj__otherNodes]
+        ret.append({'addr': self._SyncObj__selfNode.id, 'leader': self._isLeader(),
+                    'status': CONNECTION_STATE.CONNECTED})
+        return ret
+
+    def _SyncObj__doChangeCluster(self, request, reverse=False):
+        ret = False
+        if not self._SyncObj__selfNode or request[0] != 'add' or reverse or request[1] != self._SyncObj__selfNode.id:
+            ret = super(DynMemberSyncObj, self)._SyncObj__doChangeCluster(request, reverse)
+            if ret:
+                self.forceLogCompaction()
+        return ret
+
+
+class KVStoreTTL(DynMemberSyncObj):
+
+    def __init__(self, selfAddress, partnerAddrs, conf, on_set=None, on_delete=None):
+        self.__on_set = on_set
+        self.__on_delete = on_delete
+        self.__limb = {}
+        self.__retry_timeout = None
+        self.__early_apply_local_log = selfAddress is not None
+        self.applied_local_log = False
+        super(KVStoreTTL, self).__init__(selfAddress, partnerAddrs, conf)
+        self.__data = {}
+
+    @staticmethod
+    def __check_requirements(old_value, **kwargs):
+        return ('prevExist' not in kwargs or bool(kwargs['prevExist']) == bool(old_value)) and \
+            ('prevValue' not in kwargs or old_value and old_value['value'] == kwargs['prevValue']) and \
+            (not kwargs.get('prevIndex') or old_value and old_value['index'] == kwargs['prevIndex'])
+
+    def set_retry_timeout(self, retry_timeout):
+        self.__retry_timeout = retry_timeout
+
+    def retry(self, func, *args, **kwargs):
+        event = threading.Event()
+        ret = {'result': None, 'error': -1}
+
+        def callback(result, error):
+            ret.update(result=result, error=error)
+            event.set()
+
+        kwargs['callback'] = callback
+        timeout = kwargs.pop('timeout', None) or self.__retry_timeout
+        deadline = timeout and time.time() + timeout
+
+        while True:
+            event.clear()
+            func(*args, **kwargs)
+            event.wait(timeout)
+            if ret['error'] == FAIL_REASON.SUCCESS:
+                return ret['result']
+            elif ret['error'] == FAIL_REASON.REQUEST_DENIED:
+                break
+            elif deadline:
+                timeout = deadline - time.time()
+                if timeout <= 0:
+                    break
+            time.sleep(1)
+        return False
+
+    @replicated
+    def _set(self, key, value, **kwargs):
+        old_value = self.__data.get(key, {})
+        if not self.__check_requirements(old_value, **kwargs):
+            return False
+
+        if old_value and old_value['created'] != value['created']:
+            value['created'] = value['updated']
+        value['index'] = self._SyncObj__raftLastApplied + 1
+
+        self.__data[key] = value
+        if self.__on_set:
+            self.__on_set(key, value)
+        return True
+
+    def set(self, key, value, ttl=None, **kwargs):
+        old_value = self.__data.get(key, {})
+        if not self.__check_requirements(old_value, **kwargs):
+            return False
+
+        value = {'value': value, 'updated': time.time()}
+        value['created'] = old_value.get('created', value['updated'])
+        if ttl:
+            value['expire'] = value['updated'] + ttl
+        return self.retry(self._set, key, value, **kwargs)
+
+    def __pop(self, key):
+        self.__data.pop(key)
+        if self.__on_delete:
+            self.__on_delete(key)
+
+    @replicated
+    def _delete(self, key, recursive=False, **kwargs):
+        if recursive:
+            for k in list(self.__data.keys()):
+                if k.startswith(key):
+                    self.__pop(k)
+        elif not self.__check_requirements(self.__data.get(key, {}), **kwargs):
+            return False
+        else:
+            self.__pop(key)
+        return True
+
+    def delete(self, key, recursive=False, **kwargs):
+        if not recursive and not self.__check_requirements(self.__data.get(key, {}), **kwargs):
+            return False
+        return self.retry(self._delete, key, recursive=recursive, **kwargs)
+
+    @staticmethod
+    def __values_match(old, new):
+        return all(old.get(n) == new.get(n) for n in ('created', 'updated', 'expire', 'value'))
+
+    @replicated
+    def _expire(self, key, value, callback=None):
+        current = self.__data.get(key)
+        if current and self.__values_match(current, value):
+            self.__pop(key)
+
+    def __expire_keys(self):
+        for key, value in self.__data.items():
+            if value and 'expire' in value and value['expire'] <= time.time() and \
+                    not (key in self.__limb and self.__values_match(self.__limb[key], value)):
+                self.__limb[key] = value
+
+                def callback(*args):
+                    if key in self.__limb and self.__values_match(self.__limb[key], value):
+                        self.__limb.pop(key)
+                self._expire(key, value, callback=callback)
+
+    def get(self, key, recursive=False):
+        if not recursive:
+            return self.__data.get(key)
+        return {k: v for k, v in self.__data.items() if k.startswith(key)}
+
+    def _onTick(self, timeToWait=0.0):
+        # The SyncObj starts applying the local log only when there is at least one node connected.
+        # We want to change this behavior and apply the local log even when there is nobody except us.
+        # It gives us at least some picture about the last known cluster state.
+        if self.__early_apply_local_log and not self.applied_local_log and self._SyncObj__needLoadDumpFile:
+            self._SyncObj__raftCommitIndex = self._SyncObj__getCurrentLogIndex()
+            self._SyncObj__raftCurrentTerm = self._SyncObj__getCurrentLogTerm()
+
+        super(KVStoreTTL, self)._onTick(timeToWait)
+
+        # The SyncObj calls onReady callback only when cluster got the leader and is ready for writes.
+        # In some cases for us it is safe to "signal" the Raft object when the local log is fully applied.
+        # We are using the `applied_local_log` property for that, but not calling the callback function.
+        if self.__early_apply_local_log and not self.applied_local_log and self._SyncObj__raftCommitIndex != 1 and \
+                self._SyncObj__raftLastApplied == self._SyncObj__raftCommitIndex:
+            self.applied_local_log = True
+
+        if self._isLeader():
+            self.__expire_keys()
+        else:
+            self.__limb.clear()
+
+
+class Raft(AbstractDCS):
+
+    def __init__(self, config):
+        super(Raft, self).__init__(config)
+        self._ttl = int(config.get('ttl') or 30)
+
+        self_addr = None if self._ctl else config.get('self_addr')
+        template = os.path.join(config.get('data_dir', ''), self_addr or '')
+        files = {'journalFile': template + '.journal', 'fullDumpFile': template + '.dump'} if self_addr else {}
+
+        ready_event = threading.Event()
+        conf = SyncObjConf(commandsWaitLeader=False, appendEntriesUseBatch=False, onReady=ready_event.set,
+                           dynamicMembershipChange=True, **files)
+        self._sync_obj = KVStoreTTL(self_addr, config.get('partner_addrs', []), conf, self._on_set, self._on_delete)
+        while True:
+            ready_event.wait(5)
+            if ready_event.isSet() or self._sync_obj.applied_local_log:
+                break
+            else:
+                logger.info('waiting on raft')
+        self._sync_obj.forceLogCompaction()
+        self.set_retry_timeout(int(config.get('retry_timeout') or 10))
+
+    def _on_set(self, key, value):
+        leader = (self._sync_obj.get(self.leader_path) or {}).get('value')
+        if key == value['created'] == value['updated'] and \
+                (key.startswith(self.members_path) or key == self.leader_path and leader != self._name) or \
+                key == self.leader_optime_path and leader != self._name or key in (self.config_path, self.sync_path):
+            self.event.set()
+
+    def _on_delete(self, key):
+        if key == self.leader_path:
+            self.event.set()
+
+    def set_ttl(self, ttl):
+        self._ttl = ttl
+
+    @property
+    def ttl(self):
+        return self._ttl
+
+    def set_retry_timeout(self, retry_timeout):
+        self._sync_obj.set_retry_timeout(retry_timeout)
+
+    @staticmethod
+    def member(key, value):
+        return Member.from_node(value['index'], os.path.basename(key), None, value['value'])
+
+    def _load_cluster(self):
+        prefix = self.client_path('')
+        response = self._sync_obj.get(prefix, recursive=True)
+        if not response:
+            return Cluster(None, None, None, None, [], None, None, None)
+        nodes = {os.path.relpath(key, prefix).replace('\\', '/'): value for key, value in response.items()}
+
+        # get initialize flag
+        initialize = nodes.get(self._INITIALIZE)
+        initialize = initialize and initialize['value']
+
+        # get global dynamic configuration
+        config = nodes.get(self._CONFIG)
+        config = config and ClusterConfig.from_node(config['index'], config['value'])
+
+        # get timeline history
+        history = nodes.get(self._HISTORY)
+        history = history and TimelineHistory.from_node(history['index'], history['value'])
+
+        # get last leader operation
+        last_leader_operation = nodes.get(self._LEADER_OPTIME)
+        last_leader_operation = 0 if last_leader_operation is None else int(last_leader_operation['value'])
+
+        # get list of members
+        members = [self.member(k, n) for k, n in nodes.items() if k.startswith(self._MEMBERS) and k.count('/') == 1]
+
+        # get leader
+        leader = nodes.get(self._LEADER)
+        if leader:
+            member = Member(-1, leader['value'], None, {})
+            member = ([m for m in members if m.name == leader['value']] or [member])[0]
+            leader = Leader(leader['index'], None, member)
+
+        # failover key
+        failover = nodes.get(self._FAILOVER)
+        if failover:
+            failover = Failover.from_node(failover['index'], failover['value'])
+
+        # get synchronization state
+        sync = nodes.get(self._SYNC)
+        sync = SyncState.from_node(sync and sync['index'], sync and sync['value'])
+
+        return Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+
+    def _write_leader_optime(self, last_operation):
+        return self._sync_obj.set(self.leader_optime_path, last_operation, timeout=1)
+
+    def _update_leader(self):
+        ret = self._sync_obj.set(self.leader_path, self._name, ttl=self._ttl, prevValue=self._name)
+        if not ret and self._sync_obj.get(self.leader_path) is None:
+            ret = self.attempt_to_acquire_leader()
+        return ret
+
+    def attempt_to_acquire_leader(self, permanent=False):
+        return self._sync_obj.set(self.leader_path, self._name, prevExist=False,
+                                  ttl=None if permanent else self._ttl)
+
+    def set_failover_value(self, value, index=None):
+        return self._sync_obj.set(self.failover_path, value, prevIndex=index)
+
+    def set_config_value(self, value, index=None):
+        return self._sync_obj.set(self.config_path, value, prevIndex=index)
+
+    def touch_member(self, data, permanent=False):
+        data = json.dumps(data, separators=(',', ':'))
+        return self._sync_obj.set(self.member_path, data, None if permanent else self._ttl, timeout=2)
+
+    def take_leader(self):
+        return self._sync_obj.set(self.leader_path, self._name, ttl=self._ttl)
+
+    def initialize(self, create_new=True, sysid=''):
+        return self._sync_obj.set(self.initialize_path, sysid, prevExist=(not create_new))
+
+    def _delete_leader(self):
+        return self._sync_obj.delete(self.leader_path, prevValue=self._name, timeout=1)
+
+    def cancel_initialization(self):
+        return self._sync_obj.delete(self.initialize_path)
+
+    def delete_cluster(self):
+        return self._sync_obj.delete(self.client_path(''), recursive=True)
+
+    def set_history_value(self, value):
+        return self._sync_obj.set(self.history_path, value)
+
+    def set_sync_state_value(self, value, index=None):
+        return self._sync_obj.set(self.sync_path, value, prevIndex=index)
+
+    def delete_sync_state(self, index=None):
+        return self._sync_obj.delete(self.sync_path, prevIndex=index)
+
+    def watch(self, leader_index, timeout):
+        try:
+            return super(Raft, self).watch(leader_index, timeout)
+        finally:
+            self.event.clear()

patroni/dcs/zookeeper.py

@@ -63,20 +63,25 @@ class ZooKeeper(AbstractDCS):
         if isinstance(hosts, list):
             hosts = ','.join(hosts)
 
+        mapping = {'use_ssl': 'use_ssl', 'verify': 'verify_certs', 'cacert': 'ca',
+                   'cert': 'certfile', 'key': 'keyfile', 'key_password': 'keyfile_password'}
+        kwargs = {v: config[k] for k, v in mapping.items() if k in config}
+
         self._client = KazooClient(hosts, handler=PatroniSequentialThreadingHandler(config['retry_timeout']),
                                    timeout=config['ttl'], connection_retry=KazooRetry(max_delay=1, max_tries=-1,
                                    sleep_func=time.sleep), command_retry=KazooRetry(deadline=config['retry_timeout'],
-                                   max_delay=1, max_tries=-1, sleep_func=time.sleep))
+                                   max_delay=1, max_tries=-1, sleep_func=time.sleep), **kwargs)
         self._client.add_listener(self.session_listener)
 
         self._fetch_cluster = True
+        self._fetch_optime = True
 
         self._orig_kazoo_connect = self._client._connection._connect
         self._client._connection._connect = self._kazoo_connect
 
         self._client.start()
 
-    def _kazoo_connect(self, host, port):
+    def _kazoo_connect(self, *args):
         """Kazoo is using Ping's to determine health of connection to zookeeper. If there is no
         response on Ping after Ping interval (1/2 from read_timeout) it will consider current
         connection dead and try to connect to another node. Without this "magic" it was taking
@@ -88,16 +93,20 @@ class ZooKeeper(AbstractDCS):
         than loop_wait, because we can spend up to 2 seconds when calling `touch_member()` and
         `write_leader_optime()` methods, which also may hang..."""
 
-        ret = self._orig_kazoo_connect(host, port)
+        ret = self._orig_kazoo_connect(*args)
         return max(self.loop_wait - 2, 2)*1000, ret[1]
 
     def session_listener(self, state):
         if state in [KazooState.SUSPENDED, KazooState.LOST]:
             self.cluster_watcher(None)
 
+    def optime_watcher(self, event):
+        self._fetch_optime = True
+        self.event.set()
+
     def cluster_watcher(self, event):
         self._fetch_cluster = True
-        self.event.set()
+        self.optime_watcher(event)
 
     def reload_config(self, config):
         self.set_retry_timeout(config['retry_timeout'])
@@ -141,6 +150,12 @@ class ZooKeeper(AbstractDCS):
         except NoNodeError:
             return None
 
+    def get_leader_optime(self, leader):
+        watch = self.optime_watcher if not leader or leader.name != self._name else None
+        optime = self.get_node(self.leader_optime_path, watch)
+        self._fetch_optime = False
+        return optime and int(optime[0]) or 0
+
     @staticmethod
     def member(name, value, znode):
         return Member.from_node(znode.version, name, znode.ephemeralOwner, value)
@@ -154,7 +169,7 @@ class ZooKeeper(AbstractDCS):
     def load_members(self, sync_standby):
         members = []
         for member in self.get_children(self.members_path, self.cluster_watcher):
-            watch = member == sync_standby and self.cluster_watcher or None
+            watch = member in sync_standby and self.cluster_watcher or None
             data = self.get_node(self.members_path + member, watch)
             if data is not None:
                 members.append(self.member(member, *data))
@@ -178,16 +193,12 @@ class ZooKeeper(AbstractDCS):
         history = self.get_node(self.history_path, watch=self.cluster_watcher) if self._HISTORY in nodes else None
         history = history and TimelineHistory.from_node(history[1].mzxid, history[0])
 
-        # get last leader operation
-        last_leader_operation = self._OPTIME in nodes and self._fetch_cluster and self.get_node(self.leader_optime_path)
-        last_leader_operation = last_leader_operation and int(last_leader_operation[0]) or 0
-
         # get synchronization state
         sync = self.get_node(self.sync_path, watch=self.cluster_watcher) if self._SYNC in nodes else None
         sync = SyncState.from_node(sync and sync[1].version, sync and sync[0])
 
         # get list of members
-        sync_standby = sync.leader == self._name and sync.sync_standby or None
+        sync_standby = sync.leader == self._name and sync.members or []
         members = self.load_members(sync_standby) if self._MEMBERS[:-1] in nodes else []
 
         # get leader
@@ -206,6 +217,9 @@ class ZooKeeper(AbstractDCS):
                 leader = Leader(leader[1].version, leader[1].ephemeralOwner, member)
                 self._fetch_cluster = member.index == -1
 
+        # get last leader operation
+        last_leader_operation = self._OPTIME in nodes and self.get_leader_optime(leader)
+
         # failover key
         failover = self.get_node(self.failover_path, watch=self.cluster_watcher) if self._FAILOVER in nodes else None
         failover = failover and Failover.from_node(failover[1].version, failover[0])
@@ -221,8 +235,20 @@ class ZooKeeper(AbstractDCS):
                 logger.exception('get_cluster')
                 self.cluster_watcher(None)
                 raise ZooKeeperError('ZooKeeper in not responding properly')
+        # Optime ZNode was updated or doesn't exist and we are not leader
+        elif (self._fetch_optime and not self._fetch_cluster or not cluster.last_leader_operation) and\
+                not (cluster.leader and cluster.leader.name == self._name):
+            try:
+                optime = self.get_leader_optime(cluster.leader)
+                cluster = Cluster(cluster.initialize, cluster.config, cluster.leader, optime,
+                                  cluster.members, cluster.failover, cluster.sync, cluster.history)
+            except Exception:
+                pass
         return cluster
 
+    def _bypass_caches(self):
+        self._fetch_cluster = True
+
     def _create(self, path, value, retry=False, ephemeral=False):
         try:
             if retry:
@@ -315,7 +341,7 @@ class ZooKeeper(AbstractDCS):
     def _update_leader(self):
         return True
 
-    def delete_leader(self):
+    def _delete_leader(self):
         self._client.restart()
         return True
 
@@ -346,6 +372,6 @@ class ZooKeeper(AbstractDCS):
         return self.set_sync_state_value("{}", index)
 
     def watch(self, leader_index, timeout):
-        if super(ZooKeeper, self).watch(leader_index, timeout):
+        if super(ZooKeeper, self).watch(leader_index, timeout) and not self._fetch_optime:
             self._fetch_cluster = True
         return self._fetch_cluster

patroni/exceptions.py

@@ -13,6 +13,10 @@ class PatroniException(Exception):
         return repr(self.value)
 
 
+class PatroniFatalException(PatroniException):
+    pass
+
+
 class PostgresException(PatroniException):
     pass
 
@@ -27,3 +31,7 @@ class PostgresConnectionException(PostgresException):
 
 class WatchdogError(PatroniException):
     pass
+
+
+class ConfigParseError(PatroniException):
+    pass

patroni/ha.py

@@ -3,7 +3,6 @@ import functools
 import json
 import logging
 import psycopg2
-import requests
 import sys
 import time
 import uuid
@@ -11,11 +10,11 @@ import uuid
 from collections import namedtuple
 from multiprocessing.pool import ThreadPool
 from patroni.async_executor import AsyncExecutor, CriticalTask
-from patroni.exceptions import DCSError, PostgresConnectionException, PatroniException
+from patroni.exceptions import DCSError, PostgresConnectionException, PatroniFatalException
 from patroni.postgresql import ACTION_ON_START, ACTION_ON_ROLE_CHANGE
 from patroni.postgresql.misc import postgres_version_to_int
 from patroni.postgresql.rewind import Rewind
-from patroni.utils import polling_loop, tzutc
+from patroni.utils import polling_loop, tzutc, is_standby_cluster as _is_standby_cluster, parse_int
 from patroni.dcs import RemoteMember
 from threading import RLock
 
@@ -71,7 +70,7 @@ class Ha(object):
         self._was_paused = False
         self._leader_timeline = None
         self.recovering = False
-        self._post_bootstrap_task = None
+        self._async_response = CriticalTask()
         self._crash_recovery_executed = False
         self._start_timeout = None
         self._async_executor = AsyncExecutor(self.state_handler.cancellable, self.wakeup)
@@ -88,6 +87,9 @@ class Ha(object):
         # already running as replica was aborted due to cluster not beeing initialized in DCS.
         self._join_aborted = False
 
+        # used only in backoff after failing a pre_promote script
+        self._released_leader_key_timestamp = 0
+
     def check_mode(self, mode):
         # Try to protect from the case when DCS was wiped out during pause
         if self.cluster and self.cluster.config and self.cluster.config.modify_index:
@@ -95,6 +97,11 @@ class Ha(object):
         else:
             return self.patroni.config.check_mode(mode)
 
+    def master_stop_timeout(self):
+        """ Master stop timeout """
+        ret = parse_int(self.patroni.config['master_stop_timeout'])
+        return ret if ret and ret > 0 and self.is_synchronous_mode() else None
+
     def is_paused(self):
         return self.check_mode('pause')
 
@@ -109,9 +116,7 @@ class Ha(object):
         return config.get('standby_cluster')
 
     def is_standby_cluster(self):
-        config = self.get_standby_cluster_config()
+        return _is_standby_cluster(self.get_standby_cluster_config())
-        # Check whether or not provided configuration describes a standby cluster
-        return isinstance(config, dict) and (config.get('host') or config.get('port') or config.get('restore_command'))
 
     def is_leader(self):
         with self._is_leader_lock:
@@ -194,9 +199,21 @@ class Ha(object):
             if self._async_executor.scheduled_action in (None, 'promote') \
                     and data['state'] in ['running', 'restarting', 'starting']:
                 try:
-                    timeline, wal_position = self.state_handler.timeline_wal_position()
+                    timeline, wal_position, pg_control_timeline = self.state_handler.timeline_wal_position()
                     data['xlog_location'] = wal_position
+                    if not timeline:  # try pg_stat_wal_receiver to get the timeline
+                        timeline = self.state_handler.received_timeline()
                     if not timeline:
+                        # So far the only way to get the current timeline on the standby is from
+                        # the replication connection. In order to avoid opening the replication
+                        # connection on every iteration of HA loop we will do it only when noticed
+                        # that the timeline on the primary has changed.
+                        # Unfortunately such optimization isn't possible on the standby_leader,
+                        # therefore we will get the timeline from pg_control, either by calling
+                        # pg_control_checkpoint() on 9.6+ or by parsing the output of pg_controldata.
+                        if self.state_handler.role == 'standby_leader':
+                            timeline = pg_control_timeline or self.state_handler.pg_control_timeline()
+                        else:
                             timeline = self.state_handler.replica_cached_timeline(self._leader_timeline)
                     if timeline:
                         data['timeline'] = timeline
@@ -231,27 +248,23 @@ class Ha(object):
             clone_member = self.cluster.get_clone_member(self.state_handler.name)
             member_role = 'leader' if clone_member == self.cluster.leader else 'replica'
             msg = "from {0} '{1}'".format(member_role, clone_member.name)
-            self._async_executor.schedule('bootstrap {0}'.format(msg))
+            ret = self._async_executor.try_run_async('bootstrap {0}'.format(msg), self.clone, args=(clone_member, msg))
-            self._async_executor.run_async(self.clone, args=(clone_member, msg))
+            return ret or 'trying to bootstrap {0}'.format(msg)
-            return 'trying to bootstrap {0}'.format(msg)
 
         # no initialize key and node is allowed to be master and has 'bootstrap' section in a configuration file
         elif self.cluster.initialize is None and not self.patroni.nofailover and 'bootstrap' in self.patroni.config:
             if self.dcs.initialize(create_new=True):  # race for initialization
                 self.state_handler.bootstrapping = True
-                self._post_bootstrap_task = CriticalTask()
+                with self._async_response:
+                    self._async_response.reset()
 
                 if self.is_standby_cluster():
-                    self._async_executor.schedule('bootstrap_standby_leader')
+                    ret = self._async_executor.try_run_async('bootstrap_standby_leader', self.bootstrap_standby_leader)
-                    self._async_executor.run_async(self.bootstrap_standby_leader)
+                    return ret or 'trying to bootstrap a new standby leader'
-                    return 'trying to bootstrap a new standby leader'
                 else:
-                    self._async_executor.schedule('bootstrap')
+                    ret = self._async_executor.try_run_async('bootstrap', self.state_handler.bootstrap.bootstrap,
-                    self._async_executor.run_async(
+                                                             args=(self.patroni.config['bootstrap'],))
-                        self.state_handler.bootstrap.bootstrap,
+                    return ret or 'trying to bootstrap a new cluster'
-                        args=(self.patroni.config['bootstrap'],)
-                    )
-                    return 'trying to bootstrap a new cluster'
             else:
                 return 'failed to acquire initialize lock'
         else:
@@ -259,9 +272,7 @@ class Ha(object):
                                      if self.is_standby_cluster() else None
             if self.state_handler.can_create_replica_without_replication_connection(create_replica_methods):
                 msg = 'bootstrap (without leader)'
-                self._async_executor.schedule(msg)
+                return self._async_executor.try_run_async(msg, self.clone) or 'trying to ' + msg
-                self._async_executor.run_async(self.clone)
-                return 'trying to ' + msg
             return 'waiting for {0}leader to bootstrap'.format('standby_' if self.is_standby_cluster() else '')
 
     def bootstrap_standby_leader(self):
@@ -272,7 +283,8 @@ class Ha(object):
         clone_source = self.get_remote_master()
         msg = 'clone from remote master {0}'.format(clone_source.conn_url)
         result = self.clone(clone_source, msg)
-        self._post_bootstrap_task.complete(result)
+        with self._async_response:  # pretend that post_bootstrap was already executed
+            self._async_response.complete(result)
         if result:
             self.state_handler.set_role('standby_leader')
 
@@ -284,15 +296,13 @@ class Ha(object):
             return None
 
         if self._rewind.can_rewind:
-            self._async_executor.schedule('running pg_rewind from ' + leader.name)
+            msg = 'running pg_rewind from ' + leader.name
-            self._async_executor.run_async(self._rewind.execute, (leader,))
+            return self._async_executor.try_run_async(msg, self._rewind.execute, args=(leader,)) or msg
-            return True
 
         # remove_data_directory_on_diverged_timelines is set
         if not self.is_standby_cluster():
-            self._async_executor.schedule('reinitializing due to diverged timelines')
+            msg = 'reinitializing due to diverged timelines'
-            self._async_executor.run_async(self._do_reinitialize, args=(self.cluster, ))
+            return self._async_executor.try_run_async(msg, self._do_reinitialize, args=(self.cluster,)) or msg
-            return True
 
     def recover(self):
         # Postgres is not running and we will restart in standby mode. Watchdog is not needed until we promote.
@@ -319,9 +329,8 @@ class Ha(object):
                 and not self._crash_recovery_executed and \
                 (self.cluster.is_unlocked() or self._rewind.can_rewind):
             self._crash_recovery_executed = True
-            self._async_executor.schedule('doing crash recovery in a single user mode')
+            msg = 'doing crash recovery in a single user mode'
-            self._async_executor.run_async(self.state_handler.fix_cluster_state)
+            return self._async_executor.try_run_async(msg, self._rewind.ensure_clean_shutdown) or msg
-            return self._async_executor.scheduled_action
 
         self.load_cluster_from_dcs()
 
@@ -329,8 +338,9 @@ class Ha(object):
         if self.is_standby_cluster() or not self.has_lock():
             if not self._rewind.executed:
                 self._rewind.trigger_check_diverged_lsn()
-            if self._handle_rewind_or_reinitialize():
+            msg = self._handle_rewind_or_reinitialize()
-                return self._async_executor.scheduled_action
+            if msg:
+                return msg
 
             if self.has_lock():  # in standby cluster
                 msg = "starting as a standby leader because i had the session lock"
@@ -346,23 +356,34 @@ class Ha(object):
             msg = "starting as readonly because i had the session lock"
             node_to_follow = None
 
+        if self._async_executor.try_run_async('restarting after failure', self.state_handler.follow,
+                                              args=(node_to_follow, role, timeout)) is None:
             self.recovering = True
-
-        self._async_executor.schedule('restarting after failure')
-        self._async_executor.run_async(self.state_handler.follow, (node_to_follow, role, timeout))
         return msg
 
     def _get_node_to_follow(self, cluster):
         # determine the node to follow. If replicatefrom tag is set,
         # try to follow the node mentioned there, otherwise, follow the leader.
-        if self.is_standby_cluster() and (self.cluster.is_unlocked() or self.has_lock(False)):
+        standby_config = self.get_standby_cluster_config()
+        is_standby_cluster = _is_standby_cluster(standby_config)
+        if is_standby_cluster and (self.cluster.is_unlocked() or self.has_lock(False)):
             node_to_follow = self.get_remote_master()
         elif self.patroni.replicatefrom and self.patroni.replicatefrom != self.state_handler.name:
             node_to_follow = cluster.get_member(self.patroni.replicatefrom)
         else:
-            node_to_follow = cluster.leader
+            node_to_follow = cluster.leader if cluster.leader and cluster.leader.name else None
 
-        return node_to_follow if node_to_follow and node_to_follow.name != self.state_handler.name else None
+        node_to_follow = node_to_follow if node_to_follow and node_to_follow.name != self.state_handler.name else None
+
+        if node_to_follow and not isinstance(node_to_follow, RemoteMember):
+            # we are going to abuse Member.data to pass following parameters
+            params = ('restore_command', 'archive_cleanup_command')
+            for param in params:  # It is highly unlikely to happen, but we want to protect from the case
+                node_to_follow.data.pop(param, None)  # when above-mentioned params came from outside.
+            if is_standby_cluster:
+                node_to_follow.data.update({p: standby_config[p] for p in params if standby_config.get(p)})
+
+        return node_to_follow
 
     def follow(self, demote_reason, follow_reason, refresh=True):
         if refresh:
@@ -375,26 +396,40 @@ class Ha(object):
         if self.is_paused():
             if not (self._rewind.is_needed and self._rewind.can_rewind_or_reinitialize_allowed)\
                     or self.cluster.is_unlocked():
-                self.state_handler.set_role('master' if is_leader else 'replica')
                 if is_leader:
+                    self.state_handler.set_role('master')
                     return 'continue to run as master without lock'
-                elif not node_to_follow:
+                elif self.state_handler.role != 'standby_leader':
+                    self.state_handler.set_role('replica')
+
+                if not node_to_follow:
                     return 'no action'
         elif is_leader:
             self.demote('immediate-nolock')
             return demote_reason
 
-        if self._handle_rewind_or_reinitialize():
+        if self.is_standby_cluster() and self._leader_timeline and \
-            return self._async_executor.scheduled_action
+                self.state_handler.get_history(self._leader_timeline + 1):
+            self._rewind.trigger_check_diverged_lsn()
+
+        msg = self._handle_rewind_or_reinitialize()
+        if msg:
+            return msg
 
         role = 'standby_leader' if isinstance(node_to_follow, RemoteMember) and self.has_lock(False) else 'replica'
         # It might happen that leader key in the standby cluster references non-exiting member.
         # In this case it is safe to continue running without changing recovery.conf
         if self.is_standby_cluster() and role == 'replica' and not (node_to_follow and node_to_follow.conn_url):
             return 'continue following the old known standby leader'
-        elif not self.state_handler.config.check_recovery_conf(node_to_follow):
+        else:
-            self._async_executor.schedule('changing primary_conninfo and restarting')
+            change_required, restart_required = self.state_handler.config.check_recovery_conf(node_to_follow)
-            self._async_executor.run_async(self.state_handler.follow, (node_to_follow, role))
+            if change_required:
+                if restart_required:
+                    self._async_executor.try_run_async('changing primary_conninfo and restarting',
+                                                       self.state_handler.follow, args=(node_to_follow, role))
+                else:
+                    self.state_handler.follow(node_to_follow, role, do_reload=True)
+                self._rewind.trigger_check_diverged_lsn()
             elif role == 'standby_leader' and self.state_handler.role != role:
                 self.state_handler.set_role(role)
                 self.state_handler.call_nowait(ACTION_ON_ROLE_CHANGE)
@@ -417,28 +452,34 @@ class Ha(object):
         promoting standbys that were guaranteed to be replicating synchronously.
         """
         if self.is_synchronous_mode():
-            current = self.cluster.sync.leader and self.cluster.sync.sync_standby
+            sync_node_count = self.patroni.config['synchronous_node_count']
-            picked, allow_promote = self.state_handler.pick_synchronous_standby(self.cluster)
+            current = self.cluster.sync.leader and self.cluster.sync.members or []
-            if picked != current:
+            picked, allow_promote = self.state_handler.pick_synchronous_standby(self.cluster, sync_node_count)
-                # We need to revoke privilege from current before replacing it in the config
+            if set(picked) != set(current):
-                if current:
+                # update synchronous standby list in dcs temporarily to point to common nodes in current and picked
-                    logger.info("Removing synchronous privilege from %s", current)
+                sync_common = list(set(current).intersection(set(allow_promote)))
-                    if not self.dcs.write_sync_state(self.state_handler.name, None, index=self.cluster.sync.index):
+                if set(sync_common) != set(current):
+                    logger.info("Updating synchronous privilege temporarily from %s to %s", current, sync_common)
+                    if not self.dcs.write_sync_state(self.state_handler.name,
+                                                     sync_common or None,
+                                                     index=self.cluster.sync.index):
                         logger.info('Synchronous replication key updated by someone else.')
                         return
 
-                if self.is_synchronous_mode_strict() and picked is None:
+                # Update  db param and wait for x secs
-                    picked = '*'
+                if self.is_synchronous_mode_strict() and not picked:
+                    picked = ['*']
                     logger.warning("No standbys available!")
 
                 logger.info("Assigning synchronous standby status to %s", picked)
                 self.state_handler.config.set_synchronous_standby(picked)
 
-                if picked and picked != '*' and not allow_promote:
+                if picked and picked[0] != '*' and set(allow_promote) != set(picked) and not allow_promote:
                     # Wait for PostgreSQL to enable synchronous mode and see if we can immediately set sync_standby
                     time.sleep(2)
-                    picked, allow_promote = self.state_handler.pick_synchronous_standby(self.cluster)
+                    _, allow_promote = self.state_handler.pick_synchronous_standby(self.cluster,
-                if allow_promote:
+                                                                                   sync_node_count)
+                if allow_promote and set(allow_promote) != set(sync_common):
                     try:
                         cluster = self.dcs.get_cluster()
                     except DCSError:
@@ -446,18 +487,18 @@ class Ha(object):
                     if cluster.sync.leader and cluster.sync.leader != self.state_handler.name:
                         logger.info("Synchronous replication key updated by someone else")
                         return
-                    if not self.dcs.write_sync_state(self.state_handler.name, picked, index=cluster.sync.index):
+                    if not self.dcs.write_sync_state(self.state_handler.name, allow_promote, index=cluster.sync.index):
                         logger.info("Synchronous replication key updated by someone else")
                         return
-                    logger.info("Synchronous standby status assigned to %s", picked)
+                    logger.info("Synchronous standby status assigned to %s", allow_promote)
         else:
             if self.cluster.sync.leader and self.dcs.delete_sync_state(index=self.cluster.sync.index):
                 logger.info("Disabled synchronous replication")
-            self.state_handler.config.set_synchronous_standby(None)
+            self.state_handler.config.set_synchronous_standby([])
 
     def is_sync_standby(self, cluster):
         return cluster.leader and cluster.sync.leader == cluster.leader.name \
-            and cluster.sync.sync_standby == self.state_handler.name
+            and self.state_handler.name in cluster.sync.members
 
     def while_not_sync_standby(self, func):
         """Runs specified action while trying to make sure that the node is not assigned synchronous standby status.
@@ -503,9 +544,10 @@ class Ha(object):
             if cluster_history:
                 self.dcs.set_history_value('[]')
         elif not cluster_history or cluster_history[-1][0] != master_timeline - 1 or len(cluster_history[-1]) != 4:
-            cluster_history = {l[0]: l for l in cluster_history or []}
+            cluster_history = {line[0]: line for line in cluster_history or []}
             history = self.state_handler.get_history(master_timeline)
-            if history:
+            if history and self.cluster.config:
+                history = history[-self.cluster.config.max_timelines_history:]
                 for line in history:
                     # enrich current history with promotion timestamps stored in DCS
                     if len(line) == 3 and line[0] in cluster_history \
@@ -519,7 +561,12 @@ class Ha(object):
         return self.follow(demote_reason, message)
 
     def enforce_master_role(self, message, promote_message):
-        if not self.is_paused() and not self.watchdog.is_running and not self.watchdog.activate():
+        """
+        Ensure the node that has won the race for the leader key meets criteria
+        for promoting its PG server to the 'master' role.
+        """
+        if not self.is_paused():
+            if not self.watchdog.is_running and not self.watchdog.activate():
                 if self.state_handler.is_leader():
                     self.demote('immediate')
                     return 'Demoting self because watchdog could not be activated'
@@ -527,6 +574,15 @@ class Ha(object):
                     self.release_leader_key_voluntarily()
                     return 'Not promoting self because watchdog could not be activated'
 
+            with self._async_response:
+                if self._async_response.result is False:
+                    logger.warning("Releasing the leader key voluntarily because the pre-promote script failed")
+                    self._released_leader_key_timestamp = time.time()
+                    self.release_leader_key_voluntarily()
+                    # discard the result of the failed pre-promote script to be able to re-try promote
+                    self._async_response.reset()
+                    return 'Promotion cancelled because the pre-promote script failed'
+
         if self.state_handler.is_leader():
             # Inform the state handler about its master role.
             # It may be unaware of it if postgres is promoted manually.
@@ -545,7 +601,7 @@ class Ha(object):
                     # Somebody else updated sync state, it may be due to us losing the lock. To be safe, postpone
                     # promotion until next cycle. TODO: trigger immediate retry of run_cycle
                     return 'Postponing promotion because synchronous replication state was updated by somebody else'
-                self.state_handler.config.set_synchronous_standby('*' if self.is_synchronous_mode_strict() else None)
+                self.state_handler.config.set_synchronous_standby(['*'] if self.is_synchronous_mode_strict() else [])
             if self.state_handler.role != 'master':
                 self.set_leader_access_is_restricted(self.cluster.has_permanent_logical_slots(self.state_handler.name))
 
@@ -553,21 +609,23 @@ class Ha(object):
                     self._rewind.reset_state()
                     logger.info("cleared rewind state after becoming the leader")
 
-                self._async_executor.schedule('promote')
+                with self._async_response:
-                self._async_executor.run_async(self.state_handler.promote,
+                    self._async_response.reset()
-                                               args=(self.dcs.loop_wait, on_success, self._leader_access_is_restricted))
+                self._async_executor.try_run_async('promote', self.state_handler.promote,
+                                                   args=(self.dcs.loop_wait, self._async_response, on_success,
+                                                         self._leader_access_is_restricted))
             return promote_message
 
-    @staticmethod
+    def fetch_node_status(self, member):
-    def fetch_node_status(member):
         """This function perform http get request on member.api_url and fetches its status
         :returns: `_MemberStatus` object
         """
 
         try:
-            response = requests.get(member.api_url, timeout=2, verify=False)
+            response = self.patroni.request(member, timeout=2, retries=0)
-            logger.info('Got response from %s %s: %s', member.name, member.api_url, response.content)
+            data = response.data.decode('utf-8')
-            return _MemberStatus.from_api_response(member, response.json())
+            logger.info('Got response from %s %s: %s', member.name, member.api_url, data)
+            return _MemberStatus.from_api_response(member, json.loads(data))
         except Exception as e:
             logger.warning("Request failed to %s: GET %s (%s)", member.name, member.api_url, e)
         return _MemberStatus.unknown(member)
@@ -591,7 +649,8 @@ class Ha(object):
     def _is_healthiest_node(self, members, check_replication_lag=True):
         """This method tries to determine whether I am healthy enough to became a new leader candidate or not."""
 
-        _, my_wal_position = self.state_handler.timeline_wal_position()
+        # We don't call `last_operation()` here because it returns a string
+        _, my_wal_position, _ = self.state_handler.timeline_wal_position()
         if check_replication_lag and self.is_lagging(my_wal_position):
             logger.info('My wal position exceeds maximum replication lag')
             return False  # Too far behind last reported wal position on master
@@ -689,6 +748,10 @@ class Ha(object):
         return self._is_healthiest_node(members, check_replication_lag=False)
 
     def is_healthiest_node(self):
+        if time.time() - self._released_leader_key_timestamp < self.dcs.ttl:
+            logger.info('backoff: skip leader race after pre_promote script failure and releasing the lock voluntarily')
+            return False
+
         if self.is_paused() and not self.patroni.nofailover and \
                 self.cluster.failover and not self.cluster.failover.scheduled_at:
             ret = self.manual_failover_process_no_leader()
@@ -726,13 +789,13 @@ class Ha(object):
 
         return self._is_healthiest_node(members.values())
 
-    def _delete_leader(self):
+    def _delete_leader(self, last_operation=None):
         self.set_is_leader(False)
-        self.dcs.delete_leader()
+        self.dcs.delete_leader(last_operation)
         self.dcs.reset_cluster()
 
-    def release_leader_key_voluntarily(self):
+    def release_leader_key_voluntarily(self, last_operation=None):
-        self._delete_leader()
+        self._delete_leader(last_operation)
         self.touch_member()
         logger.info("Leader key released")
 
@@ -756,13 +819,15 @@ class Ha(object):
 
         self._rewind.trigger_check_diverged_lsn()
         self.state_handler.stop(mode_control['stop'], checkpoint=mode_control['checkpoint'],
-                                on_safepoint=self.watchdog.disable if self.watchdog.is_running else None)
+                                on_safepoint=self.watchdog.disable if self.watchdog.is_running else None,
+                                stop_timeout=self.master_stop_timeout())
         self.state_handler.set_role('demoted')
         self.set_is_leader(False)
 
         if mode_control['release']:
+            checkpoint_location = self.state_handler.latest_checkpoint_location() if mode == 'graceful' else None
             with self._async_executor:
-                self.release_leader_key_voluntarily()
+                self.release_leader_key_voluntarily(checkpoint_location)
             time.sleep(2)  # Give a time to somebody to take the leader lock
         if mode_control['offline']:
             node_to_follow, leader = None, None
@@ -774,11 +839,10 @@ class Ha(object):
         # there could be an async action already running, calling follow from here will lead
         # to racy state handler state updates.
         if mode_control['async_req']:
-            self._async_executor.schedule('starting after demotion')
+            self._async_executor.try_run_async('starting after demotion', self.state_handler.follow, (node_to_follow,))
-            self._async_executor.run_async(self.state_handler.follow, (node_to_follow,))
         else:
             if self.is_synchronous_mode():
-                self.state_handler.config.set_synchronous_standby(None)
+                self.state_handler.config.set_synchronous_standby([])
             if self._rewind.rewind_or_reinitialize_needed_and_possible(leader):
                 return False  # do not start postgres, but run pg_rewind on the next iteration
             self.state_handler.follow(node_to_follow)
@@ -839,7 +903,7 @@ class Ha(object):
                 else:
                     if self.is_synchronous_mode():
                         if failover.candidate and not self.cluster.sync.matches(failover.candidate):
-                            logger.warning('Failover candidate=%s does not match with sync_standby=%s',
+                            logger.warning('Failover candidate=%s does not match with sync_standbys=%s',
                                            failover.candidate, self.cluster.sync.sync_standby)
                             members = []
                         else:
@@ -848,9 +912,8 @@ class Ha(object):
                         members = [m for m in self.cluster.members
                                    if not failover.candidate or m.name == failover.candidate]
                     if self.is_failover_possible(members):  # check that there are healthy members
-                        self._async_executor.schedule('manual failover: demote')
+                        ret = self._async_executor.try_run_async('manual failover: demote', self.demote, ('graceful',))
-                        self._async_executor.run_async(self.demote, ('graceful',))
+                        return ret or 'manual failover: demoting myself'
-                        return 'manual failover: demoting myself'
                     else:
                         logger.warning('manual failover: no healthy members found, failover is not possible')
             else:
@@ -878,9 +941,9 @@ class Ha(object):
                 self.load_cluster_from_dcs()
 
                 if self.is_standby_cluster():
-                    # standby leader disappeared, and this is a healthiest
+                    # standby leader disappeared, and this is the healthiest
                     # replica, so it should become a new standby leader.
-                    # This imply that we need to start following a remote master
+                    # This implies we need to start following a remote master
                     msg = 'promoted self to a standby leader by acquiring session lock'
                     return self.enforce_follow_remote_master(msg)
                 else:
@@ -924,7 +987,7 @@ class Ha(object):
                     return msg
 
                 # check if the node is ready to be used by pg_rewind
-                self._rewind.check_for_checkpoint_after_promote()
+                self._rewind.ensure_checkpoint_after_promote(self.wakeup)
 
                 if self.is_standby_cluster():
                     # in case of standby cluster we don't really need to
@@ -1069,7 +1132,7 @@ class Ha(object):
                 return (False, 'restart failed')
 
     def _do_reinitialize(self, cluster):
-        self.state_handler.stop('immediate')
+        self.state_handler.stop('immediate', stop_timeout=self.patroni.config['retry_timeout'])
         # Commented redundant data directory cleanup here
         # self.state_handler.remove_data_directory()
 
@@ -1098,10 +1161,20 @@ class Ha(object):
         self._async_executor.run_async(self._do_reinitialize, args=(self.cluster, ))
 
     def handle_long_action_in_progress(self):
+        """
+        Figure out what to do with the task AsyncExecutor is performing.
+        """
         if self.has_lock() and self.update_lock():
             return 'updated leader lock during ' + self._async_executor.scheduled_action
         elif not self.state_handler.bootstrapping:
-            # Don't have lock, make sure we are not starting up a master in the background
+            # Don't have lock, make sure we are not promoting or starting up a master in the background
+            if self._async_executor.scheduled_action == 'promote':
+                with self._async_response:
+                    cancel = self._async_response.cancel()
+                if cancel:
+                    self.state_handler.cancellable.cancel()
+                    return 'lost leader before promote'
+
             if self.state_handler.role == 'master':
                 logger.info("Demoting master during " + self._async_executor.scheduled_action)
                 if self._async_executor.scheduled_action == 'restart':
@@ -1112,7 +1185,6 @@ class Ha(object):
                             self.state_handler.terminate_starting_postmaster(postmaster=task.result)
                 self.demote('immediate-nolock')
                 return 'lost leader lock during ' + self._async_executor.scheduled_action
-
         if self.cluster.is_unlocked():
             logger.info('not healthy enough for leader race')
 
@@ -1129,40 +1201,45 @@ class Ha(object):
         if not self.state_handler.is_running():
             self.watchdog.disable()
             if self.has_lock():
+                if self.state_handler.role in ('master', 'standby_leader'):
                     self.state_handler.set_role('demoted')
                 self._delete_leader()
                 return 'removed leader key after trying and failing to start postgres'
             return 'failed to start postgres'
         self._crash_recovery_executed = False
+        if self._rewind.executed and not self._rewind.failed:
+            self._rewind.reset_state()
         return None
 
     def cancel_initialization(self):
         logger.info('removing initialize key after failed attempt to bootstrap the cluster')
         self.dcs.cancel_initialization()
-        self.state_handler.stop('immediate')
+        self.state_handler.stop('immediate', stop_timeout=self.patroni.config['retry_timeout'])
         self.state_handler.move_data_directory()
-        raise PatroniException('Failed to bootstrap cluster')
+        raise PatroniFatalException('Failed to bootstrap cluster')
 
     def post_bootstrap(self):
+        with self._async_response:
+            result = self._async_response.result
         # bootstrap has failed if postgres is not running
-        if not self.state_handler.is_running() or self._post_bootstrap_task.result is False:
+        if not self.state_handler.is_running() or result is False:
             self.cancel_initialization()
 
-        if self._post_bootstrap_task.result is None:
+        if result is None:
             if not self.state_handler.is_leader():
                 return 'waiting for end of recovery after bootstrap'
 
             self.state_handler.set_role('master')
-            self._async_executor.schedule('post_bootstrap')
+            ret = self._async_executor.try_run_async('post_bootstrap', self.state_handler.bootstrap.post_bootstrap,
-            self._async_executor.run_async(self.state_handler.bootstrap.post_bootstrap,
+                                                     args=(self.patroni.config['bootstrap'], self._async_response))
-                                           args=(self.patroni.config['bootstrap'], self._post_bootstrap_task))
+            return ret or 'running post_bootstrap'
-            return 'running post_bootstrap'
 
         self.state_handler.bootstrapping = False
-        self.dcs.set_config_value(json.dumps(self.patroni.config.dynamic_configuration, separators=(',', ':')))
         if not self.watchdog.activate():
             logger.error('Cancelling bootstrap because watchdog activation failed')
             self.cancel_initialization()
+        self.dcs.initialize(create_new=(self.cluster.initialize is None), sysid=self.state_handler.sysid)
+        self.dcs.set_config_value(json.dumps(self.patroni.config.dynamic_configuration, separators=(',', ':')))
         self.state_handler.slots_handler.sync_replication_slots(self.cluster)
         self.dcs.take_leader()
         self.set_is_leader(True)
@@ -1262,7 +1339,7 @@ class Ha(object):
             # is data directory empty?
             if self.state_handler.data_directory_empty():
                 self.state_handler.set_role('uninitialized')
-                self.state_handler.stop('immediate')
+                self.state_handler.stop('immediate', stop_timeout=self.patroni.config['retry_timeout'])
                 # In case datadir went away while we were master.
                 self.watchdog.disable()
 
@@ -1272,29 +1349,32 @@ class Ha(object):
                     return 'released leader key voluntarily as data dir empty and currently leader'
 
                 return self.bootstrap()  # new node
+            else:
+                # check if we are allowed to join
+                data_sysid = self.state_handler.sysid
+                if not self.sysid_valid(data_sysid):
+                    # data directory is not empty, but no valid sysid, cluster must be broken, suggest reinit
+                    return ("data dir for the cluster is not empty, "
+                            "but system ID is invalid; consider doing reinitialize")
+
+                if self.sysid_valid(self.cluster.initialize):
+                    if self.cluster.initialize != data_sysid:
+                        logger.fatal("system ID mismatch, node %s belongs to a different cluster: %s != %s",
+                                     self.state_handler.name, self.cluster.initialize, data_sysid)
+                        sys.exit(1)
+                elif self.cluster.is_unlocked() and not self.is_paused():
                     # "bootstrap", but data directory is not empty
-            elif not self.sysid_valid(self.cluster.initialize) and self.cluster.is_unlocked() and not self.is_paused():
                     if not self.state_handler.cb_called and self.state_handler.is_running() \
                             and not self.state_handler.is_leader():
                         self._join_aborted = True
                         logger.error('No initialize key in DCS and PostgreSQL is running as replica, aborting start')
                         logger.error('Please first start Patroni on the node running as master')
                         sys.exit(1)
-                self.dcs.initialize(create_new=(self.cluster.initialize is None), sysid=self.state_handler.sysid)
+                    self.dcs.initialize(create_new=(self.cluster.initialize is None), sysid=data_sysid)
-            else:
-                # check if we are allowed to join
-                data_sysid = self.state_handler.sysid
-                if not self.sysid_valid(data_sysid):
-                    # data directory is not empty, but no valid sysid, cluster must be broken, suggest reinit
-                    return "data dir for the cluster is not empty, but system ID is invalid; consider doing reinitalize"
-
-                if self.sysid_valid(self.cluster.initialize) and self.cluster.initialize != self.state_handler.sysid:
-                    logger.fatal("system ID mismatch, node %s belongs to a different cluster: %s != %s",
-                                 self.state_handler.name, self.cluster.initialize, self.state_handler.sysid)
-                    sys.exit(1)
 
             if not self.state_handler.is_healthy():
                 if self.is_paused():
+                    self.state_handler.set_state('stopped')
                     if self.has_lock():
                         self._delete_leader()
                         return 'removed leader lock because postgres is not running'
@@ -1307,6 +1387,8 @@ class Ha(object):
                             (self._rewind.is_needed and self._rewind.can_rewind_or_reinitialize_allowed):
                         return 'postgres is not running'
 
+                if self.state_handler.state in ('running', 'starting'):
+                    self.state_handler.set_state('crashed')
                 # try to start dead postgres
                 return self.recover()
 
@@ -1341,8 +1423,14 @@ class Ha(object):
 
     def run_cycle(self):
         with self._async_executor:
+            try:
                 info = self._run_cycle()
                 return (self.is_paused() and 'PAUSE: ' or '') + info
+            except PatroniFatalException:
+                raise
+            except Exception:
+                logger.exception('Unexpected exception')
+                return 'Unexpected exception raised, please report it as a BUG'
 
     def shutdown(self):
         if self.is_paused():
@@ -1354,10 +1442,12 @@ class Ha(object):
             # This might not be the desired behavior of users, as a graceful shutdown of the host can mean lost data.
             # We probably need to something smarter here.
             disable_wd = self.watchdog.disable if self.watchdog.is_running else None
-            self.while_not_sync_standby(lambda: self.state_handler.stop(checkpoint=False, on_safepoint=disable_wd))
+            self.while_not_sync_standby(lambda: self.state_handler.stop(checkpoint=False, on_safepoint=disable_wd,
+                                                                        stop_timeout=self.master_stop_timeout()))
             if not self.state_handler.is_running():
-                if self.has_lock():
+                if self.is_leader():
-                    self.dcs.delete_leader()
+                    checkpoint_location = self.state_handler.latest_checkpoint_location()
+                    self.dcs.delete_leader(checkpoint_location)
                 self.touch_member()
             else:
                 # XXX: what about when Patroni is started as the wrong user that has access to the watchdog device
@@ -1368,7 +1458,7 @@ class Ha(object):
 
     def watch(self, timeout):
         # watch on leader key changes if the postgres is running and leader is known and current node is not lock owner
-        if self._async_executor.busy or self.cluster.is_unlocked() or self.has_lock(False):
+        if self._async_executor.busy or not self.cluster or self.cluster.is_unlocked() or self.has_lock(False):
             leader_index = None
         else:
             leader_index = self.cluster.leader.index

patroni/log.py

@@ -11,6 +11,20 @@ from threading import Lock, Thread
 _LOGGER = logging.getLogger(__name__)
 
 
+def debug_exception(logger_obj, msg, *args, **kwargs):
+    kwargs.pop("exc_info", False)
+    if logger_obj.isEnabledFor(logging.DEBUG):
+        logger_obj.debug(msg, *args, exc_info=True, **kwargs)
+    else:
+        msg = "{0}, DETAIL: '{1}'".format(msg, sys.exc_info()[1])
+        logger_obj.error(msg, *args, exc_info=False, **kwargs)
+
+
+def error_exception(logger_obj, msg, *args, **kwargs):
+    exc_info = kwargs.pop("exc_info", True)
+    logger_obj.error(msg, *args, exc_info=exc_info, **kwargs)
+
+
 class QueueHandler(logging.Handler):
 
     def __init__(self):
@@ -48,9 +62,20 @@ class QueueHandler(logging.Handler):
         return self._records_lost
 
 
+class ProxyHandler(logging.Handler):
+
+    def __init__(self, patroni_logger):
+        logging.Handler.__init__(self)
+        self.patroni_logger = patroni_logger
+
+    def emit(self, record):
+        self.patroni_logger.log_handler.handle(record)
+
+
 class PatroniLogger(Thread):
 
     DEFAULT_LEVEL = 'INFO'
+    DEFAULT_TRACEBACK_LEVEL = 'ERROR'
     DEFAULT_FORMAT = '%(asctime)s %(levelname)s: %(message)s'
 
     NORMAL_LOG_QUEUE_SIZE = 2  # When everything goes normal Patroni writes only 2 messages per HA loop
@@ -59,16 +84,18 @@ class PatroniLogger(Thread):
 
     def __init__(self):
         super(PatroniLogger, self).__init__()
-        self.daemon = True
         self._queue_handler = QueueHandler()
         self._root_logger = logging.getLogger()
-        self._root_logger.addHandler(self._queue_handler)
         self._config = None
-        self._log_handler = None
+        self.log_handler = None
+        self.log_handler_lock = Lock()
         self._old_handlers = []
-        self._log_handler_lock = Lock()
         self.reload_config({'level': 'DEBUG'})
-        self.start()
+        # We will switch to the QueueHandler only when thread was started.
+        # This is necessary to protect from the cases when Patroni constructor
+        # failed and PatroniLogger thread remain running and prevent shutdown.
+        self._proxy_handler = ProxyHandler(self)
+        self._root_logger.addHandler(self._proxy_handler)
 
     def update_loggers(self):
         loggers = deepcopy(self._config.get('loggers') or {})
@@ -87,18 +114,22 @@ class PatroniLogger(Thread):
                 self._queue_handler.queue.maxsize = config.get('max_queue_size', self.DEFAULT_MAX_QUEUE_SIZE)
 
             self._root_logger.setLevel(config.get('level', PatroniLogger.DEFAULT_LEVEL))
+            if config.get('traceback_level', PatroniLogger.DEFAULT_TRACEBACK_LEVEL).lower() == 'debug':
+                logging.Logger.exception = debug_exception
+            else:
+                logging.Logger.exception = error_exception
 
             new_handler = None
             if 'dir' in config:
-                if not isinstance(self._log_handler, RotatingFileHandler):
+                if not isinstance(self.log_handler, RotatingFileHandler):
                     new_handler = RotatingFileHandler(os.path.join(config['dir'], __name__))
-                handler = new_handler or self._log_handler
+                handler = new_handler or self.log_handler
                 handler.maxBytes = int(config.get('file_size', 25000000))
                 handler.backupCount = int(config.get('file_num', 4))
             else:
-                if self._log_handler is None or isinstance(self._log_handler, RotatingFileHandler):
+                if self.log_handler is None or isinstance(self.log_handler, RotatingFileHandler):
                     new_handler = logging.StreamHandler()
-                handler = new_handler or self._log_handler
+                handler = new_handler or self.log_handler
 
             oldlogformat = (self._config or {}).get('format', PatroniLogger.DEFAULT_FORMAT)
             logformat = config.get('format', PatroniLogger.DEFAULT_FORMAT)
@@ -110,17 +141,17 @@ class PatroniLogger(Thread):
                 handler.setFormatter(logging.Formatter(logformat, dateformat))
 
             if new_handler:
-                with self._log_handler_lock:
+                with self.log_handler_lock:
-                    if self._log_handler:
+                    if self.log_handler:
-                        self._old_handlers.append(self._log_handler)
+                        self._old_handlers.append(self.log_handler)
-                    self._log_handler = new_handler
+                    self.log_handler = new_handler
 
             self._config = config.copy()
             self.update_loggers()
 
     def _close_old_handlers(self):
         while True:
-            with self._log_handler_lock:
+            with self.log_handler_lock:
                 if not self._old_handlers:
                     break
                 handler = self._old_handlers.pop()
@@ -130,6 +161,11 @@ class PatroniLogger(Thread):
                 _LOGGER.exception('Failed to close the old log handler %s', handler)
 
     def run(self):
+        # switch to QueueHandler only when the thread was started
+        with self.log_handler_lock:
+            self._root_logger.addHandler(self._queue_handler)
+            self._root_logger.removeHandler(self._proxy_handler)
+
         while True:
             self._close_old_handlers()
 
@@ -137,7 +173,7 @@ class PatroniLogger(Thread):
             if record is None:
                 break
 
-            self._log_handler.handle(record)
+            self.log_handler.handle(record)
             self._queue_handler.queue.task_done()
 
     def shutdown(self):

patroni/postgresql/__init__.py

@@ -8,17 +8,19 @@ import time
 
 from contextlib import contextmanager
 from copy import deepcopy
+from dateutil import tz
+from datetime import datetime
 from patroni.postgresql.callback_executor import CallbackExecutor
 from patroni.postgresql.bootstrap import Bootstrap
 from patroni.postgresql.cancellable import CancellableSubprocess
-from patroni.postgresql.config import ConfigHandler
+from patroni.postgresql.config import ConfigHandler, mtime
 from patroni.postgresql.connection import Connection, get_connection_cursor
-from patroni.postgresql.misc import parse_history, postgres_major_version_to_int
+from patroni.postgresql.misc import parse_history, parse_lsn, postgres_major_version_to_int
 from patroni.postgresql.postmaster import PostmasterProcess
 from patroni.postgresql.slots import SlotsHandler
 from patroni.exceptions import PostgresConnectionException
-from patroni.utils import Retry, RetryFailedError, polling_loop
+from patroni.utils import Retry, RetryFailedError, polling_loop, data_directory_is_empty, parse_int
-from patroni.dcs import slot_name_from_member_name, RemoteMember
+from psutil import TimeoutExpired
 from threading import current_thread, Lock
 
 
@@ -38,15 +40,6 @@ STATE_UNKNOWN = 'unknown'
 
 STOP_POLLING_INTERVAL = 1
 
-cluster_info_query = ("SELECT CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
-                      "ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
-                      "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END, "
-                      "CASE WHEN pg_catalog.pg_is_in_recovery() THEN GREATEST("
-                      " pg_catalog.pg_{0}_{1}_diff(COALESCE("
-                      "pg_catalog.pg_last_{0}_receive_{1}(), '0/0'), '0/0')::bigint,"
-                      " pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint)"
-                      "ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint END")
-
 
 @contextmanager
 def null_context():
@@ -55,12 +48,23 @@ def null_context():
 
 class Postgresql(object):
 
+    POSTMASTER_START_TIME = "pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ')"
+    TL_LSN = ("CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
+              "ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
+              "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END, "  # master timeline
+              "CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
+              "ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint END, "  # write_lsn
+              "pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint,  "
+              "pg_catalog.pg_{0}_{1}_diff(COALESCE(pg_catalog.pg_last_{0}_receive_{1}(), '0/0'), '0/0')::bigint, "
+              "pg_catalog.pg_is_in_recovery() AND pg_catalog.pg_is_{0}_replay_paused()")
+
     def __init__(self, config):
         self.name = config['name']
         self.scope = config['scope']
         self._data_dir = config['data_dir']
         self._database = config.get('database', 'postgres')
         self._version_file = os.path.join(self._data_dir, 'PG_VERSION')
+        self._pg_control = os.path.join(self._data_dir, 'global', 'pg_control')
         self._major_version = self.get_major_version()
 
         self._state_lock = Lock()
@@ -69,6 +73,7 @@ class Postgresql(object):
         self._pending_restart = False
         self._connection = Connection()
         self.config = ConfigHandler(self, config)
+        self.config.check_directories()
 
         self._bin_dir = config.get('bin_dir') or ''
         self.bootstrap = Bootstrap(self)
@@ -77,7 +82,6 @@ class Postgresql(object):
 
         self.slots_handler = SlotsHandler(self)
 
-        self._pgpass = config.get('pgpass') or os.path.join(os.path.expanduser('~'), 'pgpass')
         self._callback_executor = CallbackExecutor()
         self.__cb_called = False
         self.__cb_pending = None
@@ -133,6 +137,10 @@ class Postgresql(object):
     def callback(self):
         return self.config.get('callbacks') or {}
 
+    @property
+    def wal_dir(self):
+        return os.path.join(self._data_dir, 'pg_' + self.wal_name)
+
     @property
     def wal_name(self):
         return 'wal' if self._major_version >= 100000 else 'xlog'
@@ -141,6 +149,20 @@ class Postgresql(object):
     def lsn_name(self):
         return 'lsn' if self._major_version >= 100000 else 'location'
 
+    @property
+    def cluster_info_query(self):
+        if self._major_version >= 90600:
+            extra = (", CASE WHEN latest_end_lsn IS NULL THEN NULL ELSE received_tli END,"
+                     " slot_name, conninfo FROM pg_catalog.pg_stat_get_wal_receiver()")
+            if self.role == 'standby_leader':
+                extra = "timeline_id" + extra + ", pg_catalog.pg_control_checkpoint()"
+            else:
+                extra = "0" + extra
+        else:
+            extra = "0, NULL, NULL, NULL"
+
+        return ("SELECT " + self.TL_LSN + ", {2}").format(self.wal_name, self.lsn_name, extra)
+
     def _version_file_exists(self):
         return not self.data_directory_empty() and os.path.isfile(self._version_file)
 
@@ -188,8 +210,8 @@ class Postgresql(object):
                         3: STATE_UNKNOWN}
         return return_codes.get(ret, STATE_UNKNOWN)
 
-    def reload_config(self, config):
+    def reload_config(self, config, sighup=False):
-        self.config.reload_config(config)
+        self.config.reload_config(config, sighup)
         self._is_leader_retry.deadline = self.retry.deadline = config['retry_timeout']/2.0
 
     @property
@@ -207,7 +229,7 @@ class Postgresql(object):
         return self._sysid
 
     def get_postgres_role_from_data_directory(self):
-        if self.data_directory_empty():
+        if self.data_directory_empty() or not self.controldata():
             return 'uninitialized'
         elif self.config.recovery_conf_exists():
             return 'replica'
@@ -255,21 +277,13 @@ class Postgresql(object):
         except RetryFailedError as e:
             raise PostgresConnectionException(str(e))
 
+    def pg_control_exists(self):
+        return os.path.isfile(self._pg_control)
+
     def data_directory_empty(self):
-        return not os.path.exists(self._data_dir) or os.listdir(self._data_dir) == []
+        if self.pg_control_exists():
-
+            return False
-    def write_pgpass(self, record):
+        return data_directory_is_empty(self._data_dir)
-        if 'user' not in record or 'password' not in record:
-            return os.environ.copy()
-
-        with open(self._pgpass, 'w') as f:
-            if os.name != 'nt':
-                os.fchmod(f.fileno(), 0o600)
-            f.write('{host}:{port}:*:{user}:{password}\n'.format(**record))
-
-        env = os.environ.copy()
-        env['PGPASSFILE'] = self._pgpass
-        return env
 
     def replica_method_options(self, method):
         return deepcopy(self.config.get(method, {}))
@@ -290,10 +304,11 @@ class Postgresql(object):
 
     def _cluster_info_state_get(self, name):
         if not self._cluster_info_state:
-            stmt = cluster_info_query.format(self.wal_name, self.lsn_name)
             try:
-                result = self._is_leader_retry(self._query, stmt).fetchone()
+                result = self._is_leader_retry(self._query, self.cluster_info_query).fetchone()
-                self._cluster_info_state = dict(zip(['timeline', 'wal_position'], result))
+                self._cluster_info_state = dict(zip(['timeline', 'wal_position', 'replayed_location',
+                                                     'received_location', 'replay_paused', 'pg_control_timeline',
+                                                     'received_tli', 'slot_name', 'conninfo'], result))
             except RetryFailedError as e:  # SELECT failed two times
                 self._cluster_info_state = {'error': str(e)}
                 if not self.is_starting() and self.pg_isready() == STATE_REJECT:
@@ -304,9 +319,41 @@ class Postgresql(object):
 
         return self._cluster_info_state.get(name)
 
+    def replayed_location(self):
+        return self._cluster_info_state_get('replayed_location')
+
+    def received_location(self):
+        return self._cluster_info_state_get('received_location')
+
+    def primary_slot_name(self):
+        return self._cluster_info_state_get('slot_name')
+
+    def primary_conninfo(self):
+        return self._cluster_info_state_get('conninfo')
+
+    def received_timeline(self):
+        return self._cluster_info_state_get('received_tli')
+
     def is_leader(self):
         return bool(self._cluster_info_state_get('timeline'))
 
+    def pg_control_timeline(self):
+        try:
+            return int(self.controldata().get("Latest checkpoint's TimeLineID"))
+        except (TypeError, ValueError):
+            logger.exception('Failed to parse timeline from pg_controldata output')
+
+    def latest_checkpoint_location(self):
+        """Returns checkpoint location for the cleanly shut down primary"""
+
+        data = self.controldata()
+        lsn = data.get('Latest checkpoint location')
+        if data.get('Database cluster state') == 'shut down' and lsn:
+            try:
+                return str(parse_lsn(lsn))
+            except (IndexError, ValueError) as e:
+                logger.error('Exception when parsing lsn %s: %r', lsn, e)
+
     def is_running(self):
         """Returns PostmasterProcess if one is running on the data directory or None. If most recently seen process
         is running updates the cached process based on pid file."""
@@ -411,14 +458,19 @@ class Postgresql(object):
         self.set_state('starting')
         self._pending_restart = False
 
+        try:
             configuration = self.config.effective_configuration
+        except Exception:
+            return None
+
+        self.config.check_directories()
         self.config.write_postgresql_conf(configuration)
         self.config.resolve_connection_addresses()
         self.config.replace_pg_hba()
         self.config.replace_pg_ident()
 
         options = ['--{0}={1}'.format(p, configuration[p]) for p in self.config.CMDLINE_OPTIONS
-                   if p in configuration and p != 'wal_keep_segments']
+                   if p in configuration and p not in ('wal_keep_segments', 'wal_keep_size')]
 
         if self.cancellable.is_cancelled:
             return False
@@ -455,11 +507,13 @@ class Postgresql(object):
         else:
             return None
 
-    def checkpoint(self, connect_kwargs=None):
+    def checkpoint(self, connect_kwargs=None, timeout=None):
         check_not_is_in_recovery = connect_kwargs is not None
         connect_kwargs = connect_kwargs or self.config.local_connect_kwargs
         for p in ['connect_timeout', 'options']:
             connect_kwargs.pop(p, None)
+        if timeout:
+            connect_kwargs['connect_timeout'] = timeout
         try:
             with get_connection_cursor(**connect_kwargs) as cur:
                 cur.execute("SET statement_timeout = 0")
@@ -472,7 +526,7 @@ class Postgresql(object):
             logger.exception('Exception during CHECKPOINT')
             return 'not accessible or not healty'
 
-    def stop(self, mode='fast', block_callbacks=False, checkpoint=None, on_safepoint=None):
+    def stop(self, mode='fast', block_callbacks=False, checkpoint=None, on_safepoint=None, stop_timeout=None):
         """Stop PostgreSQL
 
         Supports a callback when a safepoint is reached. A safepoint is when no user backend can return a successful
@@ -484,7 +538,7 @@ class Postgresql(object):
         if checkpoint is None:
             checkpoint = False if mode == 'immediate' else True
 
-        success, pg_signaled = self._do_stop(mode, block_callbacks, checkpoint, on_safepoint)
+        success, pg_signaled = self._do_stop(mode, block_callbacks, checkpoint, on_safepoint, stop_timeout)
         if success:
             # block_callbacks is used during restart to avoid
             # running start/stop callbacks in addition to restart ones
@@ -497,7 +551,7 @@ class Postgresql(object):
             self.set_state('stop failed')
         return success
 
-    def _do_stop(self, mode, block_callbacks, checkpoint, on_safepoint):
+    def _do_stop(self, mode, block_callbacks, checkpoint, on_safepoint, stop_timeout):
         postmaster = self.is_running()
         if not postmaster:
             if on_safepoint:
@@ -505,13 +559,13 @@ class Postgresql(object):
             return True, False
 
         if checkpoint and not self.is_starting():
-            self.checkpoint()
+            self.checkpoint(timeout=stop_timeout)
 
         if not block_callbacks:
             self.set_state('stopping')
 
         # Send signal to postmaster to stop
-        success = postmaster.signal_stop(mode)
+        success = postmaster.signal_stop(mode, self.pgcommand('pg_ctl'))
         if success is not None:
             if success and on_safepoint:
                 on_safepoint()
@@ -524,15 +578,32 @@ class Postgresql(object):
             postmaster.wait_for_user_backends_to_close()
             on_safepoint()
 
+        try:
+            postmaster.wait(timeout=stop_timeout)
+        except TimeoutExpired:
+            logger.warning("Timeout during postmaster stop, aborting Postgres.")
+            if not self.terminate_postmaster(postmaster, mode, stop_timeout):
                 postmaster.wait()
 
         return True, True
 
-    @staticmethod
+    def terminate_postmaster(self, postmaster, mode, stop_timeout):
-    def terminate_starting_postmaster(postmaster):
+        if mode in ['fast', 'smart']:
+            try:
+                success = postmaster.signal_stop('immediate', self.pgcommand('pg_ctl'))
+                if success:
+                    return True
+                postmaster.wait(timeout=stop_timeout)
+                return True
+            except TimeoutExpired:
+                pass
+        logger.warning("Sending SIGKILL to Postmaster and its children")
+        return postmaster.signal_kill()
+
+    def terminate_starting_postmaster(self, postmaster):
         """Terminates a postmaster that has not yet opened ports or possibly even written a pid file. Blocks
         until the process goes away."""
-        postmaster.signal_stop('immediate')
+        postmaster.signal_stop('immediate', self.pgcommand('pg_ctl'))
         postmaster.wait()
 
     def _wait_for_connection_close(self, postmaster):
@@ -544,9 +615,9 @@ class Postgresql(object):
         except psycopg2.Error:
             pass
 
-    def reload(self):
+    def reload(self, block_callbacks=False):
         ret = self.pg_ctl('reload')
-        if ret:
+        if ret and not block_callbacks:
             self.call_nowait(ACTION_ON_RELOAD)
         return ret
 
@@ -566,10 +637,12 @@ class Postgresql(object):
         if ready == STATE_REJECT:
             return False
         elif ready == STATE_NO_RESPONSE:
+            ret = not self.is_running()
+            if ret:
                 self.set_state('start failed')
                 self.slots_handler.schedule(False)  # TODO: can remove this?
                 self.config.save_configuration_files(True)  # TODO: maybe remove this?
-            return True
+            return ret
         else:
             if ready != STATE_RUNNING:
                 # Bad configuration or unexpected OS error. No idea of PostgreSQL status.
@@ -624,45 +697,46 @@ class Postgresql(object):
             return False
         return True
 
+    def get_guc_value(self, name):
+        cmd = [self.pgcommand('postgres'), self._data_dir, '-C', name]
+        try:
+            data = subprocess.check_output(cmd)
+            if data:
+                return data.decode('utf-8').strip()
+        except Exception as e:
+            logger.error('Failed to execute %s: %r', cmd, e)
+
     def controldata(self):
         """ return the contents of pg_controldata, or non-True value if pg_controldata call failed """
-        result = {}
         # Don't try to call pg_controldata during backup restore
         if self._version_file_exists() and self.state != 'creating replica':
             try:
-                env = {'LANG': 'C', 'LC_ALL': 'C', 'PATH': os.getenv('PATH')}
+                env = os.environ.copy()
-                if os.getenv('SYSTEMROOT') is not None:
+                env.update(LANG='C', LC_ALL='C')
-                    env['SYSTEMROOT'] = os.getenv('SYSTEMROOT')
                 data = subprocess.check_output([self.pgcommand('pg_controldata'), self._data_dir], env=env)
                 if data:
-                    data = data.decode('utf-8').splitlines()
+                    data = filter(lambda e: ':' in e, data.decode('utf-8').splitlines())
-                    # pg_controldata output depends on major verion. Some of parameters are prefixed by 'Current '
+                    # pg_controldata output depends on major version. Some of parameters are prefixed by 'Current '
-                    result = {l.split(':')[0].replace('Current ', '', 1): l.split(':', 1)[1].strip() for l in data
+                    return {k.replace('Current ', '', 1): v.strip() for k, v in map(lambda e: e.split(':', 1), data)}
-                              if l and ':' in l}
             except subprocess.CalledProcessError:
                 logger.exception("Error when calling pg_controldata")
-        return result
+        return {}
 
     @contextmanager
-    def get_replication_connection_cursor(self, host='localhost', port=5432, database=None, **kwargs):
+    def get_replication_connection_cursor(self, host='localhost', port=5432, **kwargs):
-        replication = self.config.replication
+        conn_kwargs = self.config.replication.copy()
-        with get_connection_cursor(host=host, port=int(port), database=database or self._database, replication=1,
+        conn_kwargs.update(host=host, port=int(port) if port else None, user=conn_kwargs.pop('username'),
-                                   user=replication['username'], password=replication.get('password'),
+                           connect_timeout=3, replication=1, options='-c statement_timeout=2000')
-                                   connect_timeout=3, options='-c statement_timeout=2000') as cur:
+        with get_connection_cursor(**conn_kwargs) as cur:
             yield cur
 
-    def get_local_timeline_lsn_from_replication_connection(self):
+    def get_replica_timeline(self):
-        timeline = lsn = None
         try:
             with self.get_replication_connection_cursor(**self.config.local_replication_address) as cur:
                 cur.execute('IDENTIFY_SYSTEM')
-                timeline, lsn = cur.fetchone()[1:3]
+                return cur.fetchone()[1]
         except Exception:
             logger.exception('Can not fetch local timeline and lsn from replication connection')
-        return timeline, lsn
-
-    def get_replica_timeline(self):
-        return self.get_local_timeline_lsn_from_replication_connection()[0]
 
     def replica_cached_timeline(self, master_timeline):
         if not self._cached_replica_timeline or not master_timeline or self._cached_replica_timeline != master_timeline:
@@ -673,56 +747,39 @@ class Postgresql(object):
         return self._cluster_info_state_get('timeline')
 
     def get_history(self, timeline):
-        history_path = 'pg_{0}/{1:08X}.history'.format(self.wal_name, timeline)
+        history_path = os.path.join(self.wal_dir, '{0:08X}.history'.format(timeline))
+        history_mtime = mtime(history_path)
+        if history_mtime:
             try:
-            cursor = self._connection.cursor()
+                with open(history_path, 'r') as f:
-            cursor.execute('SELECT isdir, modification FROM pg_catalog.pg_stat_file(%s)', (history_path,))
+                    history = f.read()
-            isdir, modification = cursor.fetchone()
+                history = list(parse_history(history))
-            if not isdir:
-                cursor.execute('SELECT pg_catalog.pg_read_file(%s)', (history_path,))
-                history = list(parse_history(cursor.fetchone()[0]))
                 if history[-1][0] == timeline - 1:
-                    history[-1].append(modification.isoformat())
+                    history_mtime = datetime.fromtimestamp(history_mtime).replace(tzinfo=tz.tzlocal())
+                    history[-1].append(history_mtime.isoformat())
                 return history
             except Exception:
                 logger.exception('Failed to read and parse %s', (history_path,))
 
-    def follow(self, member, role='replica', timeout=None):
+    def follow(self, member, role='replica', timeout=None, do_reload=False):
-        is_remote_master = isinstance(member, RemoteMember)
+        recovery_params = self.config.build_recovery_params(member)
-        no_replication_slot = is_remote_master and member.no_replication_slot
-        restore_command = is_remote_master and member.restore_command
-        min_apply_delay = is_remote_master and member.recovery_min_apply_delay
-        archive_cleanup = is_remote_master and member.archive_cleanup_command
-
-        primary_conninfo = self.config.primary_conninfo(member)
-        change_role = self.cb_called and (self.role in ('master', 'demoted') or
-                                          not {'standby_leader', 'replica'} - {self.role, role})
-
-        recovery_params = self.config.get('recovery_conf', {}).copy()
-        recovery_params.update({'standby_mode': 'on', 'recovery_target_timeline': 'latest'})
-        if primary_conninfo:
-            recovery_params['primary_conninfo'] = primary_conninfo
-        if self.slots_handler.use_slots and not no_replication_slot:
-            required_name = is_remote_master and member.data.get('primary_slot_name')
-            name = required_name or slot_name_from_member_name(self.name)
-            recovery_params['primary_slot_name'] = name
-        if restore_command:
-            recovery_params['restore_command'] = restore_command
-        if min_apply_delay:
-            recovery_params['recovery_min_apply_delay'] = min_apply_delay
-        if archive_cleanup:
-            recovery_params['archive_cleanup_command'] = archive_cleanup
-
         self.config.write_recovery_conf(recovery_params)
 
         # When we demoting the master or standby_leader to replica or promoting replica to a standby_leader
         # and we know for sure that postgres was already running before, we will only execute on_role_change
         # callback and prevent execution of on_restart/on_start callback.
         # If the role remains the same (replica or standby_leader), we will execute on_start or on_restart
+        change_role = self.cb_called and (self.role in ('master', 'demoted') or
+                                          not {'standby_leader', 'replica'} - {self.role, role})
         if change_role:
             self.__cb_pending = ACTION_NOOP
 
         if self.is_running():
+            if do_reload:
+                self.config.write_postgresql_conf()
+                if self.reload(block_callbacks=change_role) and change_role:
+                    self.set_role(role)
+            else:
                 self.restart(block_callbacks=change_role, role=role)
         else:
             self.start(timeout=timeout, block_callbacks=change_role, role=role)
@@ -738,9 +795,38 @@ class Postgresql(object):
             if data.get('Database cluster state') == 'in production':
                 return True
 
-    def promote(self, wait_seconds, on_success=None, access_is_restricted=False):
+    def _pre_promote(self):
+        """
+        Runs a fencing script after the leader lock is acquired but before the replica is promoted.
+        If the script exits with a non-zero code, promotion does not happen and the leader key is removed from DCS.
+        """
+
+        cmd = self.config.get('pre_promote')
+        if not cmd:
+            return True
+
+        ret = self.cancellable.call(shlex.split(cmd))
+        if ret is not None:
+            logger.info('pre_promote script `%s` exited with %s', cmd, ret)
+        return ret == 0
+
+    def promote(self, wait_seconds, task, on_success=None, access_is_restricted=False):
         if self.role == 'master':
             return True
+
+        ret = self._pre_promote()
+        with task:
+            if task.is_cancelled:
+                return False
+            task.complete(ret)
+
+        if ret is False:
+            return False
+
+        if self.cancellable.is_cancelled:
+            logger.info("PostgreSQL promote cancelled.")
+            return False
+
         ret = self.pg_ctl('promote', '-W')
         if ret:
             self.set_role('master')
@@ -751,36 +837,93 @@ class Postgresql(object):
             ret = self._wait_promote(wait_seconds)
         return ret
 
+    @staticmethod
+    def _wal_position(is_leader, wal_position, received_location, replayed_location):
+        return wal_position if is_leader else max(received_location or 0, replayed_location or 0)
+
     def timeline_wal_position(self):
         # This method could be called from different threads (simultaneously with some other `_query` calls).
         # If it is called not from main thread we will create a new cursor to execute statement.
         if current_thread().ident == self.__thread_ident:
-            return self._cluster_info_state_get('timeline'), self._cluster_info_state_get('wal_position')
+            timeline = self._cluster_info_state_get('timeline')
-
+            wal_position = self._cluster_info_state_get('wal_position')
+            replayed_location = self.replayed_location()
+            received_location = self.received_location()
+            pg_control_timeline = self._cluster_info_state_get('pg_control_timeline')
+        else:
             with self.connection().cursor() as cursor:
-            cursor.execute(cluster_info_query.format(self.wal_name, self.lsn_name))
+                cursor.execute(self.cluster_info_query)
-            return cursor.fetchone()[:2]
+                (timeline, wal_position, replayed_location,
+                 received_location, _, pg_control_timeline) = cursor.fetchone()[:6]
+
+        wal_position = self._wal_position(timeline, wal_position, received_location, replayed_location)
+        return (timeline, wal_position, pg_control_timeline)
 
     def postmaster_start_time(self):
         try:
-            cursor = self.query("SELECT pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(),"
+            query = "SELECT " + self.POSTMASTER_START_TIME
-                                " 'YYYY-MM-DD HH24:MI:SS.MS TZ')")
+            if current_thread().ident == self.__thread_ident:
+                return self.query(query).fetchone()[0]
+            with self.connection().cursor() as cursor:
+                cursor.execute(query)
                 return cursor.fetchone()[0]
         except psycopg2.Error:
             return None
 
     def last_operation(self):
-        return str(self._cluster_info_state_get('wal_position'))
+        return str(self._wal_position(self.is_leader(), self._cluster_info_state_get('wal_position'),
+                                      self.received_location(), self.replayed_location()))
 
     def configure_server_parameters(self):
         self._major_version = self.get_major_version()
         self.config.setup_server_parameters()
         return True
 
+    def pg_wal_realpath(self):
+        """Returns a dict containing the symlink (key) and target (value) for the wal directory"""
+        links = {}
+        for pg_wal_dir in ('pg_xlog', 'pg_wal'):
+            pg_wal_path = os.path.join(self._data_dir, pg_wal_dir)
+            if os.path.exists(pg_wal_path) and os.path.islink(pg_wal_path):
+                pg_wal_realpath = os.path.realpath(pg_wal_path)
+                links[pg_wal_path] = pg_wal_realpath
+        return links
+
+    def pg_tblspc_realpaths(self):
+        """Returns a dict containing the symlink (key) and target (values) for the tablespaces"""
+        links = {}
+        pg_tblsp_dir = os.path.join(self._data_dir, 'pg_tblspc')
+        if os.path.exists(pg_tblsp_dir):
+            for tsdn in os.listdir(pg_tblsp_dir):
+                pg_tsp_path = os.path.join(pg_tblsp_dir, tsdn)
+                if parse_int(tsdn) and os.path.islink(pg_tsp_path):
+                    pg_tsp_rpath = os.path.realpath(pg_tsp_path)
+                    links[pg_tsp_path] = pg_tsp_rpath
+        return links
+
     def move_data_directory(self):
         if os.path.isdir(self._data_dir) and not self.is_running():
             try:
-                new_name = '{0}_{1}'.format(self._data_dir, time.strftime('%Y-%m-%d-%H-%M-%S'))
+                postfix = time.strftime('%Y-%m-%d-%H-%M-%S')
+
+                # let's see if the wal directory is a symlink, in this case we
+                # should move the target
+                for (source, pg_wal_realpath) in self.pg_wal_realpath().items():
+                    logger.info('renaming WAL directory and updating symlink: %s', pg_wal_realpath)
+                    new_name = '{0}_{1}'.format(pg_wal_realpath, postfix)
+                    os.rename(pg_wal_realpath, new_name)
+                    os.unlink(source)
+                    os.symlink(source, new_name)
+
+                # Move user defined tablespace directory
+                for (source, pg_tsp_rpath) in self.pg_tblspc_realpaths().items():
+                    logger.info('renaming user defined tablespace directory and updating symlink: %s', pg_tsp_rpath)
+                    new_name = '{0}_{1}'.format(pg_tsp_rpath, postfix)
+                    os.rename(pg_tsp_rpath, new_name)
+                    os.unlink(source)
+                    os.symlink(source, new_name)
+
+                new_name = '{0}_{1}'.format(self._data_dir, postfix)
                 logger.info('renaming data directory to %s', new_name)
                 os.rename(self._data_dir, new_name)
             except OSError:
@@ -798,99 +941,62 @@ class Postgresql(object):
                 os.remove(self._data_dir)
             elif os.path.isdir(self._data_dir):
 
-                # let's see if pg_xlog|pg_wal is a symlink, in this case we
+                # let's see if wal directory is a symlink, in this case we
                 # should clean the target
-                for pg_wal_dir in ('pg_xlog', 'pg_wal'):
+                for pg_wal_realpath in self.pg_wal_realpath().values():
-                    pg_wal_path = os.path.join(self._data_dir, pg_wal_dir)
-                    if os.path.exists(pg_wal_path) and os.path.islink(pg_wal_path):
-                        pg_wal_realpath = os.path.realpath(pg_wal_path)
                     logger.info('Removing WAL directory: %s', pg_wal_realpath)
                     shutil.rmtree(pg_wal_realpath)
 
+                # Remove user defined tablespace directories
+                for pg_tsp_rpath in self.pg_tblspc_realpaths().values():
+                    logger.info('Removing user defined tablespace directory: %s', pg_tsp_rpath)
+                    shutil.rmtree(pg_tsp_rpath, ignore_errors=True)
+
                 shutil.rmtree(self._data_dir)
         except (IOError, OSError):
             logger.exception('Could not remove data directory %s', self._data_dir)
             self.move_data_directory()
 
-    def pick_synchronous_standby(self, cluster):
+    def _get_synchronous_commit_param(self):
+        return self.query("SHOW synchronous_commit").fetchone()[0]
+
+    def pick_synchronous_standby(self, cluster, sync_node_count=1):
         """Finds the best candidate to be the synchronous standby.
 
         Current synchronous standby is always preferred, unless it has disconnected or does not want to be a
         synchronous standby any longer.
 
-        :returns tuple of candidate name or None, and bool showing if the member is the active synchronous standby.
+        :returns tuple of candidates list and synchronous standby list.
         """
-        current = cluster.sync.sync_standby
+        if self._major_version < 90600:
-        current = current.lower() if current else current
+            sync_node_count = 1
         members = {m.name.lower(): m for m in cluster.members}
         candidates = []
-        # Pick candidates based on who has flushed WAL farthest.
+        sync_nodes = []
-        # TODO: for synchronous_commit = remote_write we actually want to order on write_location
+        # Pick candidates based on who has higher replay/remote_write/flush lsn.
+        sync_commit_par = self._get_synchronous_commit_param()
+        sort_col = {'remote_apply': 'replay', 'remote_write': 'write'}.get(sync_commit_par, 'flush')
+        # pg_stat_replication.sync_state has 4 possible states - async, potential, quorum, sync.
+        # Sort clause "ORDER BY sync_state DESC" is to get the result in required order and to keep
+        # the result consistent in case if a synchronous standby member is slowed down OR async node
+        # receiving changes faster than the sync member (very rare but possible). Such cases would
+        # trigger sync standby member swapping frequently and the sort on sync_state desc should
+        # help in keeping the query result consistent.
         for app_name, state, sync_state in self.query(
                 "SELECT pg_catalog.lower(application_name), state, sync_state"
                 " FROM pg_catalog.pg_stat_replication"
-                " ORDER BY flush_{0} DESC".format(self.lsn_name)):
+                " WHERE state = 'streaming'"
+                " ORDER BY sync_state DESC, {0}_{1} DESC".format(sort_col, self.lsn_name)):
             member = members.get(app_name)
-            if state != 'streaming' or not member or member.tags.get('nosync', False):
+            if not member or member.tags.get('nosync', False):
                 continue
+            candidates.append(member.name)
             if sync_state == 'sync':
-                return app_name, True
+                sync_nodes.append(member.name)
-            if sync_state == 'potential' and app_name == current:
+            if len(candidates) >= sync_node_count:
-                # Prefer current even if not the best one any more to avoid indecisivness and spurious swaps.
+                break
-                return current, False
-            if sync_state in ('async', 'potential'):
-                candidates.append(app_name)
 
-        if candidates:
+        return candidates, sync_nodes
-            return candidates[0], False
-        return None, False
-
-    def read_postmaster_opts(self):
-        """returns the list of option names/values from postgres.opts, Empty dict if read failed or no file"""
-        result = {}
-        try:
-            with open(os.path.join(self._data_dir, 'postmaster.opts')) as f:
-                data = f.read()
-                for opt in data.split('" "'):
-                    if '=' in opt and opt.startswith('--'):
-                        name, val = opt.split('=', 1)
-                        result[name.strip('-')] = val.rstrip('"\n')
-        except IOError:
-            logger.exception('Error when reading postmaster.opts')
-        return result
-
-    def single_user_mode(self, command=None, options=None):
-        """run a given command in a single-user mode. If the command is empty - then just start and stop"""
-        cmd = [self.pgcommand('postgres'), '--single', '-D', self._data_dir]
-        for opt, val in sorted((options or {}).items()):
-            cmd.extend(['-c', '{0}={1}'.format(opt, val)])
-        # need a database name to connect
-        cmd.append(self._database)
-        return self.cancellable.call(cmd, communicate_input=command)
-
-    def cleanup_archive_status(self):
-        status_dir = os.path.join(self._data_dir, 'pg_' + self.wal_name, 'archive_status')
-        try:
-            for f in os.listdir(status_dir):
-                path = os.path.join(status_dir, f)
-                try:
-                    if os.path.islink(path):
-                        os.unlink(path)
-                    elif os.path.isfile(path):
-                        os.remove(path)
-                except OSError:
-                    logger.exception('Unable to remove %s', path)
-        except OSError:
-            logger.exception('Unable to list %s', status_dir)
-
-    def fix_cluster_state(self):
-        self.cleanup_archive_status()
-
-        # Start in a single user mode and stop to produce a clean shutdown
-        opts = self.read_postmaster_opts()
-        opts.update({'archive_mode': 'on', 'archive_command': 'false'})
-        self.config.remove_recovery_conf()
-        return self.single_user_mode(options=opts) == 0 or None
 
     def schedule_sanity_checks_after_pause(self):
         """

patroni/postgresql/bootstrap.py

@@ -5,9 +5,8 @@ import tempfile
 import time
 
 from patroni.dcs import RemoteMember
-from patroni.utils import deep_compare, uri
+from patroni.utils import deep_compare
 from six import string_types
-from six.moves.urllib.parse import quote_plus
 
 logger = logging.getLogger(__name__)
 
@@ -99,7 +98,8 @@ class Bootstrap(object):
 
     def _custom_bootstrap(self, config):
         self._postgresql.set_state('running custom bootstrap script')
-        params = ['--scope=' + self._postgresql.scope, '--datadir=' + self._postgresql.data_dir]
+        params = [] if config.get('no_params') else ['--scope=' + self._postgresql.scope,
+                                                     '--datadir=' + self._postgresql.data_dir]
         try:
             logger.info('Running custom bootstrap script: %s', config['command'])
             if self._postgresql.cancellable.call(shlex.split(config['command']) + params) != 0:
@@ -123,28 +123,15 @@ class Bootstrap(object):
         cmd = config.get('post_bootstrap') or config.get('post_init')
         if cmd:
             r = self._postgresql.config.local_connect_kwargs
-
+            connstring = self._postgresql.config.format_dsn(r, True)
-            if 'host' in r:
+            if 'host' not in r:
-                # '/tmp' => '%2Ftmp' for unix socket path
-                host = quote_plus(r['host']) if r['host'].startswith('/') else r['host']
-            else:
-                host = ''
-
                 # https://www.postgresql.org/docs/current/static/libpq-pgpass.html
                 # A host name of localhost matches both TCP (host name localhost) and Unix domain socket
                 # (pghost empty or the default socket directory) connections coming from the local machine.
                 r['host'] = 'localhost'  # set it to localhost to write into pgpass
 
-            if 'user' in r:
+            env = self._postgresql.config.write_pgpass(r) if 'password' in r else None
-                user = r['user']
+            env['PGOPTIONS'] = '-c synchronous_commit=local'
-            else:
-                user = ''
-                if 'password' in r:
-                    import getpass
-                    r.setdefault('user', os.environ.get('PGUSER', getpass.getuser()))
-
-            connstring = uri('postgres', (host, r['port']), r['database'], user)
-            env = self._postgresql.write_pgpass(r) if 'password' in r else None
 
             try:
                 ret = self._postgresql.cancellable.call(shlex.split(cmd) + [connstring], env=env)
@@ -176,9 +163,9 @@ class Bootstrap(object):
 
         if clone_member and clone_member.conn_url:
             r = clone_member.conn_kwargs(self._postgresql.config.replication)
-            connstring = uri('postgres', (r['host'], r['port']), r['database'], r['user'])
             # add the credentials to connect to the replica origin to pgpass.
-            env = self._postgresql.write_pgpass(r)
+            env = self._postgresql.config.write_pgpass(r)
+            connstring = self._postgresql.config.format_dsn(r, True)
         else:
             connstring = ''
             env = os.environ.copy()
@@ -325,7 +312,15 @@ BEGIN
         CREATE ROLE "{0}" WITH {1};
     END IF;
 END;$$""".format(name, ' '.join(options))
+        self._postgresql.query('SET log_statement TO none')
+        self._postgresql.query('SET log_min_duration_statement TO -1')
+        self._postgresql.query("SET log_min_error_statement TO 'log'")
+        try:
             self._postgresql.query(sql, *params)
+        finally:
+            self._postgresql.query('RESET log_min_error_statement')
+            self._postgresql.query('RESET log_min_duration_statement')
+            self._postgresql.query('RESET log_statement')
 
     def post_bootstrap(self, config, task):
         try:
@@ -361,6 +356,7 @@ END;$$""".format(f, rewind['username'])
                     self._running_custom_bootstrap = False
                     # If we don't have custom configuration for pg_hba.conf we need to restore original file
                     if not postgresql.config.get('pg_hba'):
+                        if os.path.exists(postgresql.config.pg_hba_conf):
                             os.unlink(postgresql.config.pg_hba_conf)
                         postgresql.config.restore_configuration_files()
                     postgresql.config.write_postgresql_conf()
@@ -369,7 +365,7 @@ END;$$""".format(f, rewind['username'])
                     # at this point there should be no recovery.conf
                     postgresql.config.remove_recovery_conf()
 
-                    if postgresql.config.hba_file and postgresql.config.hba_file != postgresql.config.pg_hba_conf:
+                    if postgresql.config.hba_file:
                         postgresql.restart()
                     else:
                         postgresql.config.replace_pg_hba()

patroni/postgresql/callback_executor.py

@@ -1,40 +1,36 @@
 import logging
-import subprocess
+
-from threading import Event, Lock, Thread
+from patroni.postgresql.cancellable import CancellableExecutor
+from threading import Condition, Thread
 
 logger = logging.getLogger(__name__)
 
 
-class CallbackExecutor(Thread):
+class CallbackExecutor(CancellableExecutor, Thread):
 
     def __init__(self):
-        super(CallbackExecutor, self).__init__()
+        CancellableExecutor.__init__(self)
+        Thread.__init__(self)
         self.daemon = True
-        self._lock = Lock()
         self._cmd = None
-        self._process = None
+        self._condition = Condition()
-        self._callback_event = Event()
         self.start()
 
     def call(self, cmd):
-        with self._lock:
+        self._kill_process()
-            if self._process and self._process.poll() is None:
+        with self._condition:
-                try:
-                    self._process.kill()
-                    logger.warning('Killed the old callback process because it was still running: %s', self._cmd)
-                except OSError:
-                    logger.exception('Failed to kill the old callback')
             self._cmd = cmd
-        self._callback_event.set()
+            self._condition.notify()
 
     def run(self):
         while True:
-            self._callback_event.wait()
+            with self._condition:
-            self._callback_event.clear()
+                if self._cmd is None:
+                    self._condition.wait()
+                cmd, self._cmd = self._cmd, None
+
             with self._lock:
-                try:
+                if not self._start_process(cmd, close_fds=True):
-                    self._process = subprocess.Popen(self._cmd, close_fds=True)
-                except Exception:
-                    logger.exception('Failed to execute %s',  self._cmd)
                     continue
             self._process.wait()
+            self._kill_children()

patroni/postgresql/cancellable.py

@@ -1,36 +1,92 @@
 import logging
-import os
+import psutil
 import subprocess
 
 from patroni.exceptions import PostgresException
 from patroni.utils import polling_loop
-from six import string_types
 from threading import Lock
 
 logger = logging.getLogger(__name__)
 
 
-class CancellableSubprocess(object):
+class CancellableExecutor(object):
+
+    """
+    There must be only one such process so that AsyncExecutor can easily cancel it.
+    """
 
     def __init__(self):
-        self._is_cancelled = False
         self._process = None
+        self._process_cmd = None
+        self._process_children = []
         self._lock = Lock()
 
+    def _start_process(self, cmd, *args, **kwargs):
+        """This method must be executed only when the `_lock` is acquired"""
+
+        try:
+            self._process_children = []
+            self._process_cmd = cmd
+            self._process = psutil.Popen(cmd, *args, **kwargs)
+        except Exception:
+            return logger.exception('Failed to execute %s',  cmd)
+        return True
+
+    def _kill_process(self):
+        with self._lock:
+            if self._process is not None and self._process.is_running() and not self._process_children:
+                try:
+                    self._process.suspend()  # Suspend the process before getting list of childrens
+                except psutil.Error as e:
+                    logger.info('Failed to suspend the process: %s', e.msg)
+
+                try:
+                    self._process_children = self._process.children(recursive=True)
+                except psutil.Error:
+                    pass
+
+                try:
+                    self._process.kill()
+                    logger.warning('Killed %s because it was still running', self._process_cmd)
+                except psutil.NoSuchProcess:
+                    pass
+                except psutil.AccessDenied as e:
+                    logger.warning('Failed to kill the process: %s', e.msg)
+
+    def _kill_children(self):
+        waitlist = []
+        with self._lock:
+            for child in self._process_children:
+                try:
+                    child.kill()
+                except psutil.NoSuchProcess:
+                    continue
+                except psutil.AccessDenied as e:
+                    logger.info('Failed to kill child process: %s', e.msg)
+                waitlist.append(child)
+        psutil.wait_procs(waitlist)
+
+
+class CancellableSubprocess(CancellableExecutor):
+
+    def __init__(self):
+        super(CancellableSubprocess, self).__init__()
+        self._is_cancelled = False
+
     def call(self, *args, **kwargs):
         for s in ('stdin', 'stdout', 'stderr'):
             kwargs.pop(s, None)
 
-        communicate_input = 'communicate_input' in kwargs
+        communicate = kwargs.pop('communicate', None)
-        if communicate_input:
+        if isinstance(communicate, dict):
-            input_data = kwargs.pop('communicate_input', None)
+            input_data = communicate.get('input')
-            if not isinstance(input_data, string_types):
+            if input_data:
-                input_data = ''
+                if input_data[-1] != '\n':
-            if input_data and input_data[-1] != '\n':
                     input_data += '\n'
+                input_data = input_data.encode('utf-8')
             kwargs['stdin'] = subprocess.PIPE
-            kwargs['stdout'] = open(os.devnull, 'w')
+            kwargs['stdout'] = subprocess.PIPE
-            kwargs['stderr'] = subprocess.STDOUT
+            kwargs['stderr'] = subprocess.PIPE
 
         try:
             with self._lock:
@@ -38,17 +94,16 @@ class CancellableSubprocess(object):
                     raise PostgresException('cancelled')
 
                 self._is_cancelled = False
-                self._process = subprocess.Popen(*args, **kwargs)
+                started = self._start_process(*args, **kwargs)
-
-            if communicate_input:
-                if input_data:
-                    self._process.communicate(input_data)
-                self._process.stdin.close()
 
+            if started:
+                if isinstance(communicate, dict):
+                    communicate['stdout'], communicate['stderr'] = self._process.communicate(input_data)
                 return self._process.wait()
         finally:
             with self._lock:
                 self._process = None
+            self._kill_children()
 
     def reset_is_cancelled(self):
         with self._lock:
@@ -62,15 +117,15 @@ class CancellableSubprocess(object):
     def cancel(self):
         with self._lock:
             self._is_cancelled = True
-            if self._process is None or self._process.returncode is not None:
+            if self._process is None or not self._process.is_running():
                 return
+
+            logger.info('Terminating %s', self._process_cmd)
             self._process.terminate()
 
         for _ in polling_loop(10):
             with self._lock:
-                if self._process is None or self._process.returncode is not None:
+                if self._process is None or not self._process.is_running():
                     return
 
-        with self._lock:
+        self._kill_process()
-            if self._process is not None and self._process.returncode is None:
-                self._process.kill()

patroni/postgresql/config.py

@@ -4,11 +4,16 @@ import re
 import shutil
 import socket
 import stat
+import time
 
-from requests.structures import CaseInsensitiveDict
 from six.moves.urllib_parse import urlparse, parse_qsl, unquote
 
-from ..utils import compare_values, parse_bool, parse_int, split_host_port, uri
+from .validator import CaseInsensitiveDict, recovery_parameters,\
+        transform_postgresql_parameter_value, transform_recovery_parameter_value
+from ..dcs import slot_name_from_member_name, RemoteMember
+from ..exceptions import PatroniFatalException
+from ..utils import compare_values, parse_bool, parse_int, split_host_port, uri, \
+        validate_directory, is_subpath
 
 logger = logging.getLogger(__name__)
 
@@ -57,14 +62,15 @@ def conninfo_uri_parse(dsn):
     return ret
 
 
-def read_param_value(value, is_quoted=False):
+def read_param_value(value):
     length = len(value)
     ret = ''
-    i = 0
+    is_quoted = value[0] == "'"
+    i = int(is_quoted)
     while i < length:
         if is_quoted:
             if value[i] == "'":
-                return ret, i
+                return ret, i + 1
         elif value[i].isspace():
             break
         if value[i] == '\\':
@@ -95,12 +101,10 @@ def conninfo_parse(dsn):
         if i >= length:
             return
 
-        is_quoted = dsn[i] == "'"
+        value, end = read_param_value(dsn[i:])
-        i += int(is_quoted)
-        value, end = read_param_value(dsn[i:], is_quoted)
         if value is None:
             return
-        i += end + int(is_quoted)
+        i += end
         ret[param] = value
     return ret
 
@@ -110,17 +114,17 @@ def parse_dsn(value):
     Very simple equivalent of `psycopg2.extensions.parse_dsn` introduced in 2.7.0.
     We are not using psycopg2 function in order to remain compatible with 2.5.4+.
     There is one minor difference though, this function removes `dbname` from the result
-    and sets the sslmode` to `prefer` if it is not present in the connection string.
+    and sets the `sslmode`, 'gssencmode', and `channel_binding` to `prefer` if it is not present in
-    This is necessary to simplify comparison of the old and the new values.
+    the connection string. This is necessary to simplify comparison of the old and the new values.
 
     >>> r = parse_dsn('postgresql://u%2Fse:pass@:%2f123,[%2Fhost2]/db%2Fsdf?application_name=mya%2Fpp&ssl=true')
     >>> r == {'application_name': 'mya/pp', 'host': ',/host2', 'sslmode': 'require',\
-              'password': 'pass', 'port': '/123', 'user': 'u/se'}
+              'password': 'pass', 'port': '/123', 'user': 'u/se', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
-    >>> r = parse_dsn(" host = 'host' dbname = db\\ name requiressl=1 ")
+    >>> r = parse_dsn(" host = 'host' dbname = db\\\\ name requiressl=1 ")
-    >>> r == {'host': 'host', 'sslmode': 'require'}
+    >>> r == {'host': 'host', 'sslmode': 'require', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
-    >>> parse_dsn('requiressl = 0\\\\') == {'sslmode': 'prefer'}
+    >>> parse_dsn('requiressl = 0\\\\') == {'sslmode': 'prefer', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
     >>> parse_dsn("host=a foo = '") is None
     True
@@ -144,9 +148,75 @@ def parse_dsn(value):
             ret.setdefault('sslmode', 'prefer')
         if 'dbname' in ret:
             del ret['dbname']
+        ret.setdefault('gssencmode', 'prefer')
+        ret.setdefault('channel_binding', 'prefer')
     return ret
 
 
+def strip_comment(value):
+    i = value.find('#')
+    if i > -1:
+        value = value[:i].strip()
+    return value
+
+
+def read_recovery_param_value(value):
+    """
+    >>> read_recovery_param_value('') is None
+    True
+    >>> read_recovery_param_value("'") is None
+    True
+    >>> read_recovery_param_value("''a") is None
+    True
+    >>> read_recovery_param_value('a b') is None
+    True
+    >>> read_recovery_param_value("'''") is None
+    True
+    >>> read_recovery_param_value("'\\\\") is None
+    True
+    >>> read_recovery_param_value("'a' s#") is None
+    True
+    >>> read_recovery_param_value("'\\\\'''' #a")
+    "''"
+    >>> read_recovery_param_value('asd')
+    'asd'
+    """
+    value = value.strip()
+    length = len(value)
+    if length == 0:
+        return None
+    elif value[0] == "'":
+        if length == 1:
+            return None
+        ret = ''
+        i = 1
+        while i < length:
+            if value[i] == '\\':
+                i += 1
+                if i >= length:
+                    return None
+            elif value[i] == "'":
+                i += 1
+                if i >= length:
+                    break
+                if value[i] in ('#', ' '):
+                    if strip_comment(value[i:]):
+                        return None
+                    break
+                if value[i] != "'":
+                    return None
+            ret += value[i]
+            i += 1
+        else:
+            return None
+        return ret
+    else:
+        value = strip_comment(value)
+        if not value or ' ' in value or '\\' in value:
+            return None
+    return value
+
+
 def mtime(filename):
     try:
         return os.stat(filename).st_mtime
@@ -154,6 +224,37 @@ def mtime(filename):
         return None
 
 
+class ConfigWriter(object):
+
+    def __init__(self, filename):
+        self._filename = filename
+        self._fd = None
+
+    def __enter__(self):
+        self._fd = open(self._filename, 'w')
+        self.writeline('# Do not edit this file manually!\n# It will be overwritten by Patroni!')
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        if self._fd:
+            self._fd.close()
+
+    def writeline(self, line):
+        self._fd.write(line)
+        self._fd.write('\n')
+
+    def writelines(self, lines):
+        for line in lines:
+            self.writeline(line)
+
+    @staticmethod
+    def escape(value):  # Escape (by doubling) any single quotes or backslashes in given string
+        return re.sub(r'([\'\\])', r'\1\1', str(value))
+
+    def write_param(self, param, value):
+        self.writeline("{0} = '{1}'".format(param, self.escape(value)))
+
+
 class ConfigHandler(object):
 
     # List of parameters which must be always passed to postmaster as command line options
@@ -179,6 +280,7 @@ class ConfigHandler(object):
         'max_connections': (100, lambda v: int(v) >= 25, 90100),
         'max_wal_senders': (10, lambda v: int(v) >= 3, 90100),
         'wal_keep_segments': (8, lambda v: int(v) >= 1, 90100),
+        'wal_keep_size': ('128MB', lambda v: parse_int(v, 'MB') >= 16, 130000),
         'max_prepared_transactions': (0, lambda v: int(v) >= 0, 90100),
         'max_locks_per_transaction': (64, lambda v: int(v) >= 32, 90100),
         'track_commit_timestamp': ('off', lambda v: parse_bool(v) is not None, 90500),
@@ -187,26 +289,7 @@ class ConfigHandler(object):
         'wal_log_hints': ('on', lambda _: False, 90400)
     })
 
-    _RECOVERY_PARAMETERS = {
+    _RECOVERY_PARAMETERS = set(recovery_parameters.keys())
-        'archive_cleanup_command',
-        'restore_command',
-        'recovery_end_command',
-        'recovery_target',
-        'recovery_target_name',
-        'recovery_target_time',
-        'recovery_target_xid',
-        'recovery_target_lsn',
-        'recovery_target_inclusive',
-        'recovery_target_timeline',
-        'recovery_target_action',
-        'recovery_min_apply_delay',
-        'primary_conninfo',
-        'primary_slot_name',
-        'promote_trigger_file',
-        'trigger_file'
-    }
-
-    _CONFIG_WARNING_HEADER = '# Do not edit this file manually!\n# It will be overwritten by Patroni!\n'
 
     def __init__(self, postgresql, config):
         self._postgresql = postgresql
@@ -224,9 +307,15 @@ class ConfigHandler(object):
         self._standby_signal = os.path.join(postgresql.data_dir, 'standby.signal')
         self._auto_conf = os.path.join(postgresql.data_dir, 'postgresql.auto.conf')
         self._auto_conf_mtime = None
+        self._pgpass = os.path.abspath(config.get('pgpass') or os.path.join(os.path.expanduser('~'), 'pgpass'))
+        if os.path.exists(self._pgpass) and not os.path.isfile(self._pgpass):
+            raise PatroniFatalException("'{0}' exists and it's not a file, check your `postgresql.pgpass` configuration"
+                                        .format(self._pgpass))
+        self._passfile = None
+        self._passfile_mtime = None
         self._synchronous_standby_names = None
         self._postmaster_ctime = None
-        self._primary_conninfo = None
+        self._current_recovery_params = None
         self._config = {}
         self._recovery_params = {}
         self.reload_config(config)
@@ -235,6 +324,21 @@ class ConfigHandler(object):
         self._server_parameters = self.get_server_parameters(self._config)
         self._adjust_recovery_parameters()
 
+    def try_to_create_dir(self, d, msg):
+        d = os.path.join(self._postgresql._data_dir, d)
+        if (not is_subpath(self._postgresql._data_dir, d) or not self._postgresql.data_directory_empty()):
+            validate_directory(d, msg)
+
+    def check_directories(self):
+        if "unix_socket_directories" in self._server_parameters:
+            for d in self._server_parameters["unix_socket_directories"].split(","):
+                self.try_to_create_dir(d.strip(), "'{}' is defined in unix_socket_directories, {}")
+        if "stats_temp_directory" in self._server_parameters:
+            self.try_to_create_dir(self._server_parameters["stats_temp_directory"],
+                                   "'{}' is defined in stats_temp_directory, {}")
+        self.try_to_create_dir(os.path.dirname(self._pgpass),
+                               "'{}' is defined in `postgresql.pgpass`, {}")
+
     @property
     def _configuration_to_save(self):
         configuration = [os.path.basename(self._postgresql_conf)]
@@ -242,7 +346,7 @@ class ConfigHandler(object):
             configuration.append(os.path.basename(self._postgresql_base_conf_name))
         if not self.hba_file:
             configuration.append('pg_hba.conf')
-        if not self._server_parameters.get('ident_file'):
+        if not self.ident_file:
             configuration.append('pg_ident.conf')
         return configuration
 
@@ -283,28 +387,27 @@ class ConfigHandler(object):
         if 'custom_conf' not in self._config and not os.path.exists(self._postgresql_base_conf):
             os.rename(self._postgresql_conf, self._postgresql_base_conf)
 
-        with open(self._postgresql_conf, 'w') as f:
+        with ConfigWriter(self._postgresql_conf) as f:
-            os.chmod(self._postgresql_conf, stat.S_IWRITE | stat.S_IREAD)
+            include = self._config.get('custom_conf') or self._postgresql_base_conf_name
-            f.write(self._CONFIG_WARNING_HEADER)
+            f.writeline("include '{0}'\n".format(ConfigWriter.escape(include)))
-            f.write("include '{0}'\n\n".format(self._config.get('custom_conf') or self._postgresql_base_conf_name))
             for name, value in sorted((configuration or self._server_parameters).items()):
+                value = transform_postgresql_parameter_value(self._postgresql.major_version, name, value)
                 if (not self._postgresql.bootstrap.running_custom_bootstrap or name != 'hba_file') \
-                        and name not in self._RECOVERY_PARAMETERS:
+                        and name not in self._RECOVERY_PARAMETERS and value is not None:
-                    f.write("{0} = '{1}'\n".format(name, value))
+                    f.write_param(name, value)
             # when we are doing custom bootstrap we assume that we don't know superuser password
             # and in order to be able to change it, we are opening trust access from a certain address
             # therefore we need to make sure that hba_file is not overriden
             # after changing superuser password we will "revert" all these "changes"
             if self._postgresql.bootstrap.running_custom_bootstrap or 'hba_file' not in self._server_parameters:
-                f.write("hba_file = '{0}'\n".format(self._pg_hba_conf.replace('\\', '\\\\')))
+                f.write_param('hba_file', self._pg_hba_conf)
             if 'ident_file' not in self._server_parameters:
-                f.write("ident_file = '{0}'\n".format(self._pg_ident_conf.replace('\\', '\\\\')))
+                f.write_param('ident_file', self._pg_ident_conf)
 
             if self._postgresql.major_version >= 120000:
                 if self._recovery_params:
-                    f.write('\n# recovery.conf\n')
+                    f.writeline('\n# recovery.conf')
-                    for name, value in sorted(self._recovery_params.items()):
+                    self._write_recovery_params(f, self._recovery_params)
-                        f.write("{0} = '{1}'\n".format(name, value))
 
                 if not self._postgresql.bootstrap.keep_existing_recovery_conf:
                     self._sanitize_auto_conf()
@@ -326,24 +429,21 @@ class ConfigHandler(object):
         # when we are doing custom bootstrap we assume that we don't know superuser password
         # and in order to be able to change it, we are opening trust access from a certain address
         if self._postgresql.bootstrap.running_custom_bootstrap:
-            addresses = {'': 'local'}
+            addresses = {} if os.name == 'nt' else {'': 'local'}  # windows doesn't yet support unix-domain sockets
             if 'host' in self.local_replication_address and not self.local_replication_address['host'].startswith('/'):
                 addresses.update({sa[0] + '/32': 'host' for _, _, _, _, sa in socket.getaddrinfo(
                                   self.local_replication_address['host'], self.local_replication_address['port'],
                                   0, socket.SOCK_STREAM, socket.IPPROTO_TCP)})
 
-            with open(self._pg_hba_conf, 'w') as f:
+            with ConfigWriter(self._pg_hba_conf) as f:
-                f.write(self._CONFIG_WARNING_HEADER)
                 for address, t in addresses.items():
-                    f.write((
+                    f.writeline((
                         '{0}\treplication\t{1}\t{3}\ttrust\n'
-                        '{0}\tall\t{2}\t{3}\ttrust\n'
+                        '{0}\tall\t{2}\t{3}\ttrust'
                     ).format(t, self.replication['username'], self._superuser.get('username') or 'all', address))
         elif not self.hba_file and self._config.get('pg_hba'):
-            with open(self._pg_hba_conf, 'w') as f:
+            with ConfigWriter(self._pg_hba_conf) as f:
-                f.write(self._CONFIG_WARNING_HEADER)
+                f.writelines(self._config['pg_hba'])
-                for line in self._config['pg_hba']:
-                    f.write('{0}\n'.format(line))
             return True
 
     def replace_pg_ident(self):
@@ -354,123 +454,302 @@ class ConfigHandler(object):
         :returns: True if pg_ident.conf was rewritten.
         """
 
-        if not self._server_parameters.get('ident_file') and self._config.get('pg_ident'):
+        if not self.ident_file and self._config.get('pg_ident'):
-            with open(self._pg_ident_conf, 'w') as f:
+            with ConfigWriter(self._pg_ident_conf) as f:
-                f.write(self._CONFIG_WARNING_HEADER)
+                f.writelines(self._config['pg_ident'])
-                for line in self._config['pg_ident']:
-                    f.write('{0}\n'.format(line))
             return True
 
     def primary_conninfo_params(self, member):
-        name = self._postgresql.name
+        if not (member and member.conn_url) or member.name == self._postgresql.name:
-        if not (member and member.conn_url) or member.name == name:
             return None
         ret = member.conn_kwargs(self.replication)
-        ret.update(application_name=name, sslmode='prefer')
+        ret['application_name'] = self._postgresql.name
+        ret.setdefault('sslmode', 'prefer')
+        if self._postgresql.major_version >= 120000:
+            ret.setdefault('gssencmode', 'prefer')
+        if self._postgresql.major_version >= 130000:
+            ret.setdefault('channel_binding', 'prefer')
         if self._krbsrvname:
             ret['krbsrvname'] = self._krbsrvname
         if 'database' in ret:
             del ret['database']
         return ret
 
-    def primary_conninfo(self, member):
+    def format_dsn(self, params, include_dbname=False):
-        r = self.primary_conninfo_params(member)
+        # A list of keywords that can be found in a conninfo string. Follows what is acceptable by libpq
-        if not r:
+        keywords = ('dbname', 'user', 'passfile' if params.get('passfile') else 'password', 'host', 'port',
-            return None
+                    'sslmode', 'sslcompression', 'sslcert', 'sslkey', 'sslrootcert', 'sslcrl',
-        keywords = 'user password host port sslmode application_name krbsrvname'.split()
+                    'application_name', 'krbsrvname', 'gssencmode', 'channel_binding')
-        return ' '.join('{0}={{{0}}}'.format(kw) for kw in keywords if r.get(kw)).format(**r)
+        if include_dbname:
+            params = params.copy()
+            params['dbname'] = params.get('database') or self._postgresql.database
+            # we are abusing information about the necessity of dbname
+            # dsn should contain passfile or password only if there is no dbname in it (it is used in recovery.conf)
+            skip = {'passfile', 'password'}
+        else:
+            skip = {'dbname'}
+
+        def escape(value):
+            return re.sub(r'([\'\\ ])', r'\\\1', str(value))
+
+        return ' '.join('{0}={1}'.format(kw, escape(params[kw])) for kw in keywords
+                        if kw not in skip and params.get(kw) is not None)
+
+    def _write_recovery_params(self, fd, recovery_params):
+        if self._postgresql.major_version >= 90500:
+            pause_at_recovery_target = parse_bool(recovery_params.pop('pause_at_recovery_target', None))
+            if pause_at_recovery_target is not None:
+                recovery_params.setdefault('recovery_target_action', 'pause' if pause_at_recovery_target else 'promote')
+        else:
+            if str(recovery_params.pop('recovery_target_action', None)).lower() == 'promote':
+                recovery_params.setdefault('pause_at_recovery_target', 'false')
+        for name, value in sorted(recovery_params.items()):
+            if name == 'primary_conninfo':
+                if 'password' in value and self._postgresql.major_version >= 100000:
+                    self.write_pgpass(value)
+                    value['passfile'] = self._passfile = self._pgpass
+                    self._passfile_mtime = mtime(self._pgpass)
+                value = self.format_dsn(value)
+            else:
+                value = transform_recovery_parameter_value(self._postgresql.major_version, name, value)
+                if value is None:
+                    continue
+            fd.write_param(name, value)
+
+    def build_recovery_params(self, member):
+        recovery_params = CaseInsensitiveDict({p: v for p, v in self.get('recovery_conf', {}).items()
+                                               if not p.lower().startswith('recovery_target') and
+                                               p.lower() not in ('primary_conninfo', 'primary_slot_name')})
+        recovery_params.update({'standby_mode': 'on', 'recovery_target_timeline': 'latest'})
+        if self._postgresql.major_version >= 120000:
+            # on pg12 we want to protect from following params being set in one of included files
+            # not doing so might result in a standby being paused, promoted or shutted down.
+            recovery_params.update({'recovery_target': '', 'recovery_target_name': '', 'recovery_target_time': '',
+                                    'recovery_target_xid': '', 'recovery_target_lsn': ''})
+
+        is_remote_master = isinstance(member, RemoteMember)
+        primary_conninfo = self.primary_conninfo_params(member)
+        if primary_conninfo:
+            use_slots = self.get('use_slots', True) and self._postgresql.major_version >= 90400
+            if use_slots and not (is_remote_master and member.no_replication_slot):
+                primary_slot_name = member.primary_slot_name if is_remote_master else self._postgresql.name
+                recovery_params['primary_slot_name'] = slot_name_from_member_name(primary_slot_name)
+            recovery_params['primary_conninfo'] = primary_conninfo
+
+        # standby_cluster config might have different parameters, we want to override them
+        standby_cluster_params = ['restore_command', 'archive_cleanup_command']\
+            + (['recovery_min_apply_delay'] if is_remote_master else [])
+        recovery_params.update({p: member.data.get(p) for p in standby_cluster_params if member and member.data.get(p)})
+        return recovery_params
 
     def recovery_conf_exists(self):
         if self._postgresql.major_version >= 120000:
             return os.path.exists(self._standby_signal) or os.path.exists(self._recovery_signal)
         return os.path.exists(self._recovery_conf)
 
-    def _read_primary_conninfo(self):
+    @property
+    def _triggerfile_good_name(self):
+        return 'trigger_file' if self._postgresql.major_version < 120000 else 'promote_trigger_file'
+
+    @property
+    def _triggerfile_wrong_name(self):
+        return 'trigger_file' if self._postgresql.major_version >= 120000 else 'promote_trigger_file'
+
+    @property
+    def _recovery_parameters_to_compare(self):
+        skip_params = {'pause_at_recovery_target', 'recovery_target_inclusive',
+                       'recovery_target_action', 'standby_mode', self._triggerfile_wrong_name}
+        return self._RECOVERY_PARAMETERS - skip_params
+
+    def _read_recovery_params(self):
         pg_conf_mtime = mtime(self._postgresql_conf)
         auto_conf_mtime = mtime(self._auto_conf)
+        passfile_mtime = mtime(self._passfile) if self._passfile else False
         postmaster_ctime = self._postgresql.is_running()
         if postmaster_ctime:
             postmaster_ctime = postmaster_ctime.create_time()
 
         if self._postgresql_conf_mtime == pg_conf_mtime and self._auto_conf_mtime == auto_conf_mtime \
-                and self._postmaster_ctime == postmaster_ctime:
+                and self._passfile_mtime == passfile_mtime and self._postmaster_ctime == postmaster_ctime:
             return None, False
 
         try:
-            primary_conninfo = self._postgresql.query('SHOW primary_conninfo').fetchone()[0]
+            values = self._get_pg_settings(self._recovery_parameters_to_compare).values()
+            values = {p[0]: [p[1], p[4] == 'postmaster', p[5]] for p in values}
             self._postgresql_conf_mtime = pg_conf_mtime
             self._auto_conf_mtime = auto_conf_mtime
             self._postmaster_ctime = postmaster_ctime
         except Exception:
-            primary_conninfo = None
+            values = None
-        return primary_conninfo, True
+        return values, True
 
-    def _read_primary_conninfo_pre_v12(self):
+    def _read_recovery_params_pre_v12(self):
         recovery_conf_mtime = mtime(self._recovery_conf)
-        if recovery_conf_mtime == self._recovery_conf_mtime:
+        passfile_mtime = mtime(self._passfile) if self._passfile else False
+        if recovery_conf_mtime == self._recovery_conf_mtime and passfile_mtime == self._passfile_mtime:
             return None, False
 
-        primary_conninfo = ''
+        values = {}
         with open(self._recovery_conf, 'r') as f:
             for line in f:
+                line = line.strip()
+                if not line or line.startswith('#'):
+                    continue
+                value = None
                 match = PARAMETER_RE.match(line)
-                if match and match.group(1) == 'primary_conninfo':
+                if match:
-                    i = match.end()
+                    value = read_recovery_param_value(line[match.end():])
-                    if i < len(line):
+                if value is None:
-                        is_quoted = line[i] == "'"
+                    return None, True
-                        i += int(is_quoted)
+                values[match.group(1)] = [value, True]
-                        primary_conninfo, _ = read_param_value(line[i:], is_quoted)
             self._recovery_conf_mtime = recovery_conf_mtime
-        return primary_conninfo, True
+        values.setdefault('recovery_min_apply_delay', ['0', True])
+        values['recovery_min_apply_delay'][0] = parse_int(values['recovery_min_apply_delay'][0], 'ms')
+        values.update({param: ['', True] for param in self._recovery_parameters_to_compare if param not in values})
+        return values, True
 
-    def check_recovery_conf(self, member):  # Name is confusing. In fact it checks the value of primary_conninfo
+    def _check_passfile(self, passfile, wanted_primary_conninfo):
-        # TODO: recovery.conf could be stale, would be nice to detect that.
+        # If there is a passfile in the primary_conninfo try to figure out that
-        if self._postgresql.major_version >= 120000:
+        # the passfile contains the line allowing connection to the given node.
-            if not os.path.exists(self._standby_signal):
+        # We assume that the passfile was created by Patroni and therefore doing
+        # the full match and not covering cases when host, port or user are set to '*'
+        passfile_mtime = mtime(passfile)
+        if passfile_mtime:
+            try:
+                with open(passfile) as f:
+                    wanted_line = self._pgpass_line(wanted_primary_conninfo).strip()
+                    for raw_line in f:
+                        if raw_line.strip() == wanted_line:
+                            self._passfile = passfile
+                            self._passfile_mtime = passfile_mtime
+                            return True
+            except Exception:
+                logger.info('Failed to read %s', passfile)
         return False
 
-            _read_primary_conninfo = self._read_primary_conninfo
+    def _check_primary_conninfo(self, primary_conninfo, wanted_primary_conninfo):
-        else:
-            if not self.recovery_conf_exists():
-                return False
-
-            _read_primary_conninfo = self._read_primary_conninfo_pre_v12
-
-        primary_conninfo, updated = _read_primary_conninfo()
-        # updated indicates that mtime of postgresql.conf, postgresql.auto.conf, or recovery.conf was changed
-        # and the primary_conninfo value was read either from config or from the database connection.
-        if updated:
-            # primary_conninfo is one of:
-            # - None (exception or unparsable config)
-            # - '' (not in config)
-            # - or the actual dsn value
-            self._primary_conninfo = primary_conninfo
-            if primary_conninfo:
-                # We will cache parsed value until the next config change.
-                self._primary_conninfo = parse_dsn(primary_conninfo)
-                # If we failed to parse non-empty connection string this indicates that config if broken.
-                if not self._primary_conninfo:
-                    return False
-            elif primary_conninfo is not None:
-                self._primary_conninfo = {}
-            else:  # primary_conninfo is None, config is probably broken
-                return False
-
-        wanted_primary_conninfo = self.primary_conninfo_params(member)
         # first we will cover corner cases, when we are replicating from somewhere while shouldn't
         # or there is no primary_conninfo but we should replicate from some specific node.
         if not wanted_primary_conninfo:
-            return not self._primary_conninfo
+            return not primary_conninfo
-        elif not self._primary_conninfo:
+        elif not primary_conninfo:
             return False
 
-        return all(self._primary_conninfo.get(p) == str(v) for p, v in wanted_primary_conninfo.items())
+        wal_receiver_primary_conninfo = self._postgresql.primary_conninfo()
+        if wal_receiver_primary_conninfo:
+            wal_receiver_primary_conninfo = parse_dsn(wal_receiver_primary_conninfo)
+            # when wal receiver is alive use primary_conninfo from pg_stat_wal_receiver for comparison
+            if wal_receiver_primary_conninfo:
+                primary_conninfo = wal_receiver_primary_conninfo
+                # There could be no password in the primary_conninfo or it is masked.
+                # Just copy the "desired" value in order to make comparison succeed.
+                if 'password' in wanted_primary_conninfo:
+                    primary_conninfo['password'] = wanted_primary_conninfo['password']
+
+        if 'passfile' in primary_conninfo and 'password' not in primary_conninfo \
+                and 'password' in wanted_primary_conninfo:
+            if self._check_passfile(primary_conninfo['passfile'], wanted_primary_conninfo):
+                primary_conninfo['password'] = wanted_primary_conninfo['password']
+            else:
+                return False
+
+        return all(primary_conninfo.get(p) == str(v) for p, v in wanted_primary_conninfo.items() if v is not None)
+
+    def check_recovery_conf(self, member):
+        """Returns a tuple. The first boolean element indicates that recovery params don't match
+           and the second is set to `True` if the restart is required in order to apply new values"""
+
+        # TODO: recovery.conf could be stale, would be nice to detect that.
+        if self._postgresql.major_version >= 120000:
+            if not os.path.exists(self._standby_signal):
+                return True, True
+
+            _read_recovery_params = self._read_recovery_params
+        else:
+            if not self.recovery_conf_exists():
+                return True, True
+
+            _read_recovery_params = self._read_recovery_params_pre_v12
+
+        params, updated = _read_recovery_params()
+        # updated indicates that mtime of postgresql.conf, postgresql.auto.conf, or recovery.conf
+        # was changed and params were read either from the config or from the database connection.
+        if updated:
+            if params is None:  # exception or unparsable config
+                return True, True
+
+            # We will cache parsed value until the next config change.
+            self._current_recovery_params = params
+            primary_conninfo = params['primary_conninfo']
+            if primary_conninfo[0]:
+                primary_conninfo[0] = parse_dsn(params['primary_conninfo'][0])
+                # If we failed to parse non-empty connection string this indicates that config if broken.
+                if not primary_conninfo[0]:
+                    return True, True
+            else:  # empty string, primary_conninfo is not in the config
+                primary_conninfo[0] = {}
+
+        # when wal receiver is alive take primary_slot_name from pg_stat_wal_receiver
+        wal_receiver_primary_slot_name = self._postgresql.primary_slot_name()
+        if not wal_receiver_primary_slot_name and self._postgresql.primary_conninfo():
+            wal_receiver_primary_slot_name = ''
+        if wal_receiver_primary_slot_name is not None:
+            self._current_recovery_params['primary_slot_name'][0] = wal_receiver_primary_slot_name
+
+        required = {'restart': 0, 'reload': 0}
+
+        def record_missmatch(mtype):
+            required['restart' if mtype else 'reload'] += 1
+
+        wanted_recovery_params = self.build_recovery_params(member)
+        for param, value in self._current_recovery_params.items():
+            # Skip certain parameters defined in the included postgres config files
+            # if we know that they are not specified in the patroni configuration.
+            if len(value) > 2 and value[2] not in (self._postgresql_conf, self._auto_conf) and \
+                    param in ('archive_cleanup_command', 'promote_trigger_file', 'recovery_end_command',
+                              'recovery_min_apply_delay', 'restore_command') and param not in wanted_recovery_params:
+                continue
+            if param == 'recovery_min_apply_delay':
+                if not compare_values('integer', 'ms', value[0], wanted_recovery_params.get(param, 0)):
+                    record_missmatch(value[1])
+            elif param == 'standby_mode':
+                if not compare_values('bool', None, value[0], wanted_recovery_params.get(param, 'on')):
+                    record_missmatch(value[1])
+            elif param == 'primary_conninfo':
+                if not self._check_primary_conninfo(value[0], wanted_recovery_params.get('primary_conninfo', {})):
+                    record_missmatch(value[1])
+            elif (param != 'primary_slot_name' or wanted_recovery_params.get('primary_conninfo')) \
+                    and str(value[0]) != str(wanted_recovery_params.get(param, '')):
+                record_missmatch(value[1])
+        return required['restart'] + required['reload'] > 0, required['restart'] > 0
 
     @staticmethod
     def _remove_file_if_exists(name):
         if os.path.isfile(name) or os.path.islink(name):
             os.unlink(name)
 
+    @staticmethod
+    def _pgpass_line(record):
+        if 'password' in record:
+            def escape(value):
+                return re.sub(r'([:\\])', r'\\\1', str(value))
+
+            record = {n: escape(record.get(n) or '*') for n in ('host', 'port', 'user', 'password')}
+            return '{host}:{port}:*:{user}:{password}'.format(**record)
+
+    def write_pgpass(self, record):
+        line = self._pgpass_line(record)
+        if not line:
+            return os.environ.copy()
+
+        with open(self._pgpass, 'w') as f:
+            os.chmod(self._pgpass, stat.S_IWRITE | stat.S_IREAD)
+            f.write(line)
+
+        env = os.environ.copy()
+        env['PGPASSFILE'] = self._pgpass
+        return env
+
     def write_recovery_conf(self, recovery_params):
         if self._postgresql.major_version >= 120000:
             if parse_bool(recovery_params.pop('standby_mode', None)):
@@ -480,10 +759,9 @@ class ConfigHandler(object):
                 open(self._recovery_signal, 'w').close()
             self._recovery_params = recovery_params
         else:
-            with open(self._recovery_conf, 'w') as f:
+            with ConfigWriter(self._recovery_conf) as f:
                 os.chmod(self._recovery_conf, stat.S_IWRITE | stat.S_IREAD)
-                for name, value in recovery_params.items():
+                self._write_recovery_params(f, recovery_params)
-                    f.write("{0} = '{1}'\n".format(name, value))
 
     def remove_recovery_conf(self):
         for name in (self._recovery_conf, self._standby_signal, self._recovery_signal):
@@ -522,13 +800,9 @@ class ConfigHandler(object):
             self._config['recovery_conf'] = recovery_conf
 
         if self.get('recovery_conf'):
-            good_name, bad_name = 'trigger_file', 'promote_trigger_file'
+            value = self._config['recovery_conf'].pop(self._triggerfile_wrong_name, None)
-            if self._postgresql.major_version >= 120000:
+            if self._triggerfile_good_name not in self._config['recovery_conf'] and value:
-                good_name, bad_name = bad_name, good_name
+                self._config['recovery_conf'][self._triggerfile_good_name] = value
-
-            value = self._config['recovery_conf'].pop(bad_name, None)
-            if good_name not in self._config['recovery_conf'] and value:
-                self._config['recovery_conf'][good_name] = value
 
     def get_server_parameters(self, config):
         parameters = config['parameters'].copy()
@@ -542,8 +816,20 @@ class ConfigHandler(object):
                     parameters.pop('synchronous_standby_names', None)
             else:
                 parameters['synchronous_standby_names'] = self._synchronous_standby_names
-        if self._postgresql.major_version >= 90600 and parameters['wal_level'] == 'hot_standby':
+
-            parameters['wal_level'] = 'replica'
+        # Handle hot_standby <-> replica rename
+        if parameters.get('wal_level') == ('hot_standby' if self._postgresql.major_version >= 90600 else 'replica'):
+            parameters['wal_level'] = 'replica' if self._postgresql.major_version >= 90600 else 'hot_standby'
+
+        # Try to recalcualte wal_keep_segments <-> wal_keep_size assuming that typical wal_segment_size is 16MB.
+        # The real segment size could be estimated from pg_control, but we don't really care, because the only goal of
+        # this exercise is improving cross version compatibility and user must set the correct parameter in the config.
+        if self._postgresql.major_version >= 130000:
+            wal_keep_segments = parameters.pop('wal_keep_segments', self.CMDLINE_OPTIONS['wal_keep_segments'][0])
+            parameters.setdefault('wal_keep_size', str(wal_keep_segments * 16) + 'MB')
+        elif self._postgresql.major_version:
+            wal_keep_size = parse_int(parameters.pop('wal_keep_size', self.CMDLINE_OPTIONS['wal_keep_size'][0]), 'MB')
+            parameters.setdefault('wal_keep_segments', int((wal_keep_size + 8) / 16))
         ret = CaseInsensitiveDict({k: v for k, v in parameters.items() if not self._postgresql.major_version or
                                    self._postgresql.major_version >= self.CMDLINE_OPTIONS.get(k, (0, 1, 90100))[2]})
         ret.update({k: os.path.join(self._config_dir, ret[k]) for k in ('hba_file', 'ident_file') if k in ret})
@@ -568,14 +854,18 @@ class ConfigHandler(object):
     @property
     def local_connect_kwargs(self):
         ret = self._local_address.copy()
+        # add all of the other connection settings that are available
+        ret.update(self._superuser)
+        # if the "username" parameter is present, it actually needs to be "user"
+        # for connecting to PostgreSQL
+        if 'username' in self._superuser:
+            ret['user'] = self._superuser['username']
+            del ret['username']
+        # ensure certain Patroni configurations are available
         ret.update({'database': self._postgresql.database,
                     'fallback_application_name': 'Patroni',
                     'connect_timeout': 3,
                     'options': '-c statement_timeout=2000'})
-        if 'username' in self._superuser:
-            ret['user'] = self._superuser['username']
-        if 'password' in self._superuser:
-            ret['password'] = self._superuser['password']
         return ret
 
     def resolve_connection_addresses(self):
@@ -602,63 +892,87 @@ class ConfigHandler(object):
 
         self._postgresql.set_connection_kwargs(self.local_connect_kwargs)
 
-    def reload_config(self, config):
+    def _get_pg_settings(self, names):
+        return {r[0]: r for r in self._postgresql.query(('SELECT name, setting, unit, vartype, context, sourcefile'
+                                                         + ' FROM pg_catalog.pg_settings ' +
+                                                         ' WHERE pg_catalog.lower(name) = ANY(%s)'),
+                                                        [n.lower() for n in names])}
+
+    @staticmethod
+    def _handle_wal_buffers(old_values, changes):
+        wal_block_size = parse_int(old_values['wal_block_size'][1])
+        wal_segment_size = old_values['wal_segment_size']
+        wal_segment_unit = parse_int(wal_segment_size[2], 'B') if wal_segment_size[2][0].isdigit() else 1
+        wal_segment_size = parse_int(wal_segment_size[1]) * wal_segment_unit / wal_block_size
+        default_wal_buffers = min(max(parse_int(old_values['shared_buffers'][1]) / 32, 8), wal_segment_size)
+
+        wal_buffers = old_values['wal_buffers']
+        new_value = str(changes['wal_buffers'] or -1)
+
+        new_value = default_wal_buffers if new_value == '-1' else parse_int(new_value, wal_buffers[2])
+        old_value = default_wal_buffers if wal_buffers[1] == '-1' else parse_int(*wal_buffers[1:3])
+
+        if new_value == old_value:
+            del changes['wal_buffers']
+
+    def reload_config(self, config, sighup=False):
         self._superuser = config['authentication'].get('superuser', {})
         server_parameters = self.get_server_parameters(config)
 
         conf_changed = hba_changed = ident_changed = local_connection_address_changed = pending_restart = False
         if self._postgresql.state == 'running':
-            changes = CaseInsensitiveDict({p: v for p, v in server_parameters.items() if '.' not in p})
+            changes = CaseInsensitiveDict({p: v for p, v in server_parameters.items()
-            changes.update({p: None for p in self._server_parameters.keys() if not ('.' in p or p in changes)})
+                                           if p.lower() not in self._RECOVERY_PARAMETERS})
+            changes.update({p: None for p in self._server_parameters.keys()
+                            if not (p in changes or p.lower() in self._RECOVERY_PARAMETERS)})
             if changes:
+                if 'wal_buffers' in changes:  # we need to calculate the default value of wal_buffers
+                    undef = [p for p in ('shared_buffers', 'wal_segment_size', 'wal_block_size') if p not in changes]
+                    changes.update({p: None for p in undef})
                 # XXX: query can raise an exception
-                for r in self._postgresql.query(('SELECT name, setting, unit, vartype, context '
+                old_values = self._get_pg_settings(changes.keys())
-                                                 + 'FROM pg_catalog.pg_settings ' +
+                if 'wal_buffers' in changes:
-                                                 ' WHERE pg_catalog.lower(name) IN ('
+                    self._handle_wal_buffers(old_values, changes)
-                                                 + ', '.join(['%s'] * len(changes)) +
+                    for p in undef:
-                                                 ')'), *(k.lower() for k in changes.keys())):
+                        del changes[p]
+
+                for r in old_values.values():
                     if r[4] != 'internal' and r[0] in changes:
                         new_value = changes.pop(r[0])
                         if new_value is None or not compare_values(r[3], r[2], r[1], new_value):
+                            conf_changed = True
                             if r[4] == 'postmaster':
                                 pending_restart = True
-                                logger.info('Changed %s from %s to %s (restart required)', r[0], r[1], new_value)
+                                logger.info('Changed %s from %s to %s (restart might be required)',
+                                            r[0], r[1], new_value)
                                 if config.get('use_unix_socket') and r[0] == 'unix_socket_directories'\
                                         or r[0] in ('listen_addresses', 'port'):
                                     local_connection_address_changed = True
                             else:
                                 logger.info('Changed %s from %s to %s', r[0], r[1], new_value)
+                for param, value in changes.items():
+                    if '.' in param:
+                        # Check that user-defined-paramters have changed (parameters with period in name)
+                        if value is None or param not in self._server_parameters \
+                                or str(value) != str(self._server_parameters[param]):
+                            logger.info('Changed %s from %s to %s', param, self._server_parameters.get(param), value)
                             conf_changed = True
-                for param in changes:
+                    elif param in server_parameters:
-                    if param in server_parameters:
                         logger.warning('Removing invalid parameter `%s` from postgresql.parameters', param)
                         server_parameters.pop(param)
 
-            # Check that user-defined-paramters have changed (parameters with period in name)
+            if (not server_parameters.get('hba_file') or server_parameters['hba_file'] == self._pg_hba_conf) \
-            if not conf_changed:
+                    and config.get('pg_hba'):
-                for p, v in server_parameters.items():
-                    if '.' in p and (p not in self._server_parameters or str(v) != str(self._server_parameters[p])):
-                        logger.info('Changed %s from %s to %s', p, self._server_parameters.get(p), v)
-                        conf_changed = True
-                        break
-                if not conf_changed:
-                    for p, v in self._server_parameters.items():
-                        if '.' in p and (p not in server_parameters or str(v) != str(server_parameters[p])):
-                            logger.info('Changed %s from %s to %s', p, v, server_parameters.get(p))
-                            conf_changed = True
-                            break
-
-            if not server_parameters.get('hba_file') and config.get('pg_hba'):
                 hba_changed = self._config.get('pg_hba', []) != config['pg_hba']
 
-            if not server_parameters.get('ident_file') and config.get('pg_ident'):
+            if (not server_parameters.get('ident_file') or server_parameters['ident_file'] == self._pg_hba_conf) \
+                    and config.get('pg_ident'):
                 ident_changed = self._config.get('pg_ident', []) != config['pg_ident']
 
         self._config = config
         self._postgresql.set_pending_restart(pending_restart)
         self._server_parameters = server_parameters
         self._adjust_recovery_parameters()
-        self._connect_address = config.get('connect_address')
         self._krbsrvname = config.get('krbsrvname')
 
         # for not so obvious connection attempts that may happen outside of pyscopg2
@@ -677,22 +991,34 @@ class ConfigHandler(object):
         if ident_changed:
             self.replace_pg_ident()
 
-        if conf_changed or hba_changed or ident_changed:
+        if sighup or conf_changed or hba_changed or ident_changed:
-            logger.info('PostgreSQL configuration items changed, reloading configuration.')
+            logger.info('Reloading PostgreSQL configuration.')
             self._postgresql.reload()
-        elif not pending_restart:
+            if self._postgresql.major_version >= 90500:
+                time.sleep(1)
+                try:
+                    pending_restart = self._postgresql.query('SELECT COUNT(*) FROM pg_catalog.pg_settings'
+                                                             ' WHERE pending_restart').fetchone()[0] > 0
+                    self._postgresql.set_pending_restart(pending_restart)
+                except Exception as e:
+                    logger.warning('Exception %r when running query', e)
+        else:
             logger.info('No PostgreSQL configuration items changed, nothing to reload.')
 
-    def set_synchronous_standby(self, name):
+    def set_synchronous_standby(self, sync_members):
         """Sets a node to be synchronous standby and if changed does a reload for PostgreSQL."""
-        if name and name != '*':
+        if sync_members and sync_members != ['*']:
-            name = quote_ident(name)
+            sync_members = [quote_ident(x) for x in sync_members]
-        if name != self._synchronous_standby_names:
+        if self._postgresql.major_version >= 90600 and len(sync_members) > 1:
-            if name is None:
+            sync_param = '{0} ({1})'.format(len(sync_members), ','.join(sync_members))
+        else:
+            sync_param = next(iter(sync_members), None)
+        if sync_param != self._synchronous_standby_names:
+            if sync_param is None:
                 self._server_parameters.pop('synchronous_standby_names', None)
             else:
-                self._server_parameters['synchronous_standby_names'] = name
+                self._server_parameters['synchronous_standby_names'] = sync_param
-            self._synchronous_standby_names = name
+            self._synchronous_standby_names = sync_param
             if self._postgresql.state == 'running':
                 self.write_postgresql_conf()
                 self._postgresql.reload()
@@ -728,6 +1054,10 @@ class ConfigHandler(object):
 
         for name, cname in options_mapping.items():
             value = parse_int(effective_configuration[name])
+            if cname not in data:
+                logger.warning('%s is missing from pg_controldata output', cname)
+                continue
+
             cvalue = parse_int(data[cname])
             if cvalue > value:
                 effective_configuration[name] = cvalue
@@ -747,9 +1077,15 @@ class ConfigHandler(object):
         return self._config['authentication'].get('rewind', self._superuser) \
                 if self._postgresql.major_version >= 110000 else self._superuser
 
+    @property
+    def ident_file(self):
+        ident_file = self._server_parameters.get('ident_file')
+        return None if ident_file == self._pg_ident_conf else ident_file
+
     @property
     def hba_file(self):
-        return self._server_parameters.get('hba_file')
+        hba_file = self._server_parameters.get('hba_file')
+        return None if hba_file == self._pg_hba_conf else hba_file
 
     @property
     def pg_hba_conf(self):

patroni/postgresql/postmaster.py

@@ -5,13 +5,24 @@ import psutil
 import re
 import signal
 import subprocess
+import sys
+
+from patroni import PATRONI_ENV_PREFIX, KUBERNETES_ENV_PREFIX
+
+# avoid spawning the resource tracker process
+if sys.version_info >= (3, 8):  # pragma: no cover
+    import multiprocessing.resource_tracker
+    multiprocessing.resource_tracker.getfd = lambda: 0
+elif sys.version_info >= (3, 4):  # pragma: no cover
+    import multiprocessing.semaphore_tracker
+    multiprocessing.semaphore_tracker.getfd = lambda: 0
 
 logger = logging.getLogger(__name__)
 
 STOP_SIGNALS = {
-    'smart': signal.SIGTERM,
+    'smart': 'TERM',
-    'fast': signal.SIGINT,
+    'fast': 'INT',
-    'immediate': signal.SIGQUIT if os.name != 'nt' else signal.SIGABRT,
+    'immediate': 'QUIT',
 }
 
 
@@ -94,7 +105,43 @@ class PostmasterProcess(psutil.Process):
         except psutil.NoSuchProcess:
             return None
 
-    def signal_stop(self, mode):
+    def signal_kill(self):
+        """to suspend and kill postmaster and all children
+
+        :returns True if postmaster and children are killed, False if error
+        """
+        try:
+            self.suspend()
+        except psutil.NoSuchProcess:
+            return True
+        except psutil.Error as e:
+            logger.warning('Failed to suspend postmaster: %s', e)
+
+        try:
+            children = self.children(recursive=True)
+        except psutil.NoSuchProcess:
+            return True
+        except psutil.Error as e:
+            logger.warning('Failed to get a list of postmaster children: %s', e)
+            children = []
+
+        try:
+            self.kill()
+        except psutil.NoSuchProcess:
+            return True
+        except psutil.Error as e:
+            logger.warning('Could not kill postmaster: %s', e)
+            return False
+
+        for child in children:
+            try:
+                child.kill()
+            except psutil.Error:
+                pass
+        psutil.wait_procs(children + [self])
+        return True
+
+    def signal_stop(self, mode, pg_ctl='pg_ctl'):
         """Signal postmaster process to stop
 
         :returns None if signaled, True if process is already gone, False if error
@@ -102,8 +149,10 @@ class PostmasterProcess(psutil.Process):
         if self.is_single_user:
             logger.warning("Cannot stop server; single-user server is running (PID: {0})".format(self.pid))
             return False
+        if os.name != 'posix':
+            return self.pg_ctl_kill(mode, pg_ctl)
         try:
-            self.send_signal(STOP_SIGNALS[mode])
+            self.send_signal(getattr(signal, 'SIG' + STOP_SIGNALS[mode]))
         except psutil.NoSuchProcess:
             return True
         except psutil.AccessDenied as e:
@@ -112,6 +161,16 @@ class PostmasterProcess(psutil.Process):
 
         return None
 
+    def pg_ctl_kill(self, mode, pg_ctl):
+        try:
+            status = subprocess.call([pg_ctl, "kill", STOP_SIGNALS[mode], str(self.pid)])
+        except OSError:
+            return False
+        if status == 0:
+            return None
+        else:
+            return not self.is_running()
+
     def wait_for_user_backends_to_close(self):
         # These regexps are cross checked against versions PostgreSQL 9.1 .. 11
         aux_proc_re = re.compile("(?:postgres:)( .*:)? (?:(?:archiver|startup|autovacuum launcher|autovacuum worker|"
@@ -153,7 +212,8 @@ class PostmasterProcess(psutil.Process):
         # In order to make everything portable we can't use fork&exec approach here, so  we will call
         # ourselves and pass list of arguments which must be used to start postgres.
         # On Windows, in order to run a side-by-side assembly the specified env must include a valid SYSTEMROOT.
-        env = {p: os.environ[p] for p in ('PATH', 'LD_LIBRARY_PATH', 'LC_ALL', 'LANG', 'SYSTEMROOT') if p in os.environ}
+        env = {p: os.environ[p] for p in os.environ if not p.startswith(
+            PATRONI_ENV_PREFIX) and not p.startswith(KUBERNETES_ENV_PREFIX)}
         try:
             proc = PostmasterProcess._from_pidfile(data_dir)
             if proc and not proc._is_postmaster_process():
@@ -170,8 +230,9 @@ class PostmasterProcess(psutil.Process):
             pass
         cmdline = [pgcommand, '-D', data_dir, '--config-file={}'.format(conf)] + options
         logger.debug("Starting postgres: %s", " ".join(cmdline))
-        parent_conn, child_conn = multiprocessing.Pipe(False)
+        ctx = multiprocessing.get_context('spawn') if sys.version_info >= (3, 4) else multiprocessing
-        proc = multiprocessing.Process(target=pg_ctl_start, args=(child_conn, cmdline, env))
+        parent_conn, child_conn = ctx.Pipe(False)
+        proc = ctx.Process(target=pg_ctl_start, args=(child_conn, cmdline, env))
         proc.start()
         pid = parent_conn.recv()
         proc.join()

patroni/postgresql/rewind.py

@@ -1,10 +1,14 @@
 import logging
 import os
+import six
 import subprocess
 
-from patroni.dcs import Leader
+from threading import Lock, Thread
-from patroni.postgresql.connection import get_connection_cursor
+
-from patroni.postgresql.misc import parse_history, parse_lsn
+from .connection import get_connection_cursor
+from .misc import parse_history, parse_lsn
+from ..async_executor import CriticalTask
+from ..dcs import Leader
 
 logger = logging.getLogger(__name__)
 
@@ -12,10 +16,16 @@ REWIND_STATUS = type('Enum', (), {'INITIAL': 0, 'CHECKPOINT': 1, 'CHECK': 2, 'NE
                                   'NOT_NEED': 4, 'SUCCESS': 5, 'FAILED': 6})
 
 
+def format_lsn(lsn, full=False):
+    template = '{0:X}/{1:08X}' if full else '{0:X}/{1:X}'
+    return template.format(lsn >> 32, lsn & 0xFFFFFFFF)
+
+
 class Rewind(object):
 
     def __init__(self, postgresql):
         self._postgresql = postgresql
+        self._checkpoint_task_lock = Lock()
         self.reset_state()
 
     @staticmethod
@@ -60,32 +70,102 @@ class Rewind(object):
         except Exception:
             return logger.exception('Exception when working with leader')
 
+    def _get_checkpoint_end(self, timeline, lsn):
+        """The checkpoint record size in WAL depends on postgres major version and platform (memory alignment).
+        Hence, the only reliable way to figure out where it ends, read the record from file with the help of pg_waldump
+        and parse the output. We are trying to read two records, and expect that it wil fail to read the second one:
+        `pg_waldump: fatal: error in WAL record at 0/182E220: invalid record length at 0/182E298: wanted 24, got 0`
+        The error message contains information about LSN of the next record, which is exactly where checkpoint ends."""
+
+        cmd = self._postgresql.pgcommand('pg_{0}dump'.format(self._postgresql.wal_name))
+        lsn8 = format_lsn(lsn, True)
+        lsn = format_lsn(lsn)
+        env = os.environ.copy()
+        env.update(LANG='C', LC_ALL='C', PGDATA=self._postgresql.data_dir)
+        try:
+            waldump = subprocess.Popen([cmd, '-t', str(timeline), '-s', lsn, '-n', '2'],
+                                       stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env)
+            out, err = waldump.communicate()
+            waldump.wait()
+        except Exception as e:
+            logger.error('Failed to execute `%s -t %s -s %s -n 2`: %r', cmd, timeline, lsn, e)
+        else:
+            out = out.decode('utf-8').rstrip().split('\n')
+            err = err.decode('utf-8').rstrip().split('\n')
+            pattern = 'error in WAL record at {0}: invalid record length at '.format(lsn)
+
+            if len(out) == 1 and len(err) == 1 and ', lsn: {0}, prev '.format(lsn8) in out[0] and pattern in err[0]:
+                i = err[0].find(pattern) + len(pattern)
+                j = err[0].find(": wanted ", i)
+                if j > -1:
+                    try:
+                        return parse_lsn(err[0][i:j])
+                    except Exception as e:
+                        logger.error('Failed to parse lsn %s: %r', err[0][i:j], e)
+            logger.error('Failed to parse `%s -t %s -s %s -n 2` output', cmd, timeline, lsn)
+            logger.error(' stdout=%s', '\n'.join(out))
+            logger.error(' stderr=%s', '\n'.join(err))
+
+        return 0
+
     def _get_local_timeline_lsn_from_controldata(self):
-        timeline = lsn = None
+        in_recovery = timeline = lsn = None
         data = self._postgresql.controldata()
         try:
             if data.get('Database cluster state') == 'shut down in recovery':
+                in_recovery = True
                 lsn = data.get('Minimum recovery ending location')
                 timeline = int(data.get("Min recovery ending loc's timeline"))
                 if lsn == '0/0' or timeline == 0:  # it was a master when it crashed
                     data['Database cluster state'] = 'shut down'
             if data.get('Database cluster state') == 'shut down':
+                in_recovery = False
                 lsn = data.get('Latest checkpoint location')
                 timeline = int(data.get("Latest checkpoint's TimeLineID"))
         except (TypeError, ValueError):
             logger.exception('Failed to get local timeline and lsn from pg_controldata output')
-        return timeline, lsn
+
+        if lsn is not None:
+            try:
+                lsn = parse_lsn(lsn)
+            except (IndexError, ValueError) as e:
+                logger.error('Exception when parsing lsn %s: %r', lsn, e)
+                lsn = None
+
+        return in_recovery, timeline, lsn
 
     def _get_local_timeline_lsn(self):
-        if self._postgresql.is_running():  # if postgres is running - get timeline and lsn from replication connection
+        if self._postgresql.is_running():  # if postgres is running - get timeline from replication connection
-            timeline, lsn = self._postgresql.get_local_timeline_lsn_from_replication_connection()
+            in_recovery = True
+            timeline = self._postgresql.received_timeline() or self._postgresql.get_replica_timeline()
+            lsn = self._postgresql.replayed_location()
         else:  # otherwise analyze pg_controldata output
-            timeline, lsn = self._get_local_timeline_lsn_from_controldata()
+            in_recovery, timeline, lsn = self._get_local_timeline_lsn_from_controldata()
-        logger.info('Local timeline=%s lsn=%s', timeline, lsn)
+
-        return timeline, lsn
+        log_lsn = format_lsn(lsn) if isinstance(lsn, six.integer_types) else lsn
+        logger.info('Local timeline=%s lsn=%s', timeline, log_lsn)
+        return in_recovery, timeline, lsn
+
+    @staticmethod
+    def _log_master_history(history, i):
+        start = max(0, i - 3)
+        end = None if i + 4 >= len(history) else i + 2
+        history_show = []
+
+        def format_history_line(line):
+            return '{0}\t{1}\t{2}'.format(line[0], format_lsn(line[1]), line[2])
+
+        for line in history[start:end]:
+            history_show.append(format_history_line(line))
+
+        if line != history[-1]:
+            history_show.append('...')
+            history_show.append(format_history_line(history[-1]))
+
+        logger.info('master: history=%s', '\n'.join(history_show))
 
     def _check_timeline_and_lsn(self, leader):
-        local_timeline, local_lsn = self._get_local_timeline_lsn()
+        in_recovery, local_timeline, local_lsn = self._get_local_timeline_lsn()
         if local_timeline is None or local_lsn is None:
             return
 
@@ -104,25 +184,32 @@ class Rewind(object):
                 logger.info('master_timeline=%s', master_timeline)
                 if local_timeline > master_timeline:  # Not always supported by pg_rewind
                     need_rewind = True
+                elif local_timeline == master_timeline:
+                    need_rewind = False
                 elif master_timeline > 1:
                     cur.execute('TIMELINE_HISTORY %s', (master_timeline,))
                     history = bytes(cur.fetchone()[1]).decode('utf-8')
-                    logger.info('master: history=%s', history)
+                    logger.debug('master: history=%s', history)
-                else:  # local_timeline == master_timeline == 1
-                    need_rewind = False
         except Exception:
             return logger.exception('Exception when working with master via replication connection')
 
         if history is not None:
-            for parent_timeline, switchpoint, _ in parse_history(history):
+            history = list(parse_history(history))
+            for i, (parent_timeline, switchpoint, _) in enumerate(history):
                 if parent_timeline == local_timeline:
-                    try:
+                    # We don't need to rewind when:
-                        need_rewind = parse_lsn(local_lsn) >= switchpoint
+                    # 1. for replica: replayed location is not ahead of switchpoint
-                    except (IndexError, ValueError):
+                    # 2. for the former primary: end of checkpoint record is the same as switchpoint
-                        logger.exception('Exception when parsing lsn')
+                    if in_recovery:
+                        need_rewind = local_lsn > switchpoint
+                    elif local_lsn >= switchpoint:
+                        need_rewind = True
+                    else:
+                        need_rewind = switchpoint != self._get_checkpoint_end(local_timeline, local_lsn)
                     break
                 elif parent_timeline > local_timeline:
                     break
+            self._log_master_history(history, i)
 
         self._state = need_rewind and REWIND_STATUS.NEED or REWIND_STATUS.NOT_NEED
 
@@ -131,36 +218,113 @@ class Rewind(object):
             self._check_timeline_and_lsn(leader)
         return leader and leader.conn_url and self._state == REWIND_STATUS.NEED
 
-    def check_for_checkpoint_after_promote(self):
+    def __checkpoint(self, task, wakeup):
-        if self._state == REWIND_STATUS.INITIAL and self._postgresql.is_leader():
         try:
-                timeline = int(self._postgresql.controldata().get("Latest checkpoint's TimeLineID"))
+            result = self._postgresql.checkpoint()
-                if self._postgresql.get_master_timeline() == timeline:
+        except Exception as e:
+            result = 'Exception: ' + str(e)
+        with task:
+            task.complete(not bool(result))
+            if task.result:
+                wakeup()
+
+    def ensure_checkpoint_after_promote(self, wakeup):
+        """After promote issue a CHECKPOINT from a new thread and asynchronously check the result.
+        In case if CHECKPOINT failed, just check that timeline in pg_control was updated."""
+
+        if self._state == REWIND_STATUS.INITIAL and self._postgresql.is_leader():
+            with self._checkpoint_task_lock:
+                if self._checkpoint_task:
+                    with self._checkpoint_task:
+                        if self._checkpoint_task.result:
+                            self._state = REWIND_STATUS.CHECKPOINT
+                        if self._checkpoint_task.result is not False:
+                            return
+                else:
+                    self._checkpoint_task = CriticalTask()
+                    return Thread(target=self.__checkpoint, args=(self._checkpoint_task, wakeup)).start()
+
+            if self._postgresql.get_master_timeline() == self._postgresql.pg_control_timeline():
                 self._state = REWIND_STATUS.CHECKPOINT
-            except (TypeError, ValueError):
-                logger.exception('Failed to parse timeline from pg_controldata output')
 
     def checkpoint_after_promote(self):
         return self._state == REWIND_STATUS.CHECKPOINT
 
+    def _fetch_missing_wal(self, restore_command, wal_filename):
+        cmd = ''
+        length = len(restore_command)
+        i = 0
+        while i < length:
+            if restore_command[i] == '%' and i + 1 < length:
+                i += 1
+                if restore_command[i] == 'p':
+                    cmd += os.path.join(self._postgresql.wal_dir, wal_filename)
+                elif restore_command[i] == 'f':
+                    cmd += wal_filename
+                elif restore_command[i] == 'r':
+                    cmd += '000000010000000000000001'
+                elif restore_command[i] == '%':
+                    cmd += '%'
+                else:
+                    cmd += '%'
+                    i -= 1
+            else:
+                cmd += restore_command[i]
+            i += 1
+
+        logger.info('Trying to fetch the missing wal: %s', cmd)
+        return self._postgresql.cancellable.call(cmd, shell=True) == 0
+
+    def _find_missing_wal(self, data):
+        # could not open file "$PGDATA/pg_wal/0000000A00006AA100000068": No such file or directory
+        pattern = 'could not open file "'
+        for line in data.decode('utf-8').split('\n'):
+            b = line.find(pattern)
+            if b > -1:
+                b += len(pattern)
+                e = line.find('": ', b)
+                if e > -1 and '/' in line[b:e]:
+                    waldir, wal_filename = line[b:e].rsplit('/', 1)
+                    if waldir.endswith('/pg_' + self._postgresql.wal_name) and len(wal_filename) == 24:
+                        return wal_filename
+
     def pg_rewind(self, r):
         # prepare pg_rewind connection
-        env = self._postgresql.write_pgpass(r)
+        env = self._postgresql.config.write_pgpass(r)
-        env['PGOPTIONS'] = '-c statement_timeout=0'
+        env.update(LANG='C', LC_ALL='C', PGOPTIONS='-c statement_timeout=0')
-        dsn_attrs = [
+        dsn = self._postgresql.config.format_dsn(r, True)
-            ('user', r.get('user')),
-            ('host', r.get('host')),
-            ('port', r.get('port')),
-            ('dbname', r.get('database') or self._postgresql.database),
-            ('sslmode', 'prefer'),
-            ('sslcompression', '1'),
-        ]
-        dsn = " ".join("{0}={1}".format(k, v) for k, v in dsn_attrs if v is not None)
         logger.info('running pg_rewind from %s', dsn)
-        try:
+
-            return self._postgresql.cancellable.call([self._postgresql.pgcommand('pg_rewind'), '-D',
+        restore_command = self._postgresql.config.get('recovery_conf', {}).get('restore_command') \
-                                                      self._postgresql.data_dir, '--source-server', dsn], env=env) == 0
+            if self._postgresql.major_version < 120000 else self._postgresql.get_guc_value('restore_command')
-        except OSError:
+
+        cmd = [self._postgresql.pgcommand('pg_rewind')]
+        if self._postgresql.major_version >= 130000 and restore_command:
+            cmd.append('--restore-target-wal')
+        cmd.extend(['-D', self._postgresql.data_dir, '--source-server', dsn])
+
+        while True:
+            results = {}
+            ret = self._postgresql.cancellable.call(cmd, env=env, communicate=results)
+
+            logger.info('pg_rewind exit code=%s', ret)
+            if ret is None:
+                return False
+
+            logger.info(' stdout=%s', results['stdout'].decode('utf-8'))
+            logger.info(' stderr=%s', results['stderr'].decode('utf-8'))
+            if ret == 0:
+                return True
+
+            if not restore_command or self._postgresql.major_version >= 130000:
+                return False
+
+            missing_wal = self._find_missing_wal(results['stderr']) or self._find_missing_wal(results['stdout'])
+            if not missing_wal:
+                return False
+
+            if not self._fetch_missing_wal(restore_command, missing_wal):
+                logger.info('Failed to fetch WAL segment %s required for pg_rewind', missing_wal)
                 return False
 
     def execute(self, leader):
@@ -203,6 +367,8 @@ class Rewind(object):
 
     def reset_state(self):
         self._state = REWIND_STATUS.INITIAL
+        with self._checkpoint_task_lock:
+            self._checkpoint_task = None
 
     @property
     def is_needed(self):
@@ -215,3 +381,50 @@ class Rewind(object):
     @property
     def failed(self):
         return self._state == REWIND_STATUS.FAILED
+
+    def read_postmaster_opts(self):
+        """returns the list of option names/values from postgres.opts, Empty dict if read failed or no file"""
+        result = {}
+        try:
+            with open(os.path.join(self._postgresql.data_dir, 'postmaster.opts')) as f:
+                data = f.read()
+                for opt in data.split('" "'):
+                    if '=' in opt and opt.startswith('--'):
+                        name, val = opt.split('=', 1)
+                        result[name.strip('-')] = val.rstrip('"\n')
+        except IOError:
+            logger.exception('Error when reading postmaster.opts')
+        return result
+
+    def single_user_mode(self, communicate=None, options=None):
+        """run a given command in a single-user mode. If the command is empty - then just start and stop"""
+        cmd = [self._postgresql.pgcommand('postgres'), '--single', '-D', self._postgresql.data_dir]
+        for opt, val in sorted((options or {}).items()):
+            cmd.extend(['-c', '{0}={1}'.format(opt, val)])
+        # need a database name to connect
+        cmd.append('template1')
+        return self._postgresql.cancellable.call(cmd, communicate=communicate)
+
+    def cleanup_archive_status(self):
+        status_dir = os.path.join(self._postgresql.wal_dir, 'archive_status')
+        try:
+            for f in os.listdir(status_dir):
+                path = os.path.join(status_dir, f)
+                try:
+                    if os.path.islink(path):
+                        os.unlink(path)
+                    elif os.path.isfile(path):
+                        os.remove(path)
+                except OSError:
+                    logger.exception('Unable to remove %s', path)
+        except OSError:
+            logger.exception('Unable to list %s', status_dir)
+
+    def ensure_clean_shutdown(self):
+        self.cleanup_archive_status()
+
+        # Start in a single user mode and stop to produce a clean shutdown
+        opts = self.read_postmaster_opts()
+        opts.update({'archive_mode': 'on', 'archive_command': 'false'})
+        self._postgresql.config.remove_recovery_conf()
+        return self.single_user_mode(options=opts) == 0 or None

patroni/postgresql/slots.py

@@ -15,19 +15,14 @@ class SlotsHandler(object):
 
     def __init__(self, postgresql):
         self._postgresql = postgresql
-        self._use_slots = postgresql.config.get('use_slots', True)
         self._replication_slots = {}  # already existing replication slots
         self.schedule()
 
-    @property
-    def use_slots(self):
-        return self._use_slots and self._postgresql.major_version >= 90400
-
     def _query(self, sql, *params):
         return self._postgresql.query(sql, *params, retry=False)
 
     def load_replication_slots(self):
-        if self.use_slots and self._schedule_load_slots:
+        if self._postgresql.major_version >= 90400 and self._schedule_load_slots:
             replication_slots = {}
             cursor = self._query('SELECT slot_name, slot_type, plugin, database FROM pg_catalog.pg_replication_slots')
             for r in cursor:
@@ -45,7 +40,7 @@ class SlotsHandler(object):
         return cursor.rowcount == 1
 
     def sync_replication_slots(self, cluster):
-        if self.use_slots:
+        if self._postgresql.major_version >= 90400:
             try:
                 self.load_replication_slots()
 
@@ -104,5 +99,5 @@ class SlotsHandler(object):
 
     def schedule(self, value=None):
         if value is None:
-            value = self.use_slots
+            value = self._postgresql.major_version >= 90400
         self._schedule_load_slots = value

patroni/postgresql/validator.py

@@ -0,0 +1,518 @@
+import abc
+import logging
+import six
+
+from collections import namedtuple
+from urllib3.response import HTTPHeaderDict
+
+from ..utils import parse_bool, parse_int, parse_real
+
+logger = logging.getLogger(__name__)
+
+
+class CaseInsensitiveDict(HTTPHeaderDict):
+
+    def add(self, key, val):
+        self[key] = val
+
+    def __getitem__(self, key):
+        return self._container[key.lower()][1]
+
+    def __repr__(self):
+        return str(dict(self.items()))
+
+    def copy(self):
+        return CaseInsensitiveDict(self._container.values())
+
+
+class Bool(namedtuple('Bool', 'version_from,version_till')):
+
+    @staticmethod
+    def transform(name, value):
+        if parse_bool(value) is not None:
+            return value
+        logger.warning('Removing bool parameter=%s from the config due to the invalid value=%s', name, value)
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Number(namedtuple('Number', 'version_from,version_till,min_val,max_val,unit')):
+
+    @staticmethod
+    @abc.abstractmethod
+    def parse(value, unit):
+        """parse value"""
+
+    def transform(self, name, value):
+        num_value = self.parse(value, self.unit)
+        if num_value is not None:
+            if num_value < self.min_val:
+                logger.warning('Value=%s of parameter=%s is too low, increasing to %s%s',
+                               value, name, self.min_val, self.unit or '')
+                return self.min_val
+            if num_value > self.max_val:
+                logger.warning('Value=%s of parameter=%s is too big, decreasing to %s%s',
+                               value, name, self.max_val, self.unit or '')
+                return self.max_val
+            return value
+        logger.warning('Removing %s parameter=%s from the config due to the invalid value=%s',
+                       self.__class__.__name__.lower(), name, value)
+
+
+class Integer(Number):
+
+    @staticmethod
+    def parse(value, unit):
+        return parse_int(value, unit)
+
+
+class Real(Number):
+
+    @staticmethod
+    def parse(value, unit):
+        return parse_real(value, unit)
+
+
+class Enum(namedtuple('Enum', 'version_from,version_till,possible_values')):
+
+    def transform(self, name, value):
+        if str(value).lower() in self.possible_values:
+            return value
+        logger.warning('Removing enum parameter=%s from the config due to the invalid value=%s', name, value)
+
+
+class EnumBool(Enum):
+
+    def transform(self, name, value):
+        if parse_bool(value) is not None:
+            return value
+        return super(EnumBool, self).transform(name, value)
+
+
+class String(namedtuple('String', 'version_from,version_till')):
+
+    @staticmethod
+    def transform(name, value):
+        return value
+
+
+# Format:
+#  key - parameter name
+#  value - tuple or multiple tuples if something was changing in GUC across postgres versions
+parameters = CaseInsensitiveDict({
+    'allow_system_table_mods': Bool(90300, None),
+    'application_name': String(90300, None),
+    'archive_command': String(90300, None),
+    'archive_mode': (
+        Bool(90300, 90500),
+        EnumBool(90500, None, ('always',))
+    ),
+    'archive_timeout': Integer(90300, None, 0, 1073741823, 's'),
+    'array_nulls': Bool(90300, None),
+    'authentication_timeout': Integer(90300, None,  1, 600, 's'),
+    'autovacuum': Bool(90300, None),
+    'autovacuum_analyze_scale_factor': Real(90300, None, 0, 100, None),
+    'autovacuum_analyze_threshold': Integer(90300, None, 0, 2147483647, None),
+    'autovacuum_freeze_max_age': Integer(90300, None, 100000, 2000000000, None),
+    'autovacuum_max_workers': (
+        Integer(90300, 90600, 1, 8388607, None),
+        Integer(90600, None, 1, 262143, None)
+    ),
+    'autovacuum_multixact_freeze_max_age': Integer(90300, None, 10000, 2000000000, None),
+    'autovacuum_naptime': Integer(90300, None, 1, 2147483, 's'),
+    'autovacuum_vacuum_cost_delay': (
+        Integer(90300, 120000, -1, 100, 'ms'),
+        Real(120000, None, -1, 100, 'ms')
+    ),
+    'autovacuum_vacuum_cost_limit': Integer(90300, None, -1, 10000, None),
+    'autovacuum_vacuum_insert_scale_factor': Real(130000, None, 0, 100, None),
+    'autovacuum_vacuum_insert_threshold': Integer(130000, None, -1, 2147483647, None),
+    'autovacuum_vacuum_scale_factor': Real(90300, None, 0, 100, None),
+    'autovacuum_vacuum_threshold': Integer(90300, None, 0, 2147483647, None),
+    'autovacuum_work_mem': Integer(90400, None, -1, 2147483647, 'kB'),
+    'backend_flush_after': Integer(90600, None, 0, 256, '8kB'),
+    'backslash_quote': EnumBool(90300, None, ('safe_encoding',)),
+    'backtrace_functions': String(130000, None),
+    'bgwriter_delay': Integer(90300, None, 10, 10000, 'ms'),
+    'bgwriter_flush_after': Integer(90600, None, 0, 256, '8kB'),
+    'bgwriter_lru_maxpages': (
+        Integer(90300, 100000, 0, 1000, None),
+        Integer(100000, None, 0, 1073741823, None)
+    ),
+    'bgwriter_lru_multiplier': Real(90300, None, 0, 10, None),
+    'bonjour': Bool(90300, None),
+    'bonjour_name': String(90300, None),
+    'bytea_output': Enum(90300, None, ('escape', 'hex')),
+    'check_function_bodies': Bool(90300, None),
+    'checkpoint_completion_target': Real(90300, None, 0, 1, None),
+    'checkpoint_flush_after': Integer(90600, None, 0, 256, '8kB'),
+    'checkpoint_segments': Integer(90300, 90500, 1, 2147483647, None),
+    'checkpoint_timeout': (
+        Integer(90300, 90600, 30, 3600, 's'),
+        Integer(90600, None, 30, 86400, 's')
+    ),
+    'checkpoint_warning': Integer(90300, None, 0, 2147483647, 's'),
+    'client_encoding': String(90300, None),
+    'client_min_messages': Enum(90300, None, ('debug5', 'debug4', 'debug3', 'debug2',
+                                              'debug1', 'log', 'notice', 'warning', 'error')),
+    'cluster_name': String(90500, None),
+    'commit_delay': Integer(90300, None, 0, 100000, None),
+    'commit_siblings': Integer(90300, None, 0, 1000, None),
+    'config_file': String(90300, None),
+    'constraint_exclusion': EnumBool(90300, None, ('partition',)),
+    'cpu_index_tuple_cost': Real(90300, None, 0, 1.79769e+308, None),
+    'cpu_operator_cost': Real(90300, None, 0, 1.79769e+308, None),
+    'cpu_tuple_cost': Real(90300, None, 0, 1.79769e+308, None),
+    'cursor_tuple_fraction': Real(90300, None, 0, 1, None),
+    'data_directory': String(90300, None),
+    'data_sync_retry': Bool(90400, None),
+    'DateStyle': String(90300, None),
+    'db_user_namespace': Bool(90300, None),
+    'deadlock_timeout': Integer(90300, None, 1, 2147483647, 'ms'),
+    'debug_pretty_print': Bool(90300, None),
+    'debug_print_parse': Bool(90300, None),
+    'debug_print_plan': Bool(90300, None),
+    'debug_print_rewritten': Bool(90300, None),
+    'default_statistics_target': Integer(90300, None, 1, 10000, None),
+    'default_table_access_method': String(120000, None),
+    'default_tablespace': String(90300, None),
+    'default_text_search_config': String(90300, None),
+    'default_transaction_deferrable': Bool(90300, None),
+    'default_transaction_isolation': Enum(90300, None, ('serializable', 'repeatable read',
+                                                        'read committed', 'read uncommitted')),
+    'default_transaction_read_only': Bool(90300, None),
+    'default_with_oids': Bool(90300, 120000),
+    'dynamic_library_path': String(90300, None),
+    'dynamic_shared_memory_type': (
+        Enum(90400, 120000, ('posix', 'sysv', 'mmap', 'none')),
+        Enum(120000, None, ('posix', 'sysv', 'mmap'))
+    ),
+    'effective_cache_size': Integer(90300, None, 1, 2147483647, '8kB'),
+    'effective_io_concurrency': Integer(90300, None, 0, 1000, None),
+    'enable_bitmapscan': Bool(90300, None),
+    'enable_gathermerge': Bool(100000, None),
+    'enable_hashagg': Bool(90300, None),
+    'enable_hashjoin': Bool(90300, None),
+    'enable_incremental_sort': Bool(130000, None),
+    'enable_indexonlyscan': Bool(90300, None),
+    'enable_indexscan': Bool(90300, None),
+    'enable_material': Bool(90300, None),
+    'enable_mergejoin': Bool(90300, None),
+    'enable_nestloop': Bool(90300, None),
+    'enable_parallel_append': Bool(110000, None),
+    'enable_parallel_hash': Bool(110000, None),
+    'enable_partition_pruning': Bool(110000, None),
+    'enable_partitionwise_aggregate': Bool(110000, None),
+    'enable_partitionwise_join': Bool(110000, None),
+    'enable_seqscan': Bool(90300, None),
+    'enable_sort': Bool(90300, None),
+    'enable_tidscan': Bool(90300, None),
+    'escape_string_warning': Bool(90300, None),
+    'event_source': String(90300, None),
+    'exit_on_error': Bool(90300, None),
+    'external_pid_file': String(90300, None),
+    'extra_float_digits': Integer(90300, None, -15, 3, None),
+    'force_parallel_mode': EnumBool(90600, None, ('regress',)),
+    'from_collapse_limit': Integer(90300, None, 1, 2147483647, None),
+    'fsync': Bool(90300, None),
+    'full_page_writes': Bool(90300, None),
+    'geqo': Bool(90300, None),
+    'geqo_effort': Integer(90300, None, 1, 10, None),
+    'geqo_generations': Integer(90300, None, 0, 2147483647, None),
+    'geqo_pool_size': Integer(90300, None, 0, 2147483647, None),
+    'geqo_seed': Real(90300, None, 0, 1, None),
+    'geqo_selection_bias': Real(90300, None, 1.5, 2, None),
+    'geqo_threshold': Integer(90300, None, 2, 2147483647, None),
+    'gin_fuzzy_search_limit': Integer(90300, None, 0, 2147483647, None),
+    'gin_pending_list_limit': Integer(90500, None, 64, 2147483647, 'kB'),
+    'hash_mem_multiplier': Real(130000, None, 1, 1000, None),
+    'hba_file': String(90300, None),
+    'hot_standby': Bool(90300, None),
+    'hot_standby_feedback': Bool(90300, None),
+    'huge_pages': EnumBool(90400, None, ('try',)),
+    'ident_file': String(90300, None),
+    'idle_in_transaction_session_timeout': Integer(90600, None, 0, 2147483647, 'ms'),
+    'ignore_checksum_failure': Bool(90300, None),
+    'ignore_invalid_pages': Bool(130000, None),
+    'ignore_system_indexes': Bool(90300, None),
+    'IntervalStyle': Enum(90300, None, ('postgres', 'postgres_verbose', 'sql_standard', 'iso_8601')),
+    'jit': Bool(110000, None),
+    'jit_above_cost': Real(110000, None, -1, 1.79769e+308, None),
+    'jit_debugging_support': Bool(110000, None),
+    'jit_dump_bitcode': Bool(110000, None),
+    'jit_expressions': Bool(110000, None),
+    'jit_inline_above_cost': Real(110000, None, -1, 1.79769e+308, None),
+    'jit_optimize_above_cost': Real(110000, None, -1, 1.79769e+308, None),
+    'jit_profiling_support': Bool(110000, None),
+    'jit_provider': String(110000, None),
+    'jit_tuple_deforming': Bool(110000, None),
+    'join_collapse_limit': Integer(90300, None, 1, 2147483647, None),
+    'krb_caseins_users': Bool(90300, None),
+    'krb_server_keyfile': String(90300, None),
+    'krb_srvname': String(90300, 90400),
+    'lc_messages': String(90300, None),
+    'lc_monetary': String(90300, None),
+    'lc_numeric': String(90300, None),
+    'lc_time': String(90300, None),
+    'listen_addresses': String(90300, None),
+    'local_preload_libraries': String(90300, None),
+    'lock_timeout': Integer(90300, None, 0, 2147483647, 'ms'),
+    'lo_compat_privileges': Bool(90300, None),
+    'log_autovacuum_min_duration': Integer(90300, None, -1, 2147483647, 'ms'),
+    'log_checkpoints': Bool(90300, None),
+    'log_connections': Bool(90300, None),
+    'log_destination': String(90300, None),
+    'log_directory': String(90300, None),
+    'log_disconnections': Bool(90300, None),
+    'log_duration': Bool(90300, None),
+    'log_error_verbosity': Enum(90300, None, ('terse', 'default', 'verbose')),
+    'log_executor_stats': Bool(90300, None),
+    'log_file_mode': Integer(90300, None, 0, 511, None),
+    'log_filename': String(90300, None),
+    'logging_collector': Bool(90300, None),
+    'log_hostname': Bool(90300, None),
+    'logical_decoding_work_mem': Integer(130000, None, 64, 2147483647, 'kB'),
+    'log_line_prefix': String(90300, None),
+    'log_lock_waits': Bool(90300, None),
+    'log_min_duration_sample': Integer(130000, None, -1, 2147483647, 'ms'),
+    'log_min_duration_statement': Integer(90300, None, -1, 2147483647, 'ms'),
+    'log_min_error_statement': Enum(90300, None, ('debug5', 'debug4', 'debug3', 'debug2', 'debug1', 'info',
+                                                  'notice', 'warning', 'error', 'log', 'fatal', 'panic')),
+    'log_min_messages': Enum(90300, None, ('debug5', 'debug4', 'debug3', 'debug2', 'debug1', 'info',
+                                           'notice', 'warning', 'error', 'log', 'fatal', 'panic')),
+    'log_parameter_max_length': Integer(130000, None, -1, 1073741823, 'B'),
+    'log_parameter_max_length_on_error': Integer(130000, None, -1, 1073741823, 'B'),
+    'log_parser_stats': Bool(90300, None),
+    'log_planner_stats': Bool(90300, None),
+    'log_replication_commands': Bool(90500, None),
+    'log_rotation_age': Integer(90300, None, 0, 35791394, 'min'),
+    'log_rotation_size': Integer(90300, None, 0, 2097151, 'kB'),
+    'log_statement': Enum(90300, None, ('none', 'ddl', 'mod', 'all')),
+    'log_statement_sample_rate': Real(130000, None, 0, 1, None),
+    'log_statement_stats': Bool(90300, None),
+    'log_temp_files': Integer(90300, None, -1, 2147483647, 'kB'),
+    'log_timezone': String(90300, None),
+    'log_transaction_sample_rate': Real(120000, None, 0, 1, None),
+    'log_truncate_on_rotation': Bool(90300, None),
+    'maintenance_io_concurrency': Integer(130000, None, 0, 1000, None),
+    'maintenance_work_mem': Integer(90300, None, 1024, 2147483647, 'kB'),
+    'max_connections': (
+        Integer(90300, 90600, 1, 8388607, None),
+        Integer(90600, None, 1, 262143, None)
+    ),
+    'max_files_per_process': (
+        Integer(90300, 130000, 25, 2147483647, None),
+        Integer(130000, None, 64, 2147483647, None)
+    ),
+    'max_locks_per_transaction': Integer(90300, None, 10, 2147483647, None),
+    'max_logical_replication_workers': Integer(100000, None, 0, 262143, None),
+    'max_parallel_maintenance_workers': Integer(110000, None, 0, 1024, None),
+    'max_parallel_workers': Integer(100000, None, 0, 1024, None),
+    'max_parallel_workers_per_gather': Integer(90600, None, 0, 1024, None),
+    'max_pred_locks_per_page': Integer(100000, None, 0, 2147483647, None),
+    'max_pred_locks_per_relation': Integer(100000, None, -2147483648, 2147483647, None),
+    'max_pred_locks_per_transaction': Integer(90300, None, 10, 2147483647, None),
+    'max_prepared_transactions': (
+        Integer(90300, 90600, 0, 8388607, None),
+        Integer(90600, None, 0, 262143, None)
+    ),
+    'max_replication_slots': (
+        Integer(90400, 90600, 0, 8388607, None),
+        Integer(90600, None, 0, 262143, None)
+    ),
+    'max_slot_wal_keep_size': Integer(130000, None, -1, 2147483647, 'MB'),
+    'max_stack_depth': Integer(90300, None, 100, 2147483647, 'kB'),
+    'max_standby_archive_delay': Integer(90300, None, -1, 2147483647, 'ms'),
+    'max_standby_streaming_delay': Integer(90300, None, -1, 2147483647, 'ms'),
+    'max_sync_workers_per_subscription': Integer(100000, None, 0, 262143, None),
+    'max_wal_senders': (
+        Integer(90300, 90600, 0, 8388607, None),
+        Integer(90600, None, 0, 262143, None)
+    ),
+    'max_wal_size': (
+        Integer(90500, 100000, 2, 2147483647, '16MB'),
+        Integer(100000, None, 2, 2147483647, 'MB')
+    ),
+    'max_worker_processes': (
+        Integer(90400, 90600, 1, 8388607, None),
+        Integer(90600, None, 0, 262143, None)
+    ),
+    'min_parallel_index_scan_size': Integer(100000, None, 0, 715827882, '8kB'),
+    'min_parallel_relation_size': Integer(90600, 100000, 0, 715827882, '8kB'),
+    'min_parallel_table_scan_size': Integer(100000, None, 0, 715827882, '8kB'),
+    'min_wal_size': (
+        Integer(90500, 100000, 2, 2147483647, '16MB'),
+        Integer(100000, None, 2, 2147483647, 'MB')
+    ),
+    'old_snapshot_threshold': Integer(90600, None, -1, 86400, 'min'),
+    'operator_precedence_warning': Bool(90500, None),
+    'parallel_leader_participation': Bool(110000, None),
+    'parallel_setup_cost': Real(90600, None, 0, 1.79769e+308, None),
+    'parallel_tuple_cost': Real(90600, None, 0, 1.79769e+308, None),
+    'password_encryption': (
+        Bool(90300, 100000),
+        Enum(100000, None, ('md5', 'scram-sha-256'))
+    ),
+    'plan_cache_mode': Enum(120000, None, ('auto', 'force_generic_plan', 'force_custom_plan')),
+    'port': Integer(90300, None, 1, 65535, None),
+    'post_auth_delay': Integer(90300, None, 0, 2147, 's'),
+    'pre_auth_delay': Integer(90300, None, 0, 60, 's'),
+    'quote_all_identifiers': Bool(90300, None),
+    'random_page_cost': Real(90300, None, 0, 1.79769e+308, None),
+    'replacement_sort_tuples': Integer(90600, 110000, 0, 2147483647, None),
+    'restart_after_crash': Bool(90300, None),
+    'row_security': Bool(90500, None),
+    'search_path': String(90300, None),
+    'seq_page_cost': Real(90300, None, 0, 1.79769e+308, None),
+    'session_preload_libraries': String(90400, None),
+    'session_replication_role': Enum(90300, None, ('origin', 'replica', 'local')),
+    'shared_buffers': Integer(90300, None, 16, 1073741823, '8kB'),
+    'shared_memory_type': Enum(120000, None, ('sysv', 'mmap')),
+    'shared_preload_libraries': String(90300, None),
+    'sql_inheritance': Bool(90300, 100000),
+    'ssl': Bool(90300, None),
+    'ssl_ca_file': String(90300, None),
+    'ssl_cert_file': String(90300, None),
+    'ssl_ciphers': String(90300, None),
+    'ssl_crl_file': String(90300, None),
+    'ssl_dh_params_file': String(100000, None),
+    'ssl_ecdh_curve': String(90400, None),
+    'ssl_key_file': String(90300, None),
+    'ssl_max_protocol_version': Enum(120000, None, ('', 'tlsv1', 'tlsv1.1', 'tlsv1.2', 'tlsv1.3')),
+    'ssl_min_protocol_version': Enum(120000, None, ('tlsv1', 'tlsv1.1', 'tlsv1.2', 'tlsv1.3')),
+    'ssl_passphrase_command': String(110000, None),
+    'ssl_passphrase_command_supports_reload': Bool(110000, None),
+    'ssl_prefer_server_ciphers': Bool(90400, None),
+    'ssl_renegotiation_limit': Integer(90300, 90500, 0, 2147483647, 'kB'),
+    'standard_conforming_strings': Bool(90300, None),
+    'statement_timeout': Integer(90300, None, 0, 2147483647, 'ms'),
+    'stats_temp_directory': String(90300, None),
+    'superuser_reserved_connections': (
+        Integer(90300, 90600, 0, 8388607, None),
+        Integer(90600, None, 0, 262143, None),
+    ),
+    'synchronize_seqscans': Bool(90300, None),
+    'synchronous_commit': (
+        EnumBool(90300, 90600, ('local', 'remote_write')),
+        EnumBool(90600, None, ('local', 'remote_write', 'remote_apply'))
+    ),
+    'synchronous_standby_names': String(90300, None),
+    'syslog_facility': Enum(90300, None, ('local0', 'local1', 'local2', 'local3',
+                                          'local4', 'local5', 'local6', 'local7')),
+    'syslog_ident': String(90300, None),
+    'syslog_sequence_numbers': Bool(90600, None),
+    'syslog_split_messages': Bool(90600, None),
+    'tcp_keepalives_count': Integer(90300, None, 0, 2147483647, None),
+    'tcp_keepalives_idle': Integer(90300, None, 0, 2147483647, 's'),
+    'tcp_keepalives_interval': Integer(90300, None, 0, 2147483647, 's'),
+    'tcp_user_timeout': Integer(120000, None, 0, 2147483647, 'ms'),
+    'temp_buffers': Integer(90300, None, 100, 1073741823, '8kB'),
+    'temp_file_limit': Integer(90300, None, -1, 2147483647, 'kB'),
+    'temp_tablespaces': String(90300, None),
+    'TimeZone': String(90300, None),
+    'timezone_abbreviations': String(90300, None),
+    'trace_notify': Bool(90300, None),
+    'trace_recovery_messages': Enum(90300, None, ('debug5', 'debug4', 'debug3', 'debug2',
+                                                  'debug1', 'log', 'notice', 'warning', 'error')),
+    'trace_sort': Bool(90300, None),
+    'track_activities': Bool(90300, None),
+    'track_activity_query_size': (
+        Integer(90300, 110000, 100, 102400, None),
+        Integer(110000, 130000, 100, 102400, 'B'),
+        Integer(130000, None, 100, 1048576, 'B')
+    ),
+    'track_commit_timestamp': Bool(90500, None),
+    'track_counts': Bool(90300, None),
+    'track_functions': Enum(90300, None, ('none', 'pl', 'all')),
+    'track_io_timing': Bool(90300, None),
+    'transaction_deferrable': Bool(90300, None),
+    'transaction_isolation': Enum(90300, None, ('serializable', 'repeatable read',
+                                                'read committed', 'read uncommitted')),
+    'transaction_read_only': Bool(90300, None),
+    'transform_null_equals': Bool(90300, None),
+    'unix_socket_directories': String(90300, None),
+    'unix_socket_group': String(90300, None),
+    'unix_socket_permissions': Integer(90300, None, 0, 511, None),
+    'update_process_title': Bool(90300, None),
+    'vacuum_cleanup_index_scale_factor': Real(110000, None, 0, 1e+10, None),
+    'vacuum_cost_delay': (
+        Integer(90300, 120000, 0, 100, 'ms'),
+        Real(120000, None, 0, 100, 'ms')
+    ),
+    'vacuum_cost_limit': Integer(90300, None, 1, 10000, None),
+    'vacuum_cost_page_dirty': Integer(90300, None, 0, 10000, None),
+    'vacuum_cost_page_hit': Integer(90300, None, 0, 10000, None),
+    'vacuum_cost_page_miss': Integer(90300, None, 0, 10000, None),
+    'vacuum_defer_cleanup_age': Integer(90300, None, 0, 1000000, None),
+    'vacuum_freeze_min_age': Integer(90300, None, 0, 1000000000, None),
+    'vacuum_freeze_table_age': Integer(90300, None, 0, 2000000000, None),
+    'vacuum_multixact_freeze_min_age': Integer(90300, None, 0, 1000000000, None),
+    'vacuum_multixact_freeze_table_age': Integer(90300, None, 0, 2000000000, None),
+    'wal_buffers': Integer(90300, None, -1, 262143, '8kB'),
+    'wal_compression': Bool(90500, None),
+    'wal_consistency_checking': String(100000, None),
+    'wal_init_zero': Bool(120000, None),
+    'wal_keep_segments': Integer(90300, 130000, 0, 2147483647, None),
+    'wal_keep_size': Integer(130000, None, 0, 2147483647, 'MB'),
+    'wal_level': (
+        Enum(90300, 90400, ('minimal', 'archive', 'hot_standby')),
+        Enum(90400, 90600, ('minimal', 'archive', 'hot_standby', 'logical')),
+        Enum(90600, None, ('minimal', 'replica', 'logical'))
+    ),
+    'wal_log_hints': Bool(90400, None),
+    'wal_receiver_create_temp_slot': Bool(130000, None),
+    'wal_receiver_status_interval': Integer(90300, None, 0, 2147483, 's'),
+    'wal_receiver_timeout': Integer(90300, None, 0, 2147483647, 'ms'),
+    'wal_recycle': Bool(120000, None),
+    'wal_retrieve_retry_interval': Integer(90500, None, 1, 2147483647, 'ms'),
+    'wal_sender_timeout': Integer(90300, None, 0, 2147483647, 'ms'),
+    'wal_skip_threshold': Integer(130000, None, 0, 2147483647, 'kB'),
+    'wal_sync_method': Enum(90300, None, ('fsync', 'fdatasync', 'open_sync', 'open_datasync')),
+    'wal_writer_delay': Integer(90300, None, 1, 10000, 'ms'),
+    'wal_writer_flush_after': Integer(90600, None, 0, 2147483647, '8kB'),
+    'work_mem': Integer(90300, None, 64, 2147483647, 'kB'),
+    'xmlbinary': Enum(90300, None, ('base64', 'hex')),
+    'xmloption': Enum(90300, None, ('content', 'document')),
+    'zero_damaged_pages': Bool(90300, None)
+})
+
+
+recovery_parameters = CaseInsensitiveDict({
+    'archive_cleanup_command': String(90300, None),
+    'pause_at_recovery_target': Bool(90300, 90500),
+    'primary_conninfo': String(90300, None),
+    'primary_slot_name': String(90400, None),
+    'promote_trigger_file': String(120000, None),
+    'recovery_end_command': String(90300, None),
+    'recovery_min_apply_delay': Integer(90400, None, 0, 2147483647, 'ms'),
+    'recovery_target': Enum(90400, None, ('immediate',)),
+    'recovery_target_action': Enum(90500, None, ('pause', 'promote', 'shutdown')),
+    'recovery_target_inclusive': Bool(90300, None),
+    'recovery_target_lsn': String(100000, None),
+    'recovery_target_name': String(90400, None),
+    'recovery_target_time': String(90300, None),
+    'recovery_target_timeline': String(90300, None),
+    'recovery_target_xid': String(90300, None),
+    'restore_command': String(90300, None),
+    'standby_mode': Bool(90300, 120000),
+    'trigger_file': String(90300, 120000)
+})
+
+
+def _transform_parameter_value(validators, version, name, value):
+    validators = validators.get(name)
+    if validators:
+        for validator in (validators if isinstance(validators[0], tuple) else [validators]):
+            if version >= validator.version_from and\
+                    (validator.version_till is None or version < validator.version_till):
+                return validator.transform(name, value)
+    logger.warning('Removing unexpected parameter=%s value=%s from the config', name, value)
+
+
+def transform_postgresql_parameter_value(version, name, value):
+    if '.' in name:
+        return value
+    return _transform_parameter_value(parameters, version, name, value)
+
+
+def transform_recovery_parameter_value(version, name, value):
+    return _transform_parameter_value(recovery_parameters, version, name, value)

patroni/raft_controller.py

@@ -0,0 +1,34 @@
+import logging
+import os
+
+from patroni.daemon import AbstractPatroniDaemon, abstract_main
+from patroni.dcs.raft import KVStoreTTL
+from pysyncobj import SyncObjConf
+
+logger = logging.getLogger(__name__)
+
+
+class RaftController(AbstractPatroniDaemon):
+
+    def __init__(self, config):
+        super(RaftController, self).__init__(config)
+
+        raft_config = self.config.get('raft')
+        self_addr = raft_config['self_addr']
+        template = os.path.join(raft_config.get('data_dir', ''), self_addr)
+        self._syncobj_config = SyncObjConf(autoTick=False, appendEntriesUseBatch=False, dynamicMembershipChange=True,
+                                           journalFile=template + '.journal', fullDumpFile=template + '.dump')
+        self._raft = KVStoreTTL(self_addr, raft_config.get('partner_addrs', []), self._syncobj_config)
+
+    def _run_cycle(self):
+        try:
+            self._raft.doTick(self._syncobj_config.autoTickPeriod)
+        except Exception:
+            logger.exception('doTick')
+
+    def _shutdown(self):
+        self._raft.destroy()
+
+
+def main():
+    abstract_main(RaftController)

patroni/request.py

@@ -0,0 +1,58 @@
+import json
+import urllib3
+import six
+
+from six.moves.urllib_parse import urlparse, urlunparse
+
+from .utils import USER_AGENT
+
+
+class PatroniRequest(object):
+
+    def __init__(self, config, insecure=False):
+        cert_reqs = 'CERT_NONE' if insecure or config.get('ctl', {}).get('insecure', False) else 'CERT_REQUIRED'
+        self._pool = urllib3.PoolManager(num_pools=10, maxsize=10, cert_reqs=cert_reqs)
+        self.reload_config(config)
+
+    @staticmethod
+    def _get_cfg_value(config, name):
+        return config.get('ctl', {}).get(name) or config.get('restapi', {}).get(name)
+
+    def _apply_pool_param(self, param, value):
+        if value:
+            self._pool.connection_pool_kw[param] = value
+        else:
+            self._pool.connection_pool_kw.pop(param, None)
+
+    def _apply_ssl_file_param(self, config, name):
+        value = self._get_cfg_value(config, name + 'file')
+        self._apply_pool_param(name + '_file', value)
+        return value
+
+    def reload_config(self, config):
+        self._pool.headers = urllib3.make_headers(basic_auth=self._get_cfg_value(config, 'auth'), user_agent=USER_AGENT)
+
+        if self._apply_ssl_file_param(config, 'cert'):
+            self._apply_ssl_file_param(config, 'key')
+        else:
+            self._pool.connection_pool_kw.pop('key_file', None)
+
+        cacert = config.get('ctl', {}).get('cacert') or config.get('restapi', {}).get('cafile')
+        self._apply_pool_param('ca_certs', cacert)
+
+    def request(self, method, url, body=None, **kwargs):
+        if body is not None and not isinstance(body, six.string_types):
+            body = json.dumps(body)
+        return self._pool.request(method.upper(), url, body=body, **kwargs)
+
+    def __call__(self, member, method='GET', endpoint=None, data=None, **kwargs):
+        url = member.api_url
+        if endpoint:
+            scheme, netloc, _, _, _, _ = urlparse(url)
+            url = urlunparse((scheme, netloc, endpoint, '', '', ''))
+        return self.request(method, url, data, **kwargs)
+
+
+def get(url, verify=True, **kwargs):
+    http = PatroniRequest({}, not verify)
+    return http.request('GET', url, **kwargs)

patroni/scripts/aws.py

@@ -1,12 +1,12 @@
 #!/usr/bin/env python
 
+import json
 import logging
-import requests
-from requests.exceptions import RequestException
 import sys
 import boto.ec2
 
 from patroni.utils import Retry, RetryFailedError
+from patroni.request import get as requests_get
 
 logger = logging.getLogger(__name__)
 
@@ -19,14 +19,14 @@ class AWSConnection(object):
         self._retry = Retry(deadline=300, max_delay=30, max_tries=-1, retry_exceptions=(boto.exception.StandardError,))
         try:
             # get the instance id
-            r = requests.get('http://169.254.169.254/latest/dynamic/instance-identity/document', timeout=2.1)
+            r = requests_get('http://169.254.169.254/latest/dynamic/instance-identity/document', timeout=2.1)
-        except RequestException:
+        except Exception:
             logger.error('cannot query AWS meta-data')
             return
 
-        if r.ok:
+        if r.status < 400:
             try:
-                content = r.json()
+                content = json.loads(r.data.decode('utf-8'))
                 self.instance_id = content['instanceId']
                 self.region = content['region']
             except Exception:

patroni/utils.py

@@ -1,15 +1,24 @@
+import json.decoder as json_decoder
 import logging
+import os
+import platform
 import random
 import re
+import socket
+import sys
+import tempfile
 import time
 
 from dateutil import tz
-from patroni.exceptions import PatroniException
+
+from .exceptions import PatroniException
+from .version import __version__
 
 tzutc = tz.tzutc()
 
 logger = logging.getLogger(__name__)
 
+USER_AGENT = 'Patroni/{0} Python/{1} {2}'.format(__version__, platform.python_version(), platform.system())
 OCT_RE = re.compile(r'^[-+]?0[0-7]*')
 DEC_RE = re.compile(r'^[-+]?(0|[1-9][0-9]*)')
 HEX_RE = re.compile(r'^[-+]?0x[0-9a-fA-F]+')
@@ -296,6 +305,17 @@ class Retry(object):
                      max_jitter=self.max_jitter / 100.0, max_delay=self.max_delay, sleep_func=self.sleep_func,
                      deadline=self.deadline, retry_exceptions=self.retry_exceptions)
 
+    @property
+    def sleeptime(self):
+        return self._cur_delay + (random.randint(0, self.max_jitter) / 100.0)
+
+    def update_delay(self):
+        self._cur_delay = min(self._cur_delay * self.backoff, self.max_delay)
+
+    @property
+    def stoptime(self):
+        return self._cur_stoptime
+
     def __call__(self, func, *args, **kwargs):
         """Call a function with arguments until it completes without throwing a `retry_exceptions`
 
@@ -317,14 +337,14 @@ class Retry(object):
                     logger.warning('Retry got exception: %s', e)
                     raise RetryFailedError("Too many retry attempts")
                 self._attempts += 1
-                sleeptime = self._cur_delay + (random.randint(0, self.max_jitter) / 100.0)
+                sleeptime = hasattr(e, 'sleeptime') and e.sleeptime or self.sleeptime
 
                 if self._cur_stoptime is not None and time.time() + sleeptime >= self._cur_stoptime:
                     logger.warning('Retry got exception: %s', e)
                     raise RetryFailedError("Exceeded retry deadline")
                 logger.debug('Retry got exception: %s', e)
                 self.sleep_func(sleeptime)
-                self._cur_delay = min(self._cur_delay * self.backoff, self.max_delay)
+                self.update_delay()
 
 
 def polling_loop(timeout, interval=1):
@@ -340,6 +360,8 @@ def polling_loop(timeout, interval=1):
 
 def split_host_port(value, default_port):
     t = value.rsplit(':', 1)
+    if ':' in t[0]:
+        t[0] = t[0].strip('[]')
     t.append(default_port)
     return t[0], int(t[1])
 
@@ -352,3 +374,141 @@ def uri(proto, netloc, path='', user=None):
     path = '/{0}'.format(path) if path and not path.startswith('/') else path
     user = '{0}@'.format(user) if user else ''
     return '{0}://{1}{2}{3}{4}'.format(proto, user, host, port, path)
+
+
+def iter_response_objects(response):
+    prev = ''
+    decoder = json_decoder.JSONDecoder()
+    for chunk in response.read_chunked(decode_content=False):
+        if isinstance(chunk, bytes):
+            chunk = chunk.decode('utf-8')
+        chunk = prev + chunk
+
+        length = len(chunk)
+        idx = json_decoder.WHITESPACE.match(chunk, 0).end()
+        while idx < length:
+            try:
+                message, idx = decoder.raw_decode(chunk, idx)
+            except ValueError:  # malformed or incomplete JSON, unlikely to happen
+                break
+            else:
+                yield message
+                idx = json_decoder.WHITESPACE.match(chunk, idx).end()
+        prev = chunk[idx:]
+
+
+def is_standby_cluster(config):
+    # Check whether or not provided configuration describes a standby cluster
+    return isinstance(config, dict) and (config.get('host') or config.get('port') or config.get('restore_command'))
+
+
+def cluster_as_json(cluster):
+    leader_name = cluster.leader.name if cluster.leader else None
+    xlog_location_cluster = cluster.last_leader_operation or 0
+
+    ret = {'members': []}
+    for m in cluster.members:
+        if m.name == leader_name:
+            config = cluster.config.data if cluster.config and cluster.config.modify_index else {}
+            role = 'standby_leader' if is_standby_cluster(config.get('standby_cluster')) else 'leader'
+        elif m.name in cluster.sync.members:
+            role = 'sync_standby'
+        else:
+            role = 'replica'
+
+        member = {'name': m.name, 'role': role, 'state': m.data.get('state', ''), 'api_url': m.api_url}
+        conn_kwargs = m.conn_kwargs()
+        if conn_kwargs.get('host'):
+            member['host'] = conn_kwargs['host']
+            if conn_kwargs.get('port'):
+                member['port'] = int(conn_kwargs['port'])
+        optional_attributes = ('timeline', 'pending_restart', 'scheduled_restart', 'tags')
+        member.update({n: m.data[n] for n in optional_attributes if n in m.data})
+
+        if m.name != leader_name:
+            xlog_location = m.data.get('xlog_location')
+            if xlog_location is None:
+                member['lag'] = 'unknown'
+            elif xlog_location_cluster >= xlog_location:
+                member['lag'] = xlog_location_cluster - xlog_location
+            else:
+                member['lag'] = 0
+
+        ret['members'].append(member)
+
+    # sort members by name for consistency
+    ret['members'].sort(key=lambda m: m['name'])
+    if cluster.is_paused():
+        ret['pause'] = True
+    if cluster.failover and cluster.failover.scheduled_at:
+        ret['scheduled_switchover'] = {'at': cluster.failover.scheduled_at.isoformat()}
+        if cluster.failover.leader:
+            ret['scheduled_switchover']['from'] = cluster.failover.leader
+        if cluster.failover.candidate:
+            ret['scheduled_switchover']['to'] = cluster.failover.candidate
+    return ret
+
+
+def is_subpath(d1, d2):
+    real_d1 = os.path.realpath(d1) + os.path.sep
+    real_d2 = os.path.realpath(os.path.join(real_d1, d2))
+    return os.path.commonprefix([real_d1, real_d2 + os.path.sep]) == real_d1
+
+
+def validate_directory(d, msg="{} {}"):
+    if not os.path.exists(d):
+        try:
+            os.makedirs(d)
+        except OSError as e:
+            logger.error(e)
+            raise PatroniException(msg.format(d, "couldn't create the directory"))
+    elif os.path.isdir(d):
+        try:
+            fd, tmpfile = tempfile.mkstemp(dir=d)
+            os.close(fd)
+            os.remove(tmpfile)
+        except OSError:
+            raise PatroniException(msg.format(d, "the directory is not writable"))
+    else:
+        raise PatroniException(msg.format(d, "is not a directory"))
+
+
+def data_directory_is_empty(data_dir):
+    if not os.path.exists(data_dir):
+        return True
+    return all(os.name != 'nt' and (n.startswith('.') or n == 'lost+found') for n in os.listdir(data_dir))
+
+
+def keepalive_intvl(timeout, idle, cnt=3):
+    return max(1, int(float(timeout - idle) / cnt))
+
+
+def keepalive_socket_options(timeout, idle, cnt=3):
+    yield (socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
+
+    if sys.platform.startswith('linux'):
+        yield (socket.SOL_TCP, 18, int(timeout * 1000))  # TCP_USER_TIMEOUT
+        TCP_KEEPIDLE = getattr(socket, 'TCP_KEEPIDLE', None)
+        TCP_KEEPINTVL = getattr(socket, 'TCP_KEEPINTVL', None)
+        TCP_KEEPCNT = getattr(socket, 'TCP_KEEPCNT', None)
+    elif sys.platform.startswith('darwin'):
+        TCP_KEEPIDLE = 0x10  # (named "TCP_KEEPALIVE" in C)
+        TCP_KEEPINTVL = 0x101
+        TCP_KEEPCNT = 0x102
+    else:
+        return
+
+    intvl = keepalive_intvl(timeout, idle, cnt)
+    yield (socket.IPPROTO_TCP, TCP_KEEPIDLE, idle)
+    yield (socket.IPPROTO_TCP, TCP_KEEPINTVL, intvl)
+    yield (socket.IPPROTO_TCP, TCP_KEEPCNT, cnt)
+
+
+def enable_keepalive(sock, timeout, idle, cnt=3):
+    SIO_KEEPALIVE_VALS = getattr(socket, 'SIO_KEEPALIVE_VALS', None)
+    if SIO_KEEPALIVE_VALS is not None:  # Windows
+        intvl = keepalive_intvl(timeout, idle, cnt)
+        return sock.ioctl(SIO_KEEPALIVE_VALS, (1, idle * 1000, intvl * 1000))
+
+    for opt in keepalive_socket_options(timeout, idle, cnt):
+        sock.setsockopt(*opt)

patroni/validator.py

@@ -0,0 +1,379 @@
+#!/usr/bin/env python3
+import os
+import socket
+import re
+import subprocess
+
+from patroni.utils import split_host_port, data_directory_is_empty
+from patroni.ctl import find_executable
+from patroni.dcs import dcs_modules
+from patroni.exceptions import ConfigParseError
+from six import string_types
+
+
+def data_directory_empty(data_dir):
+    if os.path.isfile(os.path.join(data_dir, "global", "pg_control")):
+        return False
+    return data_directory_is_empty(data_dir)
+
+
+def validate_connect_address(address):
+    try:
+        host, _ = split_host_port(address, 1)
+    except (AttributeError, TypeError, ValueError):
+        raise ConfigParseError("contains a wrong value")
+    if host in ["127.0.0.1", "0.0.0.0", "*", "::1", "localhost"]:
+        raise ConfigParseError('must not contain "127.0.0.1", "0.0.0.0", "*", "::1", "localhost"')
+    return True
+
+
+def validate_host_port(host_port, listen=False, multiple_hosts=False):
+    try:
+        hosts, port = split_host_port(host_port, None)
+    except (ValueError, TypeError):
+        raise ConfigParseError("contains a wrong value")
+    else:
+        if multiple_hosts:
+            hosts = hosts.split(",")
+        else:
+            hosts = [hosts]
+        for host in hosts:
+            proto = socket.getaddrinfo(host, "", 0, socket.SOCK_STREAM, 0, socket.AI_PASSIVE)
+            s = socket.socket(proto[0][0], socket.SOCK_STREAM)
+            try:
+                if s.connect_ex((host, port)) == 0:
+                    if listen:
+                        raise ConfigParseError("Port {} is already in use.".format(port))
+                elif not listen:
+                    raise ConfigParseError("{} is not reachable".format(host_port))
+            except socket.gaierror as e:
+                raise ConfigParseError(e)
+            finally:
+                s.close()
+    return True
+
+
+def comma_separated_host_port(string):
+    assert all([validate_host_port(s.strip()) for s in string.split(",")]), "didn't pass the validation"
+    return True
+
+
+def validate_host_port_listen(host_port):
+    return validate_host_port(host_port, listen=True)
+
+
+def validate_host_port_listen_multiple_hosts(host_port):
+    return validate_host_port(host_port, listen=True, multiple_hosts=True)
+
+
+def is_ipv4_address(ip):
+    try:
+        socket.inet_aton(ip)
+    except Exception:
+        raise ConfigParseError("Is not a valid ipv4 address")
+    return True
+
+
+def is_ipv6_address(ip):
+    try:
+        socket.inet_pton(socket.AF_INET6, ip)
+    except Exception:
+        raise ConfigParseError("Is not a valid ipv6 address")
+    return True
+
+
+def get_major_version(bin_dir=None):
+    if not bin_dir:
+        binary = 'postgres'
+    else:
+        binary = os.path.join(bin_dir, 'postgres')
+    version = subprocess.check_output([binary, '--version']).decode()
+    version = re.match(r'^[^\s]+ [^\s]+ (\d+)(\.(\d+))?', version)
+    return '.'.join([version.group(1), version.group(3)]) if int(version.group(1)) < 10 else version.group(1)
+
+
+def validate_data_dir(data_dir):
+    if not data_dir:
+        raise ConfigParseError("is an empty string")
+    elif os.path.exists(data_dir) and not os.path.isdir(data_dir):
+        raise ConfigParseError("is not a directory")
+    elif not data_directory_empty(data_dir):
+        if not os.path.exists(os.path.join(data_dir, "PG_VERSION")):
+            raise ConfigParseError("doesn't look like a valid data directory")
+        else:
+            with open(os.path.join(data_dir, "PG_VERSION"), "r") as version:
+                pgversion = version.read().strip()
+            waldir = ("pg_wal" if float(pgversion) >= 10 else "pg_xlog")
+            if not os.path.isdir(os.path.join(data_dir, waldir)):
+                raise ConfigParseError("data dir for the cluster is not empty, but doesn't contain"
+                                       " \"{}\" directory".format(waldir))
+            bin_dir = schema.data.get("postgresql", {}).get("bin_dir", None)
+            major_version = get_major_version(bin_dir)
+            if pgversion != major_version:
+                raise ConfigParseError("data_dir directory postgresql version ({}) doesn't match with "
+                                       "'postgres --version' output ({})".format(pgversion, major_version))
+    return True
+
+
+class Result(object):
+    def __init__(self, status, error="didn't pass validation", level=0, path="", data=""):
+        self.status = status
+        self.path = path
+        self.data = data
+        self.level = level
+        self._error = error
+        if not self.status:
+            self.error = error
+        else:
+            self.error = None
+
+    def __repr__(self):
+        return self.path + (" " + str(self.data) + " " + self._error if self.error else "")
+
+
+class Case(object):
+    def __init__(self, schema):
+        self._schema = schema
+
+
+class Or(object):
+    def __init__(self, *args):
+        self.args = args
+
+
+class Optional(object):
+    def __init__(self, name):
+        self.name = name
+
+
+class Directory(object):
+    def __init__(self, contains=None, contains_executable=None):
+        self.contains = contains
+        self.contains_executable = contains_executable
+
+    def validate(self, name):
+        if not name:
+            yield Result(False, "is an empty string")
+        elif not os.path.exists(name):
+            yield Result(False, "Directory '{}' does not exist.".format(name))
+        elif not os.path.isdir(name):
+            yield Result(False, "'{}' is not a directory.".format(name))
+        else:
+            if self.contains:
+                for path in self.contains:
+                    if not os.path.exists(os.path.join(name, path)):
+                        yield Result(False, "'{}' does not contain '{}'".format(name, path))
+            if self.contains_executable:
+                for program in self.contains_executable:
+                    if not find_executable(program, name):
+                        yield Result(False, "'{}' does not contain '{}'".format(name, program))
+
+
+class Schema(object):
+    def __init__(self, validator):
+        self.validator = validator
+
+    def __call__(self, data):
+        for i in self.validate(data):
+            if not i.status:
+                print(i)
+
+    def validate(self, data):
+        self.data = data
+        if isinstance(self.validator, string_types):
+            yield Result(isinstance(self.data, string_types), "is not a string", level=1, data=self.data)
+        elif issubclass(type(self.validator), type):
+            validator = self.validator
+            if self.validator == str:
+                validator = string_types
+            yield Result(isinstance(self.data, validator),
+                         "is not {}".format(_get_type_name(self.validator)), level=1, data=self.data)
+        elif callable(self.validator):
+            if hasattr(self.validator, "expected_type"):
+                if not isinstance(data, self.validator.expected_type):
+                    yield Result(False, "is not {}"
+                                 .format(_get_type_name(self.validator.expected_type)), level=1, data=self.data)
+                    return
+            try:
+                self.validator(data)
+                yield Result(True, data=self.data)
+            except Exception as e:
+                yield Result(False, "didn't pass validation: {}".format(e), data=self.data)
+        elif isinstance(self.validator, dict):
+            if not len(self.validator):
+                yield Result(isinstance(self.data, dict), "is not a dictionary", level=1, data=self.data)
+        elif isinstance(self.validator, list):
+            if not isinstance(self.data, list):
+                yield Result(isinstance(self.data, list), "is not a list", level=1, data=self.data)
+                return
+        for i in self.iter():
+            yield i
+
+    def iter(self):
+        if isinstance(self.validator, dict):
+            if not isinstance(self.data, dict):
+                yield Result(False, "is not a dictionary.", level=1)
+            else:
+                for i in self.iter_dict():
+                    yield i
+        elif isinstance(self.validator, list):
+            if len(self.data) == 0:
+                yield Result(False, "is an empty list", data=self.data)
+            if len(self.validator) > 0:
+                for key, value in enumerate(self.data):
+                    for v in Schema(self.validator[0]).validate(value):
+                        yield Result(v.status, v.error,
+                                     path=(str(key) + ("." + v.path if v.path else "")), level=v.level, data=value)
+        elif isinstance(self.validator, Directory):
+            for v in self.validator.validate(self.data):
+                yield v
+        elif isinstance(self.validator, Or):
+            for i in self.iter_or():
+                yield i
+
+    def iter_dict(self):
+        for key in self.validator.keys():
+            for d in self._data_key(key):
+                if d not in self.data and not isinstance(key, Optional):
+                    yield Result(False, "is not defined.", path=d)
+                elif d not in self.data and isinstance(key, Optional):
+                    continue
+                else:
+                    validator = self.validator[key]
+                    if isinstance(key, Or) and isinstance(self.validator[key], Case):
+                        validator = self.validator[key]._schema[d]
+                    for v in Schema(validator).validate(self.data[d]):
+                        yield Result(v.status, v.error,
+                                     path=(d + ("." + v.path if v.path else "")), level=v.level, data=v.data)
+
+    def iter_or(self):
+        results = []
+        for a in self.validator.args:
+            r = []
+            for v in Schema(a).validate(self.data):
+                r.append(v)
+            if any([x.status for x in r]) and not all([x.status for x in r]):
+                results += filter(lambda x: not x.status, r)
+            else:
+                results += r
+        if not any([x.status for x in results]):
+            max_level = 3
+            for v in sorted(results, key=lambda x: x.level):
+                if v.level > max_level:
+                    break
+                max_level = v.level
+                yield Result(v.status, v.error, path=v.path, level=v.level, data=v.data)
+
+    def _data_key(self, key):
+        if isinstance(self.data, dict) and isinstance(key, str):
+            yield key
+        elif isinstance(key, Optional):
+            yield key.name
+        elif isinstance(key, Or):
+            if any([i in self.data for i in key.args]):
+                for i in key.args:
+                    if i in self.data:
+                        yield i
+            else:
+                for i in key.args:
+                    yield i
+
+
+def _get_type_name(python_type):
+    return {str: 'a string', int: 'and integer', float: 'a number', bool: 'a boolean',
+            list: 'an array', dict: 'a dictionary', string_types: "a string"}.get(
+                    python_type, getattr(python_type, __name__, "unknown type"))
+
+
+def assert_(condition, message="Wrong value"):
+    assert condition, message
+
+
+userattributes = {"username": "", Optional("password"): ""}
+available_dcs = [m.split(".")[-1] for m in dcs_modules()]
+comma_separated_host_port.expected_type = string_types
+validate_connect_address.expected_type = string_types
+validate_host_port_listen.expected_type = string_types
+validate_host_port_listen_multiple_hosts.expected_type = string_types
+validate_data_dir.expected_type = string_types
+
+schema = Schema({
+  "name": str,
+  "scope": str,
+  "restapi": {
+    "listen": validate_host_port_listen,
+    "connect_address": validate_connect_address
+  },
+  Optional("bootstrap"): {
+    "dcs": {
+        Optional("ttl"): int,
+        Optional("loop_wait"): int,
+        Optional("retry_timeout"): int,
+        Optional("maximum_lag_on_failover"): int
+        },
+    "pg_hba": [str],
+    "initdb": [Or(str, dict)]
+  },
+  Or(*available_dcs): Case({
+      "consul": {
+          Or("host", "url"): Case({
+              "host": validate_host_port,
+              "url": str})
+          },
+      "etcd": {
+          Or("host", "hosts", "srv", "url", "proxy"): Case({
+              "host": validate_host_port,
+              "hosts": Or(comma_separated_host_port, [validate_host_port]),
+              "srv": str,
+              "url": str,
+              "proxy": str})
+         },
+      "exhibitor": {
+          "hosts": [str],
+          "port": lambda i: assert_(int(i) <= 65535),
+          Optional("pool_interval"): int
+          },
+      "zookeeper": {
+          "hosts": Or(comma_separated_host_port, [validate_host_port]),
+          },
+      "kubernetes": {
+          "labels": {},
+          Optional("namespace"): str,
+          Optional("scope_label"): str,
+          Optional("role_label"): str,
+          Optional("use_endpoints"): bool,
+          Optional("pod_ip"): Or(is_ipv4_address, is_ipv6_address),
+          Optional("ports"): [{"name": str, "port": int}],
+          },
+      }),
+  "postgresql": {
+    "listen": validate_host_port_listen_multiple_hosts,
+    "connect_address": validate_connect_address,
+    "authentication": {
+      "replication": userattributes,
+      "superuser": userattributes,
+      "rewind":  userattributes
+    },
+    "data_dir": validate_data_dir,
+    Optional("bin_dir"): Directory(contains_executable=["pg_ctl", "initdb", "pg_controldata", "pg_basebackup",
+                                                        "postgres", "pg_isready"]),
+    Optional("parameters"): {
+      Optional("unix_socket_directories"): lambda s: assert_(all([isinstance(s, string_types), len(s)]))
+    },
+    Optional("pg_hba"): [str],
+    Optional("pg_ident"): [str],
+    Optional("pg_ctl_timeout"): int,
+    Optional("use_pg_rewind"): bool
+  },
+  Optional("watchdog"): {
+    Optional("mode"): lambda m: assert_(m in ["off", "automatic", "required"]),
+    Optional("device"): str
+  },
+  Optional("tags"): {
+    Optional("nofailover"): bool,
+    Optional("clonefrom"): bool,
+    Optional("noloadbalance"): bool,
+    Optional("replicatefrom"): str,
+    Optional("nosync"): bool
+  }
+})

patroni/version.py

@@ -1 +1 @@
-__version__ = '1.6.0'
+__version__ = '2.0.0'

patroni/watchdog/base.py

@@ -57,7 +57,7 @@ class WatchdogConfig(object):
         return not self == other
 
     def get_impl(self):
-        if self.driver == 'testing':
+        if self.driver == 'testing':  # pragma: no cover
             from patroni.watchdog.linux import TestingWatchdogDevice
             return TestingWatchdogDevice.from_config(self.driver_config)
         elif platform.system() == 'Linux' and self.driver == 'default':

patroni/watchdog/linux.py

@@ -16,11 +16,11 @@ IOC_DIRBITS = 2
 
 # Non-generic platform special cases
 machine = platform.machine()
-if machine in ['mips', 'sparc', 'powerpc', 'ppc64']:
+if machine in ['mips', 'sparc', 'powerpc', 'ppc64']:  # pragma: no cover
     IOC_SIZEBITS = 13
     IOC_DIRBITS = 3
     IOC_NONE, IOC_WRITE, IOC_READ = 1, 2, 4
-elif machine == 'parisc':
+elif machine == 'parisc':  # pragma: no cover
     IOC_WRITE, IOC_READ = 2, 1
 
 IOC_NRSHIFT = 0
@@ -218,7 +218,7 @@ class LinuxWatchdogDevice(WatchdogBase):
         return timeout.value
 
 
-class TestingWatchdogDevice(LinuxWatchdogDevice):
+class TestingWatchdogDevice(LinuxWatchdogDevice):  # pragma: no cover
     """Converts timeout ioctls to regular writes that can be intercepted from a named pipe."""
     timeout = 60
 

patroni_raft_controller.py

@@ -0,0 +1,6 @@
+#!/usr/bin/env python
+from patroni.raft_controller import main
+
+
+if __name__ == '__main__':
+    main()

postgres0.yml

@@ -17,7 +17,25 @@ restapi:
 #   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
 
 etcd:
+  #Provide host to do the initial discovery of the cluster topology:
   host: 127.0.0.1:2379
+  #Or use "hosts" to provide multiple endpoints
+  #Could be a comma separated string:
+  #hosts: host1:port1,host2:port2
+  #or an actual yaml list:
+  #hosts:
+  #- host1:port1
+  #- host2:port2
+  #Once discovery is complete Patroni will use the list of advertised clientURLs
+  #It is possible to change this behavior through by setting:
+  #use_proxies: true
+
+#raft:
+#  data_dir: .
+#  self_addr: 127.0.0.1:2222
+#  partner_addrs:
+#  - 127.0.0.1:2223
+#  - 127.0.0.1:2224
 
 bootstrap:
   # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster
@@ -97,6 +115,8 @@ postgresql:
     # same as KRB5CCNAME used by the GSS
 #   krb_server_keyfile: /var/spool/keytabs/postgres
     unix_socket_directories: '.'
+  # Additional fencing script executed after acquiring the leader lock but before promoting the replica
+  #pre_promote: /path/to/pre_promote.sh
 
 #watchdog:
 #  mode: automatic # Allowed values: off, automatic, required

postgres1.yml

@@ -17,7 +17,25 @@ restapi:
 #   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
 
 etcd:
+  #Provide host to do the initial discovery of the cluster topology:
   host: 127.0.0.1:2379
+  #Or use "hosts" to provide multiple endpoints
+  #Could be a comma separated string:
+  #hosts: host1:port1,host2:port2
+  #or an actual yaml list:
+  #hosts:
+  #- host1:port1
+  #- host2:port2
+  #Once discovery is complete Patroni will use the list of advertised clientURLs
+  #It is possible to change this behavior through by setting:
+  #use_proxies: true
+
+#raft:
+#  data_dir: .
+#  self_addr: 127.0.0.1:2223
+#  partner_addrs:
+#  - 127.0.0.1:2222
+#  - 127.0.0.1:2224
 
 bootstrap:
   # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster
@@ -94,6 +112,9 @@ postgresql:
   basebackup:
       - verbose
       - max-rate: 100M
+  # Additional fencing script executed after acquiring the leader lock but before promoting the replica
+  #pre_promote: /path/to/pre_promote.sh
+
 tags:
     nofailover: false
     noloadbalance: false

postgres2.yml

@@ -17,7 +17,25 @@ restapi:
 #   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
 
 etcd:
+  #Provide host to do the initial discovery of the cluster topology:
   host: 127.0.0.1:2379
+  #Or use "hosts" to provide multiple endpoints
+  #Could be a comma separated string:
+  #hosts: host1:port1,host2:port2
+  #or an actual yaml list:
+  #hosts:
+  #- host1:port1
+  #- host2:port2
+  #Once discovery is complete Patroni will use the list of advertised clientURLs
+  #It is possible to change this behavior through by setting:
+  #use_proxies: true
+
+#raft:
+#  data_dir: .
+#  self_addr: 127.0.0.1:2224
+#  partner_addrs:
+#  - 127.0.0.1:2222
+#  - 127.0.0.1:2223
 
 bootstrap:
   # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster

requirements.txt

@@ -1,15 +1,13 @@
-urllib3>=1.19.1,!=1.21
+urllib3[secure]>=1.19.1,!=1.21
 boto
 PyYAML
-requests
 six >= 1.7
 kazoo>=1.3.1
 python-etcd>=0.4.3,<0.5
-python-consul>=0.7.0
+python-consul>=0.7.1
 click>=4.1
 prettytable>=0.7
-tzlocal
 python-dateutil
+pysyncobj>=0.3.5
 psutil>=2.0.0
 cdiff
-kubernetes>=2.0.0,<=7.0.0,!=4.0.*,!=5.0.*

setup.py

@@ -8,22 +8,12 @@ import inspect
 import os
 import sys
 
-from patroni import check_psycopg2, fatal
+from setuptools import Command, find_packages, setup
-from patroni.version import __version__ as VERSION
-from setuptools.command.test import test as TestCommand
-from setuptools import find_packages, setup
-
-if sys.version_info < (2, 7, 0):
-    fatal('patroni needs to be run with Python 2.7+')
-check_psycopg2()
-del sys.modules['patroni']
-del sys.modules['patroni.version']
 
 __location__ = os.path.join(os.getcwd(), os.path.dirname(inspect.getfile(inspect.currentframe())))
 
 NAME = 'patroni'
 MAIN_PACKAGE = NAME
-SCRIPTS = 'scripts'
 DESCRIPTION = 'PostgreSQL High-Available orchestrator and CLI'
 LICENSE = 'The MIT License'
 URL = 'https://github.com/zalando/patroni'
@@ -32,9 +22,10 @@ AUTHOR_EMAIL = '[email protected], [email protected], alexk
 KEYWORDS = 'etcd governor patroni postgresql postgres ha haproxy confd' +\
     ' zookeeper exhibitor consul streaming replication kubernetes k8s'
 
+EXTRAS_REQUIRE = {'aws': ['boto'], 'etcd': ['python-etcd'], 'etcd3': ['python-etcd'], 'consul': ['python-consul'],
+                  'exhibitor': ['kazoo'], 'zookeeper': ['kazoo'], 'kubernetes': [], 'raft': ['pysyncobj']}
 COVERAGE_XML = True
 COVERAGE_HTML = False
-JUNIT_XML = True
 
 # Add here all kinds of additional classifiers as defined under
 # https://pypi.python.org/pypi?%3Aaction=list_classifiers
@@ -60,82 +51,128 @@ CLASSIFIERS = [
 
 CONSOLE_SCRIPTS = ['patroni = patroni:main',
                    'patronictl = patroni.ctl:ctl',
+                   'patroni_raft_controller = patroni.raft_controller:main',
                    "patroni_wale_restore = patroni.scripts.wale_restore:main",
                    "patroni_aws = patroni.scripts.aws:main"]
 
 
-class PyTest(TestCommand):
+class Flake8(Command):
 
-    user_options = [('cov=', None, 'Run coverage'), ('cov-xml=', None, 'Generate junit xml report'), ('cov-html=',
+    user_options = []
-                    None, 'Generate junit html report'), ('junitxml=', None, 'Generate xml of test results')]
 
     def initialize_options(self):
-        TestCommand.initialize_options(self)
+        from flake8.main import application
+
+        self.flake8 = application.Application()
+        self.flake8.initialize([])
+
+    def finalize_options(self):
+        pass
+
+    def package_files(self):
+        seen_package_directories = ()
+        directories = self.distribution.package_dir or {}
+        empty_directory_exists = "" in directories
+        packages = self.distribution.packages or []
+        for package in packages:
+            if package in directories:
+                package_directory = directories[package]
+            elif empty_directory_exists:
+                package_directory = os.path.join(directories[""], package)
+            else:
+                package_directory = package
+
+            if not package_directory.startswith(seen_package_directories):
+                seen_package_directories += (package_directory + ".",)
+                yield package_directory
+
+    def targets(self):
+        return [package for package in self.package_files()] + ['tests', 'setup.py']
+
+    def run(self):
+        self.flake8.run_checks(self.targets())
+        self.flake8.formatter.start()
+        self.flake8.report_errors()
+        self.flake8.report_statistics()
+        self.flake8.report_benchmarks()
+        self.flake8.formatter.stop()
+        try:
+            self.flake8.exit()
+        except SystemExit as e:
+            # Cause system exit only if exit code is not zero (terminates
+            # other possibly remaining/pending setuptools commands).
+            if e.code:
+                raise
+
+
+class PyTest(Command):
+
+    user_options = [('cov=', None, 'Run coverage'), ('cov-xml=', None, 'Generate junit xml report'),
+                    ('cov-html=', None, 'Generate junit html report')]
+
+    def initialize_options(self):
+        self.cov = []
         self.cov_xml = False
         self.cov_html = False
-        self.junitxml = None
 
     def finalize_options(self):
-        TestCommand.finalize_options(self)
         if self.cov_xml or self.cov_html:
             self.cov = ['--cov', MAIN_PACKAGE, '--cov-report', 'term-missing']
             if self.cov_xml:
                 self.cov.extend(['--cov-report', 'xml'])
             if self.cov_html:
                 self.cov.extend(['--cov-report', 'html'])
-        if self.junitxml is not None:
-            self.junitxml = ['--junitxml', self.junitxml]
 
     def run_tests(self):
         try:
             import pytest
         except Exception:
             raise RuntimeError('py.test is not installed, run: pip install pytest')
-        params = {'args': self.test_args}
-        if self.cov:
-            params['args'] += self.cov
-        if self.junitxml:
-            params['args'] += self.junitxml
-        params['args'] += ['--doctest-modules', MAIN_PACKAGE, '-vv']
 
         import logging
         silence = logging.WARNING
         logging.basicConfig(format='%(asctime)s %(levelname)s: %(message)s', level=os.getenv('LOGLEVEL', silence))
-        params['args'] += ['-s' if logging.getLogger().getEffectiveLevel() < silence else '--capture=fd']
+
-        if not os.getenv('SYSTEMROOT'):
+        args = ['--verbose', 'tests', '--doctest-modules', MAIN_PACKAGE] +\
-            os.environ['SYSTEMROOT'] = '/'
+            ['-s' if logging.getLogger().getEffectiveLevel() < silence else '--capture=fd']
-        errno = pytest.main(**params)
+        if self.cov:
+            args += self.cov
+
+        errno = pytest.main(args=args)
         sys.exit(errno)
 
+    def run(self):
+        from pkg_resources import evaluate_marker
+        requirements = self.distribution.install_requires + ['mock>=2.0.0', 'pytest-cov', 'pytest'] +\
+            [v for k, v in self.distribution.extras_require.items() if not k.startswith(':') or evaluate_marker(k[1:])]
+        self.distribution.fetch_build_eggs(requirements)
+        self.run_tests()
+
 
 def read(fname):
     with open(os.path.join(__location__, fname)) as fd:
         return fd.read()
 
 
-def setup_package():
+def setup_package(version):
     # Assemble additional setup commands
-    cmdclass = {'test': PyTest}
+    cmdclass = {'test': PyTest, 'flake8': Flake8}
 
     install_requires = []
-    extras_require = {'aws': ['boto'], 'etcd': ['python-etcd'], 'consul': ['python-consul'],
-                      'exhibitor': ['kazoo'], 'zookeeper': ['kazoo'], 'kubernetes': ['kubernetes']}
 
     for r in read('requirements.txt').split('\n'):
         r = r.strip()
         if r == '':
             continue
         extra = False
-        for e, v in extras_require.items():
+        for e, v in EXTRAS_REQUIRE.items():
-            if r.startswith(v[0]):
+            if v and r.startswith(v[0]):
-                extras_require[e] = [r]
+                EXTRAS_REQUIRE[e] = [r]
                 extra = True
         if not extra:
             install_requires.append(r)
 
-    command_options = {'test': {'test_suite': ('setup.py', 'tests')}}
+    command_options = {'test': {}}
-    if JUNIT_XML:
-        command_options['test']['junitxml'] = 'setup.py', 'junit.xml'
     if COVERAGE_XML:
         command_options['test']['cov_xml'] = 'setup.py', True
     if COVERAGE_HTML:
@@ -143,7 +180,7 @@ def setup_package():
 
     setup(
         name=NAME,
-        version=VERSION,
+        version=version,
         url=URL,
         author=AUTHOR,
         author_email=AUTHOR_EMAIL,
@@ -152,17 +189,28 @@ def setup_package():
         keywords=KEYWORDS,
         long_description=read('README.rst'),
         classifiers=CLASSIFIERS,
-        test_suite='tests',
         packages=find_packages(exclude=['tests', 'tests.*']),
         package_data={MAIN_PACKAGE: ["*.json"]},
+        python_requires='>=2.7',
         install_requires=install_requires,
-        extras_require=extras_require,
+        extras_require=EXTRAS_REQUIRE,
+        setup_requires='flake8',
         cmdclass=cmdclass,
-        tests_require=['flake8', 'mock>=2.0.0', 'pytest-cov', 'pytest'],
         command_options=command_options,
         entry_points={'console_scripts': CONSOLE_SCRIPTS},
     )
 
 
 if __name__ == '__main__':
-    setup_package()
+    old_modules = sys.modules.copy()
+    try:
+        from patroni import check_psycopg2, fatal, __version__
+    finally:
+        sys.modules.clear()
+        sys.modules.update(old_modules)
+
+    if sys.version_info < (2, 7, 0):
+        fatal('Patroni needs to be run with Python 2.7+')
+    check_psycopg2()
+
+    setup_package(__version__)

tests/__init__.py

@@ -1,14 +1,11 @@
-import datetime
-import json
 import os
 import shutil
 import unittest
 
 from mock import Mock, patch
-from tempfile import gettempdir
 
 import psycopg2
-import requests
+import urllib3
 
 from patroni.dcs import Leader, Member
 from patroni.postgresql import Postgresql
@@ -25,19 +22,12 @@ class MockResponse(object):
     def __init__(self, status_code=200):
         self.status_code = status_code
         self.content = '{}'
-        self.ok = True
+        self.reason = 'Not Found'
-
-    def json(self):
-        return json.loads(self.content)
 
     @property
     def data(self):
         return self.content.encode('utf-8')
 
-    @property
-    def text(self):
-        return self.content
-
     @property
     def status(self):
         return self.status_code
@@ -46,13 +36,17 @@ class MockResponse(object):
     def getheader(*args):
         return ''
 
+    @staticmethod
+    def getheaders():
+        return {'content-type': 'json'}
+
 
 def requests_get(url, **kwargs):
     members = '[{"id":14855829450254237642,"peerURLs":["http://localhost:2380","http://localhost:7001"],' +\
               '"name":"default","clientURLs":["http://localhost:2379","http://localhost:4001"]}]'
     response = MockResponse()
     if url.startswith('http://local'):
-        raise requests.exceptions.RequestException()
+        raise urllib3.exceptions.HTTPError()
     elif ':8011/patroni' in url:
         response.content = '{"role": "replica", "xlog": {"received_location": 0}, "tags": {}}'
     elif url.endswith('/members'):
@@ -63,11 +57,9 @@ def requests_get(url, **kwargs):
         data = kwargs.get('data', '')
         if ' false}' in data:
             response.status_code = 503
-            response.ok = False
             response.content = 'restarting after failure already in progress'
     else:
         response.status_code = 404
-        response.ok = False
     return response
 
 
@@ -78,6 +70,7 @@ class MockPostmaster(object):
         self.wait_for_user_backends_to_close = Mock()
         self.signal_stop = Mock(return_value=None)
         self.wait = Mock()
+        self.signal_kill = Mock(return_value=False)
 
 
 class MockCursor(object):
@@ -87,6 +80,7 @@ class MockCursor(object):
         self.closed = False
         self.rowcount = 0
         self.results = []
+        self.description = [Mock()]
 
     def execute(self, sql, *params):
         if sql.startswith('blabla'):
@@ -98,27 +92,25 @@ class MockCursor(object):
         elif sql.startswith('SELECT slot_name'):
             self.results = [('blabla', 'physical'), ('foobar', 'physical'), ('ls', 'logical', 'a', 'b')]
         elif sql.startswith('SELECT CASE WHEN pg_catalog.pg_is_in_recovery()'):
-            self.results = [(1, 2)]
+            self.results = [(1, 2, 1, 0, False, 1, 1, None, None)]
         elif sql.startswith('SELECT pg_catalog.pg_is_in_recovery()'):
             self.results = [(False, 2)]
-        elif sql.startswith('WITH replication_info AS ('):
+        elif sql.startswith('SELECT pg_catalog.to_char'):
             replication_info = '[{"application_name":"walreceiver","client_addr":"1.2.3.4",' +\
                                '"state":"streaming","sync_state":"async","sync_priority":0}]'
-            self.results = [('', 0, '', '', '', '', False, replication_info)]
+            self.results = [('', 0, '', 0, '', '', False, replication_info)]
         elif sql.startswith('SELECT name, setting'):
             self.results = [('wal_segment_size', '2048', '8kB', 'integer', 'internal'),
+                            ('wal_block_size', '8192', None, 'integer', 'internal'),
+                            ('shared_buffers', '16384', '8kB', 'integer', 'postmaster'),
+                            ('wal_buffers', '-1', '8kB', 'integer', 'postmaster'),
                             ('search_path', 'public', None, 'string', 'user'),
                             ('port', '5433', None, 'integer', 'postmaster'),
                             ('listen_addresses', '*', None, 'string', 'postmaster'),
                             ('autovacuum', 'on', None, 'bool', 'sighup'),
                             ('unix_socket_directories', '/tmp', None, 'string', 'postmaster')]
         elif sql.startswith('IDENTIFY_SYSTEM'):
-            self.results = [('1', 2, '0/402EEC0', '')]
+            self.results = [('1', 3, '0/402EEC0', '')]
-        elif sql.startswith('SELECT isdir, modification'):
-            self.results = [(False, datetime.datetime.now())]
-        elif sql.startswith('SELECT pg_catalog.pg_read_file'):
-            self.results = [('1\t0/40159C0\tno recovery target specified\n\n'
-                             '2\t1/40159C0\tno recovery target specified\n',)]
         elif sql.startswith('TIMELINE_HISTORY '):
             self.results = [('', b'x\t0/40159C0\tno recovery target specified\n\n'
                                  b'1\t0/40159C0\tno recovery target specified\n\n'
@@ -173,17 +165,22 @@ class PostgresInit(unittest.TestCase):
                    'search_path': 'public', 'hot_standby': 'on', 'max_wal_senders': 5,
                    'wal_keep_segments': 8, 'wal_log_hints': 'on', 'max_locks_per_transaction': 64,
                    'max_worker_processes': 8, 'max_connections': 100, 'max_prepared_transactions': 0,
-                   'track_commit_timestamp': 'off', 'unix_socket_directories': '/tmp', 'trigger_file': 'bla'}
+                   'track_commit_timestamp': 'off', 'unix_socket_directories': '/tmp',
+                   'trigger_file': 'bla', 'stats_temp_directory': '/tmp', 'zero_damaged_pages': '',
+                   'force_parallel_mode': '1', 'constraint_exclusion': '',
+                   'max_stack_depth': 'Z', 'vacuum_cost_limit': -1, 'vacuum_cost_delay': 200}
 
     @patch('psycopg2.connect', psycopg2_connect)
+    @patch('patroni.postgresql.CallbackExecutor', Mock())
     @patch.object(ConfigHandler, 'write_postgresql_conf', Mock())
     @patch.object(ConfigHandler, 'replace_pg_hba', Mock())
     @patch.object(ConfigHandler, 'replace_pg_ident', Mock())
+    @patch.object(Postgresql, 'get_postgres_role_from_data_directory', Mock(return_value='master'))
     def setUp(self):
-        data_dir = 'data/test0'
+        data_dir = os.path.join('data', 'test0')
         self.p = Postgresql({'name': 'postgresql0', 'scope': 'batman', 'data_dir': data_dir,
                              'config_dir': data_dir, 'retry_timeout': 10,
-                             'krbsrvname': 'postgres', 'pgpass': os.path.join(gettempdir(), 'pgpass0'),
+                             'krbsrvname': 'postgres', 'pgpass': os.path.join(data_dir, 'pgpass0'),
                              'listen': '127.0.0.2, 127.0.0.3:5432', 'connect_address': '127.0.0.2:5432',
                              'authentication': {'superuser': {'username': 'foo', 'password': 'test'},
                                                 'replication': {'username': '', 'password': 'rep-pass'}},

tests/test_api.py

@@ -12,6 +12,7 @@ from patroni.utils import tzutc
 from six import BytesIO as IO
 from six.moves import BaseHTTPServer
 from . import psycopg2_connect, MockCursor
+from .test_ha import get_cluster_initialized_without_leader
 
 
 future_restart_time = datetime.datetime.now(tzutc) + datetime.timedelta(days=5)
@@ -29,6 +30,8 @@ class MockPostgresql(object):
     pending_restart = True
     wal_name = 'wal'
     lsn_name = 'lsn'
+    POSTMASTER_START_TIME = 'pg_catalog.to_char(pg_catalog.pg_postmaster_start_time'
+    TL_LSN = 'CASE WHEN pg_catalog.pg_is_in_recovery()'
 
     @staticmethod
     def connection():
@@ -145,7 +148,8 @@ class MockRestApiServer(RestApiServer):
         self.serve_forever = Mock()
         MockRestApiServer._BaseServer__is_shut_down = Mock()
         MockRestApiServer._BaseServer__shutdown_request = True
-        config = config or {'listen': '127.0.0.1:8008', 'auth': 'test:test', 'certfile': 'dumb'}
+        config = config or {'listen': '127.0.0.1:8008', 'auth': 'test:test', 'certfile': 'dumb', 'verify_client': 'a',
+                            'http_extra_headers': {'foo': 'bar'}, 'https_extra_headers': {'foo': 'sbar'}}
         super(MockRestApiServer, self).__init__(MockPatroni(), config)
         Handler(MockRequest(request), ('0.0.0.0', 8080), self)
 
@@ -158,7 +162,12 @@ class TestRestApiHandler(unittest.TestCase):
     _authorization = '\nAuthorization: Basic dGVzdDp0ZXN0'
 
     def test_do_GET(self):
+        MockPatroni.dcs.cluster.last_leader_operation = 20
         MockRestApiServer(RestApiHandler, 'GET /replica')
+        MockRestApiServer(RestApiHandler, 'GET /replica?lag=1M')
+        MockRestApiServer(RestApiHandler, 'GET /replica?lag=10MB')
+        MockRestApiServer(RestApiHandler, 'GET /replica?lag=10485760')
+        MockRestApiServer(RestApiHandler, 'GET /read-only')
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={})):
             MockRestApiServer(RestApiHandler, 'GET /replica')
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'master'})):
@@ -166,15 +175,17 @@ class TestRestApiHandler(unittest.TestCase):
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'state': 'running'})):
             MockRestApiServer(RestApiHandler, 'GET /health')
         MockRestApiServer(RestApiHandler, 'GET /master')
-        MockPatroni.dcs.cluster.sync.sync_standby = MockPostgresql.name
+        MockPatroni.dcs.cluster.sync.members = [MockPostgresql.name]
         MockPatroni.dcs.cluster.is_synchronous_mode = Mock(return_value=True)
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'replica'})):
             MockRestApiServer(RestApiHandler, 'GET /synchronous')
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'replica'})):
-            MockPatroni.dcs.cluster.sync.sync_standby = ''
+            MockPatroni.dcs.cluster.sync.members = []
             MockRestApiServer(RestApiHandler, 'GET /asynchronous')
-        MockPatroni.ha.is_leader = Mock(return_value=True)
+        with patch.object(MockHa, 'is_leader', Mock(return_value=True)):
             MockRestApiServer(RestApiHandler, 'GET /replica')
+            with patch.object(MockHa, 'is_standby_cluster', Mock(return_value=True)):
+                MockRestApiServer(RestApiHandler, 'GET /standby_leader')
         MockPatroni.dcs.cluster = None
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'master'})):
             MockRestApiServer(RestApiHandler, 'GET /master')
@@ -189,6 +200,16 @@ class TestRestApiHandler(unittest.TestCase):
     def test_do_OPTIONS(self):
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'OPTIONS / HTTP/1.0'))
 
+    def test_do_GET_liveness(self):
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /liveness HTTP/1.0'))
+
+    def test_do_GET_readiness(self):
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /readiness HTTP/1.0'))
+        with patch.object(MockHa, 'is_leader', Mock(return_value=True)):
+            self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /readiness HTTP/1.0'))
+        with patch.object(MockPostgresql, 'state', PropertyMock(return_value='stopped')):
+            self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /readiness HTTP/1.0'))
+
     @patch.object(MockPostgresql, 'state', PropertyMock(return_value='stopped'))
     def test_do_GET_patroni(self):
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /patroni'))
@@ -197,6 +218,17 @@ class TestRestApiHandler(unittest.TestCase):
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'POST /restart HTTP/1.0'))
         MockRestApiServer(RestApiHandler, 'POST /restart HTTP/1.0\nAuthorization:')
 
+    @patch.object(MockPatroni, 'dcs')
+    def test_do_GET_cluster(self, mock_dcs):
+        mock_dcs.get_cluster.return_value = get_cluster_initialized_without_leader()
+        mock_dcs.get_cluster.return_value.members[1].data['xlog_location'] = 11
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /cluster'))
+
+    @patch.object(MockPatroni, 'dcs')
+    def test_do_GET_history(self, mock_dcs):
+        mock_dcs.cluster = get_cluster_initialized_without_leader()
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /history'))
+
     @patch.object(MockPatroni, 'dcs')
     def test_do_GET_config(self, mock_dcs):
         mock_dcs.cluster.config.data = {}
@@ -219,6 +251,8 @@ class TestRestApiHandler(unittest.TestCase):
         MockRestApiServer(RestApiHandler, request)
         mock_dcs.set_config_value.return_value = False
         MockRestApiServer(RestApiHandler, request)
+        mock_dcs.get_cluster.return_value.config = None
+        MockRestApiServer(RestApiHandler, request)
 
     @patch.object(MockPatroni, 'dcs')
     def test_do_PUT_config(self, mock_dcs):
@@ -233,11 +267,8 @@ class TestRestApiHandler(unittest.TestCase):
         mock_dcs.get_cluster.return_value.config = ClusterConfig.from_node(1, config)
         MockRestApiServer(RestApiHandler, request)
 
-    @patch.object(MockPatroni, 'sighup_handler', Mock(side_effect=Exception))
+    @patch.object(MockPatroni, 'sighup_handler', Mock())
     def test_do_POST_reload(self):
-        with patch.object(MockPatroni, 'config') as mock_config:
-            mock_config.reload_local_configuration.return_value = False
-            MockRestApiServer(RestApiHandler, 'POST /reload HTTP/1.0' + self._authorization)
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'POST /reload HTTP/1.0' + self._authorization))
 
     @patch.object(MockPatroni, 'dcs')
@@ -297,6 +328,15 @@ class TestRestApiHandler(unittest.TestCase):
                 request = 'DELETE /restart HTTP/1.0' + self._authorization
                 self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
 
+    @patch.object(MockPatroni, 'dcs')
+    def test_do_DELETE_switchover(self, mock_dcs):
+        request = 'DELETE /switchover HTTP/1.0' + self._authorization
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+        mock_dcs.manual_failover.return_value = False
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+        mock_dcs.get_cluster.return_value.failover = None
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+
     @patch.object(MockPatroni, 'dcs')
     def test_do_POST_reinitialize(self, mock_dcs):
         cluster = mock_dcs.get_cluster.return_value
@@ -403,22 +443,48 @@ class TestRestApiHandler(unittest.TestCase):
         MockRestApiServer(RestApiHandler, post + '37\n\n{"candidate":"2","scheduled_at": "1"}')
 
 
+class TestRestApiServer(unittest.TestCase):
+
     @patch('ssl.SSLContext.load_cert_chain', Mock())
     @patch('ssl.SSLContext.wrap_socket', Mock(return_value=0))
     @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
-class TestRestApiServer(unittest.TestCase):
+    def setUp(self):
+        self.srv = MockRestApiServer(Mock(), '', {'listen': '*:8008', 'certfile': 'a', 'verify_client': 'required'})
 
+    @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
     def test_reload_config(self):
         bad_config = {'listen': 'foo'}
         self.assertRaises(ValueError, MockRestApiServer, None, '', bad_config)
-        srv = MockRestApiServer(lambda a1, a2, a3: None, '')
+        self.assertRaises(ValueError, self.srv.reload_config, bad_config)
-        self.assertRaises(ValueError, srv.reload_config, bad_config)
+        self.assertRaises(ValueError, self.srv.reload_config, {})
-        self.assertRaises(ValueError, srv.reload_config, {})
         with patch.object(socket.socket, 'setsockopt', Mock(side_effect=socket.error)):
-            srv.reload_config({'listen': ':8008'})
+            self.srv.reload_config({'listen': ':8008'})
+
+    def test_check_auth(self):
+        mock_rh = Mock()
+        mock_rh.request.getpeercert.return_value = None
+        self.assertIsNot(self.srv.check_auth(mock_rh), True)
 
     def test_handle_error(self):
         try:
             raise Exception()
         except Exception:
             self.assertIsNone(MockRestApiServer.handle_error(None, ('127.0.0.1', 55555)))
+
+    @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock(side_effect=socket.error))
+    def test_socket_error(self):
+        self.assertRaises(socket.error, MockRestApiServer, Mock(), '', {'listen': '*:8008'})
+
+    @patch.object(MockRestApiServer, 'finish_request', Mock())
+    def test_process_request_thread(self):
+        mock_socket = Mock()
+        self.srv.process_request_thread((mock_socket, 1), '2')
+        mock_socket.context.wrap_socket.side_effect = socket.error
+        self.srv.process_request_thread((mock_socket, 1), '2')
+
+    @patch.object(socket.socket, 'accept')
+    def test_get_request(self, mock_accept):
+        newsock = Mock()
+        mock_accept.return_value = (newsock, '2')
+        self.srv.socket = Mock()
+        self.assertEqual(self.srv.get_request(), ((self.srv.socket, newsock), '2'))

tests/test_aws.py

@@ -1,11 +1,11 @@
 import boto.ec2
 import sys
 import unittest
+import urllib3
 
 from mock import Mock, patch
 from collections import namedtuple
 from patroni.scripts.aws import AWSConnection, main as _main
-from requests.exceptions import RequestException
 
 
 class MockEc2Connection(object):
@@ -22,28 +22,11 @@ class MockEc2Connection(object):
         return True
 
 
-class MockResponse(object):
-    ok = True
-
-    def __init__(self, content):
-        self.content = content
-
-    def json(self):
-        return self.content
-
-
-def requests_get(url, **kwargs):
-    if url.split('/')[-1] == 'document':
-        result = {"instanceId": "012345", "region": "eu-west-1"}
-    else:
-        result = 'foo'
-    return MockResponse(result)
-
-
 @patch('boto.ec2.connect_to_region', Mock(return_value=MockEc2Connection()))
 class TestAWSConnection(unittest.TestCase):
 
-    @patch('requests.get', requests_get)
+    @patch('patroni.scripts.aws.requests_get', Mock(return_value=urllib3.HTTPResponse(
+        status=200, body=b'{"instanceId": "012345", "region": "eu-west-1"}')))
     def setUp(self):
         self.conn = AWSConnection('test')
 
@@ -53,17 +36,18 @@ class TestAWSConnection(unittest.TestCase):
             self.conn._retry.max_tries = 1
             self.assertFalse(self.conn.on_role_change('master'))
 
-    @patch('requests.get', Mock(side_effect=RequestException('foo')))
+    @patch('patroni.scripts.aws.requests_get', Mock(side_effect=Exception('foo')))
     def test_non_aws(self):
         conn = AWSConnection('test')
         self.assertFalse(conn.on_role_change("master"))
 
-    @patch('requests.get', Mock(return_value=MockResponse('foo')))
+    @patch('patroni.scripts.aws.requests_get', Mock(return_value=urllib3.HTTPResponse(status=200, body=b'foo')))
     def test_aws_bizare_response(self):
         conn = AWSConnection('test')
         self.assertFalse(conn.aws_available())
 
-    @patch('requests.get', requests_get)
+    @patch('patroni.scripts.aws.requests_get', Mock(return_value=urllib3.HTTPResponse(
+        status=200, body=b'{"instanceId": "012345", "region": "eu-west-1"}')))
     @patch('sys.exit', Mock())
     def test_main(self):
         self.assertIsNone(_main())

tests/test_bootstrap.py

@@ -16,6 +16,7 @@ from . import psycopg2_connect, BaseTestPostgresql
 @patch('os.rename', Mock())
 class TestBootstrap(BaseTestPostgresql):
 
+    @patch('patroni.postgresql.CallbackExecutor', Mock())
     def setUp(self):
         super(TestBootstrap, self).setUp()
         self.b = self.p.bootstrap
@@ -101,6 +102,9 @@ class TestBootstrap(BaseTestPostgresql):
     @patch.object(CancellableSubprocess, 'call', Mock())
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
     @patch.object(Postgresql, 'data_directory_empty', Mock(return_value=False))
+    @patch.object(Postgresql, 'controldata', Mock(return_value={'max_connections setting': 100,
+                                                                'max_prepared_xacts setting': 0,
+                                                                'max_locks_per_xact setting': 64}))
     def test_bootstrap(self):
         with patch('subprocess.call', Mock(return_value=1)):
             self.assertFalse(self.b.bootstrap({}))
@@ -108,7 +112,8 @@ class TestBootstrap(BaseTestPostgresql):
         config = {'users': {'replicator': {'password': 'rep-pass', 'options': ['replication']}}}
 
         with patch.object(Postgresql, 'is_running', Mock(return_value=False)),\
-                patch('multiprocessing.Process', Mock(side_effect=Exception)):
+                patch('multiprocessing.Process', Mock(side_effect=Exception)),\
+                patch('multiprocessing.get_context', Mock(side_effect=Exception), create=True):
             self.assertRaises(Exception, self.b.bootstrap, config)
         with open(os.path.join(self.p.data_dir, 'pg_hba.conf')) as f:
             lines = f.readlines()
@@ -126,6 +131,7 @@ class TestBootstrap(BaseTestPostgresql):
 
     @patch.object(CancellableSubprocess, 'call')
     @patch.object(Postgresql, 'get_major_version', Mock(return_value=90600))
+    @patch.object(Postgresql, 'controldata',  Mock(return_value={'Database cluster state': 'in production'}))
     def test_custom_bootstrap(self, mock_cancellable_subprocess_call):
         self.p.config._config.pop('pg_hba')
         config = {'method': 'foo', 'foo': {'command': 'bar'}}
@@ -135,6 +141,7 @@ class TestBootstrap(BaseTestPostgresql):
 
         mock_cancellable_subprocess_call.return_value = 0
         with patch('multiprocessing.Process', Mock(side_effect=Exception("42"))),\
+                patch('multiprocessing.get_context', Mock(side_effect=Exception("42")), create=True),\
                 patch('os.path.isfile', Mock(return_value=True)),\
                 patch('os.unlink', Mock()),\
                 patch.object(ConfigHandler, 'save_configuration_files', Mock()),\
@@ -202,13 +209,13 @@ class TestBootstrap(BaseTestPostgresql):
         mock_cancellable_subprocess_call.assert_called()
         args, kwargs = mock_cancellable_subprocess_call.call_args
         self.assertTrue('PGPASSFILE' in kwargs['env'])
-        self.assertEqual(args[0], ['/bin/false', 'postgres://127.0.0.2:5432/postgres'])
+        self.assertEqual(args[0], ['/bin/false', 'dbname=postgres host=127.0.0.2 port=5432'])
 
         mock_cancellable_subprocess_call.reset_mock()
         self.p.config._local_address.pop('host')
         self.assertTrue(self.b.call_post_bootstrap({'post_init': '/bin/false'}))
         mock_cancellable_subprocess_call.assert_called()
-        self.assertEqual(mock_cancellable_subprocess_call.call_args[0][0], ['/bin/false', 'postgres://:5432/postgres'])
+        self.assertEqual(mock_cancellable_subprocess_call.call_args[0][0], ['/bin/false', 'dbname=postgres port=5432'])
 
         mock_cancellable_subprocess_call.side_effect = OSError
         self.assertFalse(self.b.call_post_bootstrap({'post_init': '/bin/false'}))

tests/test_callback_executor.py

@@ -1,3 +1,4 @@
+import psutil
 import unittest
 
 from mock import Mock, patch
@@ -6,22 +7,28 @@ from patroni.postgresql.callback_executor import CallbackExecutor
 
 class TestCallbackExecutor(unittest.TestCase):
 
-    @patch('subprocess.Popen')
+    @patch('psutil.Popen')
     def test_callback_executor(self, mock_popen):
-        mock_popen.return_value.wait.side_effect = Exception
+        mock_popen.return_value.children.return_value = []
-        mock_popen.return_value.poll.return_value = None
+        mock_popen.return_value.is_running.return_value = True
 
         ce = CallbackExecutor()
+        ce._kill_children = Mock(side_effect=Exception)
         self.assertIsNone(ce.call([]))
         ce.join()
 
         self.assertIsNone(ce.call([]))
 
-        mock_popen.return_value.kill.side_effect = OSError
+        mock_popen.return_value.kill.side_effect = psutil.AccessDenied()
+        self.assertIsNone(ce.call([]))
+
+        ce._process_children = []
+        mock_popen.return_value.children.side_effect = psutil.Error()
+        mock_popen.return_value.kill.side_effect = psutil.NoSuchProcess(123)
         self.assertIsNone(ce.call([]))
 
         mock_popen.side_effect = Exception
         ce = CallbackExecutor()
-        ce._callback_event.wait = Mock(side_effect=[None, Exception])
+        ce._condition.wait = Mock(side_effect=[None, Exception])
         self.assertIsNone(ce.call([]))
         ce.join()

tests/test_cancellable.py

@@ -1,6 +1,7 @@
+import psutil
 import unittest
 
-from mock import Mock, PropertyMock, patch
+from mock import Mock, patch
 from patroni.exceptions import PostgresException
 from patroni.postgresql.cancellable import CancellableSubprocess
 
@@ -12,12 +13,22 @@ class TestCancellableSubprocess(unittest.TestCase):
 
     def test_call(self):
         self.c.cancel()
-        self.assertRaises(PostgresException, self.c.call, communicate_input=None)
+        self.assertRaises(PostgresException, self.c.call)
+
+    def test__kill_children(self):
+        self.c._process_children = [Mock()]
+        self.c._kill_children()
+        self.c._process_children[0].kill.side_effect = psutil.AccessDenied()
+        self.c._kill_children()
+        self.c._process_children[0].kill.side_effect = psutil.NoSuchProcess(123)
+        self.c._kill_children()
 
     @patch('patroni.postgresql.cancellable.polling_loop', Mock(return_value=[0, 0]))
     def test_cancel(self):
         self.c._process = Mock()
-        self.c._process.returncode = None
+        self.c._process.is_running.return_value = True
+        self.c._process.children.side_effect = psutil.Error()
+        self.c._process.suspend.side_effect = psutil.Error()
         self.c.cancel()
-        type(self.c._process).returncode = PropertyMock(side_effect=[None, -15])
+        self.c._process.is_running.side_effect = [True, False]
         self.c.cancel()

tests/test_config.py

@@ -1,9 +1,10 @@
 import os
 import sys
 import unittest
+import io
 
 from mock import MagicMock, Mock, patch
-from patroni.config import Config
+from patroni.config import Config, ConfigParseError
 from six.moves import builtins
 
 
@@ -15,10 +16,7 @@ class TestConfig(unittest.TestCase):
     def setUp(self):
         sys.argv = ['patroni.py']
         os.environ[Config.PATRONI_CONFIG_VARIABLE] = 'restapi: {}\npostgresql: {data_dir: foo}'
-        self.config = Config()
+        self.config = Config(None)
-
-    def test_no_config(self):
-        self.assertRaises(SystemExit, Config)
 
     def test_set_dynamic_configuration(self):
         with patch.object(Config, '_build_effective_configuration', Mock(side_effect=Exception)):
@@ -58,6 +56,7 @@ class TestConfig(unittest.TestCase):
             'PATRONI_ZOOKEEPER_HOSTS': "'host1:2181','host2:2181'",
             'PATRONI_EXHIBITOR_HOSTS': 'host1,host2',
             'PATRONI_EXHIBITOR_PORT': '8181',
+            'PATRONI_RAFT_PARTNER_ADDRS': "'host1:1234','host2:1234'",
             'PATRONI_foo_HOSTS': '[host1,host2',  # Exception in parse_list
             'PATRONI_SUPERUSER_USERNAME': 'postgres',
             'PATRONI_SUPERUSER_PASSWORD': 'zalando',
@@ -66,12 +65,10 @@ class TestConfig(unittest.TestCase):
             'PATRONI_admin_PASSWORD': 'admin',
             'PATRONI_admin_OPTIONS': 'createrole,createdb'
         })
-        sys.argv = ['patroni.py', 'postgres0.yml']
+        config = Config('postgres0.yml')
-        config = Config()
         with patch.object(Config, '_load_config_file', Mock(return_value={'restapi': {}})):
             with patch.object(Config, '_build_effective_configuration', Mock(side_effect=Exception)):
-                self.assertRaises(Exception, config.reload_local_configuration, True)
+                config.reload_local_configuration()
-            self.assertTrue(config.reload_local_configuration(True))
             self.assertTrue(config.reload_local_configuration())
             self.assertIsNone(config.reload_local_configuration())
 
@@ -99,3 +96,46 @@ class TestConfig(unittest.TestCase):
         self.config.set_dynamic_configuration(dynamic_configuration)
         for name, value in dynamic_configuration['standby_cluster'].items():
             self.assertEqual(self.config['standby_cluster'][name], value)
+
+    @patch('os.path.exists', Mock(return_value=True))
+    @patch('os.path.isfile', Mock(side_effect=lambda fname: fname != 'postgres0'))
+    @patch('os.path.isdir', Mock(return_value=True))
+    @patch('os.listdir', Mock(return_value=['01-specific.yml', '00-base.yml']))
+    def test_configuration_directory(self):
+        def open_mock(fname, *args, **kwargs):
+            if fname.endswith('00-base.yml'):
+                return io.StringIO(
+                    u'''
+                    test: True
+                    test2:
+                      child-1: somestring
+                      child-2: 5
+                      child-3: False
+                    test3: True
+                    test4:
+                     - abc: 3
+                     - abc: 4
+                    ''')
+            elif fname.endswith('01-specific.yml'):
+                return io.StringIO(
+                    u'''
+                    test: False
+                    test2:
+                      child-2: 10
+                      child-3: !!null
+                    test4:
+                     - ab: 5
+                    new-attr: True
+                    ''')
+
+        with patch.object(builtins, 'open', MagicMock(side_effect=open_mock)):
+            config = Config('postgres0')
+            self.assertEqual(config._local_configuration,
+                             {'test': False, 'test2': {'child-1': 'somestring', 'child-2': 10},
+                              'test3': True, 'test4': [{'ab': 5}], 'new-attr': True})
+
+    @patch('os.path.exists', Mock(return_value=True))
+    @patch('os.path.isfile', Mock(return_value=False))
+    @patch('os.path.isdir', Mock(return_value=False))
+    def test_invalid_path(self):
+        self.assertRaises(ConfigParseError, Config, 'postgres0')

tests/test_consul.py

@@ -122,6 +122,8 @@ class TestConsul(unittest.TestCase):
         self.c.refresh_session = Mock(return_value=True)
         for _ in range(0, 4):
             self.c.touch_member({'balbla': 'blabla'})
+        self.c.refresh_session = Mock(side_effect=ConsulError('foo'))
+        self.assertFalse(self.c.touch_member({'balbla': 'blabla'}))
 
     @patch.object(consul.Consul.KV, 'put', Mock(side_effect=InvalidSession))
     def test_take_leader(self):

tests/test_ctl.py

@@ -1,50 +1,53 @@
 import etcd
 import os
-import requests
-import sys
 import unittest
 
 from click.testing import CliRunner
 from datetime import datetime, timedelta
 from mock import patch, Mock
-from patroni.ctl import ctl, store_config, load_config, output_members, request_patroni, get_dcs, parse_dcs, \
+from patroni.ctl import ctl, store_config, load_config, output_members, get_dcs, parse_dcs, \
     get_all_members, get_any_member, get_cursor, query_member, configure, PatroniCtlException, apply_config_changes, \
-    format_config_for_editing, show_diff, invoke_editor, format_pg_version, find_executable
+    format_config_for_editing, show_diff, invoke_editor, format_pg_version, find_executable, CONFIG_FILE_PATH
-from patroni.dcs.etcd import Client, Failover
+from patroni.dcs.etcd import AbstractEtcdClientWithFailover, Failover
 from patroni.utils import tzutc
 from psycopg2 import OperationalError
+from urllib3 import PoolManager
 
-from . import MockConnect, MockCursor, MockResponse, psycopg2_connect, requests_get
+from . import MockConnect, MockCursor, MockResponse, psycopg2_connect
 from .test_etcd import etcd_read, socket_getaddrinfo
 from .test_ha import get_cluster_initialized_without_leader, get_cluster_initialized_with_leader, \
     get_cluster_initialized_with_only_leader, get_cluster_not_initialized_without_leader, get_cluster, Member
 
-CONFIG_FILE_PATH = './test-ctl.yaml'
-
 
 def test_rw_config():
     runner = CliRunner()
     with runner.isolated_filesystem():
-        sys.argv = ['patronictl.py', '']
+        load_config(CONFIG_FILE_PATH, None)
-        load_config(CONFIG_FILE_PATH + '/dummy', None)
+        CONFIG_PATH = './test-ctl.yaml'
-        store_config({'etcd': {'host': 'localhost:2379'}}, CONFIG_FILE_PATH + '/dummy')
+        store_config({'etcd': {'host': 'localhost:2379'}}, CONFIG_PATH + '/dummy')
-        load_config(CONFIG_FILE_PATH + '/dummy', '0.0.0.0')
+        load_config(CONFIG_PATH + '/dummy', '0.0.0.0')
-        os.remove(CONFIG_FILE_PATH + '/dummy')
+        os.remove(CONFIG_PATH + '/dummy')
-        os.rmdir(CONFIG_FILE_PATH)
+        os.rmdir(CONFIG_PATH)
 
 
-@patch('patroni.ctl.load_config',
+@patch('patroni.ctl.load_config', Mock(return_value={
-       Mock(return_value={'scope': 'alpha', 'postgresql': {'data_dir': '.', 'parameters': {}, 'retry_timeout': 5},
+    'scope': 'alpha', 'restapi': {'listen': '::', 'certfile': 'a'}, 'etcd': {'host': 'localhost:2379'},
-                          'restapi': {'auth': 'u:p', 'listen': ''}, 'etcd': {'host': 'localhost:2379'}}))
+    'postgresql': {'data_dir': '.', 'pgpass': './pgpass', 'parameters': {}, 'retry_timeout': 5}}))
 class TestCtl(unittest.TestCase):
 
     @patch('socket.getaddrinfo', socket_getaddrinfo)
     def setUp(self):
-        with patch.object(Client, 'machines') as mock_machines:
+        with patch.object(AbstractEtcdClientWithFailover, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
             self.runner = CliRunner()
             self.e = get_dcs({'etcd': {'ttl': 30, 'host': 'ok:2379', 'retry_timeout': 10}}, 'foo')
 
+    def test_load_config(self):
+        runner = CliRunner()
+        with runner.isolated_filesystem():
+            self.assertRaises(PatroniCtlException, load_config, './non-existing-config-file', None)
+            self.assertRaises(PatroniCtlException, load_config, './non-existing-config-file', None)
+
     @patch('psycopg2.connect', psycopg2_connect)
     def test_get_cursor(self):
         self.assertIsNone(get_cursor(get_cluster_initialized_without_leader(), {}, role='master'))
@@ -69,13 +72,12 @@ class TestCtl(unittest.TestCase):
     def test_output_members(self):
         scheduled_at = datetime.now(tzutc) + timedelta(seconds=600)
         cluster = get_cluster_initialized_with_leader(Failover(1, 'foo', 'bar', scheduled_at))
-        self.assertIsNone(output_members(cluster, name='abc', fmt='pretty'))
+        del cluster.members[1].data['conn_url']
-        self.assertIsNone(output_members(cluster, name='abc', fmt='json'))
+        for fmt in ('pretty', 'json', 'yaml', 'tsv', 'topology'):
-        self.assertIsNone(output_members(cluster, name='abc', fmt='yaml'))
+            self.assertIsNone(output_members(cluster, name='abc', fmt=fmt))
-        self.assertIsNone(output_members(cluster, name='abc', fmt='tsv'))
 
     @patch('patroni.ctl.get_dcs')
-    @patch('patroni.ctl.request_patroni', Mock(return_value=MockResponse()))
+    @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
     def test_switchover(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
@@ -125,18 +127,18 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['switchover', 'dummy'], input='dummy')
         assert result.exit_code == 1
 
-        with patch('patroni.ctl.request_patroni', Mock(side_effect=Exception)):
+        with patch.object(PoolManager, 'request', Mock(side_effect=Exception)):
             # Non-responding patroni
             result = self.runner.invoke(ctl, ['switchover', 'dummy'], input='leader\nother\n2300-01-01T12:23:00\ny')
             assert 'falling back to DCS' in result.output
 
-        with patch('patroni.ctl.request_patroni') as mocked:
+        with patch.object(PoolManager, 'request') as mocked:
-            mocked.return_value.status_code = 500
+            mocked.return_value.status = 500
             result = self.runner.invoke(ctl, ['switchover', 'dummy'], input='leader\nother\n\ny')
             assert 'Switchover failed' in result.output
 
-            mocked.return_value.status_code = 501
+            mocked.return_value.status = 501
-            mocked.return_value.text = 'Server does not support this operation'
+            mocked.return_value.data = b'Server does not support this operation'
             result = self.runner.invoke(ctl, ['switchover', 'dummy'], input='leader\nother\n\ny')
             assert 'Switchover failed' in result.output
 
@@ -151,7 +153,7 @@ class TestCtl(unittest.TestCase):
         assert result.exit_code == 1
 
     @patch('patroni.ctl.get_dcs')
-    @patch('patroni.ctl.request_patroni', Mock(return_value=MockResponse()))
+    @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
     def test_failover(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
@@ -159,6 +161,7 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['failover', 'dummy'], input='\n')
         assert 'Failover could be performed only to a specific candidate' in result.output
 
+    @patch('patroni.dcs.dcs_modules', Mock(return_value=['patroni.dcs.dummy', 'patroni.dcs.etcd']))
     def test_get_dcs(self):
         self.assertRaises(PatroniCtlException, get_dcs, {'dummy': {}}, 'dummy')
 
@@ -201,9 +204,6 @@ class TestCtl(unittest.TestCase):
             rows = query_member(None, None, None, 'master', 'SELECT pg_catalog.pg_is_in_recovery()', {})
             self.assertTrue('False' in str(rows))
 
-            rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
-            self.assertEqual(rows, (None, None))
-
             with patch.object(MockCursor, 'execute', Mock(side_effect=OperationalError('bla'))):
                 rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
 
@@ -231,7 +231,7 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['dsn', 'alpha', '--member', 'dummy'])
         assert result.exit_code == 1
 
-    @patch('requests.post')
+    @patch.object(PoolManager, 'request')
     @patch('patroni.ctl.get_dcs')
     def test_reload(self, mock_get_dcs, mock_post):
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
@@ -239,18 +239,19 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['reload', 'alpha'], input='y')
         assert 'Failed: reload for member' in result.output
 
-        mock_post.return_value.status_code = 200
+        mock_post.return_value.status = 200
         result = self.runner.invoke(ctl, ['reload', 'alpha'], input='y')
         assert 'No changes to apply on member' in result.output
 
-        mock_post.return_value.status_code = 202
+        mock_post.return_value.status = 202
         result = self.runner.invoke(ctl, ['reload', 'alpha'], input='y')
         assert 'Reload request received for member' in result.output
 
-    @patch('requests.post', requests_get)
+    @patch.object(PoolManager, 'request')
     @patch('patroni.ctl.get_dcs')
-    def test_restart_reinit(self, mock_get_dcs):
+    def test_restart_reinit(self, mock_get_dcs, mock_post):
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
+        mock_post.return_value.status = 503
         result = self.runner.invoke(ctl, ['restart', 'alpha'], input='now\ny\n')
         assert 'Failed: restart for' in result.output
         assert result.exit_code == 0
@@ -285,10 +286,8 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['restart', 'alpha', '--pending', '--force', '--timeout', '10min'])
         assert result.exit_code == 0
 
-        with patch('requests.delete', Mock(return_value=MockResponse(500))):
         # normal restart, the schedule is actually parsed, but not validated in patronictl
-            result = self.runner.invoke(ctl, ['restart', 'alpha', 'other', '--force',
+        result = self.runner.invoke(ctl, ['restart', 'alpha', 'other', '--force', '--scheduled', '2300-10-01T14:30'])
-                                              '--scheduled', '2300-10-01T14:30'])
         assert 'Failed: flush scheduled restart' in result.output
 
         with patch('patroni.dcs.Cluster.is_paused', Mock(return_value=True)):
@@ -296,47 +295,40 @@ class TestCtl(unittest.TestCase):
                                         ['restart', 'alpha', 'other', '--force', '--scheduled', '2300-10-01T14:30'])
             assert result.exit_code == 1
 
-        with patch('requests.post', Mock(return_value=MockResponse())):
-            # normal restart, the schedule is actually parsed, but not validated in patronictl
-            result = self.runner.invoke(ctl, ['restart', 'alpha', '--pg-version', '42.0.0',
-                                              '--scheduled', '2300-10-01T14:30'], input='y')
-            assert result.exit_code == 0
-
-        with patch('requests.post', Mock(return_value=MockResponse(204))):
-            # get restart with the non-200 return code
-            # normal restart, the schedule is actually parsed, but not validated in patronictl
-            result = self.runner.invoke(ctl, ['restart', 'alpha', '--pg-version', '42.0',
-                                              '--scheduled', '2300-10-01T14:30'], input='y')
-            assert result.exit_code == 0
-
         # force restart with restart already present
-        with patch('patroni.ctl.request_patroni', Mock(return_value=MockResponse(204))):
+        result = self.runner.invoke(ctl, ['restart', 'alpha', 'other', '--force', '--scheduled', '2300-10-01T14:30'])
-            result = self.runner.invoke(ctl, ['restart', 'alpha', 'other', '--force',
+        assert result.exit_code == 0
-                                              '--scheduled', '2300-10-01T14:30'])
+
+        ctl_args = ['restart', 'alpha', '--pg-version', '99.0', '--scheduled', '2300-10-01T14:30']
+        # normal restart, the schedule is actually parsed, but not validated in patronictl
+        mock_post.return_value.status = 200
+        result = self.runner.invoke(ctl, ctl_args, input='y')
         assert result.exit_code == 0
 
-        with patch('requests.post', Mock(return_value=MockResponse(202))):
         # get restart with the non-200 return code
         # normal restart, the schedule is actually parsed, but not validated in patronictl
-            result = self.runner.invoke(
+        mock_post.return_value.status = 204
-                ctl, ['restart', 'alpha', '--pg-version', '99.0.0', '--scheduled', '2300-10-01T14:30'], input='y'
+        result = self.runner.invoke(ctl, ctl_args, input='y')
-            )
+        assert result.exit_code == 0
+
+        # get restart with the non-200 return code
+        # normal restart, the schedule is actually parsed, but not validated in patronictl
+        mock_post.return_value.status = 202
+        result = self.runner.invoke(ctl, ctl_args, input='y')
         assert 'Success: restart scheduled' in result.output
         assert result.exit_code == 0
 
-        with patch('requests.post', Mock(return_value=MockResponse(409))):
         # get restart with the non-200 return code
         # normal restart, the schedule is actually parsed, but not validated in patronictl
-            result = self.runner.invoke(
+        mock_post.return_value.status = 409
-                ctl, ['restart', 'alpha', '--pg-version', '99.0.0', '--scheduled', '2300-10-01T14:30'], input='y'
+        result = self.runner.invoke(ctl, ctl_args, input='y')
-            )
         assert 'Failed: another restart is already' in result.output
         assert result.exit_code == 0
 
     @patch('patroni.ctl.get_dcs')
     def test_remove(self, mock_get_dcs):
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
-        result = self.runner.invoke(ctl, ['remove', 'alpha'], input='alpha\nslave')
+        result = self.runner.invoke(ctl, ['-k', 'remove', 'alpha'], input='alpha\nslave')
         assert 'Please confirm' in result.output
         assert 'You are about to remove all' in result.output
         # Not typing an exact confirmation
@@ -353,17 +345,6 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['remove', 'alpha'], input='alpha\nYes I am aware\nleader')
         assert result.exit_code == 0
 
-    @patch('requests.post', Mock(side_effect=requests.exceptions.ConnectionError('foo')))
-    @patch('click.get_current_context')
-    def test_request_patroni(self, mock_context):
-        member = get_cluster_initialized_with_leader().leader.member
-
-        mock_context.return_value.obj = {'ctl': {'cacert': 'cert.pem'}}
-        self.assertRaises(requests.exceptions.ConnectionError, request_patroni, member, 'post', 'dummy', {})
-
-        mock_context.return_value.obj = {'ctl': {'insecure': True}}
-        self.assertRaises(requests.exceptions.ConnectionError, request_patroni, member, 'post', 'dummy', {})
-
     def test_ctl(self):
         self.runner.invoke(ctl, ['list'])
 
@@ -437,8 +418,38 @@ class TestCtl(unittest.TestCase):
         assert 'Scheduled restart' in result.output
 
     @patch('patroni.ctl.get_dcs')
-    @patch('requests.delete', Mock(return_value=MockResponse()))
+    def test_topology(self, mock_get_dcs):
-    def test_flush(self, mock_get_dcs):
+        mock_get_dcs.return_value = self.e
+        cluster = get_cluster_initialized_with_leader()
+        cascade_member = Member(0, 'cascade', 28, {'conn_url': 'postgres://replicator:[email protected]:5437/postgres',
+                                                   'api_url': 'http://127.0.0.1:8012/patroni',
+                                                   'state': 'running',
+                                                   'tags': {'replicatefrom': 'other'},
+                                                   })
+        cascade_member_wrong_tags = Member(0, 'wrong_cascade', 28,
+                                           {'conn_url': 'postgres://replicator:[email protected]:5438/postgres',
+                                            'api_url': 'http://127.0.0.1:8013/patroni',
+                                            'state': 'running',
+                                            'tags': {'replicatefrom': 'nonexistinghost'},
+                                            })
+        cluster.members.append(cascade_member)
+        cluster.members.append(cascade_member_wrong_tags)
+        mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
+        result = self.runner.invoke(ctl, ['topology', 'dummy'])
+        assert '+\n| leader          | 127.0.0.1:5435 | Leader  |' in result.output
+        assert '|\n| + other         | 127.0.0.1:5436 | Replica |' in result.output
+        assert '|\n|   + cascade     | 127.0.0.1:5437 | Replica |' in result.output
+        assert '|\n| + wrong_cascade | 127.0.0.1:5438 | Replica |' in result.output
+
+        cluster = get_cluster_initialized_without_leader()
+        mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
+        result = self.runner.invoke(ctl, ['topology', 'dummy'])
+        assert '+\n| + leader | 127.0.0.1:5435 | Replica |' in result.output
+        assert '|\n| + other  | 127.0.0.1:5436 | Replica |' in result.output
+
+    @patch('patroni.ctl.get_dcs')
+    @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
+    def test_flush_restart(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
 
@@ -447,26 +458,46 @@ class TestCtl(unittest.TestCase):
 
         result = self.runner.invoke(ctl, ['flush', 'dummy', 'restart', '--force'])
         assert 'Success: flush scheduled restart' in result.output
-        with patch.object(requests, 'delete', return_value=MockResponse(404)):
+        with patch.object(PoolManager, 'request', return_value=MockResponse(404)):
             result = self.runner.invoke(ctl, ['flush', 'dummy', 'restart', '--force'])
             assert 'Failed: flush scheduled restart' in result.output
 
+    @patch('patroni.ctl.get_dcs')
+    @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
+    def test_flush_switchover(self, mock_get_dcs):
+        mock_get_dcs.return_value = self.e
+
+        mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
+        result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+        assert 'No pending scheduled switchover' in result.output
+
+        scheduled_at = datetime.now(tzutc) + timedelta(seconds=600)
+        mock_get_dcs.return_value.get_cluster = Mock(
+                return_value=get_cluster_initialized_with_leader(Failover(1, 'a', 'b', scheduled_at)))
+        result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+        assert result.output.startswith('Success: ')
+
+        mock_get_dcs.return_value.manual_failover = Mock()
+        with patch.object(PoolManager, 'request', side_effect=[MockResponse(409), Exception]):
+            result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+            assert 'Could not find any accessible member of cluster' in result.output
+
+    @patch.object(PoolManager, 'request')
     @patch('patroni.ctl.get_dcs')
     @patch('patroni.ctl.polling_loop', Mock(return_value=[1]))
-    def test_pause_cluster(self, mock_get_dcs):
+    def test_pause_cluster(self, mock_get_dcs, mock_post):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
 
-        with patch('requests.patch', Mock(return_value=MockResponse(500))):
+        mock_post.return_value.status = 500
         result = self.runner.invoke(ctl, ['pause', 'dummy'])
         assert 'Failed' in result.output
 
-        with patch('requests.patch', Mock(return_value=MockResponse(200))),\
+        mock_post.return_value.status = 200
-                patch('patroni.dcs.Cluster.is_paused', Mock(return_value=True)):
+        with patch('patroni.dcs.Cluster.is_paused', Mock(return_value=True)):
             result = self.runner.invoke(ctl, ['pause', 'dummy'])
             assert 'Cluster is already paused' in result.output
 
-        with patch('requests.patch', Mock(return_value=MockResponse(200))):
         result = self.runner.invoke(ctl, ['pause', 'dummy', '--wait'])
         assert "'pause' request sent" in result.output
         mock_get_dcs.return_value.get_cluster = Mock(side_effect=[get_cluster_initialized_with_leader(),
@@ -477,26 +508,26 @@ class TestCtl(unittest.TestCase):
                                                                   get_cluster(None, None, [member], None, None)])
         self.runner.invoke(ctl, ['pause', 'dummy', '--wait'])
 
+    @patch.object(PoolManager, 'request')
     @patch('patroni.ctl.get_dcs')
-    def test_resume_cluster(self, mock_get_dcs):
+    def test_resume_cluster(self, mock_get_dcs, mock_post):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
 
-        with patch('patroni.dcs.Cluster.is_paused', Mock(return_value=True)):
+        mock_post.return_value.status = 200
-            with patch('requests.patch', Mock(return_value=MockResponse(200))):
+        with patch('patroni.dcs.Cluster.is_paused', Mock(return_value=False)):
-                result = self.runner.invoke(ctl, ['resume', 'dummy'])
-                assert 'Success' in result.output
-
-            with patch('requests.patch', Mock(return_value=MockResponse(500))):
-                result = self.runner.invoke(ctl, ['resume', 'dummy'])
-                assert 'Failed' in result.output
-
-            with patch('requests.patch', Mock(return_value=MockResponse(200))),\
-                    patch('patroni.dcs.Cluster.is_paused', Mock(return_value=False)):
             result = self.runner.invoke(ctl, ['resume', 'dummy'])
             assert 'Cluster is not paused' in result.output
 
-            with patch('requests.patch', Mock(side_effect=Exception)):
+        with patch('patroni.dcs.Cluster.is_paused', Mock(return_value=True)):
+            result = self.runner.invoke(ctl, ['resume', 'dummy'])
+            assert 'Success' in result.output
+
+            mock_post.return_value.status = 500
+            result = self.runner.invoke(ctl, ['resume', 'dummy'])
+            assert 'Failed' in result.output
+
+            mock_post.side_effect = Exception
             result = self.runner.invoke(ctl, ['resume', 'dummy'])
             assert 'Can not find accessible cluster member' in result.output
 
@@ -574,16 +605,23 @@ class TestCtl(unittest.TestCase):
     def test_version(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
-        with patch('patroni.ctl.request_patroni') as mocked:
+        with patch.object(PoolManager, 'request') as mocked:
             result = self.runner.invoke(ctl, ['version'])
             assert 'patronictl version' in result.output
-            mocked.return_value.json = lambda: {'patroni': {'version': '1.2.3'}, 'server_version': 100001}
+            mocked.return_value.data = b'{"patroni":{"version":"1.2.3"},"server_version": 100001}'
             result = self.runner.invoke(ctl, ['version', 'dummy'])
             assert '1.2.3' in result.output
-        with patch('requests.get', Mock(side_effect=Exception)):
+        with patch.object(PoolManager, 'request', Mock(side_effect=Exception)):
             result = self.runner.invoke(ctl, ['version', 'dummy'])
             assert 'failed to get version' in result.output
 
+    @patch('patroni.ctl.get_dcs')
+    def test_history(self, mock_get_dcs):
+        mock_get_dcs.return_value.get_cluster = Mock()
+        mock_get_dcs.return_value.get_cluster.return_value.history.lines = [[1, 67176, 'no recovery target specified']]
+        result = self.runner.invoke(ctl, ['history'])
+        assert 'Reason' in result.output
+
     def test_format_pg_version(self):
         self.assertEqual(format_pg_version(100001), '10.1')
         self.assertEqual(format_pg_version(90605), '9.6.5')
@@ -596,3 +634,21 @@ class TestCtl(unittest.TestCase):
             self.assertIsNone(find_executable('vim'))
         with patch('os.path.isfile', Mock(side_effect=[False, True])):
             self.assertEqual(find_executable('vim', '/'), '/vim.exe')
+
+    @patch('patroni.ctl.get_dcs')
+    def test_get_members(self, mock_get_dcs):
+        mock_get_dcs.return_value = self.e
+        mock_get_dcs.return_value.get_cluster = get_cluster_not_initialized_without_leader
+        result = self.runner.invoke(ctl, ['reinit', 'dummy'])
+        assert "cluster doesn\'t have any members" in result.output
+
+    @patch('time.sleep', Mock())
+    @patch('patroni.ctl.get_dcs')
+    def test_reinit_wait(self, mock_get_dcs):
+        mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
+        with patch.object(PoolManager, 'request') as mocked:
+            mocked.side_effect = [Mock(data=s, status=200) for s in
+                                  [b"reinitialize", b'{"state":"creating replica"}', b'{"state":"running"}']]
+            result = self.runner.invoke(ctl, ['reinit', 'alpha', 'other', '--wait'], input='y\ny')
+        self.assertIn("Waiting for reinitialize to complete on: other", result.output)
+        self.assertIn("Reinitialize is completed on: other", result.output)

tests/test_etcd.py

@@ -5,8 +5,9 @@ import unittest
 
 from dns.exception import DNSException
 from mock import Mock, patch
-from patroni.dcs.etcd import AbstractDCS, Client, Cluster, Etcd, EtcdError, DnsCachingResolver
+from patroni.dcs.etcd import AbstractDCS, EtcdClient, Cluster, Etcd, EtcdError, DnsCachingResolver
 from patroni.exceptions import DCSError
+from patroni.utils import Retry
 from urllib3.exceptions import ReadTimeoutError
 
 from . import SleepException, MockResponse, requests_get
@@ -16,7 +17,7 @@ def etcd_watch(self, key, index=None, timeout=None, recursive=None):
     if timeout == 2.0:
         raise etcd.EtcdWatchTimedOut
     elif timeout == 5.0:
-        return etcd.EtcdResult('delete', {})
+        return etcd.EtcdResult('compareAndSwap', {})
     elif 5 < timeout <= 10.0:
         raise etcd.EtcdException
     elif timeout == 20.0:
@@ -115,26 +116,25 @@ class TestDnsCachingResolver(unittest.TestCase):
 
 @patch('dns.resolver.query', dns_query)
 @patch('socket.getaddrinfo', socket_getaddrinfo)
-@patch('requests.get', requests_get)
+@patch('patroni.dcs.etcd.requests_get', requests_get)
 class TestClient(unittest.TestCase):
 
     @patch('dns.resolver.query', dns_query)
     @patch('socket.getaddrinfo', socket_getaddrinfo)
-    @patch('requests.get', requests_get)
+    @patch('patroni.dcs.etcd.requests_get', requests_get)
     def setUp(self):
-        with patch.object(Client, 'machines') as mock_machines:
+        with patch.object(EtcdClient, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(return_value=['http://localhost:2379', 'http://localhost:4001'])
-            self.client = Client({'srv': 'test', 'retry_timeout': 3}, DnsCachingResolver())
+            self.client = EtcdClient({'srv': 'test', 'retry_timeout': 3}, DnsCachingResolver())
             self.client.http.request = http_request
             self.client.http.request_encode_body = http_request
 
     def test_machines(self):
-        self.client._base_uri = 'http://localhost:4001'
+        self.client._base_uri = 'http://localhost:4002'
-        self.client._machines_cache = ['http://localhost:2379']
+        self.client._machines_cache = ['http://localhost:4002', 'http://localhost:2379']
         self.assertIsNotNone(self.client.machines)
         self.client._base_uri = 'http://localhost:4001'
-        self.client._machines_cache = []
+        self.client._machines_cache = ['http://localhost:4001']
-        self.assertIsNotNone(self.client.machines)
         self.client._update_machines_cache = True
         machines = None
         try:
@@ -143,21 +143,31 @@ class TestClient(unittest.TestCase):
         except Exception:
             self.assertIsNone(machines)
 
-    @patch.object(Client, 'machines')
+    @patch.object(EtcdClient, 'machines')
     def test_api_execute(self, mock_machines):
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
+        mock_machines.__get__ = Mock(return_value=['http://localhost:4001', 'http://localhost:2379'])
-        self.assertRaises(ValueError, self.client.api_execute, '', '')
         self.client._base_uri = 'http://localhost:4001'
-        self.client._machines_cache = ['http://localhost:2379']
+        self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', 'POST', timeout=0)
-        self.client.api_execute('/', 'POST', timeout=0)
+        self.client._base_uri = 'http://localhost:4001'
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
+        rtry = Retry(deadline=10, max_delay=1, max_tries=-1, retry_exceptions=(etcd.EtcdLeaderElectionInProgress,))
+        rtry(self.client.api_execute, '/', 'POST', timeout=0, params={'retry': rtry})
         self.client._machines_cache_updated = 0
         self.client.api_execute('/', 'POST', timeout=0)
         self.client._machines_cache = [self.client._base_uri]
         self.assertRaises(etcd.EtcdWatchTimedOut, self.client.api_execute, '/timeout', 'POST', params={'wait': 'true'})
         self.assertRaises(etcd.EtcdWatchTimedOut, self.client.api_execute, '/timeout', 'POST', params={'wait': 'true'})
-        self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', '')
+
-        with patch.object(Client, '_load_machines_cache', Mock(side_effect=etcd.EtcdException)):
+        with patch.object(EtcdClient, '_calculate_timeouts', Mock(side_effect=[(1, 1, 0), (1, 1, 0), (0, 1, 0)])),\
+                patch.object(EtcdClient, '_load_machines_cache', Mock(side_effect=Exception)):
+            self.client.http.request = Mock(side_effect=socket.error)
+            self.assertRaises(etcd.EtcdException, rtry, self.client.api_execute, '/', 'GET', params={'retry': rtry})
+
+        with patch.object(EtcdClient, '_calculate_timeouts', Mock(side_effect=[(1, 1, 0), (1, 1, 0), (0, 1, 0)])),\
+                patch.object(EtcdClient, '_load_machines_cache', Mock(return_value=True)):
+            self.assertRaises(etcd.EtcdException, rtry, self.client.api_execute, '/', 'GET', params={'retry': rtry})
+
+        with patch.object(EtcdClient, '_do_http_request', Mock(side_effect=etcd.EtcdException)):
+            self.client._read_timeout = 0.01
             self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', 'GET')
 
     def test_get_srv_record(self):
@@ -172,9 +182,13 @@ class TestClient(unittest.TestCase):
     def test__get_machines_cache_from_dns(self):
         self.client._get_machines_cache_from_dns('error', 2379)
 
-    @patch.object(Client, 'machines')
+    @patch.object(EtcdClient, 'machines')
-    def test__load_machines_cache(self, mock_machines):
+    def test__refresh_machines_cache(self, mock_machines):
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
+        mock_machines.__get__ = Mock(side_effect=etcd.EtcdConnectionFailed)
+        self.assertIsNone(self.client._refresh_machines_cache())
+        self.assertRaises(etcd.EtcdException, self.client._refresh_machines_cache, True)
+
+    def test__load_machines_cache(self):
         self.client._config = {}
         self.assertRaises(Exception, self.client._load_machines_cache)
         self.client._config = {'srv': 'blabla'}
@@ -189,8 +203,12 @@ class TestClient(unittest.TestCase):
                           timeout=1, source_address=('localhost', 53333),
                           socket_options=[(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)])
 
+    def test___del__(self):
+        self.client.http.clear = Mock(side_effect=TypeError)
+        del self.client
 
-@patch('requests.get', requests_get)
+
+@patch('patroni.dcs.etcd.requests_get', requests_get)
 @patch('socket.getaddrinfo', socket_getaddrinfo)
 @patch.object(etcd.Client, 'write', etcd_write)
 @patch.object(etcd.Client, 'read', etcd_read)
@@ -199,7 +217,7 @@ class TestEtcd(unittest.TestCase):
 
     @patch('socket.getaddrinfo', socket_getaddrinfo)
     def setUp(self):
-        with patch.object(Client, 'machines') as mock_machines:
+        with patch.object(EtcdClient, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(return_value=['http://localhost:2379', 'http://localhost:4001'])
             self.etcd = Etcd({'namespace': '/patroni/', 'ttl': 30, 'retry_timeout': 10,
                               'host': 'localhost:2379', 'scope': 'test', 'name': 'foo'})
@@ -210,17 +228,18 @@ class TestEtcd(unittest.TestCase):
     @patch('dns.resolver.query', dns_query)
     def test_get_etcd_client(self):
         with patch('time.sleep', Mock(side_effect=SleepException)),\
-                patch.object(Client, 'machines') as mock_machines:
+                patch.object(EtcdClient, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(side_effect=etcd.EtcdException)
             self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                              {'discovery_srv': 'test', 'retry_timeout': 10, 'cacert': '1', 'key': '1', 'cert': 1})
+                              {'discovery_srv': 'test', 'retry_timeout': 10, 'cacert': '1', 'key': '1', 'cert': 1},
+                              EtcdClient)
             self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                              {'url': 'https://test:2379', 'retry_timeout': 10})
+                              {'url': 'https://test:2379', 'retry_timeout': 10}, EtcdClient)
             self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                              {'hosts': 'foo:4001,bar', 'retry_timeout': 10})
+                              {'hosts': 'foo:4001,bar', 'retry_timeout': 10}, EtcdClient)
             mock_machines.__get__ = Mock(return_value=[])
             self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                              {'proxy': 'https://user:password@test:2379', 'retry_timeout': 10})
+                              {'proxy': 'https://user:password@test:2379', 'retry_timeout': 10}, EtcdClient)
 
     def test_get_cluster(self):
         cluster = self.etcd.get_cluster()
@@ -269,6 +288,7 @@ class TestEtcd(unittest.TestCase):
         self.etcd.watch(None, 0)
         self.etcd.get_cluster()
         self.etcd.watch(20729, 1.5)
+        with patch('time.sleep', Mock()):
             self.etcd.watch(20729, 4.5)
         with patch.object(AbstractDCS, 'watch', Mock()):
             self.assertTrue(self.etcd.watch(20729, 19.5))

tests/test_etcd3.py

@@ -0,0 +1,246 @@
+import etcd
+import json
+import unittest
+import urllib3
+
+from mock import Mock, patch
+from patroni.dcs.etcd3 import PatroniEtcd3Client, Cluster, Etcd3, Etcd3Error, Etcd3ClientError, RetryFailedError,\
+        InvalidAuthToken, Unavailable, Unknown, UnsupportedEtcdVersion, UserEmpty, base64_encode
+from threading import Thread
+
+from . import SleepException, MockResponse
+
+
+def mock_urlopen(self, method, url, **kwargs):
+    ret = MockResponse()
+    if method == 'GET' and url.endswith('/version'):
+        ret.content = '{"etcdserver": "3.3.13", "etcdcluster": "3.3.0"}'
+    elif method != 'POST':
+        raise Exception('Unexpected request method: {0} {1} {2}'.format(method, url, kwargs))
+    elif url.endswith('/cluster/member/list'):
+        ret.content = '{"members":[{"clientURLs":["http://localhost:2379", "http://localhost:4001"]}]}'
+    elif url.endswith('/auth/authenticate'):
+        ret.content = '{"token":"authtoken"}'
+    elif url.endswith('/lease/grant'):
+        ret.content = '{"ID": "123"}'
+    elif url.endswith('/lease/keepalive'):
+        ret.content = '{"result":{"TTL":30}}'
+    elif url.endswith('/kv/range'):
+        ret.content = json.dumps({
+            "header": {"revision": "1"},
+            "kvs": [
+                {"key": base64_encode('/patroni/test/leader'),
+                 "value": base64_encode('foo'), "lease": "bla", "mod_revision": '1'},
+                {"key": base64_encode('/patroni/test/members/foo'),
+                 "value": base64_encode('{}'), "lease": "123", "mod_revision": '1'},
+                {"key": base64_encode('/patroni/test/failover'), "value": base64_encode('{}'), "mod_revision": '1'}
+            ]
+        })
+    elif url.endswith('/watch'):
+        key = base64_encode('/patroni/test/config')
+        ret.read_chunked = Mock(return_value=[json.dumps({
+            'result': {'events': [
+                {'kv': {'key': key, 'value': base64_encode('bar'), 'mod_revision': '2'}},
+                {'kv': {'key': key, 'value': base64_encode('buzz'), 'mod_revision': '3'}},
+                {'type': 'DELETE', 'kv': {'key': key, 'mod_revision': '4'}},
+                {'kv': {'key': base64_encode('/patroni/test/optime/leader'),
+                        'value': base64_encode('1234567'), 'mod_revision': '5'}},
+            ]}
+        })[:-1].encode('utf-8'), b'}{"error":{"grpc_code":14,"message":"","http_code":503}}'])
+    elif url.endswith('/kv/put') or url.endswith('/kv/txn'):
+        ret.status_code = 400
+        ret.content = '{"code":5,"error":"etcdserver: requested lease not found"}'
+    elif not url.endswith('/kv/deleterange'):
+        raise Exception('Unexpected url: {0} {1} {2}'.format(method, url, kwargs))
+    return ret
+
+
+class BaseTestEtcd3(unittest.TestCase):
+
+    @patch.object(Thread, 'start', Mock())
+    @patch.object(urllib3.PoolManager, 'urlopen', mock_urlopen)
+    def setUp(self):
+        self.etcd3 = Etcd3({'namespace': '/patroni/', 'ttl': 30, 'retry_timeout': 10,
+                            'host': 'localhost:2378', 'scope': 'test', 'name': 'foo',
+                            'username': 'etcduser', 'password': 'etcdpassword'})
+        self.client = self.etcd3._client
+        self.kv_cache = self.client._kv_cache
+
+
+class TestKVCache(BaseTestEtcd3):
+
+    def test__do_watch(self):
+        self.client.watchprefix = Mock(return_value=False)
+        self.assertRaises(AttributeError, self.kv_cache._do_watch, '1')
+
+    @patch('time.sleep', Mock(side_effect=SleepException))
+    @patch('patroni.dcs.etcd3.KVCache._build_cache', Mock(side_effect=Exception))
+    def test_run(self):
+        self.assertRaises(SleepException, self.kv_cache.run)
+
+    @patch.object(urllib3.PoolManager, 'urlopen', mock_urlopen)
+    def test_kill_stream(self):
+        self.assertRaises(Unavailable, self.kv_cache._do_watch, '1')
+        self.kv_cache.kill_stream()
+        with patch.object(MockResponse, 'connection', create=True) as mock_conn:
+            self.kv_cache.kill_stream()
+            mock_conn.sock.close.side_effect = Exception
+            self.kv_cache.kill_stream()
+
+
+class TestPatroniEtcd3Client(BaseTestEtcd3):
+
+    @patch('patroni.dcs.etcd3.Etcd3Client.authenticate', Mock(side_effect=Exception))
+    def test__init__(self):
+        self.assertRaises(SystemExit, self.setUp)
+
+    @patch.object(urllib3.PoolManager, 'urlopen')
+    def test_call_rpc(self, mock_urlopen):
+        request = {'key': base64_encode('/patroni/test/leader')}
+        mock_urlopen.return_value = MockResponse()
+        mock_urlopen.return_value.content = '{"succeeded":true,"header":{"revision":"1"}}'
+        self.client.call_rpc('/kv/txn', {'success': [{'request_delete_range': request}]})
+        self.client.call_rpc('/kv/put', request)
+        self.client.call_rpc('/kv/deleterange', request)
+
+    @patch('time.time', Mock(side_effect=[1, 10.9, 100]))
+    def test__wait_cache(self):
+        with self.kv_cache.condition:
+            self.assertRaises(RetryFailedError, self.client._wait_cache, 10)
+
+    @patch.object(urllib3.PoolManager, 'urlopen')
+    def test__restart_watcher(self, mock_urlopen):
+        mock_urlopen.return_value = MockResponse()
+        mock_urlopen.return_value.status_code = 400
+        mock_urlopen.return_value.content = '{"code":9,"error":"etcdserver: authentication is not enabled"}'
+        self.client.authenticate()
+
+    @patch.object(urllib3.PoolManager, 'urlopen')
+    def test__handle_auth_errors(self, mock_urlopen):
+        mock_urlopen.return_value = MockResponse()
+        mock_urlopen.return_value.content = '{"code":3,"error":"etcdserver: user name is empty"}'
+        mock_urlopen.return_value.status_code = 403
+        self.client._cluster_version = (3, 1, 5)
+        self.assertRaises(UnsupportedEtcdVersion, self.client.deleteprefix, 'foo')
+        self.client._cluster_version = (3, 3, 13)
+        self.assertRaises(UserEmpty, self.client.deleteprefix, 'foo')
+        mock_urlopen.return_value.content = '{"code":16,"error":"etcdserver: invalid auth token"}'
+        self.assertRaises(InvalidAuthToken, self.client.deleteprefix, 'foo')
+        with patch.object(PatroniEtcd3Client, 'authenticate', Mock(return_value=True)):
+            self.assertRaises(InvalidAuthToken, self.client.deleteprefix, 'foo')
+            self.client.username = None
+            self.assertRaises(InvalidAuthToken, self.client.deleteprefix, 'foo')
+
+    def test__handle_server_response(self):
+        response = MockResponse()
+        response.content = '{"code":0,"error":"'
+        self.assertRaises(etcd.EtcdException, self.client._handle_server_response, response)
+        response.status_code = 400
+        self.assertRaises(Unknown, self.client._handle_server_response, response)
+        response.content = '{"error":{"grpc_code":0,"message":"","http_code":400}}'
+        try:
+            self.client._handle_server_response(response)
+        except Unknown as e:
+            self.assertEqual(e.as_dict(), {'code': 2, 'codeText': 'OK', 'error': u'', 'status': 400})
+
+    @patch.object(urllib3.PoolManager, 'urlopen')
+    def test__ensure_version_prefix(self, mock_urlopen):
+        self.client.version_prefix = None
+        mock_urlopen.return_value = MockResponse()
+        mock_urlopen.return_value.content = '{"etcdserver": "3.0.3", "etcdcluster": "3.0.0"}'
+        self.assertRaises(UnsupportedEtcdVersion, self.client._ensure_version_prefix, '')
+        mock_urlopen.return_value.content = '{"etcdserver": "3.0.4", "etcdcluster": "3.0.0"}'
+        self.client._ensure_version_prefix('')
+        self.assertEqual(self.client.version_prefix, '/v3alpha')
+        mock_urlopen.return_value.content = '{"etcdserver": "3.4.4", "etcdcluster": "3.4.0"}'
+        self.client._ensure_version_prefix('')
+        self.assertEqual(self.client.version_prefix, '/v3')
+
+
+@patch.object(urllib3.PoolManager, 'urlopen', mock_urlopen)
+class TestEtcd3(BaseTestEtcd3):
+
+    @patch.object(Thread, 'start', Mock())
+    @patch.object(urllib3.PoolManager, 'urlopen', mock_urlopen)
+    def setUp(self):
+        super(TestEtcd3, self).setUp()
+        self.assertRaises(AttributeError, self.kv_cache._build_cache)
+        self.kv_cache._is_ready = True
+        self.etcd3.get_cluster()
+
+    def test_get_cluster(self):
+        self.assertIsInstance(self.etcd3.get_cluster(), Cluster)
+        self.client._kv_cache = None
+        with patch.object(urllib3.PoolManager, 'urlopen') as mock_urlopen:
+            mock_urlopen.side_effect = UnsupportedEtcdVersion('')
+            self.assertRaises(UnsupportedEtcdVersion, self.etcd3.get_cluster)
+            mock_urlopen.side_effect = SleepException()
+            self.assertRaises(Etcd3Error, self.etcd3.get_cluster)
+
+    def test_touch_member(self):
+        self.etcd3.touch_member({})
+        self.etcd3._lease = 'bla'
+        self.etcd3.touch_member({})
+        with patch.object(PatroniEtcd3Client, 'lease_grant', Mock(side_effect=Etcd3ClientError)):
+            self.etcd3.touch_member({})
+
+    def test__update_leader(self):
+        self.etcd3._lease = None
+        self.etcd3.update_leader('123')
+        self.etcd3.update_leader('124')
+
+    def test_attempt_to_acquire_leader(self):
+        self.etcd3._lease = None
+        self.assertFalse(self.etcd3.attempt_to_acquire_leader())
+
+    def test_set_ttl(self):
+        self.etcd3.set_ttl(20)
+
+    @patch.object(PatroniEtcd3Client, 'lease_keepalive', Mock(return_value=False))
+    def test_refresh_lease(self):
+        self.etcd3._last_lease_refresh = 0
+        self.etcd3.refresh_lease()
+
+    @patch('time.sleep', Mock(side_effect=SleepException))
+    @patch.object(PatroniEtcd3Client, 'lease_keepalive', Mock(return_value=False))
+    @patch.object(PatroniEtcd3Client, 'lease_grant', Mock(side_effect=Etcd3ClientError))
+    def test_create_lease(self):
+        self.etcd3._lease = None
+        self.etcd3._last_lease_refresh = 0
+        self.assertRaises(SleepException, self.etcd3.create_lease)
+
+    def test_set_failover_value(self):
+        self.etcd3.set_failover_value('', 1)
+
+    def test_set_config_value(self):
+        self.etcd3.set_config_value('')
+
+    def test_initialize(self):
+        self.etcd3.initialize()
+
+    def test_cancel_initialization(self):
+        self.etcd3.cancel_initialization()
+
+    def test_delete_leader(self):
+        self.etcd3.delete_leader()
+
+    def test_delete_cluster(self):
+        self.etcd3.delete_cluster()
+
+    def test_set_history_value(self):
+        self.etcd3.set_history_value('')
+
+    def test_set_sync_state_value(self):
+        self.etcd3.set_sync_state_value('')
+
+    def test_delete_sync_state(self):
+        self.etcd3.delete_sync_state()
+
+    def test_watch(self):
+        self.etcd3.set_ttl(10)
+        self.etcd3.watch(None, 0)
+        self.etcd3.watch(None, 0)
+
+    def test_set_socket_options(self):
+        with patch('socket.SIO_KEEPALIVE_VALS', 1, create=True):
+            self.etcd3.set_socket_options(Mock(), None)

tests/test_exhibitor.py

@@ -1,4 +1,5 @@
 import unittest
+import urllib3
 
 from mock import Mock, patch
 from patroni.dcs.exhibitor import ExhibitorEnsembleProvider, Exhibitor
@@ -8,7 +9,7 @@ from . import SleepException, requests_get
 from .test_zookeeper import MockKazooClient
 
 
-@patch('requests.get', requests_get)
+@patch('patroni.dcs.exhibitor.requests_get', requests_get)
 @patch('time.sleep', Mock(side_effect=SleepException))
 class TestExhibitorEnsembleProvider(unittest.TestCase):
 
@@ -21,7 +22,8 @@ class TestExhibitorEnsembleProvider(unittest.TestCase):
 
 class TestExhibitor(unittest.TestCase):
 
-    @patch('requests.get', requests_get)
+    @patch('urllib3.PoolManager.request', Mock(return_value=urllib3.HTTPResponse(
+        status=200, body=b'{"servers":["127.0.0.1","127.0.0.2","127.0.0.3"],"port":2181}')))
     @patch('patroni.dcs.zookeeper.KazooClient', MockKazooClient)
     def setUp(self):
         self.e = Exhibitor({'hosts': ['localhost', 'exhibitor'], 'port': 8181, 'scope': 'test',

tests/test_ha.py

@@ -3,11 +3,11 @@ import etcd
 import os
 import sys
 
-from mock import Mock, MagicMock, PropertyMock, patch
+from mock import call, Mock, MagicMock, PropertyMock, patch, mock_open
 from patroni.config import Config
 from patroni.dcs import Cluster, ClusterConfig, Failover, Leader, Member, get_dcs, SyncState, TimelineHistory
-from patroni.dcs.etcd import Client
+from patroni.dcs.etcd import AbstractEtcdClientWithFailover
-from patroni.exceptions import DCSError, PostgresConnectionException, PatroniException
+from patroni.exceptions import DCSError, PostgresConnectionException, PatroniFatalException
 from patroni.ha import Ha, _MemberStatus
 from patroni.postgresql import Postgresql
 from patroni.postgresql.bootstrap import Bootstrap
@@ -17,6 +17,7 @@ from patroni.postgresql.rewind import Rewind
 from patroni.postgresql.slots import SlotsHandler
 from patroni.utils import tzutc
 from patroni.watchdog import Watchdog
+from six.moves import builtins
 
 from . import PostgresInit, MockPostmaster, psycopg2_connect, requests_get
 from .test_etcd import socket_getaddrinfo, etcd_read, etcd_write
@@ -47,7 +48,7 @@ def get_cluster_not_initialized_without_leader(cluster_config=None):
 def get_cluster_initialized_without_leader(leader=False, failover=None, sync=None, cluster_config=None):
     m1 = Member(0, 'leader', 28, {'conn_url': 'postgres://replicator:[email protected]:5435/postgres',
                                   'api_url': 'http://127.0.0.1:8008/patroni', 'xlog_location': 4})
-    leader = Leader(0, 0, m1) if leader else None
+    leader = Leader(0, 0, m1 if leader else Member(0, '', 28, {}))
     m2 = Member(0, 'other', 28, {'conn_url': 'postgres://replicator:[email protected]:5436/postgres',
                                  'api_url': 'http://127.0.0.1:8011/patroni',
                                  'state': 'running',
@@ -122,7 +123,7 @@ zookeeper:
         # all the extra values that are coming from py.test
         sys.argv = sys.argv[:1]
 
-        self.config = Config()
+        self.config = Config(None)
         self.config.set_dynamic_configuration({'maximum_lag_on_failover': 5})
         self.version = '1.5.7'
         self.postgresql = p
@@ -137,27 +138,35 @@ zookeeper:
         self.scheduled_restart = {'schedule': future_restart_time,
                                   'postmaster_start_time': str(postmaster_start_time)}
         self.watchdog = Watchdog(self.config)
+        self.request = lambda member, **kwargs: requests_get(member.api_url, **kwargs)
 
 
 def run_async(self, func, args=()):
-    return func(*args) if args else func()
+    self.reset_scheduled_action()
+    if args:
+        func(*args)
+    else:
+        func()
 
 
 @patch.object(Postgresql, 'is_running', Mock(return_value=MockPostmaster()))
 @patch.object(Postgresql, 'is_leader', Mock(return_value=True))
-@patch.object(Postgresql, 'timeline_wal_position', Mock(return_value=(1, 10)))
+@patch.object(Postgresql, 'timeline_wal_position', Mock(return_value=(1, 10, 1)))
 @patch.object(Postgresql, '_cluster_info_state_get', Mock(return_value=3))
-@patch.object(Postgresql, 'call_nowait', Mock(return_value=True))
 @patch.object(Postgresql, 'data_directory_empty', Mock(return_value=False))
-@patch.object(Postgresql, 'controldata', Mock(return_value={'Database system identifier': SYSID}))
+@patch.object(Postgresql, 'controldata', Mock(return_value={
+    'Database system identifier': SYSID,
+    'Database cluster state': 'shut down',
+    'Latest checkpoint location': '0/12345678'}))
 @patch.object(SlotsHandler, 'sync_replication_slots', Mock())
 @patch.object(ConfigHandler, 'append_pg_hba', Mock())
-@patch.object(Postgresql, 'write_pgpass', Mock(return_value={}))
+@patch.object(ConfigHandler, 'write_pgpass', Mock(return_value={}))
 @patch.object(ConfigHandler, 'write_recovery_conf', Mock())
+@patch.object(ConfigHandler, 'write_postgresql_conf', Mock())
 @patch.object(Postgresql, 'query', Mock())
 @patch.object(Postgresql, 'checkpoint', Mock())
 @patch.object(CancellableSubprocess, 'call', Mock(return_value=0))
-@patch.object(Postgresql, 'get_local_timeline_lsn_from_replication_connection', Mock(return_value=[2, 10]))
+@patch.object(Postgresql, 'get_replica_timeline', Mock(return_value=2))
 @patch.object(Postgresql, 'get_master_timeline', Mock(return_value=2))
 @patch.object(ConfigHandler, 'restore_configuration_files', Mock())
 @patch.object(etcd.Client, 'write', etcd_write)
@@ -166,16 +175,17 @@ def run_async(self, func, args=()):
 @patch('patroni.postgresql.polling_loop', Mock(return_value=range(1)))
 @patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=False))
 @patch('patroni.async_executor.AsyncExecutor.run_async', run_async)
+@patch('patroni.postgresql.rewind.Thread', Mock())
 @patch('subprocess.call', Mock(return_value=0))
 @patch('time.sleep', Mock())
 class TestHa(PostgresInit):
 
     @patch('socket.getaddrinfo', socket_getaddrinfo)
-    @patch('patroni.dcs.dcs_modules', Mock(return_value=['patroni.dcs.foo', 'patroni.dcs.etcd']))
+    @patch('patroni.dcs.dcs_modules', Mock(return_value=['patroni.dcs.etcd']))
     @patch.object(etcd.Client, 'read', etcd_read)
     def setUp(self):
         super(TestHa, self).setUp()
-        with patch.object(Client, 'machines') as mock_machines:
+        with patch.object(AbstractEtcdClientWithFailover, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
             self.p.set_state('running')
             self.p.set_role('replica')
@@ -192,10 +202,14 @@ class TestHa(PostgresInit):
         self.p.last_operation = Mock(side_effect=PostgresConnectionException(''))
         self.assertTrue(self.ha.update_lock(True))
 
+    @patch.object(Postgresql, 'received_timeline', Mock(return_value=None))
     def test_touch_member(self):
-        self.p.timeline_wal_position = Mock(return_value=(0, 1))
+        self.p.timeline_wal_position = Mock(return_value=(0, 1, 0))
         self.p.replica_cached_timeline = Mock(side_effect=Exception)
         self.ha.touch_member()
+        self.p.timeline_wal_position = Mock(return_value=(0, 1, 1))
+        self.p.set_role('standby_leader')
+        self.ha.touch_member()
 
     def test_is_leader(self):
         self.assertFalse(self.ha.is_leader())
@@ -244,7 +258,7 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.assertEqual(self.ha.run_cycle(), 'starting as readonly because i had the session lock')
 
-    @patch.object(Postgresql, 'fix_cluster_state', Mock())
+    @patch.object(Rewind, 'ensure_clean_shutdown', Mock())
     def test_crash_recovery(self):
         self.p.is_running = false
         self.p.controldata = lambda: {'Database cluster state': 'in production', 'Database system identifier': SYSID}
@@ -288,6 +302,19 @@ class TestHa(PostgresInit):
         self.p.is_leader = false
         self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
 
+    def test_promotion_cancelled_after_pre_promote_failed(self):
+        self.p.is_leader = false
+        self.p._pre_promote = false
+        self.ha._is_healthiest_node = true
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'Promotion cancelled because the pre-promote script failed')
+        self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
+
+    def test_lost_leader_lock_during_promote(self):
+        with patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=True)):
+            self.ha._async_executor.schedule('promote')
+            self.assertEqual(self.ha.run_cycle(), 'lost leader before promote')
+
     def test_long_promote(self):
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
@@ -353,6 +380,7 @@ class TestHa(PostgresInit):
         self.p.is_leader = false
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
         self.ha.patroni.replicatefrom = "foo"
+        self.p.config.check_recovery_conf = Mock(return_value=(True, False))
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
 
     def test_follow_in_pause(self):
@@ -407,7 +435,7 @@ class TestHa(PostgresInit):
         self.e.initialize = true
         self.ha.bootstrap()
         self.p.is_running = false
-        self.assertRaises(PatroniException, self.ha.post_bootstrap)
+        self.assertRaises(PatroniFatalException, self.ha.post_bootstrap)
 
     def test_bootstrap_release_initialize_key_on_watchdog_failure(self):
         self.ha.cluster = get_cluster_not_initialized_without_leader()
@@ -417,7 +445,7 @@ class TestHa(PostgresInit):
         self.p.is_leader = true
         with patch.object(Watchdog, 'activate', Mock(return_value=False)):
             self.assertEqual(self.ha.post_bootstrap(), 'running post_bootstrap')
-            self.assertRaises(PatroniException, self.ha.post_bootstrap)
+            self.assertRaises(PatroniFatalException, self.ha.post_bootstrap)
 
     @patch('psycopg2.connect', psycopg2_connect)
     def test_reinitialize(self):
@@ -425,7 +453,7 @@ class TestHa(PostgresInit):
 
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.assertIsNone(self.ha.reinitialize(True))
-
+        self.ha._async_executor.schedule('reinitialize')
         self.assertIsNotNone(self.ha.reinitialize())
 
         self.ha.state_handler.name = self.ha.cluster.leader.name
@@ -439,7 +467,7 @@ class TestHa(PostgresInit):
         self.p.restart = false
         self.assertEqual(self.ha.restart({}), (False, 'restart failed'))
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.ha.reinitialize()
+        self.ha._async_executor.schedule('reinitialize')
         self.assertEqual(self.ha.restart({}), (False, 'reinitialize already in progress'))
         with patch.object(self.ha, "restart_matches", return_value=False):
             self.assertEqual(self.ha.restart({'foo': 'bar'}), (False, "restart conditions are not satisfied"))
@@ -447,7 +475,7 @@ class TestHa(PostgresInit):
     @patch('os.kill', Mock())
     def test_restart_in_progress(self):
         with patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=True)):
-            self.ha.restart({}, run_async=True)
+            self.ha._async_executor.schedule('restart')
             self.assertTrue(self.ha.restart_scheduled())
             self.assertEqual(self.ha.run_cycle(), 'restart in progress')
 
@@ -464,7 +492,6 @@ class TestHa(PostgresInit):
                     self.assertEqual(self.ha.run_cycle(), 'lost leader lock during restart')
                     mock_terminate.assert_called()
 
-    @patch('requests.get', requests_get)
     def test_manual_failover_from_leader(self):
         self.ha.fetch_node_status = get_node_status()
         self.ha.has_lock = true
@@ -512,7 +539,6 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
         self.assertEqual('no action.  i am the leader with the lock', self.ha.run_cycle())
 
-    @patch('requests.get', requests_get)
     def test_manual_failover_from_leader_in_pause(self):
         self.ha.has_lock = true
         self.ha.is_paused = true
@@ -522,7 +548,6 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
         self.assertEqual('PAUSE: no action.  i am the leader with the lock', self.ha.run_cycle())
 
-    @patch('requests.get', requests_get)
     def test_manual_failover_from_leader_in_synchronous_mode(self):
         self.p.is_leader = true
         self.ha.has_lock = true
@@ -535,7 +560,6 @@ class TestHa(PostgresInit):
         self.ha.is_failover_possible = true
         self.assertEqual('manual failover: demoting myself', self.ha.run_cycle())
 
-    @patch('requests.get', requests_get)
     def test_manual_failover_process_no_leader(self):
         self.p.is_leader = false
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', self.p.name, None))
@@ -585,7 +609,6 @@ class TestHa(PostgresInit):
         self.ha.is_paused = true
         self.assertFalse(self.ha.is_healthiest_node())
 
-    @patch('requests.get', requests_get)
     def test__is_healthiest_node(self):
         self.ha.cluster = get_cluster_initialized_without_leader(sync=('postgresql1', self.p.name))
         self.assertTrue(self.ha._is_healthiest_node(self.ha.old_cluster.members))
@@ -599,7 +622,7 @@ class TestHa(PostgresInit):
         # in synchronous_mode consider itself healthy if the former leader is accessible in read-only and ahead of us
         with patch.object(Ha, 'is_synchronous_mode', Mock(return_value=True)):
             self.assertTrue(self.ha._is_healthiest_node(self.ha.old_cluster.members))
-        with patch('patroni.postgresql.Postgresql.timeline_wal_position', return_value=(1, 1)):
+        with patch('patroni.postgresql.Postgresql.timeline_wal_position', return_value=(1, 1, 1)):
             self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
         with patch('patroni.postgresql.Postgresql.replica_cached_timeline', return_value=1):
             self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
@@ -607,19 +630,23 @@ class TestHa(PostgresInit):
         self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
         self.ha.patroni.nofailover = False
 
-    @patch('requests.get', requests_get)
     def test_fetch_node_status(self):
         member = Member(0, 'test', 1, {'api_url': 'http://127.0.0.1:8011/patroni'})
         self.ha.fetch_node_status(member)
         member = Member(0, 'test', 1, {'api_url': 'http://localhost:8011/patroni'})
         self.ha.fetch_node_status(member)
 
+    @patch.object(Rewind, 'pg_rewind', true)
+    @patch.object(Rewind, 'check_leader_is_not_in_recovery', true)
     def test_post_recover(self):
         self.p.is_running = false
         self.ha.has_lock = true
+        self.p.set_role('master')
         self.assertEqual(self.ha.post_recover(), 'removed leader key after trying and failing to start postgres')
         self.ha.has_lock = false
         self.assertEqual(self.ha.post_recover(), 'failed to start postgres')
+        leader = Leader(0, 0, Member(0, 'l', 2, {"version": "1.6", "conn_url": "postgres://a", "role": "master"}))
+        self.ha._rewind.execute(leader)
         self.p.is_running = true
         self.assertIsNone(self.ha.post_recover())
 
@@ -680,13 +707,19 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
         self.assertEqual(self.ha.run_cycle(), 'PAUSE: waiting to become master after promote...')
 
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', mock_open(read_data='1\t0/40159C0\tno recovery target specified\n'))
     def test_process_healthy_standby_cluster_as_standby_leader(self):
         self.p.is_leader = false
         self.p.name = 'leader'
         self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
-        self.p.config.check_recovery_conf = true
+        self.p.config.check_recovery_conf = Mock(return_value=(False, False))
+        self.ha._leader_timeline = 1
         self.assertEqual(self.ha.run_cycle(), 'promoted self to a standby leader because i had the session lock')
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am the standby leader with the lock')
+        self.p.set_role('replica')
+        self.p.config.check_recovery_conf = Mock(return_value=(True, False))
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to a standby leader because i had the session lock')
 
     def test_process_healthy_standby_cluster_as_cascade_replica(self):
         self.p.is_leader = false
@@ -696,7 +729,6 @@ class TestHa(PostgresInit):
         with patch.object(Leader, 'conn_url', PropertyMock(return_value='')):
             self.assertEqual(self.ha.run_cycle(), 'continue following the old known standby leader')
 
-    @patch('requests.get', requests_get)
     def test_process_unhealthy_standby_cluster_as_standby_leader(self):
         self.p.is_leader = false
         self.p.name = 'leader'
@@ -809,6 +841,17 @@ class TestHa(PostgresInit):
         self.assertEqual(self.ha.run_cycle(), 'stopped PostgreSQL to fail over after a crash')
         demote.assert_called_once()
 
+    def test_master_stop_timeout(self):
+        self.assertEqual(self.ha.master_stop_timeout(), None)
+        self.ha.patroni.config.set_dynamic_configuration({'master_stop_timeout': 30})
+        with patch.object(Ha, 'is_synchronous_mode', Mock(return_value=True)):
+            self.assertEqual(self.ha.master_stop_timeout(), 30)
+        self.ha.patroni.config.set_dynamic_configuration({'master_stop_timeout': 30})
+        with patch.object(Ha, 'is_synchronous_mode', Mock(return_value=False)):
+            self.assertEqual(self.ha.master_stop_timeout(), None)
+            self.ha.patroni.config.set_dynamic_configuration({'master_stop_timeout': None})
+            self.assertEqual(self.ha.master_stop_timeout(), None)
+
     @patch('patroni.postgresql.Postgresql.follow')
     def test_demote_immediate(self, follow):
         self.ha.has_lock = true
@@ -826,7 +869,7 @@ class TestHa(PostgresInit):
         with patch.object(self.ha.dcs, 'delete_sync_state') as mock_delete_sync:
             self.ha.run_cycle()
             mock_delete_sync.assert_called_once()
-            mock_set_sync.assert_called_once_with(None)
+            mock_set_sync.assert_called_once_with([])
 
         mock_set_sync.reset_mock()
         # Test sync key not touched when not there
@@ -834,14 +877,14 @@ class TestHa(PostgresInit):
         with patch.object(self.ha.dcs, 'delete_sync_state') as mock_delete_sync:
             self.ha.run_cycle()
             mock_delete_sync.assert_not_called()
-            mock_set_sync.assert_called_once_with(None)
+            mock_set_sync.assert_called_once_with([])
 
         mock_set_sync.reset_mock()
 
         self.ha.is_synchronous_mode = true
 
         # Test sync standby not touched when picking the same node
-        self.p.pick_synchronous_standby = Mock(return_value=('other', True))
+        self.p.pick_synchronous_standby = Mock(return_value=(['other'], ['other']))
         self.ha.cluster = get_cluster_initialized_with_leader(sync=('leader', 'other'))
         self.ha.run_cycle()
         mock_set_sync.assert_not_called()
@@ -849,10 +892,18 @@ class TestHa(PostgresInit):
         mock_set_sync.reset_mock()
 
         # Test sync standby is replaced when switching standbys
-        self.p.pick_synchronous_standby = Mock(return_value=('other2', False))
+        self.p.pick_synchronous_standby = Mock(return_value=(['other2'], []))
         self.ha.dcs.write_sync_state = Mock(return_value=True)
         self.ha.run_cycle()
-        mock_set_sync.assert_called_once_with('other2')
+        mock_set_sync.assert_called_once_with(['other2'])
+
+        # Test sync standby is replaced when new standby is joined
+        self.p.pick_synchronous_standby = Mock(return_value=(['other2', 'other3'], ['other2']))
+        self.ha.dcs.write_sync_state = Mock(return_value=True)
+        self.ha.run_cycle()
+        # mock_set_sync.assert_called_once_with(['other2'])
+        calls = [call(['other2']), call(['other2', 'other3'])]
+        mock_set_sync.assert_has_calls(calls)
 
         mock_set_sync.reset_mock()
         # Test sync standby is not disabled when updating dcs fails
@@ -865,7 +916,7 @@ class TestHa(PostgresInit):
         self.ha.dcs.write_sync_state = Mock(return_value=True)
         self.ha.dcs.get_cluster = Mock(return_value=get_cluster_initialized_with_leader(sync=('leader', 'other')))
         # self.ha.cluster = get_cluster_initialized_with_leader(sync=('leader', 'other'))
-        self.p.pick_synchronous_standby = Mock(return_value=('other2', True))
+        self.p.pick_synchronous_standby = Mock(return_value=(['other2'], ['other2']))
         self.ha.run_cycle()
         self.ha.dcs.get_cluster.assert_called_once()
         self.assertEqual(self.ha.dcs.write_sync_state.call_count, 2)
@@ -888,9 +939,9 @@ class TestHa(PostgresInit):
         # Test sync set to '*' when synchronous_mode_strict is enabled
         mock_set_sync.reset_mock()
         self.ha.is_synchronous_mode_strict = true
-        self.p.pick_synchronous_standby = Mock(return_value=(None, False))
+        self.p.pick_synchronous_standby = Mock(return_value=([], []))
         self.ha.run_cycle()
-        mock_set_sync.assert_called_once_with('*')
+        mock_set_sync.assert_called_once_with(['*'])
 
     def test_sync_replication_become_master(self):
         self.ha.is_synchronous_mode = true
@@ -905,7 +956,7 @@ class TestHa(PostgresInit):
 
         # When we just became master nobody is sync
         self.assertEqual(self.ha.enforce_master_role('msg', 'promote msg'), 'promote msg')
-        mock_set_sync.assert_called_once_with(None)
+        mock_set_sync.assert_called_once_with([])
         mock_write_sync.assert_called_once_with('leader', None, index=0)
 
         mock_set_sync.reset_mock()
@@ -987,6 +1038,8 @@ class TestHa(PostgresInit):
         self.ha._disable_sync = False
         self.assertEqual(self.ha.get_effective_tags(), {'foo': 'bar'})
 
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', Mock(side_effect=Exception))
     def test_restore_cluster_config(self):
         self.ha.cluster.config.data.clear()
         self.ha.has_lock = true
@@ -1002,7 +1055,7 @@ class TestHa(PostgresInit):
 
     def test_shutdown(self):
         self.p.is_running = false
-        self.ha.has_lock = true
+        self.ha.is_leader = true
         self.ha.shutdown()
 
     @patch('time.sleep', Mock())
@@ -1018,7 +1071,9 @@ class TestHa(PostgresInit):
         # will not say bootstrap from leader as replica can't self elect
         self.assertEqual(self.ha.run_cycle(), "trying to bootstrap from replica 'other'")
 
-    @patch('psycopg2.connect', psycopg2_connect)
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', mock_open(read_data=('1\t0/40159C0\tno recovery target specified\n\n'
+                                                         '2\t1/40159C0\tno recovery target specified\n')))
     def test_update_cluster_history(self):
         self.ha.has_lock = true
         self.ha.cluster.is_unlocked = false
@@ -1027,7 +1082,6 @@ class TestHa(PostgresInit):
             self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
 
     @patch('sys.exit', return_value=1)
-    @patch('requests.get', requests_get)
     def test_abort_join(self, exit_mock):
         self.ha.cluster = get_cluster_not_initialized_without_leader()
         self.p.is_leader = false
@@ -1050,3 +1104,10 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_without_leader(leader=True, cluster_config=config)
         self.ha.has_lock = true
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+
+    @patch.object(Cluster, 'has_member', true)
+    def test_run_cycle(self):
+        self.ha.dcs.touch_member = Mock(side_effect=DCSError('foo'))
+        self.assertEqual(self.ha.run_cycle(), 'Unexpected exception raised, please report it as a BUG')
+        self.ha.dcs.touch_member = Mock(side_effect=PatroniFatalException('foo'))
+        self.assertRaises(PatroniFatalException, self.ha.run_cycle)

tests/test_kubernetes.py

@@ -1,11 +1,18 @@
+import json
+import socket
 import time
 import unittest
 
-from mock import Mock, patch
+from mock import Mock, mock_open, patch
-from patroni.dcs.kubernetes import Kubernetes, KubernetesError, k8s_client, k8s_watch, RetryFailedError
+from patroni.dcs.kubernetes import k8s_client, k8s_config, K8sConfig, K8sConnectionFailed,\
+        K8sException, K8sObject, Kubernetes, KubernetesError, KubernetesRetriableException,\
+        Retry, RetryFailedError, SERVICE_HOST_ENV_NAME, SERVICE_PORT_ENV_NAME
+from six.moves import builtins
+from threading import Thread
+from . import MockResponse, SleepException
 
 
-def mock_list_namespaced_config_map(self, *args, **kwargs):
+def mock_list_namespaced_config_map(*args, **kwargs):
     metadata = {'resource_version': '1', 'labels': {'f': 'b'}, 'name': 'test-config',
                 'annotations': {'initialize': '123', 'config': '{}'}}
     items = [k8s_client.V1ConfigMap(metadata=k8s_client.V1ObjectMeta(**metadata))]
@@ -16,49 +23,179 @@ def mock_list_namespaced_config_map(self, *args, **kwargs):
     metadata.update({'name': 'test-sync', 'annotations': {'leader': 'p-0'}})
     items.append(k8s_client.V1ConfigMap(metadata=k8s_client.V1ObjectMeta(**metadata)))
     metadata = k8s_client.V1ObjectMeta(resource_version='1')
-    return k8s_client.V1ConfigMapList(metadata=metadata, items=items)
+    return k8s_client.V1ConfigMapList(metadata=metadata, items=items, kind='ConfigMapList')
 
 
-def mock_list_namespaced_pod(self, *args, **kwargs):
+def mock_list_namespaced_endpoints(*args, **kwargs):
-    metadata = k8s_client.V1ObjectMeta(resource_version='1', name='p-0', annotations={'status': '{}'})
+    target_ref = k8s_client.V1ObjectReference(kind='Pod', resource_version='10', name='p-0',
-    items = [k8s_client.V1Pod(metadata=metadata)]
+                                              namespace='default', uid='964dfeae-e79b-4476-8a5a-1920b5c2a69d')
-    return k8s_client.V1PodList(items=items)
+    address0 = k8s_client.V1EndpointAddress(ip='10.0.0.0', target_ref=target_ref)
+    address1 = k8s_client.V1EndpointAddress(ip='10.0.0.1')
+    port = k8s_client.V1EndpointPort(port=5432, name='postgresql', protocol='TCP')
+    subset = k8s_client.V1EndpointSubset(addresses=[address1, address0], ports=[port])
+    metadata = k8s_client.V1ObjectMeta(resource_version='1', labels={'f': 'b'}, name='test',
+                                       annotations={'optime': '1234', 'leader': 'p-0', 'ttl': '30s'})
+    endpoint = k8s_client.V1Endpoints(subsets=[subset], metadata=metadata)
+    metadata = k8s_client.V1ObjectMeta(resource_version='1')
+    return k8s_client.V1EndpointsList(metadata=metadata, items=[endpoint], kind='V1EndpointsList')
 
 
-@patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map', Mock())
+def mock_list_namespaced_pod(*args, **kwargs):
-@patch.object(k8s_client.CoreV1Api, 'create_namespaced_config_map', Mock())
+    metadata = k8s_client.V1ObjectMeta(resource_version='1', name='p-0', annotations={'status': '{}'},
-class TestKubernetes(unittest.TestCase):
+                                       uid='964dfeae-e79b-4476-8a5a-1920b5c2a69d')
+    status = k8s_client.V1PodStatus(pod_ip='10.0.0.0')
+    spec = k8s_client.V1PodSpec(hostname='p-0', node_name='kind-control-plane', containers=[])
+    items = [k8s_client.V1Pod(metadata=metadata, status=status, spec=spec)]
+    return k8s_client.V1PodList(items=items, kind='PodList')
 
-    @patch('kubernetes.config.load_kube_config', Mock())
+
-    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map)
+def mock_namespaced_kind(*args, **kwargs):
-    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod)
+    mock = Mock()
+    mock.metadata.resource_version = '2'
+    return mock
+
+
+def mock_load_k8s_config(self, *args, **kwargs):
+    self._server = ''
+
+
+class TestK8sConfig(unittest.TestCase):
+
+    def test_load_incluster_config(self):
+        for env in ({}, {SERVICE_HOST_ENV_NAME: '', SERVICE_PORT_ENV_NAME: ''}):
+            with patch('os.environ', env):
+                self.assertRaises(k8s_config.ConfigException, k8s_config.load_incluster_config)
+
+        with patch('os.environ', {SERVICE_HOST_ENV_NAME: 'a', SERVICE_PORT_ENV_NAME: '1'}),\
+                patch('os.path.isfile', Mock(side_effect=[False, True, True, False, True, True, True, True])),\
+                patch.object(builtins, 'open', Mock(side_effect=[
+                    mock_open()(), mock_open(read_data='a')(), mock_open(read_data='a')(),
+                    mock_open()(), mock_open(read_data='a')(), mock_open(read_data='a')()])):
+            for _ in range(0, 4):
+                self.assertRaises(k8s_config.ConfigException, k8s_config.load_incluster_config)
+            k8s_config.load_incluster_config()
+            self.assertEqual(k8s_config.server, 'https://a:1')
+
+    def test_load_kube_config(self):
+        config = {
+            "current-context": "local",
+            "contexts": [{"name": "local", "context": {"user": "local", "cluster": "local"}}],
+            "clusters": [{"name": "local", "cluster": {"server": "https://a:1/", "certificate-authority": "a"}}],
+            "users": [{"name": "local", "user": {"username": "a", "password": "b", "client-certificate": "c"}}]
+        }
+        with patch.object(builtins, 'open', mock_open(read_data=json.dumps(config))):
+            k8s_config.load_kube_config()
+            self.assertEqual(k8s_config.server, 'https://a:1')
+            self.assertEqual(k8s_config.pool_config, {'ca_certs': 'a', 'cert_file': 'c', 'cert_reqs': 'CERT_REQUIRED',
+                                                      'maxsize': 10, 'num_pools': 10})
+
+        config["users"][0]["user"]["token"] = "token"
+        with patch.object(builtins, 'open', mock_open(read_data=json.dumps(config))):
+            k8s_config.load_kube_config()
+            self.assertEqual(k8s_config.headers.get('authorization'), 'Bearer token')
+
+
+@patch('urllib3.PoolManager.request')
+class TestApiClient(unittest.TestCase):
+
+    @patch.object(K8sConfig, '_server', '', create=True)
+    @patch('urllib3.PoolManager.request', Mock())
     def setUp(self):
-        self.k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10, 'labels': {'f': 'b'}})
+        self.a = k8s_client.ApiClient(True)
+        self.mock_get_ep = MockResponse()
+        self.mock_get_ep.content = '{"subsets":[{"ports":[{"name":"https","protocol":"TCP","port":443}],' +\
+                                   '"addresses":[{"ip":"127.0.0.1"},{"ip":"127.0.0.2"}]}]}'
+
+    def test__do_http_request(self, mock_request):
+        mock_request.side_effect = [self.mock_get_ep] + [socket.timeout]
+        self.assertRaises(K8sException, self.a.call_api, 'GET', 'f')
+
+    @patch('time.sleep', Mock())
+    def test_request(self, mock_request):
+        retry = Retry(deadline=10, max_delay=1, max_tries=1, retry_exceptions=KubernetesRetriableException)
+        mock_request.side_effect = [self.mock_get_ep] + 3 * [socket.timeout] + [k8s_client.rest.ApiException(500, '')]
+        self.assertRaises(k8s_client.rest.ApiException, retry, self.a.call_api, 'GET', 'f', _retry=retry)
+        mock_request.side_effect = [self.mock_get_ep, socket.timeout, Mock(), self.mock_get_ep]
+        self.assertRaises(k8s_client.rest.ApiException, retry, self.a.call_api, 'GET', 'f', _retry=retry)
+        retry.deadline = 0.0001
+        mock_request.side_effect = [socket.timeout, socket.timeout, self.mock_get_ep]
+        self.assertRaises(K8sConnectionFailed, retry, self.a.call_api, 'GET', 'f', _retry=retry)
+
+    def test__refresh_api_servers_cache(self, mock_request):
+        mock_request.side_effect = k8s_client.rest.ApiException(403, '')
+        self.a.refresh_api_servers_cache()
+
+
+class TestCoreV1Api(unittest.TestCase):
+
+    @patch('urllib3.PoolManager.request', Mock())
+    @patch.object(K8sConfig, '_server', '', create=True)
+    def setUp(self):
+        self.a = k8s_client.CoreV1Api()
+        self.a._api_client.pool_manager.request = Mock(return_value=MockResponse())
+
+    def test_create_namespaced_service(self):
+        self.assertEqual(str(self.a.create_namespaced_service('default', {}, _request_timeout=2)), '{}')
+
+    def test_list_namespaced_endpoints(self):
+        self.a._api_client.pool_manager.request.return_value.content = '{"items": [1,2,3]}'
+        self.assertIsInstance(self.a.list_namespaced_endpoints('default'), K8sObject)
+
+    def test_patch_namespaced_config_map(self):
+        self.assertEqual(str(self.a.patch_namespaced_config_map('foo', 'default', {}, _request_timeout=(1, 2))), '{}')
+
+    def test_list_namespaced_pod(self):
+        self.a._api_client.pool_manager.request.return_value.status_code = 409
+        self.a._api_client.pool_manager.request.return_value.content = 'foo'
+        try:
+            self.a.list_namespaced_pod('default', label_selector='foo=bar')
+            self.assertFail()
+        except k8s_client.rest.ApiException as e:
+            self.assertTrue('Reason: ' in str(e))
+
+    def test_delete_namespaced_pod(self):
+        self.assertEqual(str(self.a.delete_namespaced_pod('foo', 'default', _request_timeout=(1, 2), body={})), '{}')
+
+
+class BaseTestKubernetes(unittest.TestCase):
+
+    @patch('urllib3.PoolManager.request', Mock())
+    @patch('socket.TCP_KEEPIDLE', 4, create=True)
+    @patch('socket.TCP_KEEPINTVL', 5, create=True)
+    @patch('socket.TCP_KEEPCNT', 6, create=True)
+    @patch.object(Thread, 'start', Mock())
+    @patch.object(K8sConfig, 'load_kube_config', mock_load_k8s_config)
+    @patch.object(K8sConfig, 'load_incluster_config', Mock(side_effect=k8s_config.ConfigException))
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod, create=True)
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map, create=True)
+    def setUp(self, config=None):
+        config = config or {}
+        config.update(ttl=30, scope='test', name='p-0', loop_wait=10,
+                      retry_timeout=10, labels={'f': 'b'}, bypass_api_service=True)
+        self.k = Kubernetes(config)
+        self.assertRaises(AttributeError, self.k._pods._build_cache)
+        self.k._pods._is_ready = True
+        self.assertRaises(TypeError, self.k._kinds._build_cache)
+        self.k._kinds._is_ready = True
         self.k.get_cluster()
 
+
+@patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map', mock_namespaced_kind, create=True)
+class TestKubernetesConfigMaps(BaseTestKubernetes):
+
+    @patch('time.time', Mock(side_effect=[1, 10.9, 100]))
+    def test__wait_caches(self):
+        self.k._pods._is_ready = False
+        with self.k._condition:
+            self.assertRaises(RetryFailedError, self.k._wait_caches, time.time() + 10)
+
+    @patch('time.time', Mock(return_value=time.time() + 100))
     def test_get_cluster(self):
-        with patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map), \
-                patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod), \
-                patch('time.time', Mock(return_value=time.time() + 31)):
         self.k.get_cluster()
 
-        with patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', Mock(side_effect=Exception)):
+        with patch.object(Kubernetes, '_wait_caches', Mock(side_effect=Exception)):
             self.assertRaises(KubernetesError, self.k.get_cluster)
 
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
-    def test_update_leader(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10,
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
-        self.assertIsNotNone(k.update_leader('123'))
-
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
-    def test_update_leader_with_restricted_access(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10,
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
-        self.assertIsNotNone(k.update_leader('123', True))
-
     def test_take_leader(self):
         self.k.take_leader()
         self.k._leader_observed_record['leader'] = 'test'
@@ -66,14 +203,16 @@ class TestKubernetes(unittest.TestCase):
         self.k.take_leader()
 
     def test_manual_failover(self):
-        with patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map', Mock(side_effect=RetryFailedError(''))):
+        with patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map',
+                          Mock(side_effect=RetryFailedError('')), create=True):
             self.k.manual_failover('foo', 'bar')
 
     def test_set_config_value(self):
         self.k.set_config_value('{}')
 
-    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', Mock(return_value=True))
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', create=True)
-    def test_touch_member(self):
+    def test_touch_member(self, mock_patch_namespaced_pod):
+        mock_patch_namespaced_pod.return_value.metadata.resource_version = '10'
         self.k.touch_member({'role': 'replica'})
         self.k._name = 'p-1'
         self.k.touch_member({'state': 'running', 'role': 'replica'})
@@ -83,46 +222,98 @@ class TestKubernetes(unittest.TestCase):
         self.k.initialize()
 
     def test_delete_leader(self):
-        self.k.delete_leader()
+        self.k.delete_leader(1)
 
     def test_cancel_initialization(self):
         self.k.cancel_initialization()
 
     @patch.object(k8s_client.CoreV1Api, 'delete_collection_namespaced_config_map',
-                  Mock(side_effect=k8s_client.rest.ApiException(403, '')))
+                  Mock(side_effect=k8s_client.rest.ApiException(403, '')), create=True)
     def test_delete_cluster(self):
         self.k.delete_cluster()
 
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints',
-                  Mock(side_effect=[k8s_client.rest.ApiException(502, ''), k8s_client.rest.ApiException(500, '')]))
-    def test_delete_sync_state(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10,
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
-        self.assertFalse(k.delete_sync_state())
-
     def test_watch(self):
         self.k.set_ttl(10)
         self.k.watch(None, 0)
         self.k.watch(None, 0)
-        with patch.object(k8s_watch.Watch, 'stream',
-                          Mock(side_effect=[Exception, [], KeyboardInterrupt,
-                                            [{'raw_object': {'metadata': {'resourceVersion': '2'}}}]])):
-            self.assertFalse(self.k.watch('1', 2))
-            self.assertRaises(KeyboardInterrupt, self.k.watch, '1', 2)
-            self.assertTrue(self.k.watch('1', 2))
 
     def test_set_history_value(self):
         self.k.set_history_value('{}')
 
-    @patch('kubernetes.config.load_kube_config', Mock())
+
-    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', Mock(return_value=True))
+class TestKubernetesEndpoints(BaseTestKubernetes):
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
+
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_endpoints', mock_list_namespaced_endpoints, create=True)
+    def setUp(self, config=None):
+        super(TestKubernetesEndpoints, self).setUp({'use_endpoints': True, 'pod_ip': '10.0.0.0'})
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints', create=True)
+    def test_update_leader(self, mock_patch_namespaced_endpoints):
+        self.assertIsNotNone(self.k.update_leader('123'))
+        args = mock_patch_namespaced_endpoints.call_args[0]
+        self.assertEqual(args[2].subsets[0].addresses[0].target_ref.resource_version, '10')
+        self.k._kinds._object_cache['test'].subsets[:] = []
+        self.assertIsNotNone(self.k.update_leader('123'))
+        self.k._kinds._object_cache['test'].metadata.annotations['leader'] = 'p-1'
+        self.assertFalse(self.k.update_leader('123'))
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints', mock_namespaced_kind, create=True)
+    def test_update_leader_with_restricted_access(self):
+        self.assertIsNotNone(self.k.update_leader('123', True))
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints', create=True)
+    def test__update_leader_with_retry(self, mock_patch):
+        mock_patch.side_effect = k8s_client.rest.ApiException(502, '')
+        self.assertFalse(self.k.update_leader('123'))
+        mock_patch.side_effect = RetryFailedError('')
+        self.assertFalse(self.k.update_leader('123'))
+        mock_patch.side_effect = k8s_client.rest.ApiException(409, '')
+        with patch('time.time', Mock(side_effect=[0, 100, 200])):
+            self.assertFalse(self.k.update_leader('123'))
+        with patch('time.sleep', Mock()):
+            self.assertFalse(self.k.update_leader('123'))
+            mock_patch.side_effect = [k8s_client.rest.ApiException(409, ''), mock_namespaced_kind()]
+            self.k._kinds._object_cache['test'].metadata.resource_version = '2'
+            self.assertIsNotNone(self.k._update_leader_with_retry({}, '1', []))
+
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints',
+                  Mock(side_effect=[k8s_client.rest.ApiException(500, ''),
+                                    k8s_client.rest.ApiException(502, '')]), create=True)
+    def test_delete_sync_state(self):
+        self.assertFalse(self.k.delete_sync_state())
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', mock_namespaced_kind, create=True)
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', mock_namespaced_kind, create=True)
     @patch.object(k8s_client.CoreV1Api, 'create_namespaced_service',
-                  Mock(side_effect=[True, False, k8s_client.rest.ApiException(500, '')]))
+                  Mock(side_effect=[True, False, k8s_client.rest.ApiException(500, '')]), create=True)
     def test__create_config_service(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10,
+        self.assertIsNotNone(self.k.patch_or_create_config({'foo': 'bar'}))
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
+        self.assertIsNotNone(self.k.patch_or_create_config({'foo': 'bar'}))
-        self.assertIsNotNone(k.patch_or_create_config({'foo': 'bar'}))
+        self.k.touch_member({'state': 'running', 'role': 'replica'})
-        self.assertIsNotNone(k.patch_or_create_config({'foo': 'bar'}))
+
-        k.touch_member({'state': 'running', 'role': 'replica'})
+
+class TestCacheBuilder(BaseTestKubernetes):
+
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map, create=True)
+    @patch('patroni.dcs.kubernetes.ObjectCache._watch')
+    def test__build_cache(self, mock_response):
+        mock_response.return_value.read_chunked.return_value = [json.dumps(
+            {'type': 'MODIFIED', 'object': {'metadata': {
+                'name': self.k.config_path, 'resourceVersion': '2', 'annotations': {self.k._CONFIG: 'foo'}}}}
+        ).encode('utf-8'), ('\n' + json.dumps(
+            {'type': 'DELETED', 'object': {'metadata': {
+                'name': self.k.config_path, 'resourceVersion': '3'}}}
+        ) + '\n' + json.dumps(
+            {'type': 'MDIFIED', 'object': {'metadata': {'name': self.k.config_path}}}
+        ) + '\n').encode('utf-8'), b'{"object":{', b'"code":410}}\n']
+        self.k._kinds._build_cache()
+
+    @patch('patroni.dcs.kubernetes.logger.error', Mock(side_effect=SleepException))
+    @patch('patroni.dcs.kubernetes.ObjectCache._build_cache', Mock(side_effect=Exception))
+    def test_run(self):
+        self.assertRaises(SleepException, self.k._pods.run)
+
+    @patch('time.sleep', Mock())
+    def test__list(self):
+        self.k._pods._func = Mock(side_effect=Exception)
+        self.assertRaises(Exception, self.k._pods._list)

tests/test_log.py

@@ -9,6 +9,8 @@ from patroni.config import Config
 from patroni.log import PatroniLogger
 from six.moves.queue import Queue, Full
 
+_LOG = logging.getLogger(__name__)
+
 
 class TestPatroniLogger(unittest.TestCase):
 
@@ -19,10 +21,10 @@ class TestPatroniLogger(unittest.TestCase):
         logging.getLogger().handlers[:] = self._handlers
 
     @patch('logging.FileHandler._open', Mock())
-    @patch('logging.Handler.close', Mock(side_effect=Exception))
     def test_patroni_logger(self):
         config = {
             'log': {
+                'traceback_level': 'DEBUG',
                 'max_queue_size': 5,
                 'dir': 'foo',
                 'file_size': 4096,
@@ -36,20 +38,25 @@ class TestPatroniLogger(unittest.TestCase):
         sys.argv = ['patroni.py']
         os.environ[Config.PATRONI_CONFIG_VARIABLE] = yaml.dump(config, default_flow_style=False)
         logger = PatroniLogger()
-        patroni_config = Config()
+        patroni_config = Config(None)
         logger.reload_config(patroni_config['log'])
+        _LOG.exception('test')
+        logger.start()
 
-        with patch.object(logging.Handler, 'format', Mock(side_effect=Exception)):
+        with patch.object(logging.Handler, 'format', Mock(side_effect=Exception)),\
+                patch('_pytest.logging.LogCaptureHandler.emit', Mock()):
             logging.error('test')
 
-        self.assertEqual(logger._log_handler.maxBytes, config['log']['file_size'])
+        self.assertEqual(logger.log_handler.maxBytes, config['log']['file_size'])
-        self.assertEqual(logger._log_handler.backupCount, config['log']['file_num'])
+        self.assertEqual(logger.log_handler.backupCount, config['log']['file_num'])
 
+        config['log']['level'] = 'DEBUG'
         config['log'].pop('dir')
+        with patch('logging.Handler.close', Mock(side_effect=Exception)):
             logger.reload_config(config['log'])
             with patch.object(logging.Logger, 'makeRecord',
                               Mock(side_effect=[logging.LogRecord('', logging.INFO, '', 0, '', (), None), Exception])):
-            logging.error('test')
+                logging.exception('test')
             logging.error('test')
             with patch.object(Queue, 'put_nowait', Mock(side_effect=Full)):
                 self.assertRaises(SystemExit, logger.shutdown)

tests/test_patroni.py

@@ -2,14 +2,14 @@ import etcd
 import logging
 import os
 import signal
-import sys
 import time
 import unittest
 
+import patroni.config as config
 from mock import Mock, PropertyMock, patch
 from patroni.api import RestApiServer
 from patroni.async_executor import AsyncExecutor
-from patroni.dcs.etcd import Client
+from patroni.dcs.etcd import AbstractEtcdClientWithFailover
 from patroni.exceptions import DCSError
 from patroni.postgresql import Postgresql
 from patroni.postgresql.config import ConfigHandler
@@ -39,23 +39,29 @@ class MockFrozenImporter(object):
 @patch.object(AsyncExecutor, 'run', Mock())
 @patch.object(etcd.Client, 'write', etcd_write)
 @patch.object(etcd.Client, 'read', etcd_read)
-@patch.object(Thread, 'start', Mock())
 class TestPatroni(unittest.TestCase):
 
-    @patch('pkgutil.get_importer', Mock(return_value=MockFrozenImporter()))
+    def test_no_config(self):
+        self.assertRaises(SystemExit, patroni_main)
+
+    @patch('sys.argv', ['patroni.py', '--validate-config', 'postgres0.yml'])
+    def test_validate_config(self):
+        self.assertRaises(SystemExit, patroni_main)
+
+    @patch('pkgutil.iter_importers', Mock(return_value=[MockFrozenImporter()]))
     @patch('sys.frozen', Mock(return_value=True), create=True)
     @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
     @patch.object(etcd.Client, 'read', etcd_read)
+    @patch.object(Thread, 'start', Mock())
+    @patch.object(AbstractEtcdClientWithFailover, 'machines', PropertyMock(return_value=['http://remotehost:2379']))
     def setUp(self):
         self._handlers = logging.getLogger().handlers[:]
         RestApiServer._BaseServer__is_shut_down = Mock()
         RestApiServer._BaseServer__shutdown_request = True
         RestApiServer.socket = 0
-        with patch.object(Client, 'machines') as mock_machines:
-            mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
-            sys.argv = ['patroni.py', 'postgres0.yml']
         os.environ['PATRONI_POSTGRESQL_DATA_DIR'] = 'data/test0'
-            self.p = Patroni()
+        conf = config.Config('postgres0.yml')
+        self.p = Patroni(conf)
 
     def tearDown(self):
         logging.getLogger().handlers[:] = self._handlers
@@ -66,19 +72,19 @@ class TestPatroni(unittest.TestCase):
         self.p.load_dynamic_configuration()
         self.p.load_dynamic_configuration()
 
+    @patch('sys.argv', ['patroni.py', 'postgres0.yml'])
     @patch('time.sleep', Mock(side_effect=SleepException))
     @patch.object(etcd.Client, 'delete', Mock())
-    @patch.object(Client, 'machines')
+    @patch.object(AbstractEtcdClientWithFailover, 'machines', PropertyMock(return_value=['http://remotehost:2379']))
     @patch.object(Thread, 'join', Mock())
-    def test_patroni_patroni_main(self, mock_machines):
+    def test_patroni_patroni_main(self):
         with patch('subprocess.call', Mock(return_value=1)):
-            sys.argv = ['patroni.py', 'postgres0.yml']
-
-            mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
             with patch.object(Patroni, 'run', Mock(side_effect=SleepException)):
+                os.environ['PATRONI_POSTGRESQL_DATA_DIR'] = 'data/test0'
                 self.assertRaises(SleepException, patroni_main)
             with patch.object(Patroni, 'run', Mock(side_effect=KeyboardInterrupt())):
                 with patch('patroni.ha.Ha.is_paused', Mock(return_value=True)):
+                    os.environ['PATRONI_POSTGRESQL_DATA_DIR'] = 'data/test0'
                     patroni_main()
 
     @patch('os.getpid')
@@ -122,8 +128,12 @@ class TestPatroni(unittest.TestCase):
         self.p.sighup_handler()
         self.p.ha.dcs.watch = Mock(side_effect=SleepException)
         self.p.api.start = Mock()
+        self.p.logger.start = Mock()
         self.p.config._dynamic_configuration = {}
         self.assertRaises(SleepException, self.p.run)
+        with patch('patroni.config.Config.reload_local_configuration', Mock(return_value=False)):
+            self.p.sighup_handler()
+            self.assertRaises(SleepException, self.p.run)
         with patch('patroni.config.Config.set_dynamic_configuration', Mock(return_value=True)):
             self.assertRaises(SleepException, self.p.run)
         with patch('patroni.postgresql.Postgresql.data_directory_empty', Mock(return_value=False)):
@@ -157,7 +167,7 @@ class TestPatroni(unittest.TestCase):
     def test_reload_config(self):
         self.p.reload_config()
         self.p.get_tags = Mock(side_effect=Exception)
-        self.p.reload_config()
+        self.p.reload_config(local=True)
 
     def test_nosync(self):
         self.p.tags['nosync'] = True
@@ -165,8 +175,10 @@ class TestPatroni(unittest.TestCase):
         self.p.tags['nosync'] = None
         self.assertFalse(self.p.nosync)
 
+    @patch.object(Thread, 'join', Mock())
     def test_shutdown(self):
         self.p.api.shutdown = Mock(side_effect=Exception)
+        self.p.ha.shutdown = Mock(side_effect=Exception)
         self.p.shutdown()
 
     def test_check_psycopg2(self):

tests/test_postgresql.py

@@ -1,13 +1,15 @@
 import mock  # for the mock.call method, importing it without a namespace breaks python3
 import os
+import psutil
 import psycopg2
+import re
 import subprocess
 import time
 
 from mock import Mock, MagicMock, PropertyMock, patch, mock_open
 from patroni.async_executor import CriticalTask
 from patroni.dcs import Cluster, ClusterConfig, Member, RemoteMember, SyncState
-from patroni.exceptions import PostgresConnectionException
+from patroni.exceptions import PostgresConnectionException, PatroniException
 from patroni.postgresql import Postgresql, STATE_REJECT, STATE_NO_RESPONSE
 from patroni.postgresql.postmaster import PostmasterProcess
 from patroni.postgresql.slots import SlotsHandler
@@ -90,17 +92,18 @@ class TestPostgresql(BaseTestPostgresql):
 
     @patch('subprocess.call', Mock(return_value=0))
     @patch('os.rename', Mock())
-    @patch.object(Postgresql, 'get_major_version', Mock(return_value=120000))
+    @patch('patroni.postgresql.CallbackExecutor', Mock())
+    @patch.object(Postgresql, 'get_major_version', Mock(return_value=130000))
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
     def setUp(self):
         super(TestPostgresql, self).setUp()
         self.p.config.write_postgresql_conf()
-        self.p._callback_executor = Mock()
 
     @patch('subprocess.Popen')
     @patch.object(Postgresql, 'wait_for_startup')
     @patch.object(Postgresql, 'wait_for_port_open')
     @patch.object(Postgresql, 'is_running')
+    @patch.object(Postgresql, 'controldata', Mock())
     def test_start(self, mock_is_running, mock_wait_for_port_open, mock_wait_for_startup, mock_popen):
         mock_is_running.return_value = MockPostmaster()
         mock_wait_for_port_open.return_value = True
@@ -131,6 +134,9 @@ class TestPostgresql(BaseTestPostgresql):
 
         self.p.cancellable.cancel()
         self.assertFalse(self.p.start())
+        with patch('patroni.postgresql.config.ConfigHandler.effective_configuration',
+                   PropertyMock(side_effect=Exception)):
+            self.assertIsNone(self.p.start())
 
     @patch.object(Postgresql, 'pg_isready')
     @patch('patroni.postgresql.polling_loop', Mock(return_value=range(1)))
@@ -171,6 +177,17 @@ class TestPostgresql(BaseTestPostgresql):
         mock_callback.assert_called()
         mock_postmaster.signal_stop.assert_called()
 
+        # Timed out waiting for fast shutdown triggers immediate shutdown
+        mock_postmaster.wait.side_effect = [psutil.TimeoutExpired(30), psutil.TimeoutExpired(30), Mock()]
+        mock_callback.reset_mock()
+        self.assertTrue(self.p.stop(on_safepoint=mock_callback, stop_timeout=30))
+        mock_callback.assert_called()
+        mock_postmaster.signal_stop.assert_called()
+
+        # Immediate shutdown succeeded
+        mock_postmaster.wait.side_effect = [psutil.TimeoutExpired(30), Mock()]
+        self.assertTrue(self.p.stop(on_safepoint=mock_callback, stop_timeout=30))
+
         # Stop signal failed
         mock_postmaster.signal_stop.return_value = False
         self.assertFalse(self.p.stop())
@@ -181,59 +198,86 @@ class TestPostgresql(BaseTestPostgresql):
         self.assertTrue(self.p.stop(on_safepoint=mock_callback))
         mock_callback.assert_called()
 
+        # Fast shutdown is timed out but when immediate postmaster is already gone
+        mock_postmaster.wait.side_effect = [psutil.TimeoutExpired(30), Mock()]
+        mock_postmaster.signal_stop.side_effect = [None, True]
+        self.assertTrue(self.p.stop(on_safepoint=mock_callback, stop_timeout=30))
+
     def test_restart(self):
         self.p.start = Mock(return_value=False)
         self.assertFalse(self.p.restart())
         self.assertEqual(self.p.state, 'restart failed (restarting)')
 
+    @patch('os.chmod', Mock())
     @patch.object(builtins, 'open', MagicMock())
     def test_write_pgpass(self):
-        self.p.write_pgpass({'host': 'localhost', 'port': '5432', 'user': 'foo'})
+        self.p.config.write_pgpass({'host': 'localhost', 'port': '5432', 'user': 'foo'})
-        self.p.write_pgpass({'host': 'localhost', 'port': '5432', 'user': 'foo', 'password': 'bar'})
+        self.p.config.write_pgpass({'host': 'localhost', 'port': '5432', 'user': 'foo', 'password': 'bar'})
 
     def test_checkpoint(self):
         with patch.object(MockCursor, 'fetchone', Mock(return_value=(True, ))):
             self.assertEqual(self.p.checkpoint({'user': 'postgres'}), 'is_in_recovery=true')
         with patch.object(MockCursor, 'execute', Mock(return_value=None)):
             self.assertIsNone(self.p.checkpoint())
-        self.assertEqual(self.p.checkpoint(), 'not accessible or not healty')
+        self.assertEqual(self.p.checkpoint(timeout=10), 'not accessible or not healty')
 
     @patch('patroni.postgresql.config.mtime', mock_mtime)
-    @patch.object(MockCursor, 'fetchone', Mock(side_effect=[('foo=bar',), ('',), ('',), ('a=b',)]))
+    @patch('patroni.postgresql.config.ConfigHandler._get_pg_settings')
-    def test_check_recovery_conf(self):
+    def test_check_recovery_conf(self, mock_get_pg_settings):
-        for version in (120000, 100000):
+        mock_get_pg_settings.return_value = {
-            with patch.object(Postgresql, 'major_version', PropertyMock(return_value=version)):
+            'primary_conninfo': ['primary_conninfo', 'foo=', None, 'string', 'postmaster', self.p.config._auto_conf],
-                self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': 'foo'})
+            'recovery_min_apply_delay': ['recovery_min_apply_delay', '0', 'ms', 'integer', 'sighup', 'foo']
-                self.assertFalse(self.p.config.check_recovery_conf(None))
+        }
-                self.p.config.write_recovery_conf({'primary_conninfo': 'foo'})
+        self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
-                self.p.config.write_postgresql_conf()
-                self.assertFalse(self.p.config.check_recovery_conf(None))
         self.p.config.write_recovery_conf({'standby_mode': 'on'})
-                self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
-                with patch('patroni.postgresql.config.ConfigHandler.primary_conninfo_params',
+        mock_get_pg_settings.return_value['primary_conninfo'][1] = ''
-                           Mock(return_value={'a': 'b'})):
+        mock_get_pg_settings.return_value['recovery_min_apply_delay'][1] = '1'
-                    self.assertFalse(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
-                    self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': 'a=b'})
+        mock_get_pg_settings.return_value['recovery_min_apply_delay'][5] = self.p.config._auto_conf
-                    self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (True, False))
+        mock_get_pg_settings.return_value['recovery_min_apply_delay'][1] = '0'
+        self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
+        conninfo = {'host': '1', 'password': 'bar'}
+        with patch('patroni.postgresql.config.ConfigHandler.primary_conninfo_params', Mock(return_value=conninfo)):
+            mock_get_pg_settings.return_value['recovery_min_apply_delay'][1] = '1'
+            self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
+            mock_get_pg_settings.return_value['primary_conninfo'][1] = 'host=1 passfile='\
+                + re.sub(r'([\'\\ ])', r'\\\1', self.p.config._pgpass)
+            mock_get_pg_settings.return_value['recovery_min_apply_delay'][1] = '0'
+            self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
+            self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': conninfo.copy()})
+            self.p.config.write_postgresql_conf()
+            self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
+            with patch.object(Postgresql, 'primary_conninfo', Mock(return_value='host=1')):
+                mock_get_pg_settings.return_value['primary_slot_name'] = [
+                    'primary_slot_name', '', '', 'string', 'postmaster', self.p.config._postgresql_conf]
+                self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
 
     @patch.object(Postgresql, 'major_version', PropertyMock(return_value=120000))
     @patch.object(Postgresql, 'is_running', MockPostmaster)
     @patch.object(MockPostmaster, 'create_time', Mock(return_value=1234567), create=True)
-    @patch.object(MockCursor, 'fetchone', Mock(return_value=('',)))
+    @patch('patroni.postgresql.config.ConfigHandler._get_pg_settings')
-    def test__read_primary_conninfo(self):
+    def test__read_recovery_params(self, mock_get_pg_settings):
-        self.p.config.write_recovery_conf({'standby_mode': 'on'})
+        mock_get_pg_settings.return_value = {'primary_conninfo': ['primary_conninfo', '', None, 'string',
+                                                                  'postmaster', self.p.config._postgresql_conf]}
+        self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': {'password': 'foo'}})
         self.p.config.write_postgresql_conf()
-        self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
-        self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
-        with patch.object(Postgresql, 'query', Mock(side_effect=Exception)),\
+        mock_get_pg_settings.side_effect = Exception
-                patch('patroni.postgresql.config.mtime', mock_mtime):
+        with patch('patroni.postgresql.config.mtime', mock_mtime):
-            self.assertFalse(self.p.config.check_recovery_conf(None))
+            self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
 
     @patch.object(Postgresql, 'major_version', PropertyMock(return_value=100000))
-    def test__read_primary_conninfo_pre_v12(self):
+    @patch.object(Postgresql, 'primary_conninfo', Mock(return_value='host=1'))
-        self.p.config.write_recovery_conf({'standby_mode': 'on'})
+    def test__read_recovery_params_pre_v12(self):
-        self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.p.config.write_recovery_conf({'standby_mode': 'off', 'primary_conninfo': {'password': 'foo'}})
-        self.assertTrue(self.p.config.check_recovery_conf(None))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
+        self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
+        self.p.config.write_recovery_conf({'restore_command': '\n'})
+        with patch('patroni.postgresql.config.mtime', mock_mtime):
+            self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
 
     def test_write_postgresql_and_sanitize_auto_conf(self):
         read_data = 'primary_conninfo = foo\nfoo = bar\n'
@@ -255,14 +299,14 @@ class TestPostgresql(BaseTestPostgresql):
     @patch.object(Postgresql, 'start', Mock())
     def test_follow(self):
         self.p.call_nowait('on_start')
-        m = RemoteMember('1', {'restore_command': '2', 'recovery_min_apply_delay': 3, 'archive_cleanup_command': '4'})
+        m = RemoteMember('1', {'restore_command': '2', 'primary_slot_name': 'foo', 'conn_kwargs': {'host': 'bar'}})
         self.p.follow(m)
 
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
     def test_sync_replication_slots(self):
         self.p.start()
-        config = ClusterConfig(1, {'slots': {'ls': {'database': 'a', 'plugin': 'b'},
+        config = ClusterConfig(1, {'slots': {'test_3': {'database': 'a', 'plugin': 'b'},
-                                             'A': 0, 'test_3': 0, 'b': {'type': 'logical', 'plugin': '1'}}}, 1)
+                                             'A': 0, 'ls': 0, 'b': {'type': 'logical', 'plugin': '1'}}}, 1)
         cluster = Cluster(True, config, self.leader, 0, [self.me, self.other, self.leadermem], None, None, None)
         with mock.patch('patroni.postgresql.Postgresql._query', Mock(side_effect=psycopg2.OperationalError)):
             self.p.slots_handler.sync_replication_slots(cluster)
@@ -298,6 +342,11 @@ class TestPostgresql(BaseTestPostgresql):
         with patch.object(Postgresql, '_query', Mock(side_effect=RetryFailedError(''))):
             self.assertRaises(PostgresConnectionException, self.p.is_leader)
 
+    @patch.object(Postgresql, 'controldata',
+                  Mock(return_value={'Database cluster state': 'shut down', 'Latest checkpoint location': 'X/678'}))
+    def test_latest_checkpoint_location(self):
+        self.assertIsNone(self.p.latest_checkpoint_location())
+
     def test_reload(self):
         self.assertTrue(self.p.reload())
 
@@ -308,13 +357,25 @@ class TestPostgresql(BaseTestPostgresql):
         mock_is_running.return_value = False
         self.assertFalse(self.p.is_healthy())
 
-    def test_promote(self):
+    @patch('psutil.Popen')
+    def test_promote(self, mock_popen):
+        mock_popen.return_value.wait.return_value = 0
+        task = CriticalTask()
+        self.assertTrue(self.p.promote(0, task))
+
         self.p.set_role('replica')
-        self.assertIsNone(self.p.promote(0))
+        self.p.config._config['pre_promote'] = 'test'
-        self.assertTrue(self.p.promote(0))
+        with patch('patroni.postgresql.cancellable.CancellableSubprocess.is_cancelled', PropertyMock(return_value=1)):
+            self.assertFalse(self.p.promote(0, task))
+
+        mock_popen.side_effect = Exception
+        self.assertFalse(self.p.promote(0, task))
+        task.reset()
+        task.cancel()
+        self.assertFalse(self.p.promote(0, task))
 
     def test_timeline_wal_position(self):
-        self.assertEqual(self.p.timeline_wal_position(), (1, 2))
+        self.assertEqual(self.p.timeline_wal_position(), (1, 2, 1))
         Thread(target=self.p.timeline_wal_position).start()
 
     @patch.object(PostmasterProcess, 'from_pidfile')
@@ -352,6 +413,10 @@ class TestPostgresql(BaseTestPostgresql):
 
     @patch('os.rename', Mock())
     @patch('os.path.isdir', Mock(return_value=True))
+    @patch('os.unlink', Mock())
+    @patch('os.symlink', Mock())
+    @patch('patroni.postgresql.Postgresql.pg_wal_realpath', Mock(return_value={'pg_wal': '/mnt/pg_wal'}))
+    @patch('patroni.postgresql.Postgresql.pg_tblspc_realpaths', Mock(return_value={'42': '/mnt/tablespaces/archive'}))
     def test_move_data_directory(self):
         self.p.move_data_directory()
         with patch('os.rename', Mock(side_effect=OSError)):
@@ -359,18 +424,21 @@ class TestPostgresql(BaseTestPostgresql):
 
     @patch('os.listdir', Mock(return_value=['recovery.conf']))
     @patch('os.path.exists', Mock(return_value=True))
+    @patch.object(Postgresql, 'controldata', Mock())
     def test_get_postgres_role_from_data_directory(self):
         self.assertEqual(self.p.get_postgres_role_from_data_directory(), 'replica')
 
     def test_remove_data_directory(self):
         def _symlink(src, dst):
-            try:
+            if os.name != 'nt':  # os.symlink under Windows needs admin rights skip it
                 os.symlink(src, dst)
-            except OSError:
+
-                if os.name == 'nt':  # os.symlink under Windows needs admin rights skip it
-                    pass
         os.makedirs(os.path.join(self.p.data_dir, 'foo'))
         _symlink('foo', os.path.join(self.p.data_dir, 'pg_wal'))
+        os.makedirs(os.path.join(self.p.data_dir, 'foo_tsp'))
+        pg_tblspc = os.path.join(self.p.data_dir, 'pg_tblspc')
+        os.makedirs(pg_tblspc)
+        _symlink('../foo_tsp', os.path.join(pg_tblspc, '12345'))
         self.p.remove_data_directory()
         open(self.p.data_dir, 'w').close()
         self.p.remove_data_directory()
@@ -421,13 +489,18 @@ class TestPostgresql(BaseTestPostgresql):
         self.p.config._config['foo'] = {'command': 'bar'}
         self.assertFalse(self.p.replica_method_can_work_without_replication_connection('foo'))
 
+    @patch('time.sleep', Mock())
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
-    def test_reload_config(self):
+    @patch.object(MockCursor, 'fetchone')
+    def test_reload_config(self, mock_fetchone):
+        mock_fetchone.return_value = (1,)
         parameters = self._PARAMETERS.copy()
         parameters.pop('f.oo')
+        parameters['wal_buffers'] = '512'
         config = {'pg_hba': [''], 'pg_ident': [''], 'use_unix_socket': True, 'authentication': {},
                   'retry_timeout': 10, 'listen': '*', 'krbsrvname': 'postgres', 'parameters': parameters}
         self.p.reload_config(config)
+        mock_fetchone.side_effect = Exception
         parameters['b.ar'] = 'bar'
         self.p.reload_config(config)
         parameters['autovacuum'] = 'on'
@@ -450,6 +523,10 @@ class TestPostgresql(BaseTestPostgresql):
     def test_postmaster_start_time(self):
         with patch.object(MockCursor, "fetchone", Mock(return_value=('foo', True, '', '', '', '', False))):
             self.assertEqual(self.p.postmaster_start_time(), 'foo')
+            t = Thread(target=self.p.postmaster_start_time)
+            t.start()
+            t.join()
+
         with patch.object(MockCursor, "execute", side_effect=psycopg2.Error):
             self.assertIsNone(self.p.postmaster_start_time())
 
@@ -532,36 +609,43 @@ class TestPostgresql(BaseTestPostgresql):
     def test_pick_sync_standby(self):
         cluster = Cluster(True, None, self.leader, 0, [self.me, self.other, self.leadermem], None,
                           SyncState(0, self.me.name, self.leadermem.name), None)
+        mock_cursor = Mock()
+        mock_cursor.fetchone.return_value = ('remote_apply',)
 
-        with patch.object(Postgresql, "query", return_value=[
+        with patch.object(Postgresql, "query", side_effect=[
-                    (self.leadermem.name, 'streaming', 'sync'),
+                    mock_cursor,
+                    [(self.leadermem.name, 'streaming', 'sync'),
                      (self.me.name, 'streaming', 'async'),
-                    (self.other.name, 'streaming', 'async'),
+                     (self.other.name, 'streaming', 'async')]
                 ]):
-            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, True))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), ([self.leadermem.name], [self.leadermem.name]))
 
-        with patch.object(Postgresql, "query", return_value=[
+        with patch.object(Postgresql, "query", side_effect=[
+                    mock_cursor,
+                    [(self.leadermem.name, 'streaming', 'potential'),
                      (self.me.name, 'streaming', 'async'),
-                    (self.leadermem.name, 'streaming', 'potential'),
+                     (self.other.name, 'streaming', 'async')]
-                    (self.other.name, 'streaming', 'async'),
                 ]):
-            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), ([self.leadermem.name], []))
 
-        with patch.object(Postgresql, "query", return_value=[
+        with patch.object(Postgresql, "query", side_effect=[
+                    mock_cursor,
+                    [(self.me.name, 'streaming', 'async'),
+                     (self.other.name, 'streaming', 'async')]
+                ]):
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), ([self.me.name], []))
+
+        with patch.object(Postgresql, "query", side_effect=[
+                    mock_cursor,
+                    [('missing', 'streaming', 'sync'),
                      (self.me.name, 'streaming', 'async'),
-                    (self.other.name, 'streaming', 'async'),
+                     (self.other.name, 'streaming', 'async')]
                 ]):
-            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), ([self.me.name], []))
 
-        with patch.object(Postgresql, "query", return_value=[
+        with patch.object(Postgresql, "query", side_effect=[mock_cursor, []]):
-                    ('missing', 'streaming', 'sync'),
+            self.p._major_version = 90400
-                    (self.me.name, 'streaming', 'async'),
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), ([], []))
-                    (self.other.name, 'streaming', 'async'),
-                ]):
-            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
-
-        with patch.object(Postgresql, "query", return_value=[]):
-            self.assertEqual(self.p.pick_synchronous_standby(cluster), (None, False))
 
     def test_set_sync_standby(self):
         def value_in_conf():
@@ -571,21 +655,21 @@ class TestPostgresql(BaseTestPostgresql):
                         return line.strip()
 
         mock_reload = self.p.reload = Mock()
-        self.p.config.set_synchronous_standby('n1')
+        self.p.config.set_synchronous_standby(['n1'])
         self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
         mock_reload.assert_called()
 
         mock_reload.reset_mock()
-        self.p.config.set_synchronous_standby('n1')
+        self.p.config.set_synchronous_standby(['n1'])
         mock_reload.assert_not_called()
         self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
 
-        self.p.config.set_synchronous_standby('n2')
+        self.p.config.set_synchronous_standby(['n1', 'n2'])
         mock_reload.assert_called()
-        self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n2'")
+        self.assertEqual(value_in_conf(), "synchronous_standby_names = '2 (n1,n2)'")
 
         mock_reload.reset_mock()
-        self.p.config.set_synchronous_standby(None)
+        self.p.config.set_synchronous_standby([])
         mock_reload.assert_called()
         self.assertEqual(value_in_conf(), None)
 
@@ -595,7 +679,7 @@ class TestPostgresql(BaseTestPostgresql):
         config['synchronous_mode_strict'] = True
         self.p.config.get_server_parameters(config)
         self.p.config.set_synchronous_standby('foo')
-        self.p.config.get_server_parameters(config)
+        self.assertTrue(str(self.p.config.get_server_parameters(config)).startswith('{'))
 
     @patch('time.sleep', Mock())
     def test__wait_for_connection_close(self):
@@ -615,44 +699,8 @@ class TestPostgresql(BaseTestPostgresql):
         mock_postmaster.signal_stop.assert_called()
         mock_postmaster.wait.assert_called()
 
-    def test_read_postmaster_opts(self):
-        m = mock_open(read_data='/usr/lib/postgres/9.6/bin/postgres "-D" "data/postgresql0" \
-"--listen_addresses=127.0.0.1" "--port=5432" "--hot_standby=on" "--wal_level=hot_standby" \
-"--wal_log_hints=on" "--max_wal_senders=5" "--max_replication_slots=5"\n')
-        with patch.object(builtins, 'open', m):
-            data = self.p.read_postmaster_opts()
-            self.assertEqual(data['wal_level'], 'hot_standby')
-            self.assertEqual(int(data['max_replication_slots']), 5)
-            self.assertEqual(data.get('D'), None)
-
-            m.side_effect = IOError
-            data = self.p.read_postmaster_opts()
-            self.assertEqual(data, dict())
-
-    @patch('subprocess.Popen')
-    def test_single_user_mode(self, subprocess_popen_mock):
-        subprocess_popen_mock.return_value.wait.return_value = 0
-        self.assertEqual(self.p.single_user_mode('CHECKPOINT', {'archive_mode': 'on'}), 0)
-
-    @patch('os.listdir', Mock(side_effect=[OSError, ['a', 'b']]))
-    @patch('os.unlink', Mock(side_effect=OSError))
-    @patch('os.remove', Mock())
-    @patch('os.path.islink', Mock(side_effect=[True, False]))
-    @patch('os.path.isfile', Mock(return_value=True))
-    def test_cleanup_archive_status(self):
-        self.p.cleanup_archive_status()
-        self.p.cleanup_archive_status()
-
-    @patch('os.unlink', Mock())
-    @patch('os.listdir', Mock(return_value=[]))
-    @patch('os.path.isfile', Mock(return_value=True))
-    @patch.object(Postgresql, 'read_postmaster_opts', Mock(return_value={}))
-    @patch.object(Postgresql, 'single_user_mode', Mock(return_value=0))
-    def test_fix_cluster_state(self):
-        self.assertTrue(self.p.fix_cluster_state())
-
     def test_replica_cached_timeline(self):
-        self.assertEqual(self.p.replica_cached_timeline(1), 2)
+        self.assertEqual(self.p.replica_cached_timeline(2), 3)
 
     def test_get_master_timeline(self):
         self.assertEqual(self.p.get_master_timeline(), 1)
@@ -662,9 +710,24 @@ class TestPostgresql(BaseTestPostgresql):
         with patch.object(Postgresql, 'controldata',
                           Mock(return_value={'max_connections setting': '200',
                                              'max_worker_processes setting': '20',
-                                             'max_prepared_xacts setting': '100',
                                              'max_locks_per_xact setting': '100',
                                              'max_wal_senders setting': 10})):
             self.p.cancellable.cancel()
             self.assertFalse(self.p.start())
             self.assertTrue(self.p.pending_restart)
+
+    @patch('os.path.exists', Mock(return_value=True))
+    @patch('os.path.isfile', Mock(return_value=False))
+    def test_pgpass_is_dir(self):
+        self.assertRaises(PatroniException, self.setUp)
+
+    @patch.object(Postgresql, '_query', Mock(side_effect=RetryFailedError('')))
+    def test_received_timeline(self):
+        self.p.set_role('standby_leader')
+        self.p.reset_cluster_info_state()
+        self.assertRaises(PostgresConnectionException, self.p.received_timeline)
+
+    def test__write_recovery_params(self):
+        self.p.config._write_recovery_params(Mock(), {'pause_at_recovery_target': 'false'})
+        with patch.object(Postgresql, 'major_version', PropertyMock(return_value=90400)):
+            self.p.config._write_recovery_params(Mock(), {'recovery_target_action': 'PROMOTE'})

tests/test_postmaster.py

@@ -1,3 +1,4 @@
+import multiprocessing
 import psutil
 import unittest
 
@@ -62,9 +63,42 @@ class TestPostmasterProcess(unittest.TestCase):
         mock_init.side_effect = None
         self.assertNotEqual(PostmasterProcess.from_pid(123), None)
 
+    @patch('psutil.Process.__init__', Mock())
+    @patch('psutil.wait_procs', Mock())
+    @patch('psutil.Process.suspend')
+    @patch('psutil.Process.children')
+    @patch('psutil.Process.kill')
+    def test_signal_kill(self, mock_kill, mock_children, mock_suspend):
+        proc = PostmasterProcess(123)
+
+        # all processes successfully stopped
+        mock_children.return_value = [Mock()]
+        mock_children.return_value[0].kill.side_effect = psutil.Error
+        self.assertTrue(proc.signal_kill())
+
+        # postmaster has gone before suspend
+        mock_suspend.side_effect = psutil.NoSuchProcess(123)
+        self.assertTrue(proc.signal_kill())
+
+        # postmaster has gone before we got a list of children
+        mock_suspend.side_effect = psutil.Error()
+        mock_children.side_effect = psutil.NoSuchProcess(123)
+        self.assertTrue(proc.signal_kill())
+
+        # postmaster has gone after we got a list of children
+        mock_children.side_effect = psutil.Error()
+        mock_kill.side_effect = psutil.NoSuchProcess(123)
+        self.assertTrue(proc.signal_kill())
+
+        # failed to kill postmaster
+        mock_kill.side_effect = psutil.AccessDenied(123)
+        self.assertFalse(proc.signal_kill())
+
     @patch('psutil.Process.__init__', Mock())
     @patch('psutil.Process.send_signal')
     @patch('psutil.Process.pid', Mock(return_value=123))
+    @patch('os.name', 'posix')
+    @patch('signal.SIGQUIT', 3, create=True)
     def test_signal_stop(self, mock_send_signal):
         proc = PostmasterProcess(-123)
         self.assertEqual(proc.signal_stop('immediate'), False)
@@ -75,6 +109,21 @@ class TestPostmasterProcess(unittest.TestCase):
         self.assertEqual(proc.signal_stop('immediate'), True)
         self.assertEqual(proc.signal_stop('immediate'), False)
 
+    @patch('psutil.Process.__init__', Mock())
+    @patch('patroni.postgresql.postmaster.os')
+    @patch('subprocess.call', Mock(side_effect=[0, OSError, 1]))
+    @patch('psutil.Process.pid', Mock(return_value=123))
+    @patch('psutil.Process.is_running', Mock(return_value=False))
+    def test_signal_stop_nt(self, mock_os):
+        mock_os.configure_mock(name="nt")
+        proc = PostmasterProcess(-123)
+        self.assertEqual(proc.signal_stop('immediate'), False)
+
+        proc = PostmasterProcess(123)
+        self.assertEqual(proc.signal_stop('immediate'), None)
+        self.assertEqual(proc.signal_stop('immediate'), False)
+        self.assertEqual(proc.signal_stop('immediate'), True)
+
     @patch('psutil.Process.__init__', Mock())
     @patch('psutil.wait_procs')
     def test_wait_for_user_backends_to_close(self, mock_wait):
@@ -96,6 +145,7 @@ class TestPostmasterProcess(unittest.TestCase):
     @patch('subprocess.Popen')
     @patch('os.setsid', Mock(), create=True)
     @patch('multiprocessing.Process', MockProcess)
+    @patch('multiprocessing.get_context', Mock(return_value=multiprocessing), create=True)
     @patch.object(PostmasterProcess, 'from_pid')
     @patch.object(PostmasterProcess, '_from_pidfile')
     def test_start(self, mock_frompidfile, mock_frompid, mock_popen):

tests/test_raft.py

@@ -0,0 +1,155 @@
+import os
+import unittest
+import time
+
+from mock import Mock, patch
+from patroni.dcs.raft import DynMemberSyncObj, KVStoreTTL, Raft, SyncObjUtility
+from pysyncobj import SyncObjConf, FAIL_REASON
+
+
+def remove_files(prefix):
+    for f in ('journal', 'dump'):
+        f = prefix + f
+        if os.path.isfile(f):
+            for i in range(0, 15):
+                try:
+                    if os.path.isfile(f):
+                        os.unlink(f)
+                        break
+                    else:
+                        break
+                except Exception:
+                    time.sleep(1.0)
+
+
+@patch('pysyncobj.tcp_server.TcpServer.bind', Mock())
+class TestDynMemberSyncObj(unittest.TestCase):
+
+    @patch('pysyncobj.tcp_server.TcpServer.bind', Mock())
+    def setUp(self):
+        self.conf = SyncObjConf(appendEntriesUseBatch=False, dynamicMembershipChange=True, autoTick=False)
+        self.so = DynMemberSyncObj('127.0.0.1:1234', ['127.0.0.1:1235'], self.conf)
+
+    @patch.object(SyncObjUtility, 'sendMessage')
+    def test_add_member(self, mock_send_message):
+        mock_send_message.return_value = [{'addr': '127.0.0.1:1235'}, {'addr': '127.0.0.1:1236'}]
+        mock_send_message.ver = 0
+        DynMemberSyncObj('127.0.0.1:1234', ['127.0.0.1:1235'], self.conf)
+        self.conf.dynamicMembershipChange = False
+        DynMemberSyncObj('127.0.0.1:1234', ['127.0.0.1:1235'], self.conf)
+
+    def test___onUtilityMessage(self):
+        self.so._SyncObj__encryptor = Mock()
+        mock_conn = Mock()
+        mock_conn.sendRandKey = None
+        self.so._SyncObj__transport._onIncomingMessageReceived(mock_conn, 'randkey')
+        self.so._SyncObj__transport._onIncomingMessageReceived(mock_conn, ['members'])
+        self.so._SyncObj__transport._onIncomingMessageReceived(mock_conn, ['status'])
+
+    def test__SyncObj__doChangeCluster(self):
+        self.so._SyncObj__doChangeCluster(['add', '127.0.0.1:1236'])
+
+    def test_utility(self):
+        utility = SyncObjUtility(['127.0.0.1:1235'], self.conf)
+        utility.setPartnerNode(list(utility._SyncObj__otherNodes)[0])
+        utility.sendMessage(['members'])
+        utility._onMessageReceived(0, '')
+
+
+class TestKVStoreTTL(unittest.TestCase):
+
+    def setUp(self):
+        self.conf = SyncObjConf(appendEntriesUseBatch=False, appendEntriesPeriod=0.001,
+                                raftMinTimeout=0.004, raftMaxTimeout=0.005, autoTickPeriod=0.001)
+        callback = Mock()
+        callback.replicated = False
+        self.so = KVStoreTTL('127.0.0.1:1234', [], self.conf, on_set=callback, on_delete=callback)
+        self.so.set_retry_timeout(10)
+
+    @staticmethod
+    def destroy(so):
+        so.destroy()
+        so._SyncObj__thread.join()
+
+    def tearDown(self):
+        if self.so:
+            self.destroy(self.so)
+
+    def test_set(self):
+        self.assertTrue(self.so.set('foo', 'bar', prevExist=False, ttl=30))
+        self.assertFalse(self.so.set('foo', 'bar', prevExist=False, ttl=30))
+        self.assertFalse(self.so.retry(self.so._set, 'foo', {'value': 'buz', 'created': 1, 'updated': 1}, prevValue=''))
+        self.assertTrue(self.so.retry(self.so._set, 'foo', {'value': 'buz', 'created': 1, 'updated': 1}))
+
+    def test_delete(self):
+        self.conf.autoTickPeriod = 0.1
+        self.so.set('foo', 'bar')
+        self.so.set('fooo', 'bar')
+        self.assertFalse(self.so.delete('foo', prevValue='buz'))
+        self.assertFalse(self.so.delete('foo', prevValue='bar', timeout=0.00001))
+        self.assertFalse(self.so.delete('foo', prevValue='bar'))
+        self.assertTrue(self.so.delete('foo', recursive=True))
+        self.assertFalse(self.so.retry(self.so._delete, 'foo', prevValue=''))
+
+    def test_expire(self):
+        self.so.set('foo', 'bar', ttl=0.001)
+        time.sleep(1)
+        self.assertIsNone(self.so.get('foo'))
+        self.assertEqual(self.so.get('foo', recursive=True), {})
+
+    @patch('time.sleep', Mock())
+    def test_retry(self):
+        return_values = [FAIL_REASON.QUEUE_FULL, FAIL_REASON.SUCCESS, FAIL_REASON.REQUEST_DENIED]
+
+        def test(callback):
+            callback(True, return_values.pop(0))
+        self.assertTrue(self.so.retry(test))
+        self.assertFalse(self.so.retry(test))
+
+    def test_on_ready_override(self):
+        self.assertTrue(self.so.set('foo', 'bar'))
+        self.destroy(self.so)
+        self.so = None
+        self.conf.onReady = Mock()
+        self.conf.autoTick = False
+        so = KVStoreTTL('127.0.0.1:1234', ['127.0.0.1:1235'], self.conf)
+        so.doTick(0)
+        so.destroy()
+
+
+class TestRaft(unittest.TestCase):
+
+    def test_raft(self):
+        raft = Raft({'ttl': 30, 'scope': 'test', 'name': 'pg', 'self_addr': '127.0.0.1:1234', 'retry_timeout': 10})
+        raft.set_retry_timeout(20)
+        raft.set_ttl(60)
+        self.assertTrue(raft.touch_member(''))
+        self.assertTrue(raft.initialize())
+        self.assertTrue(raft.cancel_initialization())
+        self.assertTrue(raft.set_config_value('{}'))
+        self.assertTrue(raft.write_sync_state('foo', 'bar'))
+        self.assertTrue(raft.update_leader('1'))
+        self.assertTrue(raft.manual_failover('foo', 'bar'))
+        raft.get_cluster()
+        self.assertTrue(raft.delete_sync_state())
+        self.assertTrue(raft.delete_leader())
+        self.assertTrue(raft.set_history_value(''))
+        self.assertTrue(raft.delete_cluster())
+        raft.get_cluster()
+        self.assertTrue(raft.take_leader())
+        raft.watch(None, 0.001)
+        raft._sync_obj.destroy()
+        raft._sync_obj._SyncObj__thread.join()
+
+    def tearDown(self):
+        remove_files('127.0.0.1:1234.')
+
+    def setUp(self):
+        self.tearDown()
+
+    @patch('patroni.dcs.raft.KVStoreTTL')
+    @patch('threading.Event')
+    def test_init(self, mock_event, mock_kvstore):
+        mock_kvstore.return_value.applied_local_log = False
+        mock_event.return_value.isSet.side_effect = [False, True]
+        self.assertIsNotNone(Raft({'ttl': 30, 'scope': 'test', 'name': 'pg', 'patronictl': True}))

tests/test_raft_controller.py

@@ -0,0 +1,44 @@
+import logging
+import os
+import unittest
+
+from mock import Mock, patch
+from pysyncobj import SyncObj
+from patroni.config import Config
+from patroni.raft_controller import RaftController, main as _main
+
+from . import SleepException
+from .test_raft import remove_files
+
+
+class TestPatroniRaftController(unittest.TestCase):
+
+    SELF_ADDR = '127.0.0.1:5360'
+
+    def remove_files(self):
+        remove_files(self.SELF_ADDR + '.')
+
+    @patch('pysyncobj.tcp_server.TcpServer.bind', Mock())
+    def setUp(self):
+        self._handlers = logging.getLogger().handlers[:]
+        self.remove_files()
+        os.environ['PATRONI_RAFT_SELF_ADDR'] = self.SELF_ADDR
+        config = Config('postgres0.yml', validator=None)
+        self.rc = RaftController(config)
+
+    def tearDown(self):
+        logging.getLogger().handlers[:] = self._handlers
+        self.remove_files()
+
+    def test_reload_config(self):
+        self.rc.reload_config()
+
+    @patch('logging.Logger.error', Mock(side_effect=SleepException))
+    @patch.object(SyncObj, 'doTick', Mock(side_effect=Exception))
+    def test_run(self):
+        self.assertRaises(SleepException, self.rc.run)
+        self.rc.shutdown()
+
+    @patch('sys.argv', ['patroni'])
+    def test_patroni_raft_controller_main(self):
+        self.assertRaises(SystemExit, _main)

tests/test_rewind.py

@@ -1,12 +1,45 @@
-from mock import Mock, PropertyMock, patch
+from mock import Mock, PropertyMock, patch, mock_open
 
 from patroni.postgresql import Postgresql
 from patroni.postgresql.cancellable import CancellableSubprocess
 from patroni.postgresql.rewind import Rewind
+from six.moves import builtins
 
 from . import BaseTestPostgresql, MockCursor, psycopg2_connect
 
 
+class MockThread(object):
+
+    def __init__(self, target, args):
+        self._target = target
+        self._args = args
+
+    def start(self):
+        self._target(*self._args)
+
+
+def mock_cancellable_call(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'pg_rewind: error: could not open file ' +
+                                              b'"data/postgresql0/pg_xlog/000000010000000000000003": No such file')
+    return 1
+
+
+def mock_cancellable_call0(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'')
+    return 0
+
+
+def mock_cancellable_call1(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'')
+    return 1
+
+
 @patch('subprocess.call', Mock(return_value=0))
 @patch('psycopg2.connect', psycopg2_connect)
 class TestRewind(BaseTestPostgresql):
@@ -25,12 +58,22 @@ class TestRewind(BaseTestPostgresql):
         self.p.config._config['use_pg_rewind'] = False
         self.assertFalse(self.r.can_rewind)
 
-    @patch.object(CancellableSubprocess, 'call')
+    def test_pg_rewind(self):
-    def test_pg_rewind(self, mock_cancellable_subprocess_call):
         r = {'user': '', 'host': '', 'port': '', 'database': '', 'password': ''}
-        mock_cancellable_subprocess_call.return_value = 0
+        with patch.object(Postgresql, 'major_version', PropertyMock(return_value=130000)),\
+                patch.object(CancellableSubprocess, 'call', Mock(return_value=None)):
+            with patch('subprocess.check_output', Mock(return_value=b'boo')):
+                self.assertFalse(self.r.pg_rewind(r))
+            with patch('subprocess.check_output', Mock(side_effect=Exception)):
+                self.assertFalse(self.r.pg_rewind(r))
+
+        with patch.object(Postgresql, 'major_version', PropertyMock(return_value=120000)),\
+                patch('subprocess.check_output', Mock(return_value=b'foo %f %p %r %% % %')):
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call):
+                self.assertFalse(self.r.pg_rewind(r))
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call0):
                 self.assertTrue(self.r.pg_rewind(r))
-        mock_cancellable_subprocess_call.side_effect = OSError
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call1):
                 self.assertFalse(self.r.pg_rewind(r))
 
     @patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
@@ -39,14 +82,15 @@ class TestRewind(BaseTestPostgresql):
         with patch.object(Postgresql, 'controldata',
                           Mock(return_value={'Database cluster state': 'shut down in recovery',
                                              'Minimum recovery ending location': '0/0',
-                                             "Min recovery ending loc's timeline": '0'})):
+                                             "Min recovery ending loc's timeline": '0',
+                                             'Latest checkpoint location': '0/'})):
             self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
 
         with patch.object(Postgresql, 'is_running', Mock(return_value=True)):
-            with patch.object(MockCursor, 'fetchone', Mock(side_effect=[(False, ), Exception])):
+            with patch.object(MockCursor, 'fetchone', Mock(side_effect=[(0, 0, 1, 1,), Exception])):
                 self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
 
-    @patch.object(CancellableSubprocess, 'call', Mock(return_value=0))
+    @patch.object(CancellableSubprocess, 'call', mock_cancellable_call)
     @patch.object(Postgresql, 'checkpoint', side_effect=['', '1'],)
     @patch.object(Postgresql, 'stop', Mock(return_value=False))
     @patch.object(Postgresql, 'start', Mock())
@@ -72,11 +116,19 @@ class TestRewind(BaseTestPostgresql):
         with patch.object(Postgresql, 'is_running', Mock(return_value=True)):
             self.r.execute(self.leader)
 
+    @patch('patroni.postgresql.rewind.logger.info')
+    def test__log_master_history(self, mock_logger):
+        history = [[n, n, ''] for n in range(1, 10)]
+        self.r._log_master_history(history, 1)
+        expected = '\n'.join(['{0}\t0/{0}\t'.format(n) for n in range(1, 4)] + ['...', '9\t0/9\t'])
+        self.assertEqual(mock_logger.call_args[0][1], expected)
+
     @patch.object(Postgresql, 'start', Mock())
     @patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
-    @patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(2, '40159C1')))
+    @patch.object(Rewind, '_get_local_timeline_lsn')
     @patch.object(Rewind, 'check_leader_is_not_in_recovery')
-    def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery):
+    def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery, mock_get_local_timeline_lsn):
+        mock_get_local_timeline_lsn.return_value = (True, 2, 67197377)
         mock_check_leader_is_not_in_recovery.return_value = False
         self.r.trigger_check_diverged_lsn()
         self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
@@ -88,20 +140,91 @@ class TestRewind(BaseTestPostgresql):
         with patch('psycopg2.connect', Mock(side_effect=Exception)):
             self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.r.trigger_check_diverged_lsn()
-        with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 2, '0/0'), ('', b'3\t0/40159C0\tn\n')])):
+        with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 3, '0/0'), ('', b'3\t0/40159C0\tn\n')])):
             self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.r.trigger_check_diverged_lsn()
         with patch.object(MockCursor, 'fetchone', Mock(return_value=('', 1, '0/0'))):
-            with patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(1, '0/0'))):
+            with patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(True, 1, '0/0'))):
                 self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
             self.r.trigger_check_diverged_lsn()
             self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
 
+        self.r.reset_state()
+        self.r.trigger_check_diverged_lsn()
+        mock_get_local_timeline_lsn.return_value = (False, 2, 67296664)
+        self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+
+        with patch('subprocess.Popen') as mock_popen:
+            mock_popen.return_value.communicate.return_value = (
+                b'0, lsn: 0/040159C1, prev 0/\n',
+                b'pg_waldump: fatal: error in WAL record at 0/40159C1: invalid record length at /: wanted 24, got 0\n'
+            )
+            self.r.reset_state()
+            self.r.trigger_check_diverged_lsn()
+            mock_get_local_timeline_lsn.return_value = (False, 2, 67197377)
+            self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+            self.r.reset_state()
+            self.r.trigger_check_diverged_lsn()
+            mock_popen.side_effect = Exception
+            self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+
     @patch.object(MockCursor, 'fetchone', Mock(side_effect=[(True,), Exception]))
     def test_check_leader_is_not_in_recovery(self):
         self.r.check_leader_is_not_in_recovery()
         self.r.check_leader_is_not_in_recovery()
 
-    @patch.object(Postgresql, 'controldata', Mock(return_value={"Latest checkpoint's TimeLineID": 1}))
+    def test_read_postmaster_opts(self):
-    def test_check_for_checkpoint_after_promote(self):
+        m = mock_open(read_data='/usr/lib/postgres/9.6/bin/postgres "-D" "data/postgresql0" \
-        self.r.check_for_checkpoint_after_promote()
+"--listen_addresses=127.0.0.1" "--port=5432" "--hot_standby=on" "--wal_level=hot_standby" \
+"--wal_log_hints=on" "--max_wal_senders=5" "--max_replication_slots=5"\n')
+        with patch.object(builtins, 'open', m):
+            data = self.r.read_postmaster_opts()
+            self.assertEqual(data['wal_level'], 'hot_standby')
+            self.assertEqual(int(data['max_replication_slots']), 5)
+            self.assertEqual(data.get('D'), None)
+
+            m.side_effect = IOError
+            data = self.r.read_postmaster_opts()
+            self.assertEqual(data, dict())
+
+    @patch('psutil.Popen')
+    def test_single_user_mode(self, subprocess_popen_mock):
+        subprocess_popen_mock.return_value.wait.return_value = 0
+        subprocess_popen_mock.return_value.communicate.return_value = ('', '')
+        self.assertEqual(self.r.single_user_mode({'input': 'CHECKPOINT'}, {'archive_mode': 'on'}), 0)
+
+    @patch('os.listdir', Mock(side_effect=[OSError, ['a', 'b']]))
+    @patch('os.unlink', Mock(side_effect=OSError))
+    @patch('os.remove', Mock())
+    @patch('os.path.islink', Mock(side_effect=[True, False]))
+    @patch('os.path.isfile', Mock(return_value=True))
+    def test_cleanup_archive_status(self):
+        self.r.cleanup_archive_status()
+        self.r.cleanup_archive_status()
+
+    @patch('os.unlink', Mock())
+    @patch('os.listdir', Mock(return_value=[]))
+    @patch('os.path.isfile', Mock(return_value=True))
+    @patch.object(Rewind, 'read_postmaster_opts', Mock(return_value={}))
+    @patch.object(Rewind, 'single_user_mode', Mock(return_value=0))
+    def test_ensure_clean_shutdown(self):
+        self.assertTrue(self.r.ensure_clean_shutdown())
+
+    @patch('patroni.postgresql.rewind.Thread', MockThread)
+    @patch.object(Postgresql, 'controldata')
+    @patch.object(Postgresql, 'checkpoint')
+    def test_ensure_checkpoint_after_promote(self, mock_checkpoint, mock_controldata):
+        mock_checkpoint.return_value = None
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())
+
+        self.r.reset_state()
+        mock_controldata.return_value = {"Latest checkpoint's TimeLineID": 1}
+        mock_checkpoint.side_effect = Exception
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())
+
+        self.r.reset_state()
+        mock_controldata.side_effect = TypeError
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())