Release 1.5.6 (#1020)

* Update release notes
* Bump version

.gitignore

@@ -51,3 +51,9 @@ scm-source.json
 docs/build/
 docs/source/_static/
 docs/source/_templates/
+
+# Pycharm IDE
+.idea/
+
+#VSCode IDE
+.vscode/

.travis.yml

@@ -1,6 +1,10 @@
 sudo: true
 dist: trusty
 language: python
+addons:
+  apt:
+    packages:
+      - expect-dev # for unbuffer
 env:
   global:
   - ETCDVERSION=3.0.17 ZKVERSION=3.4.11 CONSULVERSION=0.7.4
@@ -131,13 +135,13 @@ script:
 
         if [[ $TEST_SUITE != "behave" ]]; then
             echo Running unit tests using python${pv}
-            $TEST_SUITE test
+            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 $TEST_SUITE; then
+            if ! PATH=.:/usr/lib/postgresql/9.6/bin:$PATH unbuffer $TEST_SUITE; then
                 # output all log files when tests are failing
-                grep . features/output/*/*postgres?.*
+                grep . features/output/*_failed/*postgres?.*
                 exit 1
             fi
         fi

.zappr.yaml

@@ -1,13 +0,0 @@
-# for github.com
-approvals:
-  groups:
-    zalando:
-      minimum: 2
-      from:
-        orgs:
-          - "zalando"
-# team should be valid team id in team service https://teams.auth.zalando.com/api/teams/:id
-X-Zalando-Team: "acid"
-# type should be one of [code, doc, config, tools, secrets]
-# code will be the default value, if X-Zalando-Type is not found in .zappr.yml
-X-Zalando-Type: code

Dockerfile

@@ -1,45 +1,156 @@
 ## This Dockerfile is meant to aid in the building and debugging patroni whilst developing on your local machine
 ## It has all the necessary components to play/debug with a single node appliance, running etcd
-FROM postgres:10
-MAINTAINER Alexander Kukushkin <[email protected]>
+ARG PG_MAJOR=10
+ARG COMPRESS=false
+ARG PGHOME=/home/postgres
+ARG PGDATA=$PGHOME/data
+ARG LC_ALL=C.UTF-8
+ARG LANG=C.UTF-8
 
-RUN export DEBIAN_FRONTEND=noninteractive \
+FROM postgres:$PG_MAJOR as builder
+
+ARG PGHOME
+ARG PGDATA
+ARG LC_ALL
+ARG LANG
+
+ENV ETCDVERSION=2.3.8 CONFDVERSION=0.16.0
+
+RUN set -ex \
+    && export DEBIAN_FRONTEND=noninteractive \
     && echo 'APT::Install-Recommends "0";\nAPT::Install-Suggests "0";' > /etc/apt/apt.conf.d/01norecommend \
     && apt-get update -y \
-    && apt-get upgrade -y \
-    # postgres:10 is based on debian, which has patroni package. We will install all required dependencies
-    && apt-get install -s patroni | sed -n -e '/^Inst patroni /d' -e 's/^Inst \([^ ]\+\) .*$/\1/p' \
-            | xargs apt-get install -y curl jq haproxy locales python3-etcd python3-kazoo \
-
-    ## Make sure we have a en_US.UTF-8 locale available
+    # postgres:10 is based on debian, which has the patroni package. We will install all required dependencies
+    && apt-cache depends patroni | sed -n -e 's/.*Depends: \(python3-.\+\)$/\1/p' \
+            | 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 \
+    && 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 \
+    && echo 'en_US.UTF-8 UTF-8' > /usr/share/i18n/SUPPORTED \
+\
+    # Make sure we have a en_US.UTF-8 locale available
     && localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8 \
-
-    && mkdir -p /home/postgres \
-    && chown postgres:postgres /home/postgres \
-
-    # Clean up
-    && apt-get purge -y libpython2.7-stdlib libpython2.7-minimal \
+\
+    # haproxy dummy config
+    && echo 'global\n        stats socket /run/haproxy/admin.sock mode 660 level admin' > /etc/haproxy/haproxy.cfg \
+\
+    # vim config
+    && echo 'syntax on\nfiletype plugin indent on\nset mouse-=a\nautocmd FileType yaml setlocal ts=2 sts=2 sw=2 expandtab' > /etc/vim/vimrc.local \
+\
+    # Prepare postgres/patroni/haproxy environment
+    && mkdir -p $PGHOME/.config/patroni /patroni /run/haproxy \
+    && ln -s ../../patroni.yaml $PGHOME/.config/patroni/patronictl.yaml \
+    && ln -s /patronictl.py /usr/local/bin/patronictl \
+    && sed -i "s|/var/lib/postgresql.*|$PGHOME:/bin/bash|" /etc/passwd \
+    && chown -R postgres:postgres /var/log \
+\
+    # Download etcd
+    && curl -sL https://github.com/coreos/etcd/releases/download/v${ETCDVERSION}/etcd-v${ETCDVERSION}-linux-amd64.tar.gz \
+            | tar xz -C /usr/local/bin --strip=1 --wildcards --no-anchored etcd etcdctl \
+\
+    # Download confd
+    && curl -sL https://github.com/kelseyhightower/confd/releases/download/v${CONFDVERSION}/confd-${CONFDVERSION}-linux-amd64 \
+            > /usr/local/bin/confd && chmod +x /usr/local/bin/confd \
+\
+    # Clean up all useless packages and some files
+    && apt-get purge -y --allow-remove-essential python3-pip gzip bzip2 util-linux e2fsprogs \
+                libmagic1 bsdmainutils login ncurses-bin libmagic-mgc e2fslibs bsdutils \
+                exim4-config gnupg-agent dirmngr libpython2.7-stdlib libpython2.7-minimal \
     && apt-get autoremove -y \
     && apt-get clean -y \
-    && rm -rf /var/lib/apt/lists/* /root/.cache
+    && rm -rf /var/lib/apt/lists/* \
+        /root/.cache \
+        /var/cache/debconf/* \
+        /etc/rc?.d \
+        /etc/systemd \
+        /docker-entrypoint* \
+        /sbin/pam* \
+        /sbin/swap* \
+        /sbin/unix* \
+        /usr/local/bin/gosu \
+        /usr/sbin/[acgipr]* \
+        /usr/sbin/*user* \
+        /usr/share/doc* \
+        /usr/share/man \
+        /usr/share/info \
+        /usr/share/i18n/locales/translit_hangul \
+        /usr/share/locale/?? \
+        /usr/share/locale/??_?? \
+        /usr/share/postgresql/*/man \
+        /usr/share/postgresql-common/pg_wrapper \
+        /usr/share/vim/vim80/doc \
+        /usr/share/vim/vim80/lang \
+        /usr/share/vim/vim80/tutor \
+#        /var/lib/dpkg/info/* \
+    && find /usr/bin -xtype l -delete \
+    && find /var/log -type f -exec truncate --size 0 {} \; \
+    && find /usr/lib/python3/dist-packages -name '*test*' | xargs rm -fr \
+    && find /lib/x86_64-linux-gnu/security -type f ! -name pam_env.so ! -name pam_permit.so ! -name pam_unix.so -delete
 
-ENV ETCDVERSION 3.2.23
-RUN curl -L https://github.com/coreos/etcd/releases/download/v${ETCDVERSION}/etcd-v${ETCDVERSION}-linux-amd64.tar.gz \
-    | tar xz -C /usr/local/bin --strip=1 --wildcards --no-anchored etcd etcdctl
+# perform compression if it is necessary
+ARG COMPRESS
+RUN if [ "$COMPRESS" = "true" ]; then \
+        set -ex \
+        # Allow certain sudo commands from postgres
+        && echo 'postgres ALL=(ALL) NOPASSWD: /bin/tar xpJf /a.tar.xz -C /, /bin/rm /a.tar.xz, /bin/ln -snf dash /bin/sh' >> /etc/sudoers \
+        && ln -snf busybox /bin/sh \
+        && files="/bin/sh /usr/bin/sudo /usr/lib/sudo/sudoers.so /lib/x86_64-linux-gnu/security/pam_*.so" \
+        && libs="$(ldd $files | awk '{print $3;}' | grep '^/' | sort -u) /lib/x86_64-linux-gnu/ld-linux-x86-64.so.* /lib/x86_64-linux-gnu/libnsl.so.* /lib/x86_64-linux-gnu/libnss_compat.so.*" \
+        && (echo /var/run $files $libs | tr ' ' '\n' && realpath $files $libs) | sort -u | sed 's/^\///' > /exclude \
+        && find /etc/alternatives -xtype l -delete \
+        && save_dirs="usr lib var bin sbin etc/ssl etc/init.d etc/alternatives etc/apt" \
+        && XZ_OPT=-e9v tar -X /exclude -cpJf a.tar.xz $save_dirs \
+        # we call "cat /exclude" to avoid including files from the $save_dirs that are also among
+        # the exceptions listed in the /exclude, as "uniq -u" eliminates all non-unique lines.
+        # By calling "cat /exclude" a second time we guarantee that there will be at least two lines
+        # for each exception and therefore they will be excluded from the output passed to 'rm'.
+        && /bin/busybox sh -c "(find $save_dirs -not -type d && cat /exclude /exclude && echo exclude) | sort | uniq -u | xargs /bin/busybox rm" \
+        && /bin/busybox --install -s \
+        && /bin/busybox sh -c "find $save_dirs -type d -depth -exec rmdir -p {} \; 2> /dev/null"; \
+    fi
 
-ENV CONFDVERSION 0.16.0
-RUN curl -L https://github.com/kelseyhightower/confd/releases/download/v${CONFDVERSION}/confd-${CONFDVERSION}-linux-amd64 > /usr/local/bin/confd \
-    && chmod +x /usr/local/bin/confd
+FROM scratch
+COPY --from=builder / /
 
-ADD patronictl.py patroni.py docker/entrypoint.sh /
-ADD patroni /patroni/
-ADD extras/confd /etc/confd
+LABEL maintainer="Alexander Kukushkin <[email protected]>"
 
-RUN sed -i 's/env python/&3/' patroni*.py && ln -s /patronictl.py /usr/local/bin/patronictl && mkdir /data/ /run/haproxy \
-    && touch /pgpass /patroni.yml && chown postgres:postgres -R /patroni/ /data/ /pgpass /patroni.yml /etc/haproxy /var/run/ /var/lib/ /var/log/
+ARG PG_MAJOR
+ARG COMPRESS
+ARG PGHOME
+ARG PGDATA
+ARG LC_ALL
+ARG LANG
 
-EXPOSE 2379 5432 8008
+ARG PGBIN=/usr/lib/postgresql/$PG_MAJOR/bin
+
+ENV LC_ALL=$LC_ALL LANG=$LANG EDITOR=/usr/bin/editor
+ENV PGDATA=$PGDATA PATH=$PATH:$PGBIN
+
+COPY patroni /patroni/
+COPY extras/confd/conf.d/haproxy.toml /etc/confd/conf.d/
+COPY extras/confd/templates/haproxy.tmpl /etc/confd/templates/
+COPY patroni*.py docker/entrypoint.sh /
+COPY postgres?.yml $PGHOME/
+
+WORKDIR $PGHOME
+
+RUN sed -i 's/env python/&3/' /patroni*.py \
+    # "fix" patroni configs
+    && sed -i 's/^\(  connect_address:\|  - host\)/#&/' postgres?.yml \
+    && sed -i 's/^  listen: 127.0.0.1/  listen: 0.0.0.0/' postgres?.yml \
+    && sed -i "s|^\(  data_dir: \).*|\1$PGDATA|" postgres?.yml \
+    && sed -i "s|^#\(  bin_dir: \).*|\1$PGBIN|" postgres?.yml \
+    && sed -i 's/^  - encoding: UTF8/  - locale: en_US.UTF-8\n&/' postgres?.yml \
+    && sed -i 's/^\(scope\|name\|etcd\|  host\|  authentication\|  pg_hba\|  parameters\):/#&/' postgres?.yml \
+    && sed -i 's/^    \(replication\|superuser\|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 \
+    && chown -R postgres:postgres $PGHOME /run /etc/haproxy
 
-ENV LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8
-ENTRYPOINT ["/bin/bash", "/entrypoint.sh"]
 USER postgres
+
+ENTRYPOINT ["/bin/sh", "/entrypoint.sh"]

docker-compose.yml

@@ -1,58 +1,69 @@
 # docker compose file for running a 3-node PostgreSQL cluster
-# with etcd as the SIS
+# with 3-node etcd cluster as the DCS and one haproxy node
+version: "2"
 
-patroni_etcd:
-    container_name: patroni_etcd
-    image: patroni
-    command: --etcd
+networks:
+    demo:
 
-dbnode1:
-    image: patroni
-    hostname: dbnode1
-    links:
-        - patroni_etcd:patroni_etcd
-    volumes:
-        - ./patroni:/patroni
-    env_file: docker/patroni-secrets.env
-    environment:
-        PATRONI_ETCD_URL: http://patroni_etcd:2379
-        PATRONI_NAME: dbnode1
-        PATRONI_SCOPE: testcluster
+services:
+    etcd1:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/etcd.env
+        container_name: demo-etcd1
+        hostname: etcd1
+        command: etcd -name etcd1 -initial-advertise-peer-urls http://etcd1:2380
 
-dbnode2:
-    image: patroni
-    hostname: dbnode2
-    links:
-        - patroni_etcd:patroni_etcd
-    volumes:
-        - ./patroni:/patroni
-    env_file: docker/patroni-secrets.env
-    environment:
-        PATRONI_ETCD_URL: http://patroni_etcd:2379
-        PATRONI_NAME: dbnode2
-        PATRONI_SCOPE: testcluster
+    etcd2:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/etcd.env
+        container_name: demo-etcd2
+        hostname: etcd2
+        command: etcd -name etcd2 -initial-advertise-peer-urls http://etcd2:2380
 
-dbnode3:
-    image: patroni
-    hostname: dbnode3
-    links:
-        - patroni_etcd:patroni_etcd
-    volumes:
-        - ./patroni:/patroni
-    env_file: docker/patroni-secrets.env
-    environment:
-        PATRONI_ETCD_URL: http://patroni_etcd:2379
-        PATRONI_NAME: dbnode3
-        PATRONI_SCOPE: testcluster
+    etcd3:
+        image: patroni
+        networks: [ demo ]
+        env_file: docker/etcd.env
+        container_name: demo-etcd3
+        hostname: etcd3
+        command: etcd -name etcd3 -initial-advertise-peer-urls http://etcd3:2380
 
-haproxy:
-    image: patroni
-    links:
-        - patroni_etcd:patroni_etcd
-    ports:
-        - "5000:5000"
-        - "5001:5001"
-    environment:
-        PATRONI_ETCD_URL: http://patroni_etcd:2379
-        PATRONI_SCOPE: testcluster
-    command: --confd
+    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 ]
+        env_file: docker/patroni.env
+        hostname: haproxy
+        container_name: demo-haproxy
+        ports:
+            - "5000:5000"
+            - "5001:5001"
+        command: haproxy

docker/README.md

@@ -1,47 +1,117 @@
 # Patroni Dockerfile
-You can run Patroni in a docker container using this Dockerfile, or by using one of the Docker image at
-
-    https://registry.opensource.zalan.do/v1/repositories/acid/patroni/tags
+You can run Patroni in a docker container using this Dockerfile
 
 This Dockerfile is meant in aiding development of Patroni and quick testing of features. It is not a production-worthy
 Dockerfile
 
+    docker build -t patroni .
+
 # Examples
 
 ## Standalone Patroni
 
-    docker run -d registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT
+    docker run -d patroni
 
-## Multiple Patroni's communicating with a standalone etcd inside Docker
-
-Basically what you would do would be: 
-
-* Run 1 container which provides etcd
-
-        docker run -d <IMAGE> --etcd-only
-
-* Run n containers running Patroni, passing the `--etcd` option to the `docker run` command
-
-        docker run -d <IMAGE> --etcd=<IP FROM etcd CONTAINER:PORT>
-
-To automate this you can run the following script:
-
-    dev_patroni_cluster.sh [OPTIONS]
-
-    Options:
-
-        --image     IMAGE    The Docker image to use for the cluster
-        --members   INT      The number of members for the cluster
-        --name      NAME     The name of the new cluster
+## Three-node Patroni cluster with three-node etcd cluster and one haproxy container using docker-compose
 
 Example session:
 
-    $ ./dev_patroni_cluster.sh --image registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT --members=2 --name=bravo
-    The etcd container is 6be871a11cb373406ca5ea1c6b39e1.0-SNAPSHOTfdde9fb1d6177212d6ad0c0d1bd9b563, ip=172.17.1.24
-    Started Patroni container 67e611f2eca7c40f9e6e0e24a4a8f2cba7e3e56d22a420e15ab9240a37a9d7a4, ip=172.17.1.25
-    Started Patroni container 47dd12ae635ab83b039f5889e250048b606ed5e48e3650b69e365e7e1d4acbcf, ip=172.17.1.26
+    $ docker-compose up -d
+    Creating demo-haproxy ...
+    Creating demo-patroni2 ...
+    Creating demo-patroni1 ...
+    Creating demo-patroni3 ...
+    Creating demo-etcd2 ...
+    Creating demo-etcd1 ...
+    Creating demo-etcd3 ...
+    Creating demo-haproxy
+    Creating demo-patroni2
+    Creating demo-patroni1
+    Creating demo-patroni3
+    Creating demo-etcd1
+    Creating demo-etcd2
+    Creating demo-etcd2 ... done
+
     $ docker ps
-    CONTAINER ID        IMAGE                                         COMMAND                CREATED             STATUS              PORTS                          NAMES
-    47dd12ae635a        registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT   "/bin/bash /entrypoi   10 seconds ago      Up 8 seconds        4001/tcp, 5432/tcp, 2380/tcp   bravo_OR64g8bx
-    67e611f2eca7        registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT   "/bin/bash /entrypoi   11 seconds ago      Up 10 seconds       2380/tcp, 4001/tcp, 5432/tcp   bravo_si9no8iz
-    6be871a11cb3        registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT   "/bin/bash /entrypoi   12 seconds ago      Up 10 seconds       4001/tcp, 5432/tcp, 2380/tcp   bravo_etcd
+    CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                              NAMES
+    5b7a90b4cfbf        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 27 seconds                                          demo-etcd2
+    e30eea5222f2        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 27 seconds                                          demo-etcd1
+    83bcf3cb208f        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 27 seconds                                          demo-etcd3
+    922532c56e7d        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 28 seconds                                          demo-patroni3
+    14f875e445f3        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 28 seconds                                          demo-patroni2
+    110d1073b383        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 28 seconds                                          demo-patroni1
+    5af5e6e36028        patroni             "/bin/sh /entrypoint…"   29 seconds ago      Up 28 seconds       0.0.0.0:5000-5001->5000-5001/tcp   demo-haproxy
+
+    $ docker logs demo-patroni1
+    2019-02-20 08:19:32,714 INFO: Failed to import patroni.dcs.consul
+    2019-02-20 08:19:32,737 INFO: Selected new etcd server http://etcd3:2379
+    2019-02-20 08:19:35,140 INFO: Lock owner: None; I am patroni1
+    2019-02-20 08:19:35,174 INFO: trying to bootstrap a new cluster
+    ...
+    2019-02-20 08:19:39,310 INFO: postmaster pid=37
+    2019-02-20 08:19:39.314 UTC [37] LOG:  listening on IPv4 address "0.0.0.0", port 5432
+    2019-02-20 08:19:39.321 UTC [37] LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5432"
+    2019-02-20 08:19:39.353 UTC [39] LOG:  database system was shut down at 2019-02-20 08:19:36 UTC
+    2019-02-20 08:19:39.354 UTC [40] FATAL:  the database system is starting up
+    localhost:5432 - rejecting connections
+    2019-02-20 08:19:39.369 UTC [37] LOG:  database system is ready to accept connections
+    localhost:5432 - accepting connections
+    2019-02-20 08:19:39,383 INFO: establishing a new patroni connection to the postgres cluster
+    2019-02-20 08:19:39,408 INFO: running post_bootstrap
+    2019-02-20 08:19:39,432 WARNING: Could not activate Linux watchdog device: "Can't open watchdog device: [Errno 2] No such file or directory: '/dev/watchdog'"
+    2019-02-20 08:19:39,515 INFO: initialized a new cluster
+    2019-02-20 08:19:49,424 INFO: Lock owner: patroni1; I am patroni1
+    2019-02-20 08:19:49,447 INFO: Lock owner: patroni1; I am patroni1
+    2019-02-20 08:19:49,480 INFO: no action.  i am the leader with the lock
+    2019-02-20 08:19:59,422 INFO: Lock owner: patroni1; I am patroni1
+
+    $ docker exec -ti demo-patroni1 bash
+    postgres@patroni1:~$ patronictl list
+    +-------------+----------+------------+--------+---------+----+-----------+
+    |   Cluster   |  Member  |    Host    |  Role  |  State  | TL | Lag in MB |
+    +-------------+----------+------------+--------+---------+----+-----------+
+    | testcluster | patroni1 | 172.21.0.3 | Leader | running |  1 |         0 |
+    | testcluster | patroni2 | 172.21.0.4 |        | running |  1 |         0 |
+    | testcluster | patroni3 | 172.21.0.5 |        | running |  1 |         0 |
+    +-------------+----------+------------+--------+---------+----+-----------+
+
+    postgres@patroni1:~$ etcdctl ls --recursive --sort -p /service/testcluster
+    /service/testcluster/config
+    /service/testcluster/initialize
+    /service/testcluster/leader
+    /service/testcluster/members/
+    /service/testcluster/members/patroni1
+    /service/testcluster/members/patroni2
+    /service/testcluster/members/patroni3
+    /service/testcluster/optime/
+    /service/testcluster/optime/leader
+
+    postgres@patroni1:~$ etcdctl member list
+    1bab629f01fa9065: name=etcd3 peerURLs=http://etcd3:2380 clientURLs=http://etcd3:2379 isLeader=false
+    8ecb6af518d241cc: name=etcd2 peerURLs=http://etcd2:2380 clientURLs=http://etcd2:2379 isLeader=true
+    b2e169fcb8a34028: name=etcd1 peerURLs=http://etcd1:2380 clientURLs=http://etcd1:2379 isLeader=false
+    postgres@patroni1:~$ exit
+
+    $ psql -h localhost -p 5000 -U postgres -W
+    Password: postgres
+    psql (11.2 (Ubuntu 11.2-1.pgdg18.04+1), server 10.7 (Debian 10.7-1.pgdg90+1))
+    Type "help" for help.
+
+    localhost/postgres=# select pg_is_in_recovery();
+     pg_is_in_recovery
+    ───────────────────
+     f
+    (1 row)
+
+    localhost/postgres=# \q
+
+    $ psql -h localhost -p 5001 -U postgres -W
+    Password: postgres
+    psql (11.2 (Ubuntu 11.2-1.pgdg18.04+1), server 10.7 (Debian 10.7-1.pgdg90+1))
+    Type "help" for help.
+
+    localhost/postgres=# select pg_is_in_recovery();
+     pg_is_in_recovery
+    ───────────────────
+     t
+    (1 row)

docker/dev_patroni_cluster.sh

@@ -1,104 +0,0 @@
-#!/bin/bash
-
-DOCKER_IMAGE="registry.opensource.zalan.do/acid/patroni:1.0-SNAPSHOT"
-MEMBERS=3
-
-
-function usage()
-{
-    cat <<__EOF__
-Usage: $0 
-
-Options:
-
-    --image     IMAGE    The Docker image to use for the cluster
-    --members   INT      The number of members for the cluster
-    --name      NAME     The name of the new cluster
-
-Examples:
-
-    $0 --image ${DOCKER_IMAGE}
-    $0
-    $0 --image ${DOCKER_IMAGE} --members=2
-__EOF__
-}
-
-
-optspec=":-:"
-while getopts "$optspec" optchar; do
-    case "${optchar}" in
-        -)
-            case "${OPTARG}" in
-                help)
-                    usage
-                    exit 0
-                    ;;
-                name)
-                    PATRONI_SCOPE="${!OPTIND}"; OPTIND=$(( $OPTIND + 1 ))
-                    ;;
-                name=*)
-                    PATRONI_SCOPE="${OPTARG#*=}"
-                    ;;
-                image)
-                    DOCKER_IMAGE="${!OPTIND}"; OPTIND=$(( $OPTIND + 1 ))
-                    ;;
-                image=*)
-                    DOCKER_IMAGE="${OPTARG#*=}"
-                    ;;
-                members)
-                    MEMBERS="${!OPTIND}"; OPTIND=$(( $OPTIND + 1 ))
-                    ;;
-                members=*)
-                    MEMBERS="${OPTARG#*=}"
-                    ;;
-                *)
-                    if [ "$OPTERR" = 1 ] && [ "${optspec:0:1}" != ":" ]; then
-                        echo "Unknown option --${OPTARG}" >&2
-                    fi
-                    ;;
-            esac;;
-        *)
-            if [ "$OPTERR" != 1 ] || [ "${optspec:0:1}" = ":" ]; then
-                echo "Non-option argument: '-${OPTARG}'" >&2
-                usage
-                exit 1
-            fi
-            ;;
-    esac
-done
-
-if [ -z ${PATRONI_SCOPE} ]; then
-    PATRONI_SCOPE=$(cat /dev/urandom | LC_ALL=C tr -dc 'a-z0-9' | head -c 8)
-fi
-
-function docker_run()
-{
-    local name=$1
-    shift
-    container=$(docker run -d --name=$name $*)
-    container_ip=$(docker inspect --format '{{ .NetworkSettings.IPAddress }}' ${container})
-    echo "Started container ${name}, ip=${container_ip}"
-}
-
-
-ETCD_CONTAINER="${PATRONI_SCOPE}_etcd"
-docker_run ${ETCD_CONTAINER} ${DOCKER_IMAGE} --etcd
-
-DOCKER_ARGS="--link=${ETCD_CONTAINER}:${ETCD_CONTAINER} -e PATRONI_SCOPE=${PATRONI_SCOPE} -e PATRONI_ETCD_URL=http://${ETCD_CONTAINER}:2379"
-PATRONI_ENV=$(sed 's/#.*//g' docker/patroni-secrets.env | sed -n 's/^PATRONI_.*$/-e &/p' | tr '\n' ' ')
-PATRONI_VOLUME="-v $(dirname $(dirname $(realpath $0)))/patroni:/patroni"
-
-for i in $(seq 1 "${MEMBERS}"); do
-    container_name=postgres${i}
-    docker_run "${PATRONI_SCOPE}_${container_name}" \
-        $PATRONI_VOLUME \
-        $DOCKER_ARGS \
-        $PATRONI_ENV \
-        -e PATRONI_NAME=${container_name} \
-        ${DOCKER_IMAGE}
-done
-
-docker_run "${PATRONI_SCOPE}_haproxy" \
-    -p=5000 -p=5001 \
-    $DOCKER_ARGS \
-    ${DOCKER_IMAGE} --confd

docker/entrypoint.sh

@@ -1,115 +1,60 @@
-#!/bin/bash
+#!/bin/sh
 
-function usage()
-{
-    cat <<__EOF__
-Usage: $0
+if [ -f /a.tar.xz ]; then
+    echo "decompressing image..."
+    sudo tar xpJf /a.tar.xz -C / > /dev/null 2>&1
+    sudo rm /a.tar.xz
+    sudo ln -snf dash /bin/sh
+fi
 
-Options:
+readonly PATRONI_SCOPE=${PATRONI_SCOPE:-batman}
+PATRONI_NAMESPACE=${PATRONI_NAMESPACE:-/service}
+readonly PATRONI_NAMESPACE=${PATRONI_NAMESPACE%/}
+readonly DOCKER_IP=$(hostname --ip-address)
 
-    --etcd      Do not run Patroni, run a standalone etcd
-    --confd     Do not run Patroni, run a standalone confd
-    --zookeeper Do not run Patroni, run a standalone zookeeper
-
-Examples:
-
-    $0 --etcd
-    $0 --confd
-    $0 --zookeeper
-    $0
-__EOF__
-}
-
-DOCKER_IP=$(hostname --ip-address)
-PATRONI_SCOPE=${PATRONI_SCOPE:-batman}
-ETCD_ARGS="--data-dir /tmp/etcd.data -advertise-client-urls=http://${DOCKER_IP}:2379 -listen-client-urls=http://0.0.0.0:2379"
-
-optspec=":vh-:"
-while getopts "$optspec" optchar; do
-    case "${optchar}" in
-        -)
-            case "${OPTARG}" in
-                confd)
-                    haproxy -f /etc/haproxy/haproxy.cfg -p /var/run/haproxy.pid -D
-                    CONFD="confd -prefix=${PATRONI_NAMESPACE:-/service}/$PATRONI_SCOPE -interval=10 -backend"
-                    if [ ! -z ${PATRONI_ZOOKEEPER_HOSTS} ]; then
-                        while ! /usr/share/zookeeper/bin/zkCli.sh -server ${PATRONI_ZOOKEEPER_HOSTS} ls /; do
-                            sleep 1
-                        done
-                        exec $CONFD zookeeper -node ${PATRONI_ZOOKEEPER_HOSTS}
-                    else
-                        while ! curl -s ${PATRONI_ETCD_URL}/v2/members | jq -r '.members[0].clientURLs[0]' | grep -q http; do
-                            sleep 1
-                        done
-                        exec $CONFD etcd -node $PATRONI_ETCD_URL
-                    fi
-                    ;;
-                etcd)
-                    exec etcd $ETCD_ARGS
-                    ;;
-                zookeeper)
-                    exec /usr/share/zookeeper/bin/zkServer.sh start-foreground
-                    ;;
-                cheat)
-                    CHEAT=1
-                    ;;
-                help)
-                    usage
-                    exit 0
-                    ;;
-                *)
-                    if [ "$OPTERR" = 1 ] && [ "${optspec:0:1}" != ":" ]; then
-                        echo "Unknown option --${OPTARG}" >&2
-                    fi
-                    ;;
-            esac;;
-        *)
-            if [ "$OPTERR" != 1 ] || [ "${optspec:0:1}" = ":" ]; then
-                echo "Non-option argument: '-${OPTARG}'" >&2
-                usage
-                exit 1
-            fi
-            ;;
-    esac
-done
+case "$1" in
+    haproxy)
+        haproxy -f /etc/haproxy/haproxy.cfg -p /var/run/haproxy.pid -D
+        CONFD="confd -prefix=$PATRONI_NAMESPACE/$PATRONI_SCOPE -interval=10 -backend"
+        if [ ! -z "$PATRONI_ZOOKEEPER_HOSTS" ]; then
+            while ! /usr/share/zookeeper/bin/zkCli.sh -server $PATRONI_ZOOKEEPER_HOSTS ls /; do
+                sleep 1
+            done
+            exec dumb-init $CONFD zookeeper -node $PATRONI_ZOOKEEPER_HOSTS
+        else
+            while ! etcdctl cluster-health 2> /dev/null; do
+                sleep 1
+            done
+            exec dumb-init $CONFD etcd -node $(echo $ETCDCTL_ENDPOINTS | sed 's/,/ -node /g')
+        fi
+        ;;
+    etcd)
+        exec "$@" -advertise-client-urls http://$DOCKER_IP:2379
+        ;;
+    zookeeper)
+        exec /usr/share/zookeeper/bin/zkServer.sh start-foreground
+        ;;
+esac
 
 ## We start an etcd
-if [[ -z ${PATRONI_ETCD_URL} && -z ${PATRONI_ZOOKEEPER_HOSTS} ]]; then
-    etcd $ETCD_ARGS > /var/log/etcd.log 2> /var/log/etcd.err &
+if [ -z "$PATRONI_ETCD_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
 
 export PATRONI_SCOPE
-export PATRONI_NAME="${PATRONI_NAME:-${HOSTNAME}}"
-export PATRONI_RESTAPI_CONNECT_ADDRESS="${DOCKER_IP}:8008"
+export PATRONI_NAMESPACE
+export PATRONI_NAME="${PATRONI_NAME:-$(hostname)}"
+export PATRONI_RESTAPI_CONNECT_ADDRESS="$DOCKER_IP:8008"
 export PATRONI_RESTAPI_LISTEN="0.0.0.0:8008"
-export PATRONI_admin_PASSWORD="${PATRONI_admin_PASSWORD:=admin}"
+export PATRONI_admin_PASSWORD="${PATRONI_admin_PASSWORD:-admin}"
 export PATRONI_admin_OPTIONS="${PATRONI_admin_OPTIONS:-createdb, createrole}"
-export PATRONI_POSTGRESQL_CONNECT_ADDRESS="${DOCKER_IP}:5432"
+export PATRONI_POSTGRESQL_CONNECT_ADDRESS="$DOCKER_IP:5432"
 export PATRONI_POSTGRESQL_LISTEN="0.0.0.0:5432"
-export PATRONI_POSTGRESQL_DATA_DIR="data/${PATRONI_SCOPE}"
+export PATRONI_POSTGRESQL_DATA_DIR="${PATRONI_POSTGRESQL_DATA_DIR:-$PGDATA}"
 export PATRONI_REPLICATION_USERNAME="${PATRONI_REPLICATION_USERNAME:-replicator}"
-export PATRONI_REPLICATION_PASSWORD="${PATRONI_REPLICATION_PASSWORD:-abcd}"
+export PATRONI_REPLICATION_PASSWORD="${PATRONI_REPLICATION_PASSWORD:-replicate}"
 export PATRONI_SUPERUSER_USERNAME="${PATRONI_SUPERUSER_USERNAME:-postgres}"
 export PATRONI_SUPERUSER_PASSWORD="${PATRONI_SUPERUSER_PASSWORD:-postgres}"
-export PATRONI_POSTGRESQL_PGPASS="$HOME/.pgpass"
 
-cat > /patroni.yml <<__EOF__
-bootstrap:
-  dcs:
-    postgresql:
-      use_pg_rewind: true
-
-  pg_hba:
-  - host all all 0.0.0.0/0 md5
-  - host replication replicator ${DOCKER_IP}/16    md5
-__EOF__
-
-mkdir -p "$HOME/.config/patroni"
-[ -h "$HOME/.config/patroni/patronictl.yaml" ] || ln -s /patroni.yml "$HOME/.config/patroni/patronictl.yaml"
-
-[ -z $CHEAT ] && exec python3 /patroni.py /patroni.yml
-
-while true; do
-    sleep 60
-done
+exec python3 /patroni.py postgres0.yml

docker/etcd.env

@@ -0,0 +1,5 @@
+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

@@ -1,3 +1,6 @@
+PATRONI_SCOPE=demo
+PATRONI_ETCD_HOSTS='etcd1:2379','etcd2:2379','etcd3:2379'
+
 PATRONI_RESTAPI_USERNAME=admin
 PATRONI_RESTAPI_PASSWORD=admin
 PATRONI_SUPERUSER_USERNAME=postgres
@@ -6,3 +9,6 @@ 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

@@ -11,8 +11,13 @@ 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
--  **PATRONI\_LOGLEVEL**: sets the general logging level (see `the docs for Python logging <https://docs.python.org/3.6/library/logging.html#levels>`_)
--  **PATRONI\_REQUESTS_LOGLEVEL**: sets the logging level for all HTTP requests e.g. Kubernetes API calls (see `the docs for Python logging <https://docs.python.org/3.6/library/logging.html#levels>`_)
+-  **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\_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\_DIR**: Directory to write application logs to. The directory must exist and be writable by the user executing Patroni. If you set this env variable, the application will retain 4 25MB logs by default. You can tune those retention values with `PATRONI_LOG_FILE_NUM` and `PATRONI_LOG_FILE_SIZE` (see below).
+-  **PATRONI\_LOG\_FILE\_NUM**: The number of application logs to retain.
+-  **PATRONI\_LOG\_FILE\_SIZE**: Size of patroni.log file (in bytes) that triggers a log rolling.
+-  **PATRONI\_LOG\_LOGGERS**: Redefine logging level per python module. Example ``PATRONI_LOG_LOGGERS="{patroni.postmaster: WARNING, urllib3: DEBUG}"``
 
 Bootstrap configuration
 -----------------------
@@ -36,16 +41,23 @@ 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\_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\_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
 
 Etcd
 ----
--  **PATRONI\_ETCD\_HOST**: the host:port for the etcd endpoint.
--  **PATRONI\_ETCD\_HOSTS**: list of etcd endpoints in format host1:port1,host2:port2,etc...
--  **PATRONI\_ETCD\_URL**: url for the etcd, in format: http(s)://(username:password@)host:port
+
 -  **PATRONI\_ETCD\_PROXY**: proxy url for the etcd. If you are connecting to the etcd using proxy, use this parameter instead of **PATRONI\_ETCD\_URL**
+-  **PATRONI\_ETCD\_URL**: url for the etcd, in format: http(s)://(username:password@)host:port
+-  **PATRONI\_ETCD\_HOSTS**: list of etcd endpoints in format 'host1:port1','host2:port2',etc...
+-  **PATRONI\_ETCD\_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 but stick to a fixed list of **hosts**.
+-  **PATRONI\_ETCD\_PROTOCOL**: http or https, if not specified http is used. If the **url** or **proxy** is specified - will take protocol from them.
+-  **PATRONI\_ETCD\_HOST**: the host:port for the etcd endpoint.
 -  **PATRONI\_ETCD\_SRV**: Domain to search the SRV record(s) for cluster autodiscovery.
+-  **PATRONI\_ETCD\_USERNAME**: username for etcd authentication.
+-  **PATRONI\_ETCD\_PASSWORD**: password for etcd authentication.
 -  **PATRONI\_ETCD\_CACERT**: The ca certificate. If present it will enable validation.
--  **PATRONI\_ETCD\_CERT**: File with the client certificate
+-  **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.
 
 Exhibitor
@@ -79,7 +91,7 @@ PostgreSQL
 -  **PATRONI\_SUPERUSER\_PASSWORD**: password for the superuser, set during initialization (initdb).
 
 REST API
--------- 
+--------
 -  **PATRONI\_RESTAPI\_CONNECT\_ADDRESS**: IP address and port to access the REST API.
 -  **PATRONI\_RESTAPI\_LISTEN**: IP address and port that Patroni will listen to, to provide health-check information for HAProxy.
 -  **PATRONI\_RESTAPI\_USERNAME**: Basic-auth username to protect unsafe REST API endpoints.

docs/README.rst

@@ -66,6 +66,8 @@ Note that external tools to call in the replica creation or custom bootstrap scr
 independently of Patroni.
 
 
+.. _running_configuring:
+
 Running and Configuring
 -----------------------
 

docs/SETTINGS.rst

@@ -10,6 +10,20 @@ Global/Universal
 -  **namespace**: path within the configuration store where Patroni will keep information about the cluster. Default value: "/service"
 -  **scope**: cluster name
 
+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>`_)
+-  **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>`_)
+-  **dir**: Directory to write application logs to. The directory must exist and be writable by the user executing Patroni. If you set this value, the application will retain 4 25MB logs by default. You can tune those retention values with `file_num` and `file_size` (see below).
+-  **file\_num**: The number of application logs to retain.
+-  **file\_size**: Size of patroni.log file (in bytes) that triggers a log rolling.
+-  **loggers**: This section allows redefining logging level per python module
+    -  **patroni.postmaster: WARNING**
+    -  **urllib3: DEBUG**
+
+.. _bootstrap_settings:
+
 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.
@@ -23,8 +37,21 @@ Bootstrap configuration
     -  **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. 
+        -  **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``
@@ -61,6 +88,8 @@ Most of the parameters are optional, but you have to specify one of the **host**
 -  **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.
 -  **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
+-  **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
 
 Etcd
 ----
@@ -68,14 +97,15 @@ 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
 -  **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
+-  **username**: (optional) username for etcd authentication.
 -  **password**: (optional) password for etcd authentication.
 -  **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**.
 
 Exhibitor
@@ -109,15 +139,15 @@ PostgreSQL
         -  **password**: replication password; the user will be created during initialization.
 -  **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 cluster restarts.
-        -  **on\_role\_change**: run this script when the cluster is being promoted or demoted.
-        -  **on\_start**: run this script when the cluster starts.
-        -  **on\_stop**: run this script when the cluster stops.
+        -  **on\_restart**: run this script when the postgres restarts (without changing role).
+        -  **on\_role\_change**: run this script when the postgres is being promoted or demoted.
+        -  **on\_start**: run this script when the postgres starts.
+        -  **on\_stop**: run this script when the postgres stops.
 -  **connect\_address**: IP address + port through which Postgres is accessible from other nodes and applications.
 -  **create\_replica\_methods**: an ordered list of the create methods for turning a Patroni node into a new replica.
    "basebackup" is the default method; other methods are assumed to refer to scripts, each of which is configured as its
    own config item. See :ref:`custom replica creation methods documentation <custom_replica_creation>` for further explanation.
--  **data\_dir**: The location of the Postgres data directory, either existing or to be initialized by Patroni.
+-  **data\_dir**: The location of the Postgres data directory, either :ref:`existing <existing_data>` or to be initialized by Patroni.
 -  **config\_dir**: The location of the Postgres configuration directory, defaults to the data directory. Must be writable by Patroni.
 -  **bin\_dir**: Path to PostgreSQL binaries (pg_ctl, pg_rewind, pg_basebackup, postgres). The default value is an empty string meaning that PATH environment variable will be used to find the executables.
 -  **listen**: IP address + port that Postgres listens to; must be accessible from other nodes in the cluster, if you're using streaming replication. Multiple comma-separated addresses are permitted, as long as the port component is appended after to the last one with a colon, i.e. ``listen: 127.0.0.1,127.0.0.2:5432``. Patroni will use the first address from this list to establish local connections to the PostgreSQL node.
@@ -132,12 +162,15 @@ PostgreSQL
 -  **pg\_ctl\_timeout**: How long should pg_ctl wait when doing ``start``, ``stop`` or ``restart``. Default value is 60 seconds.
 -  **use\_pg\_rewind**: try to use pg\_rewind on the former leader when it joins cluster as a replica.
 -  **remove\_data\_directory\_on\_rewind\_failure**: If this option is enabled, Patroni will remove postgres data directory and recreate replica. Otherwise it will try to follow the new leader. Default value is **false**.
+-  **remove\_data\_directory\_on\_diverged\_timelines**: Patroni will remove postgres data directory and recreate 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".
 
 REST API
--------- 
--  **connect\_address**: IP address (or hostname) and port, to access the Patroni's REST API. 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.
--  **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)  
+--------
+-  **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.
+
+-  **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**:
             -  **username**: Basic-auth username to protect unsafe REST API endpoints.
@@ -146,6 +179,15 @@ REST API
         -  **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.
         -  **keyfile**: Specifies the file with the secret key in the PEM format.
 
+.. _patronictl_settings:
+
+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.
+    -  **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.
+
 ZooKeeper
 ----------
 -  **hosts**: list of ZooKeeper cluster members in format: ['host1:port1', 'host2:port2', 'etc...'].

docs/dynamic_configuration.rst

@@ -76,6 +76,7 @@ Also, the following Patroni configuration options can be changed only dynamicall
 - loop_wait: 10
 - retry_timeouts: 10
 - maximum_lag_on_failover: 1048576
+- check_timeline: false
 - postgresql.use_slots: true
 
 Upon changing these options, Patroni will read the relevant section of the configuration stored in DCS and change its

docs/existing_data.rst

@@ -0,0 +1,35 @@
+.. _existing_data:
+
+Convert a Standalone to a Patroni Cluster
+=========================================
+
+This section describes the process for converting a standalone PostgreSQL instance into a Patroni cluster.
+
+To deploy a Patroni cluster without using a pre-existing PostgreSQL instance, see :ref:`Running and Configuring <running_configuring>` instead.
+
+Procedure
+---------
+
+A Patroni cluster can be started with a data directory from a single-node PostgreSQL database. This is achieved by following closely these steps:
+
+#. Manually start PostgreSQL daemon
+#. Create Patroni superuser and replication users as defined in the :ref:`authentication <postgresql_settings>` section of the Patroni configuration. If this user is created in SQL, the following queries achieve this:
+
+.. code-block:: sql
+  CREATE USER $PATRONI_SUPERUSER_USERNAME WITH SUPERUSER ENCRYPTED PASSWORD '$PATRONI_SUPERUSER_PASSWORD';
+  CREATE USER $PATRONI_REPLICATION_USERNAME WITH REPLICATION ENCRYPTED PASSWORD '$PATRONI_REPLICATION_PASSWORD';
+
+#. 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.
+#. Ask Patroni to restart the node with ``patronictl restart cluster-name node-name``.
+
+
+FAQ
+---
+
+#. During Patroni startup, Patroni complains that it cannot bind to the PostgreSQL port.
+
+You need to verify ``listen_addresses`` and ``port`` in ``postgresql.conf`` and ``postgresql.listen`` in ``patroni.yml``. Don't forget that ``pg_hba.conf`` should allow such access.
+
+#. After asking Patroni to restart the node, PostgreSQL displays the error message ``could not open configuration file "/etc/postgresql/10/main/pg_hba.conf": No such file or directory``
+
+It can mean various things depending on how you manage PostgreSQL configuration. If you specified `postgresql.config_dir`, Patroni generates the ``pg_hba.conf`` based on the settings in the :ref:`bootstrap <bootstrap_settings>` section only when it bootstraps a new cluster. In this scenario the ``PGDATA`` was not empty, therefore no bootstrap happened. This file must exist beforehand.

docs/releases.rst

@@ -3,6 +3,266 @@
 Release notes
 =============
 
+Version 1.5.6
+-------------
+
+**New features**
+
+- Support work with etcd cluster via set of proxies (Alexander Kukushkin)
+
+  It might happen that etcd cluster is not accessible directly but via set of proxies. In this case Patroni will not perform etcd topology discovery but just round-robin via proxy hosts. Behavior is controlled by `etcd.use_proxies`.
+
+- Changed callbacks behavior when role on the node is changed (Alexander)
+
+  If the role was changed from `master` or `standby_leader` to `replica` or from `replica` to `standby_leader`, `on_restart` callback will not be called anymore in favor of `on_role_change` callback.
+
+- Change the way how we start postgres (Alexander)
+
+  Use `multiprocessing.Process` instead of executing itself and `multiprocessing.Pipe` to transmit the postmaster pid to the Patroni process. Before that we were using pipes, what was leaving postmaster process with stdin closed.
+
+**Bug fixes**
+
+- Fix role returned by REST API for the standby leader (Alexander)
+
+  It was incorrectly returning `replica` instead of `standby_leader`
+
+- Wait for callback end if it could not be killed (Julien Tachoires)
+
+  Patroni doesn't have enough privileges to terminate the callback script running under `sudo` what was cancelling the new callback. If the running script could not be killed, Patroni will wait until it finishes and then run the next callback.
+
+- Reduce lock time taken by dcs.get_cluster method (Alexander)
+
+  Due to the lock being held DCS slowness was affecting the REST API health checks causing false positives.
+
+- Improve cleaning of PGDATA when `pg_wal`/`pg_xlog` is a symlink (Julien)
+
+  In this case Patroni will explicitly remove files from the target directory.
+
+- Remove unnecessary usage of os.path.relpath (Ants Aasma)
+
+  It depends on being able to resolve the working directory, what will fail if Patroni is started in a directory that is later unlinked from the filesystem.
+
+- Do not enforce ssl version when communicating with Etcd (Alexander)
+
+  For some unknown reason python3-etcd on debian and ubuntu are not based on the latest version of the package and therefore it enforces TLSv1 which is not supported by Etcd v3. We solved this problem on Patroni side.
+
+Version 1.5.5
+-------------
+
+This version introduces the possibility of automatic reinit of the former master, improves patronictl list output and fixes a number of bugs.
+
+**New features**
+
+- Add support of `PATRONI_ETCD_PROTOCOL`, `PATRONI_ETCD_USERNAME` and `PATRONI_ETCD_PASSWORD` environment variables (Étienne M)
+
+  Before it was possible to configure them only in the config file or as a part of `PATRONI_ETCD_URL`, which is not always convenient.
+
+- Make it possible to automatically reinit the former master (Alexander Kukushkin)
+
+  If the pg_rewind is disabled or can't be used, the former master could fail to start as a new replica due to diverged timelines. In this case, the only way to fix it is wiping the data directory and reinitializing. This behavior could be changed by setting `postgresql.remove_data_directory_on_diverged_timelines`. When it is set, Patroni will wipe the data directory and reinitialize the former master automatically.
+
+- Show information about timelines in patronictl list (Alexander)
+
+  It helps to detect stale replicas. In addition to that, `Host` will include ':{port}' if the port value isn't default or there is more than one member running on the same host.
+
+- Create a headless service associated with the $SCOPE-config endpoint (Alexander)
+
+  The "config" endpoint keeps information about the cluster-wide Patroni and Postgres configuration, history file, and last but the most important, it holds the `initialize` key. When the Kubernetes master node is restarted or upgraded, it removes endpoints without services. The headless service will prevent it from being removed.
+
+**Bug fixes**
+
+- Adjust the read timeout for the leader watch blocking query (Alexander)
+
+  According to the Consul documentation, the actual response timeout is increased by a small random amount of additional wait time added to the supplied maximum wait time to spread out the wake up time of any concurrent requests. It adds up to `wait / 16` additional time to the maximum duration. In our case we are adding `wait / 15` or 1 second depending on what is bigger.
+
+- Always use replication=1 when connecting via replication protocol to the postgres (Alexander)
+
+  Starting from Postgres 10 the line in the pg_hba.conf with database=replication doesn't accept connections with the parameter replication=database.
+
+- Don't write primary_conninfo into recovery.conf for wal-only standby cluster (Alexander)
+
+  Despite not having neither `host` nor `port` defined in the `standby_cluster` config, Patroni was putting the `primary_conninfo` into the `recovery.conf`, which is useless and generating a lot of errors.
+
+
+Version 1.5.4
+-------------
+
+This version implements flexible logging and fixes a number of bugs.
+
+**New features**
+
+- Improvements in logging infrastructure (Alexander Kukushkin, Lucas Capistrant, Alexander Anikin)
+
+  Logging configuration could be configured not only from environment variables but also from Patroni config file. It makes it possible to change logging configuration in runtime by updating config and doing reload or sending SIGHUP to the Patroni process. By default Patroni writes logs to stderr, but now it becomes possible to write logs directly into the file and rotate when it reaches a certain size. In addition to that added support of custom dateformat and the possibility to fine-tune log level for each python module.
+
+- Make it possible to take into account the current timeline during leader elections (Alexander Kukushkin)
+
+  It could happen that the node is considering itself as a healthiest one although it is currently not on the latest known timeline. In some cases we want to avoid promoting of such node, which could be achieved by setting `check_timeline` parameter to `true` (default behavior remains unchanged).
+
+- Relaxed requirements on superuser credentials
+
+  Libpq allows opening connections without explicitly specifying neither username nor password. Depending on situation it relies either on pgpass file or trust authentication method in pg_hba.conf. Since pg_rewind is also using libpq, it will work the same way.
+
+- Implemented possibility to configure Consul Service registration and check interval via environment variables (Alexander Kukushkin)
+
+  Registration of service in Consul was added in the 1.5.0, but so far it was only possible to turn it on via patroni.yaml.
+
+**Stability Improvements**
+
+- Set archive_mode to off during the custom bootstrap (Alexander Kukushkin)
+
+  We want to avoid archiving wals and history files until the cluster is fully functional.  It really helps if the custom bootstrap involves pg_upgrade.
+
+- Apply five seconds backoff when loading global config on start (Alexander Kukushkin)
+
+  It helps to avoid hammering DCS when Patroni just starting up.
+
+- Reduce amount of error messages generated on shutdown (Alexander Kukushkin)
+
+  They were harmless but rather annoying and sometimes scary.
+
+- Explicitly secure rw perms for recovery.conf at creation time (Lucas)
+
+  We don't want anybody except patroni/postgres user reading this file, because it contains replication user and password.
+
+- Redirect HTTPServer exceptions to logger (Julien Riou)
+
+  By default, such exceptions were logged on standard output messing with regular logs.
+
+**Bug fixes**
+
+- Removed stderr pipe to stdout on pg_ctl process (Cody Coons)
+
+  Inheriting stderr from the main Patroni process allows all Postgres logs to be seen along with all patroni logs. This is very useful in a container environment as Patroni and Postgres logs may be consumed using standard tools (docker logs, kubectl, etc). In addition to that, this change fixes a bug with Patroni not being able to catch postmaster pid when postgres writing some warnings into stderr.
+
+- Set Consul service check deregister timeout in Go time format (Pavel Kirillov)
+
+  Without explicitly mentioned time unit registration was failing.
+
+- Relax checks of standby_cluster cluster configuration (Dmitry Dolgov, Alexander Kukushkin)
+
+  It was accepting only strings as valid values and therefore it was not possible to specify the port as integer and create_replica_methods as a list.
+
+Version 1.5.3
+-------------
+
+Compatibility and bugfix release.
+
+- Improve stability when running with python3 against zookeeper (Alexander Kukushkin)
+
+  Change of `loop_wait` was causing Patroni to disconnect from zookeeper and never reconnect back.
+
+- Fix broken compatibility with postgres 9.3 (Alexander)
+
+  When opening a replication connection we should specify replication=1, beacuse 9.3 does not understand replication='database'
+
+- Make sure we refresh Consul session at least once per HA loop and improve handling of consul sessions exceptions (Alexander)
+
+  Restart of local consul agent invalidates all sessions related to the node. Not calling session refresh on time and not doing proper handling of session errors was causing demote of the primary.
+
+Version 1.5.2
+-------------
+
+Compatibility and bugfix release.
+
+- Compatibility with kazoo-2.6.0 (Alexander Kukushkin)
+
+  In order to make sure that requests are performed with an appropriate timeout, Patroni redefines create_connection method from python-kazoo module. The last release of kazoo slightly changed the way how create_connection method is called.
+
+- Fix Patroni crash when Consul cluster loses the leader (Alexander)
+
+  The crash was happening due to incorrect implementation of touch_member method, it should return boolean and not raise any exceptions.
+
+Version 1.5.1
+-------------
+
+This version implements support of permanent replication slots, adds support of pgBackRest and fixes number of bugs.
+
+**New features**
+
+- Permanent replication slots (Alexander Kukushkin)
+
+  Permanent replication slots are preserved on failover/switchover, that is, Patroni on the new primary will create configured replication slots right after doing promote. Slots could be configured with the help of `patronictl edit-config`. The initial configuration could be also done in the :ref:`bootstrap.dcs <settings>`.
+
+- Add pgbackrest support (Yogesh Sharma)
+
+  pgBackrest can restore in existing $PGDATA folder, this allows speedy restore as files which have not changed since last backup are skipped, to support this feature new parameter `keep_data` has been introduced. See :ref:`replica creation method <custom_replica_creation>` section for additional examples.
+
+**Bug fixes**
+
+- A few bugfixes in the "standby cluster" workflow (Alexander)
+
+  Please see https://github.com/zalando/patroni/pull/823 for more details.
+
+- Fix REST API health check when cluster management is paused and DCS is not accessible (Alexander)
+
+  Regression was introduced in https://github.com/zalando/patroni/commit/90cf930036a9d5249265af15d2b787ec7517cf57
+
+Version 1.5.0
+-------------
+
+This version enables Patroni HA cluster to operate in a standby mode, introduces experimental support for running on Windows, and provides a new configuration parameter to register PostgreSQL service in Consul.
+
+**New features**
+
+- Standby cluster (Dmitry Dolgov)
+
+  One or more Patroni nodes can form a standby cluster that runs alongside the primary one (i.e. in another datacenter) and consists of standby nodes that replicate from the master in the primary cluster. All PostgreSQL nodes in the standby cluster are replicas; one of those replicas elects itself to replicate directly from the remote master, while the others replicate from it in a cascading manner. More detailed description of this feature and some configuration examples can be found at :ref:`here <standby_cluster>`.
+
+- Register Services in Consul (Pavel Kirillov, Alexander Kukushkin)
+
+  If `register_service` parameter in the consul :ref:`configuration <consul_settings>` is enabled, the node will register a service with the name `scope` and the tag `master`, `replica` or `standby-leader`.
+
+- Experimental Windows support (Pavel Golub)
+
+  From now on it is possible to run Patroni on Windows, although Windows support is brand-new and hasn't received as much real-world testing as its Linux counterpart. We welcome your feedback!
+
+**Improvements in patronictl**
+
+- Add patronictl -k/--insecure flag and support for restapi cert (Wilfried Roset)
+
+  In the past if the REST API was protected by the self-signed certificates `patronictl` would fail to verify them. There was no way to  disable that verification. It is now possible to configure `patronictl` to skip the certificate verification altogether or provide CA and client certificates in the :ref:`ctl: <patronictl_settings>` section of configuration.
+
+- Exclude members with nofailover tag from patronictl switchover/failover output (Alexander Anikin)
+
+  Previously, those members were incorrectly proposed as candidates when performing interactive switchover or failover via patronictl.
+
+**Stability improvements**
+
+- Avoid parsing non-key-value output lines of pg_controldata (Alexander Anikin)
+
+  Under certain circuimstances pg_controldata outputs lines without a colon character. That would trigger an error in Patroni code that parsed pg_controldata output, hiding the actual problem; often such lines are emitted in a warning shown by pg_controldata before the regular output, i.e. when the binary major version does not match the one of the PostgreSQL data directory.
+
+- Add member name to the error message during the leader election (Jan Mussler)
+
+  During the leader election, Patroni connects to all known members of the cluster and requests their status. Such status is written to the Patroni log and includes the name of the member. Previously, if the member was not accessible, the error message did not indicate its name, containing only the URL.
+
+- Immediately reserve the WAL position upon creation of the replication slot (Alexander Kukushkin)
+
+  Starting from 9.6, `pg_create_physical_replication_slot` function provides an additional boolean parameter `immediately_reserve`. When it is set to `false`, which is also the default, the slot doesn't reserve the WAL position until it receives the first client connection, potentially losing some segments required by the client in a time window between the slot creation and the intiial client connection.
+
+- Fix bug in strict synchronous replication (Alexander Kukushkin)
+
+  When running with `synchronous_mode_strict: true`, in some cases Patroni puts `*` into the `synchronous_standby_names`, changing the sync state for most of the replication connections to `potential`. Previously, Patroni couldn't pick a synchronous candidate under such curcuimstances, as it only considered those with the state `async`.
+
+
+Version 1.4.6
+-------------
+
+**Bug fixes and stability improvements**
+
+This release fixes a critical issue with Patroni API /master endpoint returning 200 for the non-master node. This is a
+reporting issue, no actual split-brain, but under certain circumstances clients might be directed to the read-only node.
+
+- Reset is_leader status on demote (Alexander Kukushkin, Oleksii Kliukin)
+
+  Make sure demoted cluster member stops responding with code 200 on the /master API call.
+
+- Add new "cluster_unlocked" field to the API output (Dmitry Dolgov)
+
+  This field indicates whether the cluster has the master running. It can be used when it is not possible to query any
+  other node but one of the replicas.
+
 Version 1.4.5
 -------------
 
@@ -234,8 +494,8 @@ In addition to using Endpoints, Patroni supports ConfigMaps. You can find more i
 
 - Minimize the amount of SELECT's issued by Patroni on every loop of HA cylce (Alexander Kukushkin)
 
-  On every iteration of HA loop Patroni needs to know recovery status and absolute wal position. From now on Patroni will run only single SELECT to get this information instead of two on the replica and three on the master. 
-  
+  On every iteration of HA loop Patroni needs to know recovery status and absolute wal position. From now on Patroni will run only single SELECT to get this information instead of two on the replica and three on the master.
+
 - Remove leader key on shutdown only when we have the lock (Ants)
 
   Unconditional removal was generating unnecessary and missleading exceptions.
@@ -245,7 +505,7 @@ In addition to using Endpoints, Patroni supports ConfigMaps. You can find more i
 - Add version command to patronictl (Ants)
 
   It will show the version of installed Patroni and versions of running Patroni instances (if the cluster name is specified).
-  
+
 - Make optional specifying cluster_name argument for some of patronictl commands (Alexander, Ants)
 
   It will work if patronictl is using usual Patroni configuration file with the ``scope`` defined.
@@ -253,11 +513,11 @@ In addition to using Endpoints, Patroni supports ConfigMaps. You can find more i
 - Show information about scheduled switchover and maintenance mode (Alexander)
 
   Before that it was possible to get this information only from Patroni logs or directly from DCS.
-  
+
 - Improve ``patronictl reinit`` (Alexander)
 
   Sometimes ``patronictl reinit`` refused to proceed when Patroni was busy with other actions, namely trying to start postgres. `patronictl` didn't provide any commands to cancel such long running actions and the only (dangerous) workarond was removing a data directory manually. The new implementation of `reinit` forcefully cancells other long-running actions before proceeding with reinit.
-  
+
 - Implement ``--wait`` flag in ``patronictl pause`` and ``patronictl resume`` (Alexander)
 
   It will make ``patronictl`` wait until the requested action is acknowledged by all nodes in the cluster.
@@ -304,7 +564,7 @@ Version 1.3.6
   After a crash that doesn't clean up postmaster.pid there could be a new process with the same pid, resulting in a false positive for is_running(), which will lead to all kinds of bad behavior.
 
 - Shutdown postgresql before bootstrap when we lost data directory (ainlolcat)
-  
+
   When data directory on the master is forcefully removed, postgres process can still stay alive for some time and prevent the replica created in place of that former master from starting or replicating.
   The fix makes Patroni cache the postmaster pid and its start time and let it terminate the old postmaster in case it is still running after the corresponding data directory has been removed.
 
@@ -374,7 +634,7 @@ Version 1.3.4
 - Pass the consul token as a header (Andrew Colin Kissa)
 
   Headers are now the prefered way to pass the token to the consul `API <https://www.consul.io/api/index.html#authentication>`__.
-  
+
 
 - Advanced configuration for Consul (Alexander Kukushkin)
 

docs/replica_bootstrap.rst

@@ -65,6 +65,19 @@ for outdated backup files. Some people prefer other backup solutions, such as ``
 others, or simply roll their own scripts. In order to accommodate all those use-cases Patroni supports running custom
 scripts to clone a new replica. Those are configured in the ``postgresql`` configuration block:
 
+.. code:: YAML
+
+    postgresql:
+        create_replica_methods:
+            - <method name>
+        <method name>:
+            command: <command name>
+            keep_data: True
+            no_params: True
+            no_master: 1
+
+example: wal_e
+
 .. code:: YAML
 
     postgresql:
@@ -79,6 +92,21 @@ scripts to clone a new replica. Those are configured in the ``postgresql`` confi
         basebackup:
             max-rate: '100M'
 
+example: pgbackrest
+
+.. code:: YAML
+
+    postgresql:
+        create_replica_methods:
+            - pgbackrest
+            - basebackup
+        pgbackrest:
+            command: /usr/bin/pgbackrest --stanza=<scope> --delta restore
+            keep_data: True
+            no_params: True
+        basebackup:
+            max-rate: '100M'
+
 
 The ``create_replica_methods`` defines available replica creation methods and the order of executing them. Patroni will
 stop on the first one that returns 0. Each method should define a separate section in the configuration file, listing the command
@@ -99,6 +127,10 @@ 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 ``no_params`` parameter, if defined, restricts passing parameters to custom command.
+
 A ``basebackup`` method is a special case: it will be used if
 ``create_replica_methods`` is empty, although it is possible
 to list it explicitly among the ``create_replica_methods`` methods. This method initializes a new replica with the
@@ -129,3 +161,47 @@ and
             - max-rate: '100M'
 
 If all replica creation methods fail, Patroni will try again all methods in order during the next event loop cycle.
+
+.. _standby_cluster:
+
+Standby cluster
+---------------
+
+Another available option is to run a "standby cluster", that contains only of
+standby nodes replicating from some remote master. This type of clusters has:
+
+* "standby leader", that behaves pretty much like a regular cluster leader,
+  except it replicates from a remote master.
+
+* cascade replicas, that are replicating from standby leader.
+
+Standby leader holds and updates a leader lock in DCS. If the leader lock
+expires, cascade replicas will perform an election to choose another leader
+from the standbys.
+
+For the sake of flexibility, you can specify methods of creating a replica and
+recovery WAL records when a cluster is in the "standby mode" by providing
+`create_replica_methods` key in `standby_cluster` section. It is distinct from
+creating replicas, when cluster is detached and functions as a normal cluster,
+which is controlled by `create_replica_methods` in `postgresql` section. Both
+"standby" and "normal" `create_replica_methods` reference  keys in `postgresql`
+section.
+
+To configure such cluster you need to specify the section ``standby_cluster``
+in a patroni configuration:
+
+.. code:: YAML
+
+    bootstrap:
+        dcs:
+            standby_cluster:
+                host: 1.2.3.4
+                port: 5432
+                primary_slot_name: patroni
+                create_replica_methods:
+                - basebackup
+
+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.

docs/replication_modes.rst

@@ -13,6 +13,8 @@ In asynchronous mode the cluster is allowed to lose some committed transactions
 
 The amount of transactions that can be lost is controlled via ``maximum_lag_on_failover`` parameter. Because the primary transaction log position is not sampled in real time, in reality the amount of lost data on failover is worst case bounded by  ``maximum_lag_on_failover`` bytes of transaction log plus the amount that is written in the last ``ttl`` seconds (``loop_wait``/2 seconds in the average case). However typical steady state replication delay is well under a second.
 
+By default, when running leader elections, Patroni does not take into account the current timeline of replicas, what in some cases could be undesirable behavior. You can prevent the node not having the same timeline as a former master become the new leader by changing the value of ``check_timeline`` parameter to ``true``.
+
 PostgreSQL synchronous replication
 ----------------------------------
 

extras/README.md

@@ -1,11 +1,11 @@
 ### confd
 
-`confd` directory contains haproxy template files for the [confd](https://github.com/kelseyhightower/confd) -- lightweight configuration management tool
+`confd` directory contains haproxy and pgbouncer template files for the [confd](https://github.com/kelseyhightower/confd) -- lightweight configuration management tool
 You need to copy content of `confd` directory into /etcd/confd and run confd service:
 ```bash
 $ confd -prefix=/service/$PATRONI_SCOPE -backend etcd -node $PATRONI_ETCD_URL -interval=10
 ```
-It will periodically update haproxy.cfg with the actual list of Patroni nodes from `etcd` and "reload" haproxy when it is necessary.
+It will periodically update haproxy.cfg and pgbouncer.ini with the actual list of Patroni nodes from `etcd` and "reload" haproxy and pgbouncer.ini when it is necessary.
 
 
 ### startup-scripts

extras/confd/conf.d/pgbouncer.toml

@@ -0,0 +1,12 @@
+[template]
+prefix = "/service/batman"
+owner = "postgres"
+mode = "0644"
+src = "pgbouncer.tmpl"
+dest = "/etc/pgbouncer/pgbouncer.ini"
+
+reload_cmd = "systemctl reload pgbouncer"
+
+keys = [
+    "/members/","/leader"
+]

extras/confd/templates/pgbouncer.tmpl

@@ -0,0 +1,17 @@
+[databases]
+{{with get "/leader"}}{{$leader := .Value}}{{$leadkey := printf "/members/%s" $leader}}{{with get $leadkey}}{{$data := json .Value}}{{$hostport := base (replace (index (split $data.conn_url "/") 2) "@" "/" -1)}}{{ $host := base (index (split $hostport ":") 0)}}{{ $port := base (index (split $hostport ":") 1)}}* = host={{ $host }} port={{ $port }} pool_size=10{{end}}{{end}}
+
+[pgbouncer]
+logfile = /var/log/postgresql/pgbouncer.log
+pidfile = /var/run/postgresql/pgbouncer.pid
+listen_addr = *
+listen_port = 6432
+unix_socket_dir = /var/run/postgresql
+auth_type = trust
+auth_file = /etc/pgbouncer/userlist.txt
+auth_hba_file = /etc/pgbouncer/pg_hba.txt
+admin_users = pgbouncer
+stats_users = pgbouncer
+pool_mode = session
+max_client_conn = 100
+default_pool_size = 20

extras/startup-scripts/patroni.service

@@ -18,8 +18,14 @@ WorkingDirectory=~
 
 # Where to send early-startup messages from the server
 # This is normally controlled by the global default set by systemd
-# StandardOutput=syslog
+#StandardOutput=syslog
 
+# Pre-commands to start watchdog device
+# Uncomment if watchdog is part of your patroni setup
+#ExecStartPre=-/usr/bin/sudo /sbin/modprobe softdog
+#ExecStartPre=-/usr/bin/sudo /bin/chown postgres /dev/watchdog
+
+# Start the patroni process
 ExecStart=/bin/patroni /etc/patroni.yml
 
 # Send HUP to reload from patroni.yml

features/basic_replication.feature

@@ -14,11 +14,13 @@ Feature: basic replication
     Then table foo is present on postgres2 after 20 seconds
 
   Scenario: check restart of sync replica
-    Given I run patronictl.py restart batman postgres2 --force
-    And "sync" key in DCS has sync_standby=postgres1 after 2 seconds
-    And I run patronictl.py restart batman postgres1 --force
-    Then I receive a response returncode 0
-    And "sync" key in DCS has sync_standby=postgres2 after 10 seconds
+    Given I shut down postgres2
+    Then "sync" key in DCS has sync_standby=postgres1 after 5 seconds
+    When I start postgres2
+    And I shut down postgres1
+    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
     And I sleep for 2 seconds
     When I issue a GET request to http://127.0.0.1:8010/sync
     Then I receive a response code 200
@@ -30,7 +32,7 @@ Feature: basic replication
     Then I receive a response returncode 0
     When I sleep for 2 seconds
     And I shut down postgres0
-    And I run patronictl.py resume batman 
+    And I run patronictl.py resume batman
     Then I receive a response returncode 0
     And postgres2 role is the primary after 24 seconds
     When I issue a PATCH request to http://127.0.0.1:8010/config with {"synchronous_mode": null, "master_start_timeout": 0}

features/callback.sh

@@ -0,0 +1,5 @@
+#!/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/environment.py

@@ -12,6 +12,7 @@ import shutil
 import signal
 import six
 import subprocess
+import sys
 import tempfile
 import threading
 import time
@@ -84,7 +85,7 @@ class AbstractController(object):
 
 
 class PatroniController(AbstractController):
-    __PORT = 5440
+    __PORT = 5360
     PATRONI_CONFIG = '{}.yml'
     """ starts and stops individual patronis"""
 
@@ -110,19 +111,31 @@ class PatroniController(AbstractController):
         with open(os.path.join(self._data_dir, 'label'), 'w') as f:
             f.write(content)
 
-    def read_label(self):
+    def read_label(self, label):
         try:
-            with open(os.path.join(self._data_dir, 'label'), 'r') as f:
+            with open(os.path.join(self._data_dir, label), 'r') as f:
                 return f.read().strip()
         except IOError:
             return None
 
-    def add_tag_to_config(self, tag, value):
+    @staticmethod
+    def recursive_update(dst, src):
+        for k, v in src.items():
+            if k in dst and isinstance(dst[k], dict):
+                PatroniController.recursive_update(dst[k], v)
+            else:
+                dst[k] = v
+
+    def update_config(self, custom_config):
         with open(self._config) as r:
             config = yaml.safe_load(r)
-            config['tags']['tag'] = value
+            self.recursive_update(config, custom_config)
             with open(self._config, 'w') as w:
                 yaml.safe_dump(config, w, default_flow_style=False)
+        self._scope = config.get('scope', 'batman')
+
+    def add_tag_to_config(self, tag, value):
+        self.update_config({'tags': {tag: value}})
 
     def _start(self):
         if self.watchdog:
@@ -130,7 +143,8 @@ class PatroniController(AbstractController):
         if isinstance(self._context.dcs_ctl, KubernetesController):
             self._context.dcs_ctl.create_pod(self._name[8:], self._scope)
             os.environ['PATRONI_KUBERNETES_POD_IP'] = '10.0.0.' + self._name[-1]
-        return subprocess.Popen(['coverage', 'run', '--source=patroni', '-p', 'patroni.py', self._config],
+        return subprocess.Popen([sys.executable, '-m', 'coverage', 'run',
+                                '--source=patroni', '-p', 'patroni.py', self._config],
                                 stdout=self._log, stderr=subprocess.STDOUT, cwd=self._work_directory)
 
     def stop(self, kill=False, timeout=15, postgres=False):
@@ -174,13 +188,10 @@ class PatroniController(AbstractController):
                 config['bootstrap']['initdb'].extend([{'auth': 'md5'}, {'auth-host': 'md5'}])
 
         if custom_config is not None:
-            def recursive_update(dst, src):
-                for k, v in src.items():
-                    if k in dst and isinstance(dst[k], dict):
-                        recursive_update(dst[k], v)
-                    else:
-                        dst[k] = v
-            recursive_update(config, custom_config)
+            self.recursive_update(config, custom_config)
+
+        if config['postgresql'].get('callbacks', {}).get('on_role_change'):
+            config['postgresql']['callbacks']['on_role_change'] += ' ' + str(self.__PORT)
 
         with open(patroni_config_path, 'w') as f:
             yaml.safe_dump(config, f, default_flow_style=False)
@@ -363,6 +374,7 @@ class ConsulController(AbstractDcsController):
     def __init__(self, context):
         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
 
@@ -799,8 +811,8 @@ def before_all(context):
 
 def after_all(context):
     context.dcs_ctl.stop()
-    subprocess.call(['coverage', 'combine'])
-    subprocess.call(['coverage', 'report'])
+    subprocess.call([sys.executable, '-m', 'coverage', 'combine'])
+    subprocess.call([sys.executable, '-m', 'coverage', 'report'])
 
 
 def before_feature(context, feature):
@@ -813,3 +825,5 @@ def after_feature(context, feature):
     context.pctl.stop_all()
     shutil.rmtree(os.path.join(context.pctl.patroni_path, 'data'))
     context.dcs_ctl.cleanup_service_tree()
+    if feature.status == 'failed':
+        shutil.copytree(context.pctl.output_dir, context.pctl.output_dir + '_failed')

features/patroni_api.feature

@@ -43,7 +43,7 @@ Scenario: check dynamic configuration change via DCS
 	And I receive a response loop_wait 2
 	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 {'tag': 'new_value'}
+	And I receive a response tags {'new_tag': 'new_value'}
 
 Scenario: check API requests for the primary-replica pair in the pause mode
 	Given I run patronictl.py pause batman
@@ -71,6 +71,14 @@ 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
+	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
+	Then I receive a response code 200
+	When I issue a GET request to http://127.0.0.1:8009/master
+	Then I receive a response code 200
+	When I issue a GET request to http://127.0.0.1:8009/replica
+	Then I receive a response code 503
 
 Scenario: check the scheduled switchover
 	Given I issue a scheduled switchover from postgres1 to postgres0 in 3 seconds
@@ -84,6 +92,14 @@ 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
+	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
+	Then I receive a response code 503
+	When I issue a GET request to http://127.0.0.1:8009/master
+	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"}}}

features/standby_cluster.feature

@@ -0,0 +1,47 @@
+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
+    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
+    And I sleep for 3 seconds
+    When I issue a PATCH request to http://127.0.0.1:8009/config with {"slots": {"test_logical": {"type": "logical", "database": "postgres", "plugin": "test_decoding"}}}
+    Then I receive a response code 200
+    When I start postgres0 with callback configured
+    Then "members/postgres0" key in DCS has state=running after 10 seconds
+    And replication works from postgres1 to postgres0 after 15 seconds
+    When I shut down postgres1
+    Then postgres0 is a leader after 10 seconds
+    And "members/postgres0" key in DCS has role=master after 3 seconds
+    When I issue a GET request to http://127.0.0.1:8008/
+    Then I receive a response code 200
+    And there is a label with "test_logical" in postgres0 data directory
+
+  Scenario: check replication of a single table in a standby cluster
+    Given I start postgres1 in a standby cluster batman1 as a clone of postgres0
+    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
+    When I issue a GET request to http://127.0.0.1:8009/master
+    Then I receive a response code 200
+    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
+    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
+
+  Scenario: check failover
+    When I kill postgres1
+    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
+    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
+    And replication works from postgres0 to postgres2 after 15 seconds
+    And there is a postgres2_cb.log with "on_start replica batman1\non_role_change standby_leader batman1" in postgres2 data directory

features/steps/cascading_replication.py

@@ -9,9 +9,10 @@ def start_patroni_with_a_name_value_tag(context, name, tag_name, tag_value):
     return context.pctl.start(name, custom_config={'tags': {tag_name: tag_value}})
 
 
-@then('There is a label with "{content:w}" in {name:w} data directory')
-def check_label(context, content, name):
-    label = context.pctl.read_label(name)
+@then('There is a {label} with "{content}" in {name:w} data directory')
+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)
 
 

features/steps/patroni_api.py

@@ -5,6 +5,7 @@ import parse
 import requests
 import shlex
 import subprocess
+import sys
 import time
 import yaml
 
@@ -95,7 +96,7 @@ def do_request(context, request_method, url, data):
 
 @step('I run {cmd}')
 def do_run(context, cmd):
-    cmd = ['coverage', 'run', '--source=patroni', '-p'] + shlex.split(cmd)
+    cmd = [sys.executable, '-m', 'coverage', 'run', '--source=patroni', '-p'] + shlex.split(cmd)
     try:
         # XXX: Dirty hack! We need to take name/passwd from the config!
         env = os.environ.copy()

features/steps/standby_cluster.py

@@ -0,0 +1,78 @@
+import os
+import time
+
+from behave import step
+
+
+select_replication_query = """
+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' -- "
+
+
+@step('I start {name:w} with callback configured')
+def start_patroni_with_callbacks(context, name):
+    return context.pctl.start(name, custom_config={
+        "postgresql": {
+            "callbacks": {
+                "on_role_change": "features/callback.sh"
+            }
+        }
+    })
+
+
+@step('I start {name:w} in a cluster {cluster_name:w}')
+def start_patroni(context, name, cluster_name):
+    return context.pctl.start(name, custom_config={
+        "scope": cluster_name,
+        "postgresql": {
+            "callbacks": {c: callback + name for c in ('on_start', 'on_stop', 'on_restart', 'on_role_change')}
+        }
+    })
+
+
+@step('I start {name:w} in a standby cluster {cluster_name:w} as a clone of {name2:w}')
+def start_patroni_standby_cluster(context, name, cluster_name, name2):
+    # we need to remove patroni.dynamic.json in order to "bootstrap" standby cluster with existing PGDATA
+    os.unlink(os.path.join(context.pctl._processes[name]._data_dir, 'patroni.dynamic.json'))
+    port = context.pctl._processes[name2]._connkwargs.get('port')
+    context.pctl._processes[name].update_config({
+        "scope": cluster_name,
+        "bootstrap": {
+            "dcs": {
+                "ttl": 20,
+                "loop_wait": 2,
+                "retry_timeout": 5,
+                "standby_cluster": {
+                    "host": "localhost",
+                    "port": port,
+                    "primary_slot_name": "pm_1",
+                }
+            }
+        },
+        "postgresql": {
+            "callbacks": {c: callback + name for c in ('on_start', 'on_stop', 'on_restart', 'on_role_change')}
+        }
+    })
+    return context.pctl.start(name)
+
+
+@step('{pg_name1:w} is replicating from {pg_name2:w} after {timeout:d} seconds')
+def check_replication_status(context, pg_name1, pg_name2, timeout):
+    bound_time = time.time() + timeout
+
+    while time.time() < bound_time:
+        cur = context.pctl.query(
+            pg_name2,
+            select_replication_query.format(pg_name1),
+            fail_ok=True
+        )
+
+        if cur and len(cur.fetchall()) != 0:
+            break
+
+        time.sleep(1)
+    else:
+        assert False, "{0} is not replicating from {1} after {2} seconds".format(pg_name1, pg_name2, timeout)

kubernetes/Dockerfile

@@ -1,32 +1,34 @@
-FROM postgres:9.6
+FROM postgres:11
 MAINTAINER Alexander Kukushkin <[email protected]>
 
 RUN export DEBIAN_FRONTEND=noninteractive \
     && echo 'APT::Install-Recommends "0";\nAPT::Install-Suggests "0";' > /etc/apt/apt.conf.d/01norecommend \
     && apt-get update -y \
     && apt-get upgrade -y \
-    && apt-get install -y git curl jq python-psycopg2 python-yaml python-requests python-six python-pysocks \
-        python-dateutil python-pip python-prettytable python-wheel python-psutil python locales \
-
+    && apt-cache depends patroni | sed -n -e 's/.* Depends: \(python3-.\+\)$/\1/p' \
+            | grep -Ev '^python3-(sphinx|etcd|consul|kazoo|kubernetes)' \
+            | xargs apt-get install -y vim-tiny curl jq locales git python3-pip python3-wheel \
     ## Make sure we have a en_US.UTF-8 locale available
     && localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8 \
-
-    && pip install setuptools pip --upgrade \
-    && pip install 'git+https://github.com/zalando/patroni.git#egg=patroni[kubernetes]' \
-
-    && mkdir -p /home/postgres \
-    && chown postgres:postgres /home/postgres \
-
+    && pip3 install setuptools \
+    && pip3 install 'git+https://github.com/zalando/patroni.git#egg=patroni[kubernetes]' \
+    && PGHOME=/home/postgres \
+    && mkdir -p $PGHOME \
+    && chown postgres $PGHOME \
+    && sed -i "s|/var/lib/postgresql.*|$PGHOME:/bin/bash|" /etc/passwd \
+    # Set permissions for OpenShift
+    && chmod 775 $PGHOME \
+    && chmod 664 /etc/passwd \
     # Clean up
-    && apt-get remove -y git python-pip python-setuptools \
+    && apt-get remove -y git python3-pip python3-wheel \
     && apt-get autoremove -y \
     && apt-get clean -y \
     && rm -rf /var/lib/apt/lists/* /root/.cache
 
-ADD entrypoint.sh callback.py /
+ADD entrypoint.sh /
 
 EXPOSE 5432 8008
-ENV LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8
+ENV LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8 EDITOR=/usr/bin/editor
 USER postgres
 WORKDIR /home/postgres
 CMD ["/bin/bash", "/entrypoint.sh"]

kubernetes/callback.py

@@ -1,62 +0,0 @@
-#!/usr/bin/env python
-
-import logging
-import os
-import socket
-import sys
-import time
-
-from kubernetes import client as k8s_client, config as k8s_config
-from urllib3.exceptions import HTTPError
-from six.moves.http_client import HTTPException
-
-logger = logging.getLogger(__name__)
-
-
-class CoreV1Api(k8s_client.CoreV1Api):
-
-    def retry(func):
-        def wrapped(*args, **kwargs):
-            count = 0
-            while True:
-                try:
-                    return func(*args, **kwargs)
-                except (HTTPException, HTTPError, socket.error, socket.timeout):
-                    if count >= 10:
-                        raise
-                    logger.info('Throttling API requests...')
-                    time.sleep(2 ** count * 0.5)
-                    count += 1
-        return wrapped
-
-    @retry
-    def patch_namespaced_endpoints(self, *args, **kwargs):
-        return super(CoreV1Api, self).patch_namespaced_endpoints(*args, **kwargs)
-
-
-def patch_master_endpoint(api, namespace, cluster):
-    addresses = [k8s_client.V1EndpointAddress(ip=os.environ['POD_IP'])]
-    ports = [k8s_client.V1EndpointPort(port=5432)]
-    subsets = [k8s_client.V1EndpointSubset(addresses=addresses, ports=ports)]
-    body = k8s_client.V1Endpoints(subsets=subsets)
-    return api.patch_namespaced_endpoints(cluster, namespace, body)
-
-
-def main():
-    logging.basicConfig(format='%(asctime)s %(levelname)s: %(message)s', level=logging.INFO)
-    if len(sys.argv) != 4 or sys.argv[1] not in ('on_start', 'on_stop', 'on_role_change'):
-        sys.exit('Usage: %s <action> <role> <cluster_name>', sys.argv[0])
-
-    action, role, cluster = sys.argv[1:4]
-
-    k8s_config.load_incluster_config()
-    k8s_api = CoreV1Api()
-
-    namespace = os.environ['KUBERNETES_NAMESPACE']
-
-    if role == 'master' and action in ('on_start', 'on_role_change'):
-        patch_master_endpoint(k8s_api, namespace, cluster)
-
-
-if __name__ == '__main__':
-    main()

kubernetes/entrypoint.sh

@@ -1,5 +1,12 @@
 #!/bin/bash
 
+if [[ $UID -ge 10000 ]]; then
+    GID=$(id -g)
+    sed -e "s/^postgres:x:[^:]*:[^:]*:/postgres:x:$UID:$GID:/" /etc/passwd > /tmp/passwd
+    cat /tmp/passwd > /etc/passwd
+    rm /tmp/passwd
+fi
+
 cat > /home/postgres/patroni.yml <<__EOF__
 bootstrap:
   dcs:
@@ -13,24 +20,20 @@ bootstrap:
   - data-checksums
   pg_hba:
   - host all all 0.0.0.0/0 md5
-  - host replication ${PATRONI_REPLICATION_USERNAME} ${POD_IP}/16    md5
+  - host replication ${PATRONI_REPLICATION_USERNAME} ${PATRONI_KUBERNETES_POD_IP}/16 md5
 restapi:
-  connect_address: '${POD_IP}:8008'
+  connect_address: '${PATRONI_KUBERNETES_POD_IP}:8008'
 postgresql:
-  connect_address: '${POD_IP}:5432'
+  connect_address: '${PATRONI_KUBERNETES_POD_IP}:5432'
   authentication:
     superuser:
       password: '${PATRONI_SUPERUSER_PASSWORD}'
     replication:
       password: '${PATRONI_REPLICATION_PASSWORD}'
-  callbacks:
-    on_start: /callback.py
-    on_stop: /callback.py
-    on_role_change: /callback.py
 __EOF__
 
 unset PATRONI_SUPERUSER_PASSWORD PATRONI_REPLICATION_PASSWORD
 export KUBERNETES_NAMESPACE=$PATRONI_KUBERNETES_NAMESPACE
 export POD_NAME=$PATRONI_NAME
 
-exec /usr/bin/python /usr/local/bin/patroni /home/postgres/patroni.yml
+exec /usr/bin/python3 /usr/local/bin/patroni /home/postgres/patroni.yml

kubernetes/openshift-example/README.md

@@ -0,0 +1,49 @@
+# Patroni OpenShift Configuration
+Patroni can be run in OpenShift. Based on the kubernetes configuration, the Dockerfile and Entrypoint has been modified to support the dynamic UID/GID configuration that is applied in OpenShift. This can be run under the standard `restricted` SCC. 
+
+# Examples
+
+## Create test project
+
+```
+oc new-project patroni-test
+```
+
+## Build the image
+
+Note: Update the references when merged upstream. 
+Note: If deploying as a template for multiple users, the following commands should be performed in a shared namespace like `openshift`. 
+
+```
+oc import-image postgres:10 --confirm -n openshift
+oc new-build https://github.com/zalando/patroni --context-dir=kubernetes -n openshift
+```
+
+## Deploy the Image 
+Two configuration templates exist in [templates](templates) directory: 
+- Patroni Ephemeral
+- Patroni Persistent
+
+The only difference is whether or not the statefulset requests persistent storage. 
+
+## Create the Template
+Install the template into the `openshift` namespace if this should be shared across projects: 
+
+```
+oc create -f templates/template_patroni_ephemeral.yml -n openshift
+```
+
+Then, from your own project: 
+
+```
+oc new-app patroni-pgsql-ephemeral
+```
+
+Once the pods are running, two configmaps should be available: 
+
+```
+$ oc get configmap
+NAME                DATA      AGE
+patroniocp-config   0         1m
+patroniocp-leader   0         1m
+```

kubernetes/openshift-example/templates/template_patroni_ephemeral.yml

@@ -0,0 +1,287 @@
+apiVersion: v1
+kind: Template
+metadata:
+  name: patroni-pgsql-ephemeral
+  annotations:
+    description: |-
+      Patroni Postgresql database cluster, without 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 (Ephemeral)
+    openshift.io/long-description: This template deploys a a patroni postgresql HA cluster without persistent storage.
+    tags: postgresql
+objects:
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_CLUSTER_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_MASTER_SERVICE_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    selector:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+      role: master
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: v1
+  kind: Secret
+  metadata:
+    name: ${PATRONI_CLUSTER_NAME}
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+  stringData:
+    superuser-password: ${PATRONI_SUPERUSER_PASSWORD}
+    replication-password: ${PATRONI_REPLICATION_PASSWORD}
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_REPLICA_SERVICE_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    selector:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+      role: replica
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: apps/v1
+  kind: StatefulSet
+  metadata:
+    creationTimestamp: null
+    generation: 3
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${APPLICATION_NAME}
+  spec:
+    podManagementPolicy: OrderedReady
+    replicas: 3
+    revisionHistoryLimit: 10
+    selector:
+      matchLabels:
+        application: ${APPLICATION_NAME}
+        cluster-name: ${PATRONI_CLUSTER_NAME}
+    serviceName: ${APPLICATION_NAME}
+    template:
+      metadata:
+        creationTimestamp: null
+        labels:
+          application: ${APPLICATION_NAME}
+          cluster-name: ${PATRONI_CLUSTER_NAME}
+      spec:
+        containers:
+        - env:
+          - name: PATRONI_KUBERNETES_POD_IP
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: status.podIP
+          - name: PATRONI_KUBERNETES_NAMESPACE
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: metadata.namespace
+          - name: PATRONI_KUBERNETES_LABELS
+            value: '{application: ${APPLICATION_NAME}, cluster-name: ${PATRONI_CLUSTER_NAME}}'
+          - name: PATRONI_SUPERUSER_USERNAME
+            value: ${PATRONI_SUPERUSER_USERNAME}
+          - name: PATRONI_SUPERUSER_PASSWORD
+            valueFrom:
+              secretKeyRef:
+                key: superuser-password
+                name: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_REPLICATION_USERNAME
+            value: ${PATRONI_REPLICATION_USERNAME}
+          - name: PATRONI_REPLICATION_PASSWORD
+            valueFrom:
+              secretKeyRef:
+                key: replication-password
+                name: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_SCOPE
+            value: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_NAME
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: metadata.name
+          - name: PATRONI_POSTGRESQL_DATA_DIR
+            value: /home/postgres/pgdata/pgroot/data
+          - name: PATRONI_POSTGRESQL_PGPASS
+            value: /tmp/pgpass
+          - name: PATRONI_POSTGRESQL_LISTEN
+            value: 0.0.0.0:5432
+          - name: PATRONI_RESTAPI_LISTEN
+            value: 0.0.0.0:8008
+          image: docker-registry.default.svc:5000/${NAMESPACE}/patroni:latest
+          imagePullPolicy: IfNotPresent
+          name: ${APPLICATION_NAME}
+          ports:
+          - containerPort: 8008
+            protocol: TCP
+          - containerPort: 5432
+            protocol: TCP
+          resources: {}
+          terminationMessagePath: /dev/termination-log
+          terminationMessagePolicy: File
+          volumeMounts:
+          - mountPath: /home/postgres/pgdata
+            name: pgdata
+        dnsPolicy: ClusterFirst
+        restartPolicy: Always
+        schedulerName: default-scheduler
+        securityContext: {}
+        serviceAccount: ${SERVICE_ACCOUNT}
+        serviceAccountName: ${SERVICE_ACCOUNT}
+        terminationGracePeriodSeconds: 0
+        volumes:
+        - name: pgdata
+          emptyDir: {}
+    updateStrategy:
+      type: OnDelete
+- apiVersion: v1
+  kind: Endpoints
+  metadata:
+    name: ${APPLICATION_NAME}
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+  subsets: []
+- apiVersion: v1
+  kind: ServiceAccount
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: Role
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+  rules:
+  - apiGroups:
+    - ""
+    resources:
+    - configmaps
+    verbs:
+    - create
+    - get
+    - list
+    - patch
+    - update
+    - watch
+    # delete is required only for 'patronictl remove'
+    - delete
+  - apiGroups:
+    - ""
+    resources:
+    - endpoints
+    verbs:
+    - get
+    - patch
+    - update
+    # the following three privileges are necessary only when using endpoints
+    - create
+    - list
+    - watch
+    # delete is required only for for 'patronictl remove'
+    - delete
+  - apiGroups:
+    - ""
+    resources:
+    - pods
+    verbs:
+    - get
+    - list
+    - patch
+    - update
+    - watch
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: RoleBinding
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+  roleRef:
+    apiGroup: rbac.authorization.k8s.io
+    kind: Role
+    name: ${SERVICE_ACCOUNT}
+  subjects:
+  - kind: ServiceAccount
+    name: ${SERVICE_ACCOUNT}
+parameters:
+- description: The name of the application for labelling all artifacts.
+  displayName: Application Name
+  name: APPLICATION_NAME
+  value: patroni-ephemeral
+- description: The name of the patroni-pgsql cluster.
+  displayName: Cluster Name
+  name: PATRONI_CLUSTER_NAME
+  value: patroni-ephemeral
+- description: The name of the OpenShift Service exposed for the patroni-ephemeral-master container.
+  displayName: Master service name.  
+  name: PATRONI_MASTER_SERVICE_NAME
+  value: patroni-ephemeral-master
+- description: The name of the OpenShift Service exposed for the patroni-ephemeral-replica containers.
+  displayName: Replica service name. 
+  name: PATRONI_REPLICA_SERVICE_NAME
+  value: patroni-ephemeral-replica
+- description: Maximum amount of memory the container can use.
+  displayName: Memory Limit
+  name: MEMORY_LIMIT
+  value: 512Mi
+- description: The OpenShift Namespace where the patroni and postgresql ImageStream resides.
+  displayName: ImageStream Namespace
+  name: NAMESPACE
+  value: openshift
+- description: Username of the superuser account for initialization.
+  displayName: Superuser Username
+  name: PATRONI_SUPERUSER_USERNAME
+  value: postgres
+- description: Password of the superuser account for initialization.
+  displayName: Superuser Passsword
+  name: PATRONI_SUPERUSER_PASSWORD
+  value: postgres
+- description: Username of the replication account for initialization.
+  displayName: Replication Username
+  name: PATRONI_REPLICATION_USERNAME
+  value: postgres
+- description: Password of the replication account for initialization.
+  displayName: Repication Passsword
+  name: PATRONI_REPLICATION_PASSWORD
+  value: postgres
+- description: Service account name used for pods and rolebindings to form a cluster in the project. 
+  displayName: Service Account
+  name: SERVICE_ACCOUNT
+  value: patroniocp

kubernetes/openshift-example/templates/template_patroni_persistent.yaml

@@ -0,0 +1,303 @@
+apiVersion: v1
+kind: Template
+metadata:
+  name: patroni-pgsql-persistent
+  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.
+    tags: postgresql
+objects:
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_CLUSTER_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_MASTER_SERVICE_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    selector:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+      role: master
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: v1
+  kind: Secret
+  metadata:
+    name: ${PATRONI_CLUSTER_NAME}
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+  stringData:
+    superuser-password: ${PATRONI_SUPERUSER_PASSWORD}
+    replication-password: ${PATRONI_REPLICATION_PASSWORD}
+- apiVersion: v1
+  kind: Service
+  metadata:
+    creationTimestamp: null
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${PATRONI_REPLICA_SERVICE_NAME}
+  spec:
+    ports:
+    - port: 5432
+      protocol: TCP
+      targetPort: 5432
+    selector:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+      role: replica
+    sessionAffinity: None
+    type: ClusterIP
+  status:
+    loadBalancer: {}
+- apiVersion: apps/v1
+  kind: StatefulSet
+  metadata:
+    creationTimestamp: null
+    generation: 3
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+    name: ${APPLICATION_NAME}
+  spec:
+    podManagementPolicy: OrderedReady
+    replicas: 3
+    revisionHistoryLimit: 10
+    selector:
+      matchLabels:
+        application: ${APPLICATION_NAME}
+        cluster-name: ${PATRONI_CLUSTER_NAME}
+    serviceName: ${APPLICATION_NAME}
+    template:
+      metadata:
+        creationTimestamp: null
+        labels:
+          application: ${APPLICATION_NAME}
+          cluster-name: ${PATRONI_CLUSTER_NAME}
+      spec:
+        containers:
+        - env:
+          - name: PATRONI_KUBERNETES_POD_IP
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: status.podIP
+          - name: PATRONI_KUBERNETES_NAMESPACE
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: metadata.namespace
+          - name: PATRONI_KUBERNETES_LABELS
+            value: '{application: ${APPLICATION_NAME}, cluster-name: ${PATRONI_CLUSTER_NAME}}'
+          - name: PATRONI_SUPERUSER_USERNAME
+            value: ${PATRONI_SUPERUSER_USERNAME}
+          - name: PATRONI_SUPERUSER_PASSWORD
+            valueFrom:
+              secretKeyRef:
+                key: superuser-password
+                name: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_REPLICATION_USERNAME
+            value: ${PATRONI_REPLICATION_USERNAME}
+          - name: PATRONI_REPLICATION_PASSWORD
+            valueFrom:
+              secretKeyRef:
+                key: replication-password
+                name: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_SCOPE
+            value: ${PATRONI_CLUSTER_NAME}
+          - name: PATRONI_NAME
+            valueFrom:
+              fieldRef:
+                apiVersion: v1
+                fieldPath: metadata.name
+          - name: PATRONI_POSTGRESQL_DATA_DIR
+            value: /home/postgres/pgdata/pgroot/data
+          - name: PATRONI_POSTGRESQL_PGPASS
+            value: /tmp/pgpass
+          - name: PATRONI_POSTGRESQL_LISTEN
+            value: 0.0.0.0:5432
+          - name: PATRONI_RESTAPI_LISTEN
+            value: 0.0.0.0:8008
+          image: docker-registry.default.svc:5000/${NAMESPACE}/patroni:latest
+          imagePullPolicy: IfNotPresent
+          name: ${APPLICATION_NAME}
+          ports:
+          - containerPort: 8008
+            protocol: TCP
+          - containerPort: 5432
+            protocol: TCP
+          resources: {}
+          terminationMessagePath: /dev/termination-log
+          terminationMessagePolicy: File
+          volumeMounts:
+          - mountPath: /home/postgres/pgdata
+            name: ${APPLICATION_NAME}
+        dnsPolicy: ClusterFirst
+        restartPolicy: Always
+        schedulerName: default-scheduler
+        securityContext: {}
+        serviceAccount: ${SERVICE_ACCOUNT}
+        serviceAccountName: ${SERVICE_ACCOUNT}
+        terminationGracePeriodSeconds: 0
+        volumes:
+        - name: ${APPLICATION_NAME}
+          persistentVolumeClaim: 
+            claimName: ${APPLICATION_NAME}
+    volumeClaimTemplates:
+    - metadata:
+        labels:
+          application: ${APPLICATION_NAME}
+        name: ${APPLICATION_NAME}
+      spec:
+        accessModes:
+        - ReadWriteOnce
+        resources:
+          requests:
+            storage: ${PVC_SIZE}
+    updateStrategy:
+      type: OnDelete
+- apiVersion: v1
+  kind: Endpoints
+  metadata:
+    name: ${APPLICATION_NAME}
+    labels:
+      application: ${APPLICATION_NAME}
+      cluster-name: ${PATRONI_CLUSTER_NAME}
+  subsets: []
+- apiVersion: v1
+  kind: ServiceAccount
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: Role
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+  rules:
+  - apiGroups:
+    - ""
+    resources:
+    - configmaps
+    verbs:
+    - create
+    - get
+    - list
+    - patch
+    - update
+    - watch
+    # delete is required only for 'patronictl remove'
+    - delete
+  - apiGroups:
+    - ""
+    resources:
+    - endpoints
+    verbs:
+    - get
+    - patch
+    - update
+    # the following three privileges are necessary only when using endpoints
+    - create
+    - list
+    - watch
+    # delete is required only for for 'patronictl remove'
+    - delete
+  - apiGroups:
+    - ""
+    resources:
+    - pods
+    verbs:
+    - get
+    - list
+    - patch
+    - update
+    - watch
+- apiVersion: rbac.authorization.k8s.io/v1
+  kind: RoleBinding
+  metadata:
+    name: ${SERVICE_ACCOUNT}
+  roleRef:
+    apiGroup: rbac.authorization.k8s.io
+    kind: Role
+    name: ${SERVICE_ACCOUNT}
+  subjects:
+  - kind: ServiceAccount
+    name: ${SERVICE_ACCOUNT}
+parameters:
+- description: The name of the application for labelling all artifacts.
+  displayName: Application Name
+  name: APPLICATION_NAME
+  value: patroni-persistent
+- description: The name of the patroni-pgsql cluster.
+  displayName: Cluster Name
+  name: PATRONI_CLUSTER_NAME
+  value: patroni-persistent
+- description: The name of the OpenShift Service exposed for the patroni-persistent-master container.
+  displayName: Master service name.  
+  name: PATRONI_MASTER_SERVICE_NAME
+  value: patroni-persistent-master
+- description: The name of the OpenShift Service exposed for the patroni-persistent-replica containers.
+  displayName: Replica service name. 
+  name: PATRONI_REPLICA_SERVICE_NAME
+  value: patroni-persistent-replica
+- description: Maximum amount of memory the container can use.
+  displayName: Memory Limit
+  name: MEMORY_LIMIT
+  value: 512Mi
+- description: The OpenShift Namespace where the patroni and postgresql ImageStream resides.
+  displayName: ImageStream Namespace
+  name: NAMESPACE
+  value: openshift
+- description: Username of the superuser account for initialization.
+  displayName: Superuser Username
+  name: PATRONI_SUPERUSER_USERNAME
+  value: postgres
+- description: Password of the superuser account for initialization.
+  displayName: Superuser Passsword
+  name: PATRONI_SUPERUSER_PASSWORD
+  value: postgres
+- description: Username of the replication account for initialization.
+  displayName: Replication Username
+  name: PATRONI_REPLICATION_USERNAME
+  value: postgres
+- description: Password of the replication account for initialization.
+  displayName: Repication Passsword
+  name: PATRONI_REPLICATION_PASSWORD
+  value: postgres
+- description: Service account name used for pods and rolebindings to form a cluster in the project. 
+  displayName: Service Account
+  name: SERVICE_ACCOUNT
+  value: patroni-persistent
+- description: The size of the persistent volume to create. 
+  displayName: Persistent Volume Size
+  name: PVC_SIZE
+  value: 5Gi

kubernetes/openshift-example/test/Jenkinsfile

@@ -0,0 +1,43 @@
+pipeline {
+  agent any
+  stages {
+    stage ('Deploy test pod'){
+      when {
+          expression {
+            openshift.withCluster() {
+              openshift.withProject() {
+                return !openshift.selector( "dc", "pgbench" ).exists()
+              }
+            }
+          }
+        }
+      steps {
+        script {
+            openshift.withCluster() {
+                openshift.withProject() {
+                  def pgbench = openshift.newApp( "https://github.com/stewartshea/docker-pgbench/", "--name=pgbench", "-e PGPASSWORD=postgres", "-e PGUSER=postgres", "-e PGHOST=patroni-persistent-master", "-e PGDATABASE=postgres", "-e TEST_CLIENT_COUNT=20", "-e TEST_DURATION=120" )
+                  def pgbenchdc = openshift.selector( "dc", "pgbench" )
+                  timeout(5) { 
+                    pgbenchdc.rollout().status()
+                    }
+                  }
+                }
+            }
+        }
+    }
+    stage ('Run benchmark Test'){
+      steps {
+          sh '''
+          oc exec $(oc get pods -l app=pgbench | grep Running | awk '{print $1}')  ./test.sh
+          '''
+      }
+    }
+    stage ('Clean up pgtest pod'){
+      steps {
+          sh '''
+          oc delete all -l app=pgbench
+          '''
+      }
+    }
+  }
+}

kubernetes/openshift-example/test/README.md

@@ -0,0 +1,2 @@
+# Jenkins Test
+This pipeline test will create a separate deployment config for a pgbench pod and execute a test against the patroni cluster. This is a sample and should be customized. 

kubernetes/patroni_k8s.yaml

@@ -1,3 +1,15 @@
+# headless service to avoid deletion of patronidemo-config endpoint
+apiVersion: v1
+kind: Service
+metadata:
+  name: patronidemo-config
+  labels:
+    application: patroni
+    cluster-name: patronidemo
+spec:
+  clusterIP: None
+
+---
 apiVersion: apps/v1beta1
 kind: StatefulSet
 metadata:
@@ -28,7 +40,7 @@ spec:
         - mountPath: /home/postgres/pgdata
           name: pgdata
         env:
-        - name: POD_IP
+        - name: PATRONI_KUBERNETES_POD_IP
           valueFrom:
             fieldRef:
               fieldPath: status.podIP
@@ -36,6 +48,8 @@ spec:
           valueFrom:
             fieldRef:
               fieldPath: metadata.namespace
+        - name: PATRONI_KUBERNETES_USE_ENDPOINTS
+          value: 'true'
         - name: PATRONI_KUBERNETES_LABELS
           value: '{application: patroni, cluster-name: patronidemo}'
         - name: PATRONI_SUPERUSER_USERNAME
@@ -171,6 +185,16 @@ rules:
   - patch
   - update
   - watch
+# The following privilege is only necessary for creation of headless service
+# for patronidemo-config endpoint, in order to prevent cleaning it up by the
+# k8s master. You can avoid giving this privilege by explicitly creating the
+# service like it is done in this manifest (lines 2..10)
+- apiGroups:
+  - ""
+  resources:
+  - services
+  verbs:
+  - create
 
 ---
 apiVersion: rbac.authorization.k8s.io/v1

patroni/__init__.py

@@ -14,6 +14,7 @@ class Patroni(object):
         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.watchdog import Watchdog
@@ -21,7 +22,9 @@ class Patroni(object):
         self.setup_signal_handlers()
 
         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()
@@ -49,6 +52,7 @@ class Patroni(object):
                 break
             except DCSError:
                 logger.warning('Can not get cluster from dcs')
+                time.sleep(5)
 
     def get_tags(self):
         return {tag: value for tag, value in self.config.get('tags', {}).items()
@@ -65,6 +69,7 @@ class Patroni(object):
     def reload_config(self):
         try:
             self.tags = self.get_tags()
+            self.logger.reload_config(self.config.get('log', {}))
             self.dcs.reload_config(self.config)
             self.watchdog.reload_config(self.config)
             self.api.reload_config(self.config['restapi'])
@@ -80,9 +85,10 @@ class Patroni(object):
         self._received_sighup = True
 
     def sigterm_handler(self, *args):
-        if not self._received_sigterm:
-            self._received_sigterm = True
-            sys.exit()
+        with self._sigterm_lock:
+            if not self._received_sigterm:
+                self._received_sigterm = True
+                sys.exit()
 
     @property
     def noloadbalance(self):
@@ -101,11 +107,16 @@ 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()
 
-        while not self._received_sigterm:
+        while not self.received_sigterm:
             if self._received_sighup:
                 self._received_sighup = False
                 if self.config.reload_local_configuration():
@@ -123,12 +134,18 @@ class Patroni(object):
             self.schedule_next_run()
 
     def setup_signal_handlers(self):
+        from threading import Lock
+
         self._received_sighup = False
+        self._sigterm_lock = Lock()
         self._received_sigterm = False
-        signal.signal(signal.SIGHUP, self.sighup_handler)
+        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:
@@ -137,12 +154,6 @@ class Patroni(object):
 
 
 def patroni_main():
-    logformat = os.environ.get('PATRONI_LOGFORMAT', '%(asctime)s %(levelname)s: %(message)s')
-    loglevel = os.environ.get('PATRONI_LOGLEVEL', 'INFO')
-    requests_loglevel = os.environ.get('PATRONI_REQUESTS_LOGLEVEL', 'WARNING')
-    logging.basicConfig(format=logformat, level=loglevel)
-    logging.getLogger('requests').setLevel(requests_loglevel)
-
     patroni = Patroni()
     try:
         patroni.run()
@@ -150,34 +161,14 @@ def patroni_main():
         pass
     finally:
         patroni.shutdown()
-
-
-def pg_ctl_start(args):
-    import subprocess
-    postmaster = subprocess.Popen(args)
-    print(postmaster.pid)
-
-
-def call_self(args, **kwargs):
-    """This function executes Patroni once again with provided arguments.
-
-    :args: list of arguments to call Patroni with.
-    :returns: `Popen` object"""
-
-    exe = [sys.executable]
-    if not getattr(sys, 'frozen', False):  # Binary distribution?
-        exe.append(sys.argv[0])
-
-    import subprocess
-    return subprocess.Popen(exe + args, **kwargs)
+        logging.shutdown()
 
 
 def main():
     if os.getpid() != 1:
-        if len(sys.argv) > 5 and sys.argv[1] == 'pg_ctl_start':
-            return pg_ctl_start(sys.argv[2:])
         return patroni_main()
 
+    # Patroni started with PID=1, it looks like we are in the container
     pid = 0
 
     # Looks like we are in a docker, so we will act like init
@@ -188,7 +179,7 @@ def main():
                 if ret == (0, 0):
                     break
                 elif ret[0] != pid:
-                    logging.info('Reaped pid=%s, exit status=%s', *ret)
+                    logger.info('Reaped pid=%s, exit status=%s', *ret)
         except OSError:
             pass
 
@@ -196,14 +187,18 @@ def main():
         if pid:
             os.kill(pid, signo)
 
-    signal.signal(signal.SIGCHLD, sigchld_handler)
-    signal.signal(signal.SIGHUP, passtochild)
+    if os.name != 'nt':
+        signal.signal(signal.SIGCHLD, sigchld_handler)
+        signal.signal(signal.SIGHUP, passtochild)
+        signal.signal(signal.SIGQUIT, passtochild)
+        signal.signal(signal.SIGUSR1, passtochild)
+        signal.signal(signal.SIGUSR2, passtochild)
     signal.signal(signal.SIGINT, passtochild)
-    signal.signal(signal.SIGUSR1, passtochild)
-    signal.signal(signal.SIGUSR2, passtochild)
-    signal.signal(signal.SIGQUIT, passtochild)
+    signal.signal(signal.SIGABRT, passtochild)
     signal.signal(signal.SIGTERM, passtochild)
 
-    patroni = call_self(sys.argv[1:])
+    import multiprocessing
+    patroni = multiprocessing.Process(target=patroni_main)
+    patroni.start()
     pid = patroni.pid
-    patroni.wait()
+    patroni.join()

patroni/api.py

@@ -1,11 +1,12 @@
 import base64
-import fcntl
 import json
 import logging
 import psycopg2
 import time
+import traceback
 import dateutil.parser
 import datetime
+import os
 
 from patroni.postgresql import PostgresConnectionException, PostgresException, Postgresql
 from patroni.utils import deep_compare, parse_bool, patch_config, Retry, \
@@ -84,35 +85,26 @@ class RestApiHandler(BaseHTTPRequestHandler):
         patroni = self.server.patroni
         cluster = patroni.dcs.cluster
 
-        def is_synchronous():
-            return (cluster.is_synchronous_mode() and cluster.sync
-                    and cluster.sync.sync_standby == patroni.postgresql.name)
+        replica_status_code = 200 if not patroni.noloadbalance and response.get('role') == 'replica' else 503
+        status_code = 503
 
-        def is_balanceable_replica():
-            return response.get('role') == 'replica' and not patroni.noloadbalance
-
-        if cluster:  # dcs available
-            if patroni.ha.is_leader():
-                status_code = 200 if 'master' in path else 503
-            elif 'role' not in response:
-                status_code = 503
-            elif response['role'] == 'master':  # running as master but without leader lock!!!!
-                status_code = 503
-            elif path in ('/sync', '/synchronous'):
-                status_code = 200 if is_balanceable_replica() and is_synchronous() else 503
-            elif path in ('/async', '/asynchronous'):
-                status_code = 200 if is_balanceable_replica() and not is_synchronous() else 503
-            elif response['role'] in path:  # response['role'] != 'master'
-                status_code = 503 if patroni.noloadbalance else 200
+        if patroni.ha.is_standby_cluster() and ('standby_leader' in path or 'standby-leader' in path):
+            status_code = 200 if patroni.ha.is_leader() else 503
+        elif 'master' in path or 'leader' in path or 'primary' in path:
+            # Round-robing across all masters in pause mode if DCS is not accessible
+            if not cluster and patroni.ha.is_paused():
+                status_code = 200 if response['role'] == 'master' else 503
             else:
-                status_code = 503
-        elif 'role' in response and response['role'] in path:
-            status_code = 503 if response['role'] != 'master' and patroni.noloadbalance else 200
-        elif patroni.ha.restart_scheduled() and patroni.postgresql.role == 'master' and 'master' in path:
-            # exceptional case for master node when the postgres is being restarted via API
-            status_code = 200
-        else:
-            status_code = 503
+                status_code = 200 if patroni.ha.is_leader() else 503
+        elif 'replica' in path:
+            status_code = replica_status_code
+        elif cluster:  # dcs is available
+            is_synchronous = cluster.is_synchronous_mode() and cluster.sync \
+                    and cluster.sync.sync_standby == patroni.postgresql.name
+            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]
@@ -415,21 +407,26 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
     def get_postgresql_status(self, retry=False):
         try:
+            cluster = self.server.patroni.dcs.cluster
+
             if self.server.patroni.postgresql.state not in ('running', 'restarting', 'starting'):
                 raise RetryFailedError('')
             stmt = ("WITH replication_info AS ("
                     "SELECT usename, application_name, client_addr, state, sync_state, sync_priority"
-                    " FROM pg_stat_replication) SELECT"
-                    " to_char(pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
-                    " CASE WHEN pg_is_in_recovery() THEN 0"
-                    " ELSE ('x' || SUBSTR(pg_{0}file_name(pg_current_{0}_{1}()), 1, 8))::bit(32)::int END,"
-                    " CASE WHEN pg_is_in_recovery() THEN 0"
-                    " ELSE pg_{0}_{1}_diff(pg_current_{0}_{1}(), '0/0')::bigint END,"
-                    " pg_{0}_{1}_diff(COALESCE(pg_last_{0}_receive_{1}(), pg_last_{0}_replay_{1}()), '0/0')::bigint,"
-                    " pg_{0}_{1}_diff(pg_last_{0}_replay_{1}(), '0/0')::bigint,"
-                    " to_char(pg_last_xact_replay_timestamp(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
-                    " pg_is_in_recovery() AND pg_is_{0}_replay_paused(),"
-                    " (SELECT array_to_json(array_agg(row_to_json(ri))) FROM replication_info ri)")
+                    " 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(), "
+                    "(SELECT pg_catalog.array_to_json(pg_catalog.array_agg("
+                    "pg_catalog.row_to_json(ri))) FROM replication_info ri)")
 
             row = self.query(stmt.format(self.server.patroni.postgresql.wal_name,
                                          self.server.patroni.postgresql.lsn_name), retry=retry)[0]
@@ -439,6 +436,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
                 'postmaster_start_time': row[0],
                 'role': 'replica' if row[1] == 0 else 'master',
                 'server_version': self.server.patroni.postgresql.server_version,
+                'cluster_unlocked': bool(not cluster or cluster.is_unlocked()),
                 'xlog': ({
                     'received_location': row[3],
                     'replayed_location': row[4],
@@ -448,10 +446,12 @@ class RestApiHandler(BaseHTTPRequestHandler):
                 })
             }
 
+            if result['role'] == 'replica' and self.server.patroni.ha.is_standby_cluster():
+                result['role'] = self.server.patroni.postgresql.role
+
             if row[1] > 0:
                 result['timeline'] = row[1]
             else:
-                cluster = self.server.patroni.dcs.cluster
                 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)
 
@@ -492,8 +492,10 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
 
     @staticmethod
     def _set_fd_cloexec(fd):
-        flags = fcntl.fcntl(fd, fcntl.F_GETFD)
-        fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC)
+        if os.name != 'nt':
+            import fcntl
+            flags = fcntl.fcntl(fd, fcntl.F_GETFD)
+            fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC)
 
     def check_basic_auth_key(self, key):
         return self.__auth_key == key
@@ -549,3 +551,9 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
                 and self.__initialize(config):
             self.start()
         self.__set_config_parameters(config)
+
+    @staticmethod
+    def handle_error(request, client_address):
+        address, port = client_address
+        logger.warning('Exception happened during processing of request from {}:{}'.format(address, port))
+        logger.warning(traceback.format_exc())

patroni/callback_executor.py

@@ -19,8 +19,13 @@ class CallbackExecutor(Thread):
     def call(self, cmd):
         with self._lock:
             if self._process and self._process.poll() is None:
-                self._process.kill()
-                logger.warning('Killed the old callback process because it was still running: %s', self._cmd)
+                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')
+                    logger.warning('Wait until callback end')
+                    self._process.wait()
         self._cmd = cmd
         self._callback_event.set()
 

patroni/config.py

@@ -1,6 +1,7 @@
 import json
 import logging
 import os
+import shutil
 import sys
 import tempfile
 import yaml
@@ -42,9 +43,19 @@ class Config(object):
     __DEFAULT_CONFIG = {
         'ttl': 30, 'loop_wait': 10, 'retry_timeout': 10,
         'maximum_lag_on_failover': 1048576,
+        'check_timeline': False,
         'master_start_timeout': 300,
         'synchronous_mode': False,
         'synchronous_mode_strict': False,
+        'standby_cluster': {
+            'create_replica_methods': '',
+            'host': '',
+            'port': '',
+            'primary_slot_name': '',
+            'restore_command': '',
+            'archive_cleanup_command': '',
+            'recovery_min_apply_delay': ''
+        },
         'postgresql': {
             'bin_dir': '',
             'use_slots': True,
@@ -114,7 +125,7 @@ class Config(object):
                 with os.fdopen(fd, 'w') as f:
                     fd = None
                     json.dump(self.dynamic_configuration, f)
-                tmpfile = os.rename(tmpfile, self._cache_file)
+                tmpfile = shutil.move(tmpfile, self._cache_file)
                 self._cache_needs_saving = False
             except Exception:
                 logger.exception('Exception when saving file: %s', self._cache_file)
@@ -183,6 +194,10 @@ class Config(object):
                         config['postgresql'][name].update(self._process_postgresql_parameters(value))
                     elif name not in ('connect_address', 'listen', 'data_dir', 'pgpass', 'authentication'):
                         config['postgresql'][name] = deepcopy(value)
+            elif name == 'standby_cluster':
+                for name, value in (value or {}).items():
+                    if name in self.__DEFAULT_CONFIG['standby_cluster']:
+                        config['standby_cluster'][name] = deepcopy(value)
             elif name in config:  # only variables present in __DEFAULT_CONFIG allowed to be overriden from DCS
                 if name in ('synchronous_mode', 'synchronous_mode_strict'):
                     config[name] = value
@@ -202,6 +217,15 @@ class Config(object):
             if value:
                 ret[param] = value
 
+        def _fix_log_env(name, oldname):
+            value = _popenv(oldname)
+            name = Config.PATRONI_ENV_PREFIX + 'LOG_' + name.upper()
+            if value and name not in os.environ:
+                os.environ[name] = value
+
+        for name, oldname in (('level', 'loglevel'), ('format', 'logformat'), ('dateformat', 'log_datefmt')):
+            _fix_log_env(name, oldname)
+
         def _set_section_values(section, params):
             for param in params:
                 value = _popenv(section + '_' + param)
@@ -209,7 +233,23 @@ class Config(object):
                     ret[section][param] = value
 
         _set_section_values('restapi', ['listen', 'connect_address', 'certfile', 'keyfile'])
-        _set_section_values('postgresql', ['listen', 'connect_address', 'data_dir', 'pgpass', 'bin_dir'])
+        _set_section_values('postgresql', ['listen', 'connect_address', 'config_dir', 'data_dir', 'pgpass', 'bin_dir'])
+        _set_section_values('log', ['level', 'format', 'dateformat', 'dir', 'file_size', 'file_num', 'loggers'])
+
+        def _parse_dict(value):
+            if not value.strip().startswith('{'):
+                value = '{{{0}}}'.format(value)
+            try:
+                return yaml.safe_load(value)
+            except Exception:
+                logger.exception('Exception when parsing dict %s', value)
+                return None
+
+        value = ret.get('log', {}).pop('loggers', None)
+        if value:
+            value = _parse_dict(value)
+            if value:
+                ret['log']['loggers'] = value
 
         def _get_auth(name):
             ret = {}
@@ -232,8 +272,6 @@ class Config(object):
         if authentication:
             ret['postgresql']['authentication'] = authentication
 
-        users = {}
-
         def _parse_list(value):
             if not (value.strip().startswith('-') or '[' in value):
                 value = '[{0}]'.format(value)
@@ -245,37 +283,40 @@ class Config(object):
 
         for param in list(os.environ.keys()):
             if param.startswith(Config.PATRONI_ENV_PREFIX):
+                # PATRONI_(ETCD|CONSUL|ZOOKEEPER|EXHIBITOR|...)_(HOSTS?|PORT|..)
                 name, suffix = (param[8:].split('_', 1) + [''])[:2]
-                if name and suffix:
-                    # PATRONI_(ETCD|CONSUL|ZOOKEEPER|EXHIBITOR|...)_(HOSTS?|PORT|..)
-                    if suffix in ('HOST', 'HOSTS', 'PORT', 'SRV', 'URL', 'PROXY', 'CACERT', 'CERT',
-                                  'KEY', 'VERIFY', 'TOKEN', 'CHECKS', 'DC', 'NAMESPACE', 'CONTEXT',
-                                  'USE_ENDPOINTS', 'SCOPE_LABEL', 'ROLE_LABEL', 'POD_IP', 'PORTS', 'LABELS'):
-                        value = os.environ.pop(param)
-                        if suffix == 'PORT':
-                            value = value and parse_int(value)
-                        elif suffix in ('HOSTS', 'PORTS', 'CHECKS'):
-                            value = value and _parse_list(value)
-                        elif suffix == 'LABELS':
-                            if not value.strip().startswith('{'):
-                                value = '{{{0}}}'.format(value)
-                            try:
-                                value = yaml.safe_load(value)
-                            except Exception:
-                                logger.exception('Exception when parsing dict %s', value)
-                                value = None
-                        if value:
-                            ret[name.lower()][suffix.lower()] = value
-                    # PATRONI_<username>_PASSWORD=<password>, PATRONI_<username>_OPTIONS=<option1,option2,...>
-                    # CREATE USER "<username>" WITH <OPTIONS> PASSWORD '<password>'
-                    elif suffix == 'PASSWORD':
-                        password = os.environ.pop(param)
-                        if password:
-                            users[name] = {'password': password}
-                            options = os.environ.pop(param[:-9] + '_OPTIONS', None)
-                            options = options and _parse_list(options)
-                            if options:
-                                users[name]['options'] = options
+                if suffix in ('HOST', 'HOSTS', 'PORT', 'USE_PROXIES', 'PROTOCOL', 'SRV', 'URL', 'PROXY',
+                              'CACERT', 'CERT', 'KEY', 'VERIFY', 'TOKEN', 'CHECKS', 'DC', 'REGISTER_SERVICE',
+                              'SERVICE_CHECK_INTERVAL', 'NAMESPACE', 'CONTEXT', 'USE_ENDPOINTS', 'SCOPE_LABEL',
+                              'ROLE_LABEL', 'POD_IP', 'PORTS', 'LABELS') and name:
+                    value = os.environ.pop(param)
+                    if suffix == 'PORT':
+                        value = value and parse_int(value)
+                    elif suffix in ('HOSTS', 'PORTS', 'CHECKS'):
+                        value = value and _parse_list(value)
+                    elif suffix == 'LABELS':
+                        value = _parse_dict(value)
+                    elif suffix in ('USE_PROXIES', 'REGISTER_SERVICE'):
+                        value = parse_bool(value)
+                    if value:
+                        ret[name.lower()][suffix.lower()] = value
+        if 'etcd' in ret:
+            ret['etcd'].update(_get_auth('etcd'))
+
+        users = {}
+        for param in list(os.environ.keys()):
+            if param.startswith(Config.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>'
+                if name and suffix == 'PASSWORD':
+                    password = os.environ.pop(param)
+                    if password:
+                        users[name] = {'password': password}
+                        options = os.environ.pop(param[:-9] + '_OPTIONS', None)
+                        options = options and _parse_list(options)
+                        if options:
+                            users[name]['options'] = options
         if users:
             ret['bootstrap']['users'] = users
 
@@ -317,8 +358,15 @@ class Config(object):
         if 'name' not in config and 'name' in pg_config:
             config['name'] = pg_config['name']
 
-        pg_config.update({p: config[p] for p in ('name', 'scope', 'retry_timeout',
-                          'synchronous_mode', 'maximum_lag_on_failover') if p in config})
+        updated_fields = (
+            'name',
+            'scope',
+            'retry_timeout',
+            'synchronous_mode',
+            'synchronous_mode_strict',
+        )
+
+        pg_config.update({p: config[p] for p in updated_fields if p in config})
 
         return config
 

patroni/ctl.py

@@ -63,8 +63,8 @@ def parse_dcs(dcs):
     elif scheme not in DCS_DEFAULTS:
         raise PatroniCtlException('Unknown dcs scheme: {}'.format(scheme))
 
-    dcs_info = DCS_DEFAULTS[scheme]
-    return yaml.load(dcs_info['template'].format(host=parsed.hostname or 'localhost', port=port or dcs_info['port']))
+    default = DCS_DEFAULTS[scheme]
+    return yaml.safe_load(default['template'].format(host=parsed.hostname or 'localhost', port=port or default['port']))
 
 
 def load_config(path, dcs):
@@ -103,15 +103,20 @@ option_watch = click.option('-W', is_flag=True, help='Auto update the screen eve
 option_force = click.option('--force', is_flag=True, help='Do not ask for confirmation at any point')
 arg_cluster_name = click.argument('cluster_name', required=False,
                                   default=lambda: click.get_current_context().obj.get('scope'))
+option_insecure = click.option('-k', '--insecure', is_flag=True, help='Allow connections to SSL sites without certs')
 
 
 @click.group()
 @click.option('--config-file', '-c', help='Configuration file', default=CONFIG_FILE_PATH)
 @click.option('--dcs', '-d', help='Use this DCS', envvar='DCS')
+@option_insecure
 @click.pass_context
-def ctl(ctx, config_file, dcs):
+def ctl(ctx, config_file, dcs, insecure):
     logging.basicConfig(format='%(asctime)s - %(levelname)s - %(message)s', level=os.environ.get('LOGLEVEL', 'WARNING'))
+    logging.captureWarnings(True)  # Capture eventual SSL warning
     ctx.obj = load_config(config_file, dcs)
+    # backward compatibility for configuration file where ctl section is not define
+    ctx.obj.setdefault('ctl', {})['insecure'] = ctx.obj.get('ctl', {}).get('insecure') or insecure
 
 
 def get_dcs(config, scope):
@@ -129,6 +134,7 @@ def auth_header(config):
 
 
 def request_patroni(member, request_type, endpoint, content=None, headers=None):
+    ctx = click.get_current_context()  # the current click context
     headers = headers or {}
     url_parts = urlparse(member.api_url)
     logging.debug(url_parts)
@@ -137,8 +143,21 @@ def request_patroni(member, request_type, endpoint, content=None, headers=None):
 
     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)
+                                           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'):
@@ -161,7 +180,7 @@ def print_output(columns, rows=None, alignment=None, fmt='pretty', header=True,
 
     if fmt == 'tsv':
         if columns is not None and header:
-            click.echo(delimiter.join(columns) + '\n')
+            click.echo(delimiter.join(columns))
 
         for r in rows:
             c = [str(c) for c in r]
@@ -233,7 +252,7 @@ def get_cursor(cluster, connect_parameters, role='master', member=None):
     if role == 'any':
         return cursor
 
-    cursor.execute('SELECT pg_is_in_recovery()')
+    cursor.execute('SELECT pg_catalog.pg_is_in_recovery()')
     in_recovery = cursor.fetchone()[0]
 
     if in_recovery and role == 'replica' or not in_recovery and role == 'master':
@@ -373,7 +392,7 @@ def query_member(cluster, cursor, member, role, command, connect_parameters):
             logging.debug(message)
             return [[timestamp(0), message]], None
 
-        cursor.execute('SELECT pg_is_in_recovery()')
+        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':
@@ -585,7 +604,8 @@ def _do_failover_or_switchover(obj, action, cluster_name, master, candidate, for
     if master is not None and cluster.leader and cluster.leader.member.name != master:
         raise PatroniCtlException('Member {0} is not the leader of cluster {1}'.format(master, cluster_name))
 
-    candidate_names = [str(m.name) for m in cluster.members if m.name != master]
+    # excluding members with nofailover tag
+    candidate_names = [str(m.name) for m in cluster.members if m.name != master and not m.nofailover]
     # We sort the names for consistent output to the client
     candidate_names.sort()
 
@@ -696,6 +716,10 @@ def output_members(cluster, name, extended=False, fmt='pretty'):
     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)
 
@@ -712,7 +736,11 @@ def output_members(cluster, name, extended=False, fmt='pretty'):
         elif xlog_location_cluster >= xlog_location:
             lag = round((xlog_location_cluster - xlog_location)/1024/1024)
 
-        row = [name, m.name, m.conn_kwargs()['host'], role, m.data.get('state', ''), lag]
+        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 '')
@@ -729,8 +757,8 @@ def output_members(cluster, name, extended=False, fmt='pretty'):
 
         rows.append(row)
 
-    columns = ['Cluster', 'Member', 'Host', 'Role', 'State', 'Lag in MB']
-    alignment = {'Lag in MB': 'r'}
+    columns = ['Cluster', 'Member', 'Host', 'Role', 'State', 'TL', 'Lag in MB']
+    alignment = {'Lag in MB': 'r', 'TL': 'r'}
 
     if extended or has_pending_restarts:
         columns.append('Pending restart')
@@ -902,7 +930,8 @@ def toggle_pause(config, cluster_name, paused, wait):
     for member in members:
         try:
             r = request_patroni(member, 'patch', 'config', {'pause': paused or None}, auth_header(config))
-        except Exception:
+        except Exception as err:
+            logging.warning(str(err))
             logging.warning('Member %s is not accessible', member.name)
             continue
 

patroni/dcs/__init__.py

@@ -6,19 +6,39 @@ import json
 import logging
 import os
 import pkgutil
+import re
 import six
 import sys
+import time
 
-from collections import namedtuple
+from collections import defaultdict, namedtuple
+from copy import deepcopy
 from patroni.exceptions import PatroniException
 from patroni.utils import parse_bool
 from random import randint
 from six.moves.urllib_parse import urlparse, urlunparse, parse_qsl
 from threading import Event, Lock
 
+slot_name_re = re.compile('^[a-z0-9_]{1,63}$')
 logger = logging.getLogger(__name__)
 
 
+def slot_name_from_member_name(member_name):
+    """Translate member name to valid PostgreSQL slot name.
+
+    PostgreSQL replication slot names must be valid PostgreSQL names. This function maps the wider space of
+    member names to valid PostgreSQL names. Names are lowercased, dashes and periods common in hostnames
+    are replaced with underscores, other characters are encoded as their unicode codepoint. Name is truncated
+    to 64 characters. Multiple different member names may map to a single slot name."""
+
+    def replace_char(match):
+        c = match.group(0)
+        return '_' if c in '-.' else "u{:04d}".format(ord(c))
+
+    slot_name = re.sub('[^a-z0-9_]', replace_char, member_name.lower())
+    return slot_name[0:63]
+
+
 def parse_connection_string(value):
     """Original Governor stores connection strings for each cluster members if a following format:
         postgres://{username}:{password}@{connect_address}/postgres
@@ -108,12 +128,29 @@ class Member(namedtuple('Member', 'index,name,session,data')):
 
     @property
     def conn_url(self):
-        return self.data.get('conn_url')
+        conn_url = self.data.get('conn_url')
+        conn_kwargs = self.data.get('conn_kwargs')
+        if conn_url:
+            return conn_url
+
+        if conn_kwargs:
+            conn_url = 'postgresql://{host}:{port}'.format(
+                host=conn_kwargs.get('host'),
+                port=conn_kwargs.get('port'),
+            )
+            self.data['conn_url'] = conn_url
+            return conn_url
 
     def conn_kwargs(self, auth=None):
+        defaults = {
+            "host": "",
+            "port": "",
+            "database": ""
+        }
         ret = self.data.get('conn_kwargs')
         if ret:
-            ret = ret.copy()
+            defaults.update(ret)
+            ret = defaults
         else:
             r = urlparse(self.conn_url)
             ret = {
@@ -159,6 +196,26 @@ class Member(namedtuple('Member', 'index,name,session,data')):
         return self.state == 'running'
 
 
+class RemoteMember(Member):
+    """ Represents a remote master for a standby cluster
+    """
+    def __new__(cls, name, data):
+        return super(RemoteMember, cls).__new__(cls, None, name, None, data)
+
+    @staticmethod
+    def allowed_keys():
+        return ('primary_slot_name',
+                'create_replica_methods',
+                'restore_command',
+                'archive_cleanup_command',
+                'recovery_min_apply_delay',
+                'no_replication_slot')
+
+    def __getattr__(self, name):
+        if name in RemoteMember.allowed_keys():
+            return self.data.get(name)
+
+
 class Leader(namedtuple('Leader', 'index,session,member')):
 
     """Immutable object (namedtuple) which represents leader key.
@@ -236,14 +293,24 @@ class ClusterConfig(namedtuple('ClusterConfig', 'index,data,modify_index')):
     def from_node(index, data, modify_index=None):
         """
         >>> ClusterConfig.from_node(1, '{') is None
-        True
+        False
         """
 
         try:
             data = json.loads(data)
         except (TypeError, ValueError):
-            return None
-        return ClusterConfig(index, data, modify_index or index)
+            data = None
+            modify_index = 0
+        if not isinstance(data, dict):
+            data = {}
+        return ClusterConfig(index, data, index if modify_index is None else modify_index)
+
+    @property
+    def permanent_slots(self):
+        return isinstance(self.data, dict) and (
+                self.data.get('permanent_replication_slots') or
+                self.data.get('permanent_slots') or self.data.get('slots')
+        ) or {}
 
 
 class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
@@ -302,7 +369,7 @@ class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
         return name is not None and name in (self.leader, self.sync_standby)
 
 
-class TimelineHistory(namedtuple('TimelineHistory', 'index,lines')):
+class TimelineHistory(namedtuple('TimelineHistory', 'index,value,lines')):
     """Object representing timeline history file"""
 
     @staticmethod
@@ -318,7 +385,7 @@ class TimelineHistory(namedtuple('TimelineHistory', 'index,lines')):
             lines = None
         if not isinstance(lines, list):
             lines = []
-        return TimelineHistory(index, lines)
+        return TimelineHistory(index, value, lines)
 
 
 class Cluster(namedtuple('Cluster', 'initialize,config,leader,last_leader_operation,members,failover,sync,history')):
@@ -359,6 +426,85 @@ 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):
+        # 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
+        if role in ('master', 'standby_leader'):
+            slot_members = [m.name for m in self.members if m.name != name and
+                            (m.replicatefrom is None or m.replicatefrom == 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]
+            permanent_slots = {}
+
+        slots = {slot_name_from_member_name(name): {'type': 'physical'} for name in slot_members}
+
+        if len(slots) < len(slot_members):
+            # Find which names are conflicting for a nicer error message
+            slot_conflicts = defaultdict(list)
+            for name in slot_members:
+                slot_conflicts[slot_name_from_member_name(name)].append(name)
+            logger.error("Following cluster members share a replication slot name: %s",
+                         "; ".join("{} map to {}".format(", ".join(v), k)
+                                   for k, v in slot_conflicts.items() if len(v) > 1))
+
+        # "merge" replication slots for members with permanent_replication_slots
+        for name, value in permanent_slots.items():
+            if not slot_name_re.match(name):
+                logger.error("Invalid permanent replication slot name '%s'", name)
+                logger.error("Slot name may only contain lower case letters, numbers, and the underscore chars")
+                continue
+
+            if name in slots:
+                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' \
+                        and value.get('database') and value.get('plugin'):
+                    slots[name] = value
+                    continue
+
+            logger.error("Bad value for slot '%s' in permanent_slots: %s", name, permanent_slots[name])
+
+        return slots
+
+    def has_permanent_logical_slots(self, name):
+        slots = self.get_replication_slots(name, 'master').values()
+        return any(v for v in slots if v.get("type") == "logical")
+
+    @property
+    def timeline(self):
+        """
+        >>> Cluster(0, 0, 0, 0, 0, 0, 0, 0).timeline
+        0
+        >>> Cluster(0, 0, 0, 0, 0, 0, 0, TimelineHistory.from_node(1, '[]')).timeline
+        1
+        >>> Cluster(0, 0, 0, 0, 0, 0, 0, TimelineHistory.from_node(1, '[["a"]]')).timeline
+        0
+        """
+        if self.history:
+            if self.history.lines:
+                try:
+                    return int(self.history.lines[-1][0]) + 1
+                except Exception:
+                    logger.error('Failed to parse cluster history from DCS: %s', self.history.lines)
+            elif self.history.value == '[]':
+                return 1
+        return 0
+
 
 @six.add_metaclass(abc.ABCMeta)
 class AbstractDCS(object):
@@ -379,11 +525,12 @@ class AbstractDCS(object):
             i.e.: `zookeeper` for zookeeper, `etcd` for etcd, etc...
         """
         self._name = config['name']
-        self._base_path = os.path.join('/', config.get('namespace', '/service/').strip('/'), config['scope'])
+        self._base_path = re.sub('/+', '/', '/'.join(['', config.get('namespace', 'service'), config['scope']]))
         self._set_loop_wait(config.get('loop_wait', 10))
 
         self._ctl = bool(config.get('patronictl', False))
         self._cluster = None
+        self._cluster_valid_till = 0
         self._cluster_thread_lock = Lock()
         self._last_leader_operation = ''
         self.event = Event()
@@ -431,6 +578,10 @@ class AbstractDCS(object):
     def set_ttl(self, ttl):
         """Set the new ttl value for leader key"""
 
+    @abc.abstractmethod
+    def ttl(self):
+        """Get new ttl value"""
+
     @abc.abstractmethod
     def set_retry_timeout(self, retry_timeout):
         """Set the new value for retry_timeout"""
@@ -458,22 +609,26 @@ class AbstractDCS(object):
            instance would be demoted."""
 
     def get_cluster(self):
+        try:
+            cluster = self._load_cluster()
+        except Exception:
+            self.reset_cluster()
+            raise
+
         with self._cluster_thread_lock:
-            try:
-                self._load_cluster()
-            except Exception:
-                self._cluster = None
-                raise
-            return self._cluster
+            self._cluster = cluster
+            self._cluster_valid_till = time.time() + self.ttl
+            return cluster
 
     @property
     def cluster(self):
         with self._cluster_thread_lock:
-            return self._cluster
+            return self._cluster if self._cluster_valid_till > time.time() else None
 
     def reset_cluster(self):
         with self._cluster_thread_lock:
             self._cluster = None
+            self._cluster_valid_till = 0
 
     @abc.abstractmethod
     def _write_leader_optime(self, last_operation):
@@ -495,7 +650,7 @@ class AbstractDCS(object):
         You have to use CAS (Compare And Swap) operation in order to update leader key,
         for example for etcd `prevValue` parameter must be used."""
 
-    def update_leader(self, last_operation):
+    def update_leader(self, last_operation, access_is_restricted=False):
         """Update leader key (or session) ttl and optime/leader
 
         :param last_operation: absolute xlog location in bytes
@@ -539,7 +694,7 @@ class AbstractDCS(object):
         """Create or update `/config` key"""
 
     @abc.abstractmethod
-    def touch_member(self, data, ttl=None, permanent=False):
+    def touch_member(self, data, permanent=False):
         """Update member key in DCS.
         This method should create or update key with the name = '/members/' + `~self._name`
         and value = data in a given DCS.

patroni/dcs/consul.py

@@ -2,6 +2,7 @@ from __future__ import absolute_import
 import json
 import logging
 import os
+import re
 import socket
 import ssl
 import time
@@ -12,7 +13,7 @@ from patroni.dcs import AbstractDCS, ClusterConfig, Cluster, Failover, Leader, M
 from patroni.exceptions import DCSError
 from patroni.utils import deep_compare, parse_bool, Retry, RetryFailedError, split_host_port
 from urllib3.exceptions import HTTPError
-from six.moves.urllib.parse import urlencode, urlparse
+from six.moves.urllib.parse import urlencode, urlparse, quote
 from six.moves.http_client import HTTPException
 
 logger = logging.getLogger(__name__)
@@ -26,10 +27,14 @@ class ConsulInternalError(ConsulException):
     """An internal Consul server error occurred"""
 
 
-class InvalidSessionTTL(ConsulInternalError):
+class InvalidSessionTTL(ConsulException):
     """Session TTL is too small or too big"""
 
 
+class InvalidSession(ConsulException):
+    """invalid session"""
+
+
 class HTTPClient(object):
 
     def __init__(self, host='127.0.0.1', port=8500, token=None, scheme='http', verify=True, cert=None, ca_cert=None):
@@ -71,6 +76,8 @@ class HTTPClient(object):
             msg = '{0} {1}'.format(response.status, data)
             if data.startswith('Invalid Session TTL'):
                 raise InvalidSessionTTL(msg)
+            elif data.startswith('invalid session'):
+                raise InvalidSession(msg)
             else:
                 raise ConsulInternalError(msg)
         return base.Response(response.status, response.headers, data)
@@ -95,7 +102,12 @@ class HTTPClient(object):
                 params = {k: v for k, v in params}
             kwargs = {'retries': 0, 'preload_content': False, 'body': data}
             if method == 'get' and isinstance(params, dict) and 'index' in params:
-                kwargs['timeout'] = (float(params['wait'][:-1]) if 'wait' in params else 300) + 1
+                timeout = float(params['wait'][:-1]) if 'wait' in params else 300
+                # According to the documentation a small random amount of additional wait time is added to the
+                # supplied maximum wait time to spread out the wake up time of any concurrent requests. This adds
+                # up to wait / 16 additional time to the maximum duration. Since our goal is actually getting a
+                # response rather read timeout we will add to the timeout a sligtly bigger value.
+                kwargs['timeout'] = timeout + max(timeout/15.0, 1)
             else:
                 kwargs['timeout'] = self._read_timeout
             token = params.pop('token', self.token) if isinstance(params, dict) else self.token
@@ -133,6 +145,31 @@ def catch_consul_errors(func):
     return wrapper
 
 
+def force_if_last_failed(func):
+    def wrapper(*args, **kwargs):
+        if wrapper.last_result is False:
+            kwargs['force'] = True
+        wrapper.last_result = func(*args, **kwargs)
+        return wrapper.last_result
+
+    wrapper.last_result = None
+    return wrapper
+
+
+def service_name_from_scope_name(scope_name):
+    """Translate scope name to service name which can be used in dns.
+
+    230 = 253 - len('replica.') - len('.service.consul')
+    """
+
+    def replace_char(match):
+        c = match.group(0)
+        return '-' if c in '. _' else "u{:04d}".format(ord(c))
+
+    service_name = re.sub(r'[^a-z0-9\-]', replace_char, scope_name.lower())
+    return service_name[0:230]
+
+
 class Consul(AbstractDCS):
 
     def __init__(self, config):
@@ -144,7 +181,6 @@ class Consul(AbstractDCS):
                             retry_exceptions=(ConsulInternalError, HTTPException,
                                               HTTPError, socket.error, socket.timeout))
 
-        self._my_member_data = {}
         kwargs = {}
         if 'url' in config:
             r = urlparse(config['url'])
@@ -175,6 +211,13 @@ class Consul(AbstractDCS):
         self.set_ttl(config.get('ttl') or 30)
         self._last_session_refresh = 0
         self.__session_checks = config.get('checks')
+        self._register_service = config.get('register_service', False)
+        if self._register_service:
+            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,
+                               self._scope)
+        self._service_check_interval = config.get('service_check_interval', '5s')
         if not self._ctl:
             self.create_session()
 
@@ -194,6 +237,10 @@ class Consul(AbstractDCS):
             self._session = None
             self.__do_not_watch = True
 
+    @property
+    def ttl(self):
+        return self._client.http.ttl
+
     def set_retry_timeout(self, retry_timeout):
         self._retry.deadline = retry_timeout
         self._client.http.set_read_timeout(retry_timeout)
@@ -256,7 +303,7 @@ class Consul(AbstractDCS):
             nodes = {}
             for node in results:
                 node['Value'] = (node['Value'] or b'').decode('utf-8')
-                nodes[os.path.relpath(node['Key'], path)] = node
+                nodes[node['Key'][len(path):].lstrip('/')] = node
 
             # get initialize flag
             initialize = nodes.get(self._INITIALIZE)
@@ -299,48 +346,111 @@ class Consul(AbstractDCS):
             sync = nodes.get(self._SYNC)
             sync = SyncState.from_node(sync and sync['ModifyIndex'], sync and sync['Value'])
 
-            self._cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+            return Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
         except NotFound:
-            self._cluster = Cluster(None, None, None, None, [], None, None, None)
+            return Cluster(None, None, None, None, [], None, None, None)
         except Exception:
             logger.exception('get_cluster')
             raise ConsulError('Consul is not responding properly')
 
-    def touch_member(self, data, ttl=None, permanent=False):
+    @catch_consul_errors
+    def touch_member(self, data, permanent=False):
         cluster = self.cluster
         member = cluster and cluster.get_member(self._name, fallback_to_leader=False)
         create_member = not permanent and self.refresh_session()
 
         if member and (create_member or member.session != self._session):
-            try:
-                self._client.kv.delete(self.member_path)
-                create_member = True
-            except Exception:
-                return False
+            self._client.kv.delete(self.member_path)
+            create_member = True
 
-        if not create_member and member and deep_compare(data, self._my_member_data):
+        if not create_member and member and deep_compare(data, member.data):
             return True
 
         try:
             args = {} if permanent else {'acquire': self._session}
             self._client.kv.put(self.member_path, json.dumps(data, separators=(',', ':')), **args)
-            self._my_member_data = data
+            if self._register_service:
+                self.update_service(not create_member and member and member.data or {}, data)
             return True
+        except InvalidSession:
+            self._session = None
+            logger.error('Our session disappeared from Consul, can not "touch_member"')
         except Exception:
             logger.exception('touch_member')
         return False
 
     @catch_consul_errors
-    def _do_attempt_to_acquire_leader(self, kwargs):
-        return self.retry(self._client.kv.put, self.leader_path, self._name, **kwargs)
+    def register_service(self, service_name, **kwargs):
+        logger.info('Register service %s, params %s', service_name, kwargs)
+        return self._client.agent.service.register(service_name, **kwargs)
+
+    @catch_consul_errors
+    def deregister_service(self, service_id):
+        logger.info('Deregister service %s', service_id)
+        # service_id can contain special characters, but is used as part of uri in deregister request
+        service_id = quote(service_id)
+        return self._client.agent.service.deregister(service_id)
+
+    def _update_service(self, data):
+        service_name = self._service_name
+        role = data['role'].replace('_', '-')
+        state = data['state']
+        api_parts = urlparse(data['api_url'])
+        api_parts = api_parts._replace(path='/{0}'.format(role))
+        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))
+        params = {
+            'service_id': '{0}/{1}'.format(self._scope, self._name),
+            'address': conn_parts.hostname,
+            'port': conn_parts.port,
+            'check': check,
+            'tags': [role]
+        }
+
+        if state == 'stopped':
+            return self.deregister_service(params['service_id'])
+
+        if role in ['master', 'replica', 'standby-leader']:
+            if state != 'running':
+                return
+            return self.register_service(service_name, **params)
+
+        logger.warning('Could not register service: unknown role type %s', role)
+
+    @force_if_last_failed
+    def update_service(self, old_data, new_data, force=False):
+        update = False
+
+        for key in ['role', 'api_url', 'conn_url', 'state']:
+            if key not in new_data:
+                logger.warning('Could not register service: not enough params in member data')
+                return
+            if old_data.get(key) != new_data[key]:
+                update = True
+
+        if force or update:
+            return self._update_service(new_data)
+
+    @catch_consul_errors
+    def _do_attempt_to_acquire_leader(self, permanent):
+        try:
+            kwargs = {} if permanent else {'acquire': self._session}
+            return self.retry(self._client.kv.put, self.leader_path, self._name, **kwargs)
+        except InvalidSession:
+            self._session = None
+            logger.error('Our session disappeared from Consul. Will try to get a new one and retry attempt')
+            self.refresh_session()
+            return self.retry(self._client.kv.put, self.leader_path, self._name, acquire=self._session)
 
     def attempt_to_acquire_leader(self, permanent=False):
         if not self._session and not permanent:
             self.refresh_session()
 
-        ret = self._do_attempt_to_acquire_leader({} if permanent else {'acquire': self._session})
+        ret = self._do_attempt_to_acquire_leader(permanent)
         if not ret:
             logger.info('Could not take out TTL lock')
+
         return ret
 
     def take_leader(self):
@@ -397,6 +507,7 @@ class Consul(AbstractDCS):
         return self.retry(self._client.kv.delete, self.sync_path, cas=index)
 
     def watch(self, leader_index, timeout):
+        self._last_session_refresh = 0
         if self.__do_not_watch:
             self.__do_not_watch = False
             return True
@@ -408,7 +519,7 @@ class Consul(AbstractDCS):
                     idx, _ = self._client.kv.get(self.leader_path, index=leader_index, wait=str(timeout) + 's')
                     return str(idx) != str(leader_index)
                 except (ConsulException, HTTPException, HTTPError, socket.error, socket.timeout):
-                    logging.exception('watch')
+                    logger.exception('watch')
 
                 timeout = end_time - time.time()
 

patroni/dcs/etcd.py

@@ -87,9 +87,12 @@ class Client(etcd.Client):
         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)
+        # 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._load_machines_cache()
-        self._allow_reconnect = not self._use_proxies
+        self._allow_reconnect = True
 
     def _build_request_parameters(self):
         kwargs = {'headers': self._get_headers(), 'redirect': self.allow_redirect}
@@ -128,8 +131,11 @@ class Client(etcd.Client):
         while True:
             try:
                 response = self.http.request(self._MGET, self._base_uri + self.version_prefix + '/machines', **kwargs)
-                machines = [n.strip() for n in self._handle_server_response(response).data.decode('utf-8').split(',')]
+                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:
+                    raise etcd.EtcdException
                 random.shuffle(machines)
                 for url in machines:
                     r = urlparse(url)
@@ -186,10 +192,8 @@ class Client(etcd.Client):
         # Update machines_cache if previous attempt of update has failed
         if self._update_machines_cache:
             self._load_machines_cache()
-        elif time.time() - self._machines_cache_updated > self._machines_cache_ttl:
-            self._machines_cache = self.machines
-            if self._base_uri in self._machines_cache:
-                self._machines_cache.remove(self._base_uri)
+        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())
@@ -206,10 +210,8 @@ class Client(etcd.Client):
 
                 if response is False:
                     some_request_failed = True
-            if some_request_failed and not self._use_proxies:
-                self._machines_cache = self.machines
-                if self._base_uri in self._machines_cache:
-                    self._machines_cache.remove(self._base_uri)
+            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()
@@ -268,6 +270,21 @@ class Client(etcd.Client):
                 return list(set(ret))
         return [uri(self.protocol, host, port)]
 
+    def _get_machines_cache_from_config(self):
+        if 'proxy' in self._config:
+            return [uri(self.protocol, self._config['host'], self._config['port'])]
+
+        machines_cache = []
+        if 'srv' in self._config:
+            machines_cache = self._get_machines_cache_from_srv(self._config['srv'])
+
+        if not machines_cache and 'hosts' in self._config:
+            machines_cache = list(self._config['hosts'])
+
+        if not machines_cache and 'host' in self._config:
+            machines_cache = self._get_machines_cache_from_dns(self._config['host'], self._config['port'])
+        return machines_cache
+
     def _load_machines_cache(self):
         """This method should fill up `_machines_cache` from scratch.
         It could happen only in two cases:
@@ -279,19 +296,7 @@ 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')
 
-        if self._use_proxies:
-            self._machines_cache = [uri(self.protocol, self._config['host'], self._config['port'])]
-        else:
-            self._machines_cache = []
-
-            if 'srv' in self._config:
-                self._machines_cache = self._get_machines_cache_from_srv(self._config['srv'])
-
-            if not self._machines_cache and 'hosts' in self._config:
-                self._machines_cache = list(self._config['hosts'])
-
-            if not self._machines_cache and 'host' in self._config:
-                self._machines_cache = self._get_machines_cache_from_dns(self._config['host'], self._config['port'])
+        self._machines_cache = self._get_machines_cache_from_config()
 
         # Can not bootstrap list of etcd-cluster members, giving up
         if not self._machines_cache:
@@ -299,14 +304,16 @@ class Client(etcd.Client):
 
         # After filling up initial list of machines_cache we should ask etcd-cluster about actual list
         self._base_uri = self._next_server()
-        self._machines_cache = self.machines
-
-        if self._base_uri in self._machines_cache:
-            self._machines_cache.remove(self._base_uri)
+        self._refresh_machines_cache()
 
         self._update_machines_cache = False
         self._machines_cache_updated = time.time()
 
+    def _refresh_machines_cache(self):
+        self._machines_cache = self._get_machines_cache_from_config() if self._use_proxies else self.machines
+        if self._base_uri in self._machines_cache:
+            self._machines_cache.remove(self._base_uri)
+
 
 class Etcd(AbstractDCS):
 
@@ -426,6 +433,8 @@ class Etcd(AbstractDCS):
         while not client:
             try:
                 client = Client(config, dns_resolver)
+                if 'use_proxies' in config and not client.machines:
+                    raise etcd.EtcdException
             except etcd.EtcdException:
                 logger.info('waiting on etcd')
                 time.sleep(5)
@@ -437,6 +446,10 @@ class Etcd(AbstractDCS):
         self._ttl = ttl
         self._client.set_machines_cache_ttl(ttl*10)
 
+    @property
+    def ttl(self):
+        return self._ttl
+
     def set_retry_timeout(self, retry_timeout):
         self._retry.deadline = retry_timeout
         self._client.set_read_timeout(retry_timeout)
@@ -446,9 +459,10 @@ class Etcd(AbstractDCS):
         return Member.from_node(node.modifiedIndex, os.path.basename(node.key), node.ttl, node.value)
 
     def _load_cluster(self):
+        cluster = None
         try:
             result = self.retry(self._client.read, self.client_path(''), recursive=True)
-            nodes = {os.path.relpath(node.key, result.key): node for node in result.leaves}
+            nodes = {node.key[len(result.key):].lstrip('/'): node for node in result.leaves}
 
             # get initialize flag
             initialize = nodes.get(self._INITIALIZE)
@@ -486,17 +500,18 @@ class Etcd(AbstractDCS):
             sync = nodes.get(self._SYNC)
             sync = SyncState.from_node(sync and sync.modifiedIndex, sync and sync.value)
 
-            self._cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+            cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
         except etcd.EtcdKeyNotFound:
-            self._cluster = Cluster(None, None, None, None, [], None, None, None)
+            cluster = Cluster(None, None, None, None, [], None, None, None)
         except Exception as e:
             self._handle_exception(e, 'get_cluster', raise_ex=EtcdError('Etcd is not responding properly'))
         self._has_failed = False
+        return cluster
 
     @catch_etcd_errors
-    def touch_member(self, data, ttl=None, permanent=False):
+    def touch_member(self, data, permanent=False):
         data = json.dumps(data, separators=(',', ':'))
-        return self.retry(self._client.set, self.member_path, data, None if permanent else ttl or self._ttl)
+        return self._client.set(self.member_path, data, None if permanent else self._ttl)
 
     @catch_etcd_errors
     def take_leader(self):

patroni/dcs/kubernetes.py

@@ -92,13 +92,14 @@ class Kubernetes(AbstractDCS):
         self.__subsets = None
         use_endpoints = config.get('use_endpoints') and (config.get('patronictl') or 'pod_ip' in config)
         if use_endpoints:
-            addresses = [k8s_client.V1EndpointAddress(ip=config['pod_ip'])]
+            addresses = [k8s_client.V1EndpointAddress(ip='127.0.0.1' if config.get('patronictl') else config['pod_ip'])]
             ports = []
             for p in config.get('ports', [{}]):
                 port = {'port': int(p.get('port', '5432'))}
                 port.update({n: p[n] for n in ('name', 'protocol') if p.get(n)})
                 ports.append(k8s_client.V1EndpointPort(**port))
             self.__subsets = [k8s_client.V1EndpointSubset(addresses=addresses, ports=ports)]
+            self._should_create_config_service = True
         self._api = CoreV1ApiProxy(use_endpoints)
         self.set_retry_timeout(config['retry_timeout'])
         self.set_ttl(config.get('ttl') or 30)
@@ -106,6 +107,7 @@ class Kubernetes(AbstractDCS):
         self._leader_observed_time = None
         self._leader_resource_version = None
         self._leader_observed_subsets = []
+        self._config_resource_version = None
         self.__do_not_watch = False
 
     def retry(self, *args, **kwargs):
@@ -123,6 +125,10 @@ class Kubernetes(AbstractDCS):
         self.__do_not_watch = self._ttl != ttl
         self._ttl = ttl
 
+    @property
+    def ttl(self):
+        return self._ttl
+
     def set_retry_timeout(self, retry_timeout):
         self._retry.deadline = retry_timeout
         self._api.set_timeout(retry_timeout)
@@ -145,6 +151,7 @@ class Kubernetes(AbstractDCS):
 
             config = nodes.get(self.config_path)
             metadata = config and config.metadata
+            self._config_resource_version = metadata.resource_version if metadata else None
             annotations = metadata and metadata.annotations or {}
 
             # get initialize flag
@@ -152,7 +159,8 @@ class Kubernetes(AbstractDCS):
 
             # get global dynamic configuration
             config = ClusterConfig.from_node(metadata and metadata.resource_version,
-                                             annotations.get(self._CONFIG) or '{}')
+                                             annotations.get(self._CONFIG) or '{}',
+                                             metadata.resource_version if self._CONFIG in annotations else 0)
 
             # get timeline history
             history = TimelineHistory.from_node(metadata and metadata.resource_version,
@@ -199,7 +207,7 @@ class Kubernetes(AbstractDCS):
             metadata = sync and sync.metadata
             sync = SyncState.from_node(metadata and metadata.resource_version,  metadata and metadata.annotations)
 
-            self._cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+            return Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
         except Exception:
             logger.exception('get_cluster')
             raise KubernetesError('Kubernetes API is not responding properly')
@@ -273,13 +281,34 @@ class Kubernetes(AbstractDCS):
             body = k8s_client.V1ConfigMap(metadata=metadata)
         return self.retry(func, self._namespace, body) if retry else func(self._namespace, body)
 
+    def patch_or_create_config(self, annotations, resource_version=None, patch=False, retry=True):
+        # SCOPE-config endpoint requires corresponding service otherwise it might be "cleaned" by k8s master
+        if self.__subsets and not patch and not resource_version:
+            self._should_create_config_service = True
+            self._create_config_service()
+        ret = self.patch_or_create(self.config_path, annotations, resource_version, patch, retry)
+        if ret:
+            self._config_resource_version = ret.metadata.resource_version
+        return ret
+
+    def _create_config_service(self):
+        metadata = k8s_client.V1ObjectMeta(namespace=self._namespace, name=self.config_path, labels=self._labels)
+        body = k8s_client.V1Service(metadata=metadata, spec=k8s_client.V1ServiceSpec(cluster_ip='None'))
+        try:
+            if not self._api.create_namespaced_service(self._namespace, body):
+                return
+        except Exception as e:
+            if not isinstance(e, k8s_client.rest.ApiException) or e.status != 409:  # Service already exists
+                return logger.exception('create_config_service failed')
+        self._should_create_config_service = False
+
     def _write_leader_optime(self, last_operation):
         """Unused"""
 
     def _update_leader(self):
         """Unused"""
 
-    def update_leader(self, last_operation):
+    def update_leader(self, last_operation, access_is_restricted=False):
         now = datetime.datetime.now(tzutc).isoformat()
         annotations = {self._LEADER: self._name, 'ttl': str(self._ttl), 'renewTime': now,
                        'acquireTime': self._leader_observed_record.get('acquireTime') or now,
@@ -287,7 +316,9 @@ class Kubernetes(AbstractDCS):
         if last_operation:
             annotations[self._OPTIME] = last_operation
 
-        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=self.__subsets)
+        subsets = [] if access_is_restricted else self.__subsets
+
+        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=subsets)
         if ret:
             self._leader_resource_version = ret.metadata.resource_version
         return ret
@@ -307,7 +338,8 @@ class Kubernetes(AbstractDCS):
             else:
                 annotations['acquireTime'] = self._leader_observed_record.get('acquireTime') or now
             annotations['transitions'] = str(transitions)
-        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=self.__subsets)
+        subsets = [] if self.__subsets else None
+        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=subsets)
         if ret:
             self._leader_resource_version = ret.metadata.resource_version
         else:
@@ -326,14 +358,13 @@ class Kubernetes(AbstractDCS):
         return self.patch_or_create(self.failover_path, annotations, index, bool(index or patch), False)
 
     def set_config_value(self, value, index=None):
-        patch = bool(index or self.cluster and self.cluster.config and self.cluster.config.index)
-        return self.patch_or_create(self.config_path, {self._CONFIG: value}, index, patch, False)
+        return self.patch_or_create_config({self._CONFIG: value}, index, bool(self._config_resource_version), False)
 
     @catch_kubernetes_errors
-    def touch_member(self, data, ttl=None, permanent=False):
+    def touch_member(self, data, permanent=False):
         cluster = self.cluster
         if cluster and cluster.leader and cluster.leader.name == self._name:
-            role = 'master'
+            role = 'promoted' if data['role'] in ('replica', 'promoted') else 'master'
         elif data['state'] == 'running' and data['role'] != 'master':
             role = data['role']
         else:
@@ -348,12 +379,14 @@ class Kubernetes(AbstractDCS):
                         'annotations': {'status': json.dumps(data, separators=(',', ':'))}}
             body = k8s_client.V1Pod(metadata=k8s_client.V1ObjectMeta(**metadata))
             ret = self._api.patch_namespaced_pod(self._name, self._namespace, body)
+        if self.__subsets and self._should_create_config_service:
+            self._create_config_service()
         return ret
 
     def initialize(self, create_new=True, sysid=""):
         cluster = self.cluster
         resource_version = cluster.config.index if cluster and cluster.config and cluster.config.index else None
-        return self.patch_or_create(self.config_path, {self._INITIALIZE: sysid}, resource_version)
+        return self.patch_or_create_config({self._INITIALIZE: sysid}, resource_version)
 
     def delete_leader(self):
         if self.cluster and isinstance(self.cluster.leader, Leader) and self.cluster.leader.name == self._name:
@@ -361,15 +394,14 @@ class Kubernetes(AbstractDCS):
             self.reset_cluster()
 
     def cancel_initialization(self):
-        self.patch_or_create(self.config_path, {self._INITIALIZE: None}, self.cluster.config.index, True)
+        self.patch_or_create_config({self._INITIALIZE: None}, self._config_resource_version, True)
 
     @catch_kubernetes_errors
     def delete_cluster(self):
         self.retry(self._api.delete_collection_namespaced_kind, self._namespace, label_selector=self._label_selector)
 
     def set_history_value(self, value):
-        patch = bool(self.cluster and self.cluster.config and self.cluster.config.index)
-        return self.patch_or_create(self.config_path, {self._HISTORY: value}, None, patch, False)
+        return self.patch_or_create_config({self._HISTORY: value}, None, bool(self._config_resource_version), False)
 
     def set_sync_state_value(self, value, index=None):
         """Unused"""
@@ -399,7 +431,7 @@ class Kubernetes(AbstractDCS):
                 except KeyboardInterrupt:
                     raise
                 except Exception:
-                    logging.exception('watch')
+                    logger.exception('watch')
 
                 timeout = end_time - time.time()
 

patroni/dcs/zookeeper.py

@@ -1,5 +1,6 @@
 import json
 import logging
+import select
 import time
 
 from kazoo.client import KazooClient, KazooState, KazooRetry
@@ -37,12 +38,21 @@ class PatroniSequentialThreadingHandler(SequentialThreadingHandler):
                      `connect_timeout` (negotiated session timeout) as the second element."""
 
         args = list(args)
-        if len(args) == 1:
+        if len(args) == 0:  # kazoo 2.6.0 slightly changed the way how it calls create_connection method
+            kwargs['timeout'] = max(self._connect_timeout, kwargs.get('timeout', self._connect_timeout*10)/10.0)
+        elif len(args) == 1:
             args.append(self._connect_timeout)
         else:
             args[1] = max(self._connect_timeout, args[1]/10.0)
         return super(PatroniSequentialThreadingHandler, self).create_connection(*args, **kwargs)
 
+    def select(self, *args, **kwargs):
+        """Python3 raises `ValueError` if socket is closed, because fd == -1"""
+        try:
+            return super(PatroniSequentialThreadingHandler, self).select(*args, **kwargs)
+        except ValueError as e:
+            raise select.error(9, str(e))
+
 
 class ZooKeeper(AbstractDCS):
 
@@ -59,7 +69,6 @@ class ZooKeeper(AbstractDCS):
                                    max_delay=1, max_tries=-1, sleep_func=time.sleep))
         self._client.add_listener(self.session_listener)
 
-        self._my_member_data = {}
         self._fetch_cluster = True
 
         self._orig_kazoo_connect = self._client._connection._connect
@@ -117,6 +126,10 @@ class ZooKeeper(AbstractDCS):
             self._client.restart()
             return True
 
+    @property
+    def ttl(self):
+        return self._client._session_timeout
+
     def set_retry_timeout(self, retry_timeout):
         retry = self._client.retry if isinstance(self._client.retry, KazooRetry) else self._client._retry
         retry.deadline = retry_timeout
@@ -197,58 +210,67 @@ class ZooKeeper(AbstractDCS):
         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])
 
-        self._cluster = Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
+        return Cluster(initialize, config, leader, last_leader_operation, members, failover, sync, history)
 
     def _load_cluster(self):
-        if self._fetch_cluster or self._cluster is None:
+        cluster = self.cluster
+        if self._fetch_cluster or cluster is None:
             try:
-                self._client.retry(self._inner_load_cluster)
+                cluster = self._client.retry(self._inner_load_cluster)
             except Exception:
                 logger.exception('get_cluster')
                 self.cluster_watcher(None)
                 raise ZooKeeperError('ZooKeeper in not responding properly')
+        return cluster
 
-    def _create(self, path, value, **kwargs):
+    def _create(self, path, value, retry=False, ephemeral=False):
         try:
-            self._client.retry(self._client.create, path, value.encode('utf-8'), **kwargs)
+            if retry:
+                self._client.retry(self._client.create, path, value, makepath=True, ephemeral=ephemeral)
+            else:
+                self._client.create_async(path, value, makepath=True, ephemeral=ephemeral).get(timeout=1)
             return True
         except Exception:
-            return False
+            logger.exception('Failed to create %s', path)
+        return False
 
     def attempt_to_acquire_leader(self, permanent=False):
-        ret = self._create(self.leader_path, self._name, makepath=True, ephemeral=not permanent)
+        ret = self._create(self.leader_path, self._name.encode('utf-8'), retry=True, ephemeral=not permanent)
         if not ret:
             logger.info('Could not take out TTL lock')
         return ret
 
-    def __set_failover_or_sync_state_value(self, key, value, index=None):
+    def _set_or_create(self, key, value, index=None, retry=False, do_not_create_empty=False):
+        value = value.encode('utf-8')
         try:
-            self._client.retry(self._client.set, key, value.encode('utf-8'), version=index or -1)
+            if retry:
+                self._client.retry(self._client.set, key, value, version=index or -1)
+            else:
+                self._client.set_async(key, value, version=index or -1).get(timeout=1)
             return True
         except NoNodeError:
-            return value == '' or (index is None and self._create(key, value))
+            if do_not_create_empty and not value:
+                return True
+            elif index is None:
+                return self._create(key, value, retry)
+            else:
+                return False
         except Exception:
-            logging.exception('set_failover_value')
-            return False
+            logger.exception('Failed to update %s', key)
+        return False
 
     def set_failover_value(self, value, index=None):
-        return self.__set_failover_or_sync_state_value(self.failover_path, value, index)
+        return self._set_or_create(self.failover_path, value, index)
 
     def set_config_value(self, value, index=None):
-        try:
-            self._client.retry(self._client.set, self.config_path, value.encode('utf-8'), version=index or -1)
-            return True
-        except NoNodeError:
-            return index is None and self._create(self.config_path, value)
-        except Exception:
-            logging.exception('set_config_value')
-            return False
+        return self._set_or_create(self.config_path, value, index, retry=True)
 
     def initialize(self, create_new=True, sysid=""):
-        return self._create(self.initialize_path, sysid, makepath=True) if create_new \
-            else self._client.retry(self._client.set, self.initialize_path, sysid.encode("utf-8"))
+        sysid = sysid.encode('utf-8')
+        return self._create(self.initialize_path, sysid, retry=True) if create_new \
+            else self._client.retry(self._client.set, self.initialize_path, sysid)
 
-    def touch_member(self, data, ttl=None, permanent=False):
+    def touch_member(self, data, permanent=False):
         cluster = self.cluster
         member = cluster and cluster.get_member(self._name, fallback_to_leader=False)
         encoded_data = json.dumps(data, separators=(',', ':')).encode('utf-8')
@@ -262,13 +284,12 @@ class ZooKeeper(AbstractDCS):
             member = None
 
         if member:
-            if deep_compare(data, self._my_member_data):
+            if deep_compare(data, member.data):
                 return True
         else:
             try:
                 self._client.create_async(self.member_path, encoded_data, makepath=True,
                                           ephemeral=not permanent).get(timeout=1)
-                self._my_member_data = data
                 return True
             except Exception as e:
                 if not isinstance(e, NodeExistsError):
@@ -276,7 +297,6 @@ class ZooKeeper(AbstractDCS):
                     return False
         try:
             self._client.set_async(self.member_path, encoded_data).get(timeout=1)
-            self._my_member_data = data
             return True
         except Exception:
             logger.exception('touch_member')
@@ -286,30 +306,14 @@ class ZooKeeper(AbstractDCS):
     def take_leader(self):
         return self.attempt_to_acquire_leader()
 
-    def __write_leader_optime_or_history_value(self, key, value):
-        value = value.encode('utf-8')
-        try:
-            self._client.set_async(key, value).get(timeout=1)
-            return True
-        except NoNodeError:
-            try:
-                self._client.create_async(key, value, makepath=True).get(timeout=1)
-                return True
-            except Exception:
-                logger.exception('Failed to create %s', key)
-        except Exception:
-            logger.exception('Failed to update %s', key)
-        return False
-
     def _write_leader_optime(self, last_operation):
-        return self.__write_leader_optime_or_history_value(self.leader_optime_path, last_operation)
+        return self._set_or_create(self.leader_optime_path, last_operation)
 
     def _update_leader(self):
         return True
 
     def delete_leader(self):
         self._client.restart()
-        self._my_member_data = None
         return True
 
     def _cancel_initialization(self):
@@ -330,10 +334,10 @@ class ZooKeeper(AbstractDCS):
             return True
 
     def set_history_value(self, value):
-        return self.__write_leader_optime_or_history_value(self.history_path, value)
+        return self._set_or_create(self.history_path, value)
 
     def set_sync_state_value(self, value, index=None):
-        return self.__set_failover_or_sync_state_value(self.sync_path, value, index)
+        return self._set_or_create(self.sync_path, value, index, retry=True, do_not_create_empty=True)
 
     def delete_sync_state(self, index=None):
         return self.set_sync_state_value("{}", index)

patroni/ha.py

@@ -6,37 +6,42 @@ import psycopg2
 import requests
 import sys
 import time
+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.postgresql import ACTION_ON_START
+from patroni.postgresql import ACTION_ON_START, ACTION_ON_ROLE_CHANGE
 from patroni.utils import polling_loop, tzutc
+from patroni.dcs import RemoteMember
 from threading import RLock
 
 logger = logging.getLogger(__name__)
 
 
-class _MemberStatus(namedtuple('_MemberStatus', 'member,reachable,in_recovery,wal_position,tags,watchdog_failed')):
+class _MemberStatus(namedtuple('_MemberStatus', ['member', 'reachable', 'in_recovery', 'timeline',
+                                                 'wal_position', 'tags', 'watchdog_failed'])):
     """Node status distilled from API response:
 
         member - dcs.Member object of the node
         reachable - `!False` if the node is not reachable or is not responding with correct JSON
         in_recovery - `!True` if pg_is_in_recovery() == true
-        wal_position - value of `replayed_location` or `location` from JSON, dependin on its role.
+        timeline - timeline value from JSON
+        wal_position - maximum value of `replayed_location` or `received_location` from JSON
         tags - dictionary with values of different tags (i.e. nofailover)
         watchdog_failed - indicates that watchdog is required by configuration but not available or failed
     """
     @classmethod
     def from_api_response(cls, member, json):
         is_master = json['role'] == 'master'
+        timeline = json.get('timeline', 0)
         wal = not is_master and max(json['xlog'].get('received_location', 0), json['xlog'].get('replayed_location', 0))
-        return cls(member, True, not is_master, wal, json.get('tags', {}), json.get('watchdog_failed', False))
+        return cls(member, True, not is_master, timeline, wal, json.get('tags', {}), json.get('watchdog_failed', False))
 
     @classmethod
     def unknown(cls, member):
-        return cls(member, False, None, 0, {}, False)
+        return cls(member, False, None, 0, 0, {}, False)
 
     def failover_limitation(self):
         """Returns reason why this node can't promote or None if everything is ok."""
@@ -59,6 +64,7 @@ class Ha(object):
         self.old_cluster = None
         self._is_leader = False
         self._is_leader_lock = RLock()
+        self._leader_access_is_restricted = False
         self._was_paused = False
         self._leader_timeline = None
         self.recovering = False
@@ -89,13 +95,32 @@ class Ha(object):
     def is_paused(self):
         return self.check_mode('pause')
 
+    def check_timeline(self):
+        return self.check_mode('check_timeline')
+
+    def get_standby_cluster_config(self):
+        if self.cluster and self.cluster.config and self.cluster.config.modify_index:
+            config = self.cluster.config.data
+        else:
+            config = self.patroni.config.dynamic_configuration
+        return config.get('standby_cluster')
+
+    def is_standby_cluster(self):
+        config = 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:
-            return self._is_leader
+            return self._is_leader > time.time() and not self._leader_access_is_restricted
 
     def set_is_leader(self, value):
         with self._is_leader_lock:
-            self._is_leader = value
+            self._is_leader = time.time() + self.dcs.ttl if value else 0
+
+    def set_leader_access_is_restricted(self, value):
+        with self._is_leader_lock:
+            self._leader_access_is_restricted = value
 
     def load_cluster_from_dcs(self):
         cluster = self.dcs.get_cluster()
@@ -105,9 +130,13 @@ class Ha(object):
             self.old_cluster = cluster
         self.cluster = cluster
 
+        if not self.has_lock(False):
+            self.set_is_leader(False)
+
         self._leader_timeline = None if cluster.is_unlocked() else cluster.leader.timeline
 
     def acquire_lock(self):
+        self.set_leader_access_is_restricted(self.cluster.has_permanent_logical_slots(self.state_handler.name))
         ret = self.dcs.attempt_to_acquire_leader()
         self.set_is_leader(ret)
         return ret
@@ -119,15 +148,16 @@ class Ha(object):
                 last_operation = self.state_handler.last_operation()
             except Exception:
                 logger.exception('Exception when called state_handler.last_operation()')
-        ret = self.dcs.update_leader(last_operation)
+        ret = self.dcs.update_leader(last_operation, self._leader_access_is_restricted)
         self.set_is_leader(ret)
         if ret:
             self.watchdog.keepalive()
         return ret
 
-    def has_lock(self):
+    def has_lock(self, info=True):
         lock_owner = self.cluster.leader and self.cluster.leader.name
-        logger.info('Lock owner: %s; I am %s', lock_owner, self.state_handler.name)
+        if info:
+            logger.info('Lock owner: %s; I am %s', lock_owner, self.state_handler.name)
         return lock_owner == self.state_handler.name
 
     def get_effective_tags(self):
@@ -146,6 +176,10 @@ class Ha(object):
                 'state': self.state_handler.state,
                 'role': self.state_handler.role
             }
+
+            # following two lines are mainly necessary for consul, to avoid creation of master service
+            if data['role'] == 'master' and not self.is_leader():
+                data['role'] = 'promoted'
             tags = self.get_effective_tags()
             if tags:
                 data['tags'] = tags
@@ -173,6 +207,9 @@ class Ha(object):
             return self.dcs.touch_member(data)
 
     def clone(self, clone_member=None, msg='(without leader)'):
+        if self.is_standby_cluster() and not isinstance(clone_member, RemoteMember):
+            clone_member = self.get_remote_member(clone_member)
+
         if self.state_handler.clone(clone_member):
             logger.info('bootstrapped %s', msg)
             cluster = self.dcs.get_cluster()
@@ -190,14 +227,24 @@ class Ha(object):
             self._async_executor.schedule('bootstrap {0}'.format(msg))
             self._async_executor.run_async(self.clone, args=(clone_member, 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()
-                self._async_executor.schedule('bootstrap')
-                self._async_executor.run_async(self.state_handler.bootstrap, args=(self.patroni.config['bootstrap'],))
-                return 'trying to bootstrap a new cluster'
+
+                if self.is_standby_cluster():
+                    self._async_executor.schedule('bootstrap_standby_leader')
+                    self._async_executor.run_async(self.bootstrap_standby_leader)
+                    return 'trying to bootstrap a new standby leader'
+                else:
+                    self._async_executor.schedule('bootstrap')
+                    self._async_executor.run_async(
+                        self.state_handler.bootstrap,
+                        args=(self.patroni.config['bootstrap'],)
+                    )
+                    return 'trying to bootstrap a new cluster'
             else:
                 return 'failed to acquire initialize lock'
         else:
@@ -208,10 +255,34 @@ class Ha(object):
                 return 'trying to ' + msg
             return 'waiting for leader to bootstrap'
 
-    def _handle_rewind(self):
-        if self.state_handler.rewind_needed_and_possible(self.cluster.leader):
-            self._async_executor.schedule('running pg_rewind from ' + self.cluster.leader.name)
-            self._async_executor.run_async(self.state_handler.rewind, (self.cluster.leader,))
+    def bootstrap_standby_leader(self):
+        """ If we found 'standby' key in the configuration, we need to bootstrap
+            not a real master, but a 'standby leader', that will take base backup
+            from a remote master and start follow it.
+        """
+        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)
+        if result:
+            self.state_handler.set_role('standby_leader')
+
+        return result
+
+    def _handle_rewind_or_reinitialize(self):
+        leader = self.get_remote_master() if self.is_standby_cluster() else self.cluster.leader
+        if not self.state_handler.rewind_or_reinitialize_needed_and_possible(leader):
+            return None
+
+        if self.state_handler.can_rewind:
+            self._async_executor.schedule('running pg_rewind from ' + leader.name)
+            self._async_executor.run_async(self.state_handler.rewind, (leader,))
+            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')
+            self._async_executor.run_async(self._do_reinitialize, args=(self.cluster, ))
             return True
 
     def recover(self):
@@ -234,6 +305,7 @@ class Ha(object):
             timeout = None
 
         data = self.state_handler.controldata()
+        logger.info('pg_controldata:\n%s\n', '\n'.join('  {0}: {1}'.format(k, v) for k, v in data.items()))
         if data.get('Database cluster state') in ('in production', 'shutting down', 'in crash recovery') and \
                 not self._crash_recovery_executed and (self.cluster.is_unlocked() or self.state_handler.can_rewind):
             self._crash_recovery_executed = True
@@ -243,30 +315,42 @@ class Ha(object):
 
         self.load_cluster_from_dcs()
 
-        if self.has_lock():
-            msg = "starting as readonly because i had the session lock"
-            node_to_follow = None
-        else:
+        role = 'replica'
+        if self.is_standby_cluster() or not self.has_lock():
             if not self.state_handler.rewind_executed:
                 self.state_handler.trigger_check_diverged_lsn()
-            if self._handle_rewind():
+            if self._handle_rewind_or_reinitialize():
                 return self._async_executor.scheduled_action
-            msg = "starting as a secondary"
-            node_to_follow = self._get_node_to_follow(self.cluster)
+
+            if self.has_lock():  # in standby cluster
+                msg = "starting as a standby leader because i had the session lock"
+                role = 'standby_leader'
+                node_to_follow = self._get_node_to_follow(self.cluster)
+            elif self.is_standby_cluster() and self.cluster.is_unlocked():
+                msg = "trying to follow a remote master because standby cluster is unhealthy"
+                node_to_follow = self.get_remote_master()
+            else:
+                msg = "starting as a secondary"
+                node_to_follow = self._get_node_to_follow(self.cluster)
+        elif self.has_lock():
+            msg = "starting as readonly because i had the session lock"
+            node_to_follow = None
 
         self.recovering = True
 
         self._async_executor.schedule('restarting after failure')
-        self._async_executor.run_async(self.state_handler.follow, (node_to_follow, timeout))
+        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 not self.patroni.replicatefrom or self.patroni.replicatefrom == self.state_handler.name:
-            node_to_follow = cluster.leader
-        else:
+        if self.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
 
         return node_to_follow if node_to_follow and node_to_follow.name != self.state_handler.name else None
 
@@ -279,7 +363,8 @@ class Ha(object):
         node_to_follow = self._get_node_to_follow(self.cluster)
 
         if self.is_paused():
-            if not (self.state_handler.need_rewind and self.state_handler.can_rewind) or self.cluster.is_unlocked():
+            if not (self.state_handler.need_rewind and self.state_handler.can_rewind_or_reinitialize_allowed)\
+                    or self.cluster.is_unlocked():
                 self.state_handler.set_role('master' if is_leader else 'replica')
                 if is_leader:
                     return 'continue to run as master without lock'
@@ -289,12 +374,20 @@ class Ha(object):
             self.demote('immediate-nolock')
             return demote_reason
 
-        if self._handle_rewind():
+        if self._handle_rewind_or_reinitialize():
             return self._async_executor.scheduled_action
 
-        if not self.state_handler.check_recovery_conf(node_to_follow):
+        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.check_recovery_conf(node_to_follow):
             self._async_executor.schedule('changing primary_conninfo and restarting')
-            self._async_executor.run_async(self.state_handler.follow, (node_to_follow,))
+            self._async_executor.run_async(self.state_handler.follow, (node_to_follow, role))
+        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)
 
         return follow_reason
 
@@ -336,7 +429,10 @@ class Ha(object):
                     time.sleep(2)
                     picked, allow_promote = self.state_handler.pick_synchronous_standby(self.cluster)
                 if allow_promote:
-                    cluster = self.dcs.get_cluster()
+                    try:
+                        cluster = self.dcs.get_cluster()
+                    except DCSError:
+                        return logger.warning("Could not get cluster state from DCS during process_sync_replication()")
                     if cluster.sync.leader and cluster.sync.leader != self.state_handler.name:
                         logger.info("Synchronous replication key updated by someone else")
                         return
@@ -408,6 +504,10 @@ class Ha(object):
                         line.append(cluster_history[line[0]][3])
                 self.dcs.set_history_value(json.dumps(history, separators=(',', ':')))
 
+    def enforce_follow_remote_master(self, message):
+        demote_reason = 'cannot be a real master in standby cluster'
+        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():
             if self.state_handler.is_leader():
@@ -437,8 +537,10 @@ class Ha(object):
                     return 'Postponing promotion because synchronous replication state was updated by somebody else'
                 self.state_handler.set_synchronous_standby('*' if self.is_synchronous_mode_strict() else None)
             if self.state_handler.role != 'master':
+                self.set_leader_access_is_restricted(self.cluster.has_permanent_logical_slots(self.state_handler.name))
                 self._async_executor.schedule('promote')
-                self._async_executor.run_async(self.state_handler.promote, args=(self.dcs.loop_wait,))
+                self._async_executor.run_async(self.state_handler.promote,
+                                               args=(self.dcs.loop_wait, self._leader_access_is_restricted))
             return promote_message
 
     @staticmethod
@@ -452,7 +554,7 @@ class Ha(object):
             logger.info('Got response from %s %s: %s', member.name, member.api_url, response.content)
             return _MemberStatus.from_api_response(member, response.json())
         except Exception as e:
-            logger.warning("request failed: GET %s (%s)", member.api_url, e)
+            logger.warning("Request failed to %s: GET %s (%s)", member.name, member.api_url, e)
         return _MemberStatus.unknown(member)
 
     def fetch_nodes_statuses(self, members):
@@ -469,15 +571,23 @@ class Ha(object):
         :returns True when node is lagging
         """
         lag = (self.cluster.last_leader_operation or 0) - wal_position
-        return lag > self.state_handler.config.get('maximum_lag_on_failover', 0)
+        return lag > self.patroni.config.get('maximum_lag_on_failover', 0)
 
     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()
         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
 
+        if not self.is_standby_cluster() and self.check_timeline():
+            cluster_timeline = self.cluster.timeline
+            my_timeline = self.state_handler.replica_cached_timeline(cluster_timeline)
+            if my_timeline < cluster_timeline:
+                logger.info('My timeline %s is behind last known cluster timeline %s', my_timeline, cluster_timeline)
+                return False
+
         # Prepare list of nodes to run check against
         members = [m for m in members if m.name != self.state_handler.name and not m.nofailover and m.api_url]
 
@@ -488,11 +598,13 @@ class Ha(object):
                         logger.warning('Master (%s) is still alive', st.member.name)
                         return False
                     if my_wal_position < st.wal_position:
+                        logger.info('Wal position of %s is ahead of my wal position', st.member.name)
                         return False
         return True
 
     def is_failover_possible(self, members):
         ret = False
+        cluster_timeline = self.cluster.timeline
         members = [m for m in members if m.name != self.state_handler.name and not m.nofailover and m.api_url]
         if members:
             for st in self.fetch_nodes_statuses(members):
@@ -501,6 +613,9 @@ class Ha(object):
                     logger.info('Member %s is %s', st.member.name, not_allowed_reason)
                 elif self.is_lagging(st.wal_position):
                     logger.info('Member %s exceeds maximum replication lag', st.member.name)
+                elif self.check_timeline() and (not st.timeline or st.timeline < cluster_timeline):
+                    logger.info('Timeline %s of member %s is behind the cluster timeline %s',
+                                st.timeline, st.member.name, cluster_timeline)
                 else:
                     ret = True
         else:
@@ -592,10 +707,14 @@ class Ha(object):
 
         return self._is_healthiest_node(members.values())
 
-    def release_leader_key_voluntarily(self):
+    def _delete_leader(self):
+        self.set_is_leader(False)
         self.dcs.delete_leader()
-        self.touch_member()
         self.dcs.reset_cluster()
+
+    def release_leader_key_voluntarily(self):
+        self._delete_leader()
+        self.touch_member()
         logger.info("Leader key released")
 
     def demote(self, mode):
@@ -620,9 +739,11 @@ class Ha(object):
         self.state_handler.stop(mode_control['stop'], checkpoint=mode_control['checkpoint'],
                                 on_safepoint=self.watchdog.disable if self.watchdog.is_running else None)
         self.state_handler.set_role('demoted')
+        self.set_is_leader(False)
 
         if mode_control['release']:
-            self.release_leader_key_voluntarily()
+            with self._async_executor:
+                self.release_leader_key_voluntarily()
             time.sleep(2)  # Give a time to somebody to take the leader lock
         if mode_control['offline']:
             node_to_follow, leader = None, None
@@ -639,7 +760,7 @@ class Ha(object):
         else:
             if self.is_synchronous_mode():
                 self.state_handler.set_synchronous_standby(None)
-            if self.state_handler.rewind_needed_and_possible(leader):
+            if self.state_handler.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)
 
@@ -736,8 +857,18 @@ class Ha(object):
                         logger.info('Cleaning up failover key after acquiring leader lock...')
                         self.dcs.manual_failover('', '')
                 self.load_cluster_from_dcs()
-                return self.enforce_master_role('acquired session lock as a leader',
-                                                'promoted self to leader by acquiring session lock')
+
+                if self.is_standby_cluster():
+                    # standby leader disappeared, and this is a healthiest
+                    # replica, so it should become a new standby leader.
+                    # This imply that 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:
+                    return self.enforce_master_role(
+                        'acquired session lock as a leader',
+                        'promoted self to leader by acquiring session lock'
+                    )
             else:
                 return self.follow('demoted self after trying and failing to obtain lock',
                                    'following new leader after trying and failing to obtain lock')
@@ -760,17 +891,32 @@ class Ha(object):
                 if self.cluster.failover and self.cluster.failover.candidate == self.state_handler.name:
                     return 'waiting to become master after promote...'
 
-                self.dcs.delete_leader()
-                self.dcs.reset_cluster()
+                self._delete_leader()
                 return 'removed leader lock because postgres is not running as master'
 
+            if self.state_handler.is_leader() and self._leader_access_is_restricted:
+                self.state_handler.sync_replication_slots(self.cluster)
+                self.state_handler.call_nowait(ACTION_ON_ROLE_CHANGE)
+                self.set_leader_access_is_restricted(False)
+
             if self.update_lock(True):
                 msg = self.process_manual_failover_from_leader()
                 if msg is not None:
                     return msg
 
-                return self.enforce_master_role('no action.  i am the leader with the lock',
-                                                'promoted self to leader because i had the session lock')
+                if self.is_standby_cluster():
+                    # in case of standby cluster we don't really need to
+                    # enforce anything, since the leader is not a master.
+                    # So just remind the role.
+                    msg = 'no action.  i am the standby leader with the lock' \
+                          if self.state_handler.role == 'standby_leader' else \
+                          'promoted self to a standby leader because i had the session lock'
+                    return self.enforce_follow_remote_master(msg)
+                else:
+                    return self.enforce_master_role(
+                        'no action.  i am the leader with the lock',
+                        'promoted self to leader because i had the session lock'
+                    )
             else:
                 # Either there is no connection to DCS or someone else acquired the lock
                 logger.error('failed to update leader lock')
@@ -783,6 +929,9 @@ class Ha(object):
                     return 'not promoting because failed to update leader lock in DCS'
         else:
             logger.info('does not have lock')
+        if self.is_standby_cluster():
+            return self.follow('cannot be a real master in standby cluster',
+                               'no action.  i am a secondary and i am following a standby leader', refresh=False)
         return self.follow('demoting self because i do not have the lock and i was a leader',
                            'no action.  i am a secondary and i am following a leader', refresh=False)
 
@@ -900,7 +1049,8 @@ class Ha(object):
 
     def _do_reinitialize(self, cluster):
         self.state_handler.stop('immediate')
-        self.state_handler.remove_data_directory()
+        # Commented redundant data directory cleanup here
+        # self.state_handler.remove_data_directory()
 
         clone_member = self.cluster.get_clone_member(self.state_handler.name)
         member_role = 'leader' if clone_member == self.cluster.leader else 'replica'
@@ -913,7 +1063,7 @@ class Ha(object):
             if self.cluster.is_unlocked():
                 return 'Cluster has no leader, can not reinitialize'
 
-            if self.cluster.leader.name == self.state_handler.name:
+            if self.has_lock(False):
                 return 'I am the leader, can not reinitialize'
 
         if force:
@@ -959,8 +1109,7 @@ class Ha(object):
             self.watchdog.disable()
             if self.has_lock():
                 self.state_handler.set_role('demoted')
-                self.dcs.delete_leader()
-                self.dcs.reset_cluster()
+                self._delete_leader()
                 return 'removed leader key after trying and failing to start postgres'
             return 'failed to start postgres'
         self._crash_recovery_executed = False
@@ -993,10 +1142,12 @@ class Ha(object):
         if not self.watchdog.activate():
             logger.error('Cancelling bootstrap because watchdog activation failed')
             self.cancel_initialization()
+        self.state_handler.sync_replication_slots(self.cluster)
         self.dcs.take_leader()
         self.set_is_leader(True)
         self.state_handler.call_nowait(ACTION_ON_START)
         self.load_cluster_from_dcs()
+
         return 'initialized a new cluster'
 
     def handle_starting_instance(self):
@@ -1124,16 +1275,15 @@ class Ha(object):
             if not self.state_handler.is_healthy():
                 if self.is_paused():
                     if self.has_lock():
-                        self.dcs.delete_leader()
-                        self.dcs.reset_cluster()
+                        self._delete_leader()
                         return 'removed leader lock because postgres is not running'
                     # Normally we don't start Postgres in a paused state. We make an exception for the demoted primary
                     # that needs to be started after it had been stopped by demote. When there is no need to call rewind
                     # the demote code follows through to starting Postgres right away, however, in the rewind case
                     # it returns from demote and reaches this point to start PostgreSQL again after rewind. In that
                     # case it makes no sense to continue to recover() unless rewind has finished successfully.
-                    elif (self.state_handler.rewind_failed or
-                          not (self.state_handler.need_rewind and self.state_handler.can_rewind)):
+                    elif self.state_handler.rewind_failed or not self.state_handler.rewind_executed and not \
+                            (self.state_handler.need_rewind and self.state_handler.can_rewind_or_reinitialize_allowed):
                         return 'postgres is not running'
 
                 # try to start dead postgres
@@ -1150,11 +1300,11 @@ class Ha(object):
                 # stops PostgreSQL, therefore, we only reload replication slots if no
                 # asynchronous processes are running (should be always the case for the master)
                 if not self._async_executor.busy and not self.state_handler.is_starting():
+                    self.state_handler.sync_replication_slots(self.cluster)
                     if not self.state_handler.cb_called:
                         if not self.state_handler.is_leader():
                             self.state_handler.trigger_check_diverged_lsn()
                         self.state_handler.call_nowait(ACTION_ON_START)
-                    self.state_handler.sync_replication_slots(self.cluster)
         except DCSError:
             dcs_failed = True
             logger.error('Error communicating with DCS')
@@ -1196,13 +1346,11 @@ class Ha(object):
                              (" Leaving watchdog running." if self.watchdog.is_running else ""))
 
     def watch(self, timeout):
-        cluster = self.cluster
         # watch on leader key changes if the postgres is running and leader is known and current node is not lock owner
-        if not self._async_executor.busy and cluster and cluster.leader \
-                and cluster.leader.name != self.state_handler.name:
-            leader_index = cluster.leader.index
-        else:
+        if self._async_executor.busy or self.cluster.is_unlocked() or self.has_lock(False):
             leader_index = None
+        else:
+            leader_index = self.cluster.leader.index
 
         return self.dcs.watch(leader_index, timeout)
 
@@ -1211,3 +1359,25 @@ class Ha(object):
         no "active" leader watch request in progress.
         This usually happens on the master or if the node is running async action"""
         self.dcs.event.set()
+
+    def get_remote_member(self, member=None):
+        """ In case of standby cluster this will tel us from which remote
+            master to stream. Config can be both patroni config or
+            cluster.config.data
+        """
+        cluster_params = self.get_standby_cluster_config()
+
+        if cluster_params:
+            name = member.name if member else 'remote_master:{}'.format(uuid.uuid1())
+
+            data = {k: v for k, v in cluster_params.items() if k in RemoteMember.allowed_keys()}
+            data['no_replication_slot'] = 'primary_slot_name' not in cluster_params
+            conn_kwargs = member.conn_kwargs() if member else \
+                {k: cluster_params[k] for k in ('host', 'port') if k in cluster_params}
+            if conn_kwargs:
+                data['conn_kwargs'] = conn_kwargs
+
+            return RemoteMember(name, data)
+
+    def get_remote_master(self):
+        return self.get_remote_member()

patroni/log.py

@@ -0,0 +1,66 @@
+import logging
+import os
+
+from copy import deepcopy
+from logging.handlers import RotatingFileHandler
+from patroni.utils import deep_compare
+
+
+class PatroniLogger(object):
+
+    DEFAULT_LEVEL = 'INFO'
+    DEFAULT_FORMAT = '%(asctime)s %(levelname)s: %(message)s'
+
+    def __init__(self):
+        self.root_logger = logging.getLogger()
+        self.config = None
+        self.handler = None
+        self.reload_config({'level': 'DEBUG'})
+
+    def update_loggers(self):
+        loggers = deepcopy(self.config.get('loggers') or {})
+        for name, logger in self.root_logger.manager.loggerDict.items():
+            if not isinstance(logger, logging.PlaceHolder):
+                level = loggers.pop(name, logging.NOTSET)
+                logger.setLevel(level)
+
+        for name, level in loggers.items():
+            logger = self.root_logger.manager.getLogger(name)
+            logger.setLevel(level)
+
+    def reload_config(self, config):
+        if self.config is None or not deep_compare(self.config, config):
+            self.root_logger.setLevel(config.get('level', PatroniLogger.DEFAULT_LEVEL))
+
+            add_handler = None
+            if 'dir' in config:
+                if not isinstance(self.handler, RotatingFileHandler):
+                    add_handler = RotatingFileHandler(os.path.join(config['dir'], __name__))
+                handler = add_handler or self.handler
+                handler.maxBytes = int(config.get('file_size', 25000000))
+                handler.backupCount = int(config.get('file_num', 4))
+            else:
+                if self.handler is None or isinstance(self.handler, RotatingFileHandler):
+                    add_handler = logging.StreamHandler()
+                handler = add_handler or self.handler
+
+            oldlogformat = (self.config or {}).get('format', PatroniLogger.DEFAULT_FORMAT)
+            logformat = config.get('format', PatroniLogger.DEFAULT_FORMAT)
+
+            olddateformat = (self.config or {}).get('dateformat') or None
+            dateformat = config.get('dateformat') or None  # Convert empty string to `None`
+
+            if oldlogformat != logformat or olddateformat != dateformat or add_handler:
+                handler.setFormatter(logging.Formatter(logformat, dateformat))
+
+            if add_handler:
+                self.root_logger.addHandler(add_handler)
+
+                if self.handler is not None:
+                    self.root_logger.removeHandler(self.handler)
+                    self.handler.close()
+
+                self.handler = add_handler
+
+            self.config = config.copy()
+            self.update_loggers()

patroni/postgresql.py

@@ -5,6 +5,7 @@ import re
 import shlex
 import shutil
 import socket
+import stat
 import subprocess
 import tempfile
 import time
@@ -15,11 +16,13 @@ from patroni.callback_executor import CallbackExecutor
 from patroni.exceptions import PostgresConnectionException, PostgresException
 from patroni.utils import compare_values, parse_bool, parse_int, Retry, RetryFailedError, polling_loop, split_host_port
 from patroni.postmaster import PostmasterProcess
+from patroni.dcs import slot_name_from_member_name, RemoteMember, Leader
 from requests.structures import CaseInsensitiveDict
 from six import string_types
 from six.moves.urllib.parse import quote_plus
 from threading import current_thread, Lock
 
+
 logger = logging.getLogger(__name__)
 
 ACTION_ON_START = "on_start"
@@ -27,6 +30,7 @@ ACTION_ON_STOP = "on_stop"
 ACTION_ON_RESTART = "on_restart"
 ACTION_ON_RELOAD = "on_reload"
 ACTION_ON_ROLE_CHANGE = "on_role_change"
+ACTION_NOOP = "noop"
 
 STATE_RUNNING = 'running'
 STATE_REJECT = 'rejecting connections'
@@ -35,14 +39,16 @@ STATE_UNKNOWN = 'unknown'
 
 STOP_POLLING_INTERVAL = 1
 REWIND_STATUS = type('Enum', (), {'INITIAL': 0, 'CHECK': 1, 'NEED': 2, 'NOT_NEED': 3, 'SUCCESS': 4, 'FAILED': 5})
-sync_standby_name_re = re.compile('^[A-Za-z_][A-Za-z_0-9\$]*$')
+sync_standby_name_re = re.compile(r'^[A-Za-z_][A-Za-z_0-9\$]*$')
 
-cluster_info_query = ("SELECT CASE WHEN pg_is_in_recovery() THEN 0 "
-                      "ELSE ('x' || SUBSTR(pg_{0}file_name(pg_current_{0}_{1}()), 1, 8))::bit(32)::int END, "
-                      "CASE WHEN pg_is_in_recovery() THEN GREATEST("
-                      " pg_{0}_{1}_diff(COALESCE(pg_last_{0}_receive_{1}(), '0/0'), '0/0')::bigint,"
-                      " pg_{0}_{1}_diff(pg_last_{0}_replay_{1}(), '0/0')::bigint)"
-                      "ELSE pg_{0}_{1}_diff(pg_current_{0}_{1}(), '0/0')::bigint END")
+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")
 
 
 def quote_ident(value):
@@ -50,22 +56,6 @@ def quote_ident(value):
     return value if sync_standby_name_re.match(value) else '"' + value + '"'
 
 
-def slot_name_from_member_name(member_name):
-    """Translate member name to valid PostgreSQL slot name.
-
-    PostgreSQL replication slot names must be valid PostgreSQL names. This function maps the wider space of
-    member names to valid PostgreSQL names. Names are lowercased, dashes and periods common in hostnames
-    are replaced with underscores, other characters are encoded as their unicode codepoint. Name is truncated
-    to 64 characters. Multiple different member names may map to a single slot name."""
-
-    def replace_char(match):
-        c = match.group(0)
-        return '_' if c in '-.' else "u{:04d}".format(ord(c))
-
-    slot_name = re.sub('[^a-z0-9_]', replace_char, member_name.lower())
-    return slot_name[0:63]
-
-
 @contextmanager
 def null_context():
     yield
@@ -152,7 +142,7 @@ class Postgresql(object):
         self._connection = None
         self._cursor_holder = None
         self._sysid = None
-        self._replication_slots = []  # list of already existing replication slots
+        self._replication_slots = {}  # already existing replication slots
         self.retry = Retry(max_tries=-1, deadline=config['retry_timeout']/2.0, max_delay=1,
                            retry_exceptions=PostgresConnectionException)
 
@@ -322,8 +312,8 @@ class Postgresql(object):
                     changes['wal_segment_size'] = '16384kB'
                 # XXX: query can raise an exception
                 for r in self.query("""SELECT name, setting, unit, vartype, context
-                                         FROM pg_settings
-                                        WHERE LOWER(name) IN (""" + ', '.join(['%s'] * len(changes)) + """)
+                                         FROM pg_catalog.pg_settings
+                                        WHERE pg_catalog.lower(name) IN (""" + ', '.join(['%s'] * len(changes)) + """)
                                         ORDER BY 1 DESC""", *(k.lower() for k in changes.keys())):
                     if r[4] == 'internal':
                         if r[0] == 'wal_segment_size':
@@ -403,7 +393,7 @@ class Postgresql(object):
             we have either wal_log_hints or checksums turned on
         """
         # low-hanging fruit: check if pg_rewind configuration is there
-        if not (self.config.get('use_pg_rewind') and all(self._superuser.get(n) for n in ('username', 'password'))):
+        if not self.config.get('use_pg_rewind'):
             return False
 
         cmd = [self._pgcommand('pg_rewind'), '--help']
@@ -415,6 +405,10 @@ class Postgresql(object):
             return False
         return self.configuration_allows_rewind(self.controldata())
 
+    @property
+    def can_rewind_or_reinitialize_allowed(self):
+        return self.config.get('remove_data_directory_on_diverged_timelines') or self.can_rewind
+
     @property
     def sysid(self):
         if not self._sysid and not self.bootstrapping:
@@ -638,7 +632,8 @@ class Postgresql(object):
             return os.environ.copy()
 
         with open(self._pgpass, 'w') as f:
-            os.fchmod(f.fileno(), 0o600)
+            if os.name != 'nt':
+                os.fchmod(f.fileno(), 0o600)
             f.write('{host}:{port}:*:{user}:{password}\n'.format(**record))
 
         env = os.environ.copy()
@@ -665,9 +660,17 @@ class Postgresql(object):
         self.set_state('creating replica')
         self._sysid = None
 
-        # get list of replica methods from config.
-        # If there is no configuration key, or no value is specified, use basebackup
-        replica_methods = self._create_replica_methods or ['basebackup']
+        is_remote_master = isinstance(clone_member, RemoteMember)
+        create_replica_methods = is_remote_master and clone_member.create_replica_methods
+
+        # get list of replica methods either from clone member or from
+        # the config. If there is no configuration key, or no value is
+        # specified, use basebackup
+        replica_methods = (
+            create_replica_methods
+            or self._create_replica_methods
+            or ['basebackup']
+        )
 
         if clone_member and clone_member.conn_url:
             r = clone_member.conn_kwargs(self._replication)
@@ -696,7 +699,10 @@ class Postgresql(object):
                     break
             else:
                 if not self.data_directory_empty():
-                    self.remove_data_directory()
+                    if self.config.get(replica_method, {}).get('keep_data', False):
+                        logger.info('Leaving data directory uncleaned')
+                    else:
+                        self.remove_data_directory()
 
                 cmd = replica_method
                 method_config = {}
@@ -709,10 +715,14 @@ class Postgresql(object):
                     cmd = method_config.pop('command', cmd)
 
                 # add the default parameters
-                method_config.update({"scope": self.scope,
-                                      "role": "replica",
-                                      "datadir": self._data_dir,
-                                      "connstring": connstring})
+                if not method_config.get('no_params', False):
+                    method_config.update({"scope": self.scope,
+                                          "role": "replica",
+                                          "datadir": self._data_dir,
+                                          "connstring": connstring})
+                else:
+                    for param in ('no_params', 'no_master', 'keep_data'):
+                        method_config.pop(param, None)
                 params = ["--{0}={1}".format(arg, val) for arg, val in method_config.items()]
                 try:
                     # call script with the full set of parameters
@@ -862,7 +872,7 @@ class Postgresql(object):
                 self._pending_restart = True
         return effective_configuration
 
-    def start(self, timeout=None, block_callbacks=False, task=None):
+    def start(self, timeout=None, task=None, block_callbacks=False, role=None):
         """Start PostgreSQL
 
         Waits for postmaster to open ports or terminate so pg_isready can be used to check startup completion
@@ -882,7 +892,7 @@ class Postgresql(object):
         if not block_callbacks:
             self.__cb_pending = ACTION_ON_START
 
-        self.set_role(self.get_postgres_role_from_data_directory())
+        self.set_role(role or self.get_postgres_role_from_data_directory())
 
         self.set_state('starting')
         self._pending_restart = False
@@ -940,12 +950,12 @@ class Postgresql(object):
             with self._get_connection_cursor(**connect_kwargs) as cur:
                 cur.execute("SET statement_timeout = 0")
                 if check_not_is_in_recovery:
-                    cur.execute('SELECT pg_is_in_recovery()')
+                    cur.execute('SELECT pg_catalog.pg_is_in_recovery()')
                     if cur.fetchone()[0]:
                         return 'is_in_recovery=true'
                 return cur.execute('CHECKPOINT')
         except psycopg2.Error:
-            logging.exception('Exception during CHECKPOINT')
+            logger.exception('Exception during CHECKPOINT')
             return 'not accessible or not healty'
 
     def stop(self, mode='fast', block_callbacks=False, checkpoint=None, on_safepoint=None):
@@ -1083,7 +1093,7 @@ class Postgresql(object):
 
         return self.state == 'running'
 
-    def restart(self, timeout=None, task=None):
+    def restart(self, timeout=None, task=None, block_callbacks=False, role=None):
         """Restarts PostgreSQL.
 
         When timeout parameter is set the call will block either until PostgreSQL has started, failed to start or
@@ -1092,8 +1102,9 @@ class Postgresql(object):
         :returns: True when restart was successful and timeout did not expire when waiting.
         """
         self.set_state('restarting')
-        self.__cb_pending = ACTION_ON_RESTART
-        ret = self.stop(block_callbacks=True) and self.start(timeout=timeout, block_callbacks=True, task=task)
+        if not block_callbacks:
+            self.__cb_pending = ACTION_ON_RESTART
+        ret = self.stop(block_callbacks=True) and self.start(timeout, task, True, role)
         if not ret and not self.is_starting():
             self.set_state('restart failed ({0})'.format(self.state))
         return ret
@@ -1107,16 +1118,21 @@ class Postgresql(object):
             f.write(self._CONFIG_WARNING_HEADER)
             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()):
-                if not self._running_custom_bootstrap or name != 'hba_file':
+                if not self._running_custom_bootstrap or name not in ('hba_file', 'archive_mode'):
                     f.write("{0} = '{1}'\n".format(name, value))
+            # we want to set archive_mode to 'off' during the custom bootstrap
+            # in order to avoid premature archiving of wals and history files
+            if self._running_custom_bootstrap:
+                f.write("archive_mode = 'off'\n")
             # 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._running_custom_bootstrap or 'hba_file' not in self._server_parameters:
-                f.write("hba_file = '{0}'\n".format(self._pg_hba_conf))
+                f.write("hba_file = '{0}'\n".format(self._pg_hba_conf.replace('\\', '\\\\')))
             if 'ident_file' not in self._server_parameters:
-                f.write("ident_file = '{0}'\n".format(os.path.join(self._config_dir, 'pg_ident.conf')))
+                s = "ident_file = '{0}'\n".format(os.path.join(self._config_dir, 'pg_ident.conf').replace('\\', '\\\\'))
+                f.write(s)
 
     def is_healthy(self):
         if not self.is_running():
@@ -1150,8 +1166,10 @@ class Postgresql(object):
             with open(self._pg_hba_conf, 'w') as f:
                 f.write(self._CONFIG_WARNING_HEADER)
                 for address, t in addresses.items():
-                    f.write('{0}\t{1}\t{2}\t{3}\ttrust\n'.format(t, 'all',
-                                                                 self._superuser.get('username') or 'all', address))
+                    f.write((
+                        '{0}\treplication\t{1}\t{3}\ttrust\n'
+                        '{0}\tall\t{2}\t{3}\ttrust\n'
+                    ).format(t, self._replication['username'], self._superuser.get('username') or 'all', address))
         elif not self._server_parameters.get('hba_file') and self.config.get('pg_hba'):
             with open(self._pg_hba_conf, 'w') as f:
                 f.write(self._CONFIG_WARNING_HEADER)
@@ -1182,6 +1200,7 @@ class Postgresql(object):
 
     def write_recovery_conf(self, recovery_params):
         with open(self._recovery_conf, 'w') as f:
+            os.chmod(self._recovery_conf, stat.S_IWRITE | stat.S_IREAD)
             for name, value in recovery_params.items():
                 f.write("{0} = '{1}'\n".format(name, value))
 
@@ -1192,7 +1211,7 @@ class Postgresql(object):
             ('user', r.get('user')),
             ('host', r.get('host')),
             ('port', r.get('port')),
-            ('dbname', r.get('database')),
+            ('dbname', r.get('database') or self._database),
             ('sslmode', 'prefer'),
             ('sslcompression', '1'),
         ]
@@ -1211,12 +1230,15 @@ class Postgresql(object):
         # Don't try to call pg_controldata during backup restore
         if self._version_file_exists() and self.state != 'creating replica':
             try:
-                data = subprocess.check_output([self._pgcommand('pg_controldata'), self._data_dir],
-                                               env={'LANG': 'C', 'LC_ALL': 'C', 'PATH': os.environ['PATH']})
+                env = {'LANG': 'C', 'LC_ALL': 'C', 'PATH': os.getenv('PATH')}
+                if os.getenv('SYSTEMROOT') is not None:
+                    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()
                     # pg_controldata output depends on major verion. Some of parameters are prefixed by 'Current '
-                    result = {l.split(':')[0].replace('Current ', '', 1): l.split(':', 1)[1].strip() for l in data if l}
+                    result = {l.split(':')[0].replace('Current ', '', 1): l.split(':', 1)[1].strip() for l in data
+                              if l and ':' in l}
             except subprocess.CalledProcessError:
                 logger.exception("Error when calling pg_controldata")
         return result
@@ -1234,8 +1256,8 @@ class Postgresql(object):
                 yield cur
 
     @contextmanager
-    def _get_replication_connection_cursor(self, host='localhost', port=5432, **kwargs):
-        with self._get_connection_cursor(host=host, port=int(port), database=self._database, replication=1,
+    def _get_replication_connection_cursor(self, host='localhost', port=5432, database=None, **kwargs):
+        with self._get_connection_cursor(host=host, port=int(port), database=database or self._database, replication=1,
                                          user=self._replication['username'], password=self._replication['password'],
                                          connect_timeout=3, options='-c statement_timeout=2000') as cur:
             yield cur
@@ -1243,7 +1265,7 @@ class Postgresql(object):
     def check_leader_is_not_in_recovery(self, **kwargs):
         try:
             with self._get_connection_cursor(connect_timeout=3, options='-c statement_timeout=2000', **kwargs) as cur:
-                cur.execute('SELECT pg_is_in_recovery()')
+                cur.execute('SELECT pg_catalog.pg_is_in_recovery()')
                 if not cur.fetchone()[0]:
                     return True
                 logger.info('Leader is still in_recovery and therefore can\'t be used for rewind')
@@ -1306,7 +1328,11 @@ class Postgresql(object):
         if local_timeline is None or local_lsn is None:
             return
 
-        if not self.check_leader_is_not_in_recovery(**leader.conn_kwargs(self._superuser)):
+        if isinstance(leader, Leader):
+            if leader.member.data.get('role') != 'master':
+                return
+        # standby cluster
+        elif not self.check_leader_is_not_in_recovery(**leader.conn_kwargs(self._superuser)):
             return
 
         history = need_rewind = None
@@ -1354,10 +1380,10 @@ class Postgresql(object):
         history_path = 'pg_{0}/{1:08X}.history'.format(self.wal_name, timeline)
         try:
             cursor = self._cursor()
-            cursor.execute('SELECT isdir, modification FROM pg_stat_file(%s)', (history_path,))
+            cursor.execute('SELECT isdir, modification FROM pg_catalog.pg_stat_file(%s)', (history_path,))
             isdir, modification = cursor.fetchone()
             if not isdir:
-                cursor.execute('SELECT pg_read_file(%s)', (history_path,))
+                cursor.execute('SELECT pg_catalog.pg_read_file(%s)', (history_path,))
                 history = list(self.parse_history(cursor.fetchone()[0]))
                 if history[-1][0] == timeline - 1:
                     history[-1].append(modification.isoformat())
@@ -1386,19 +1412,21 @@ class Postgresql(object):
         else:
             logger.error('Failed to rewind from healty master: %s', leader.name)
 
-            if self.config.get('remove_data_directory_on_rewind_failure', False):
-                logger.warning('remove_data_directory_on_rewind_failure is set. removing...')
-                self.remove_data_directory()
-                self._rewind_state = REWIND_STATUS.INITIAL
+            for name in ('remove_data_directory_on_rewind_failure', 'remove_data_directory_on_diverged_timelines'):
+                if self.config.get(name):
+                    logger.warning('%s is set. removing...', name)
+                    self.remove_data_directory()
+                    self._rewind_state = REWIND_STATUS.INITIAL
+                    break
             else:
                 self._rewind_state = REWIND_STATUS.FAILED
         return False
 
     def trigger_check_diverged_lsn(self):
-        if self.can_rewind and self._rewind_state != REWIND_STATUS.NEED:
+        if self.can_rewind_or_reinitialize_allowed and self._rewind_state != REWIND_STATUS.NEED:
             self._rewind_state = REWIND_STATUS.CHECK
 
-    def rewind_needed_and_possible(self, leader):
+    def rewind_or_reinitialize_needed_and_possible(self, leader):
         if leader and leader.name != self.name and leader.conn_url and self._rewind_state == REWIND_STATUS.CHECK:
             self._check_timeline_and_lsn(leader)
         return leader and leader.conn_url and self._rewind_state == REWIND_STATUS.NEED
@@ -1411,24 +1439,45 @@ class Postgresql(object):
     def rewind_failed(self):
         return self._rewind_state == REWIND_STATUS.FAILED
 
-    def follow(self, member, timeout=None):
+    def follow(self, member, role='replica', timeout=None):
+        is_remote_master = isinstance(member, RemoteMember)
+        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.primary_conninfo(member)
-        change_role = self.role in ('master', 'demoted')
+        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.use_slots:
-            recovery_params['primary_slot_name'] = slot_name_from_member_name(self.name)
+        if self.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.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
+        if change_role:
+            self.__cb_pending = ACTION_NOOP
+
         if self.is_running():
-            self.restart()
+            self.restart(block_callbacks=change_role, role=role)
         else:
-            self.start(timeout=timeout)
-        self.set_role('replica')
+            self.start(timeout=timeout, block_callbacks=change_role, role=role)
 
         if change_role:
             # TODO: postpone this until start completes, or maybe do even earlier
@@ -1467,12 +1516,12 @@ class Postgresql(object):
             logger.exception('unable to restore configuration files from backup')
 
     def _wait_promote(self, wait_seconds):
-        for _ in polling_loop(wait_seconds - 1):
+        for _ in polling_loop(wait_seconds):
             data = self.controldata()
             if data.get('Database cluster state') == 'in production':
                 return True
 
-    def promote(self, wait_seconds):
+    def promote(self, wait_seconds, access_is_restricted=False):
         if self.role == 'master':
             return True
         ret = self.pg_ctl('promote', '-W')
@@ -1480,7 +1529,8 @@ class Postgresql(object):
             self.set_role('master')
             logger.info("cleared rewind state after becoming the leader")
             self._rewind_state = REWIND_STATUS.INITIAL
-            self.call_nowait(ACTION_ON_ROLE_CHANGE)
+            if not access_is_restricted:
+                self.call_nowait(ACTION_ON_ROLE_CHANGE)
             ret = self._wait_promote(wait_seconds)
         return ret
 
@@ -1513,59 +1563,88 @@ $$""".format(name, ' '.join(options)), name, password, password)
 
     def load_replication_slots(self):
         if self.use_slots and self._schedule_load_slots:
-            cursor = self._query("SELECT slot_name FROM pg_replication_slots WHERE slot_type='physical'")
-            self._replication_slots = [r[0] for r in cursor]
+            replication_slots = {}
+            cursor = self._query('SELECT slot_name, slot_type, plugin, database FROM pg_catalog.pg_replication_slots')
+            for r in cursor:
+                value = {'type': r[1]}
+                if r[1] == 'logical':
+                    value.update({'plugin': r[2], 'database': r[3]})
+                replication_slots[r[0]] = value
+            self._replication_slots = replication_slots
             self._schedule_load_slots = False
 
     def postmaster_start_time(self):
         try:
-            cursor = self.query("""SELECT to_char(pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ')""")
+            cursor = self.query("SELECT pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(),"
+                                " 'YYYY-MM-DD HH24:MI:SS.MS TZ')")
             return cursor.fetchone()[0]
         except psycopg2.Error:
             return None
 
+    def drop_replication_slot(self, name):
+        cursor = self._query(('SELECT pg_catalog.pg_drop_replication_slot(%s) WHERE EXISTS (SELECT 1 ' +
+                              'FROM pg_catalog.pg_replication_slots WHERE slot_name = %s AND NOT active)'), name, name)
+        # In normal situation rowcount should be 1, otherwise either slot doesn't exists or it is still active
+        return cursor.rowcount == 1
+
+    @staticmethod
+    def compare_slots(s1, s2):
+        return s1['type'] == s2['type'] and\
+                (s1['type'] == 'physical' or s1['database'] == s2['database'] and s1['plugin'] == s2['plugin'])
+
     def sync_replication_slots(self, cluster):
         if self.use_slots:
             try:
                 self.load_replication_slots()
-                # 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
-                if self.role == 'master':
-                    slot_members = [m.name for m in cluster.members if m.name != self.name and
-                                    (m.replicatefrom is None or m.replicatefrom == self.name or
-                                     not cluster.has_member(m.replicatefrom))]
-                else:
-                    # only manage slots for replicas that replicate from this one, except for the leader among them
-                    slot_members = [m.name for m in cluster.members if m.replicatefrom == self.name and
-                                    m.name != cluster.leader.name]
-                slots = set(slot_name_from_member_name(name) for name in slot_members)
 
-                if len(slots) < len(slot_members):
-                    # Find which names are conflicting for a nicer error message
-                    slot_conflicts = defaultdict(list)
-                    for name in slot_members:
-                        slot_conflicts[slot_name_from_member_name(name)].append(name)
-                    logger.error("Following cluster members share a replication slot name: %s",
-                                 "; ".join("{} map to {}".format(", ".join(v), k)
-                                           for k, v in slot_conflicts.items() if len(v) > 1))
+                slots = cluster.get_replication_slots(self.name, self.role)
 
-                # drop unused slots
-                for slot in set(self._replication_slots) - slots:
-                    cursor = self._query("""SELECT pg_drop_replication_slot(%s)
-                                             WHERE EXISTS(SELECT 1 FROM pg_replication_slots
-                                             WHERE slot_name = %s AND NOT active)""", slot, slot)
+                # drop old replication slots which are not presented in desired slots
+                for name in set(self._replication_slots) - set(slots):
+                    if not self.drop_replication_slot(name):
+                        logger.error("Failed to drop replication slot '%s'", name)
+                        self._schedule_load_slots = True
 
-                    if cursor.rowcount != 1:  # Either slot doesn't exists or it is still active
-                        self._schedule_load_slots = True  # schedule load_replication_slots on the next iteration
+                immediately_reserve = ', true' if self._major_version >= 90600 else ''
 
-                # create new slots
-                for slot in slots - set(self._replication_slots):
-                    self._query("""SELECT pg_create_physical_replication_slot(%s)
-                                    WHERE NOT EXISTS (SELECT 1 FROM pg_replication_slots
-                                    WHERE slot_name = %s)""", slot, slot)
+                logical_slots = defaultdict(dict)
+                for name, value in slots.items():
+                    if name in self._replication_slots and not self.compare_slots(value, self._replication_slots[name]):
+                        logger.info("Trying to drop replication slot '%s' because value is changing from %s to %s",
+                                    name, self._replication_slots[name], value)
+                        if not self.drop_replication_slot(name):
+                            logger.error("Failed to drop replication slot '%s'", name)
+                            self._schedule_load_slots = True
+                            continue
+                        self._replication_slots.pop(name)
+                    if name not in self._replication_slots:
+                        if value['type'] == 'physical':
+                            try:
+                                self._query(("SELECT pg_catalog.pg_create_physical_replication_slot(%s{0})" +
+                                             " WHERE NOT EXISTS (SELECT 1 FROM pg_catalog.pg_replication_slots" +
+                                             " WHERE slot_type = 'physical' AND slot_name = %s)").format(
+                                                 immediately_reserve), name, name)
+                            except Exception:
+                                logger.exception("Failed to create physical replication slot '%s'", name)
+                                self._schedule_load_slots = True
+                        elif value['type'] == 'logical' and name not in self._replication_slots:
+                            logical_slots[value['database']][name] = value
 
+                # create new logical slots
+                for database, values in logical_slots.items():
+                    conn_kwargs = self._local_connect_kwargs
+                    conn_kwargs['database'] = database
+                    with self._get_connection_cursor(**conn_kwargs) as cur:
+                        for name, value in values.items():
+                            try:
+                                cur.execute("SELECT pg_catalog.pg_create_logical_replication_slot(%s, %s)" +
+                                            " WHERE NOT EXISTS (SELECT 1 FROM pg_catalog.pg_replication_slots" +
+                                            " WHERE slot_type = 'logical' AND slot_name = %s)",
+                                            (name, value['plugin'], name))
+                            except Exception:
+                                logger.exception("Failed to create logical replication slot '%s' plugin='%s'",
+                                                 name, value['plugin'])
+                                self._schedule_load_slots = True
                 self._replication_slots = slots
             except Exception:
                 logger.exception('Exception when changing replication slots')
@@ -1591,6 +1670,7 @@ $$""".format(name, ' '.join(options)), name, password, password)
                base backup)
         """
 
+        self._rewind_state = REWIND_STATUS.INITIAL
         ret = self.create_replica(clone_member) == 0
         if ret:
             self._post_restore()
@@ -1612,7 +1692,8 @@ $$""".format(name, ' '.join(options)), name, password, password)
 
     def post_bootstrap(self, config, task):
         try:
-            self.create_or_update_role(self._superuser['username'], self._superuser['password'], ['SUPERUSER'])
+            if 'username' in self._superuser and 'password' in self._superuser:
+                self.create_or_update_role(self._superuser['username'], self._superuser['password'], ['SUPERUSER'])
 
             task.complete(self.run_bootstrap_post_init(config))
             if task.result:
@@ -1631,17 +1712,11 @@ $$""".format(name, ' '.join(options)), name, password, password)
                         os.unlink(self._pg_hba_conf)
                         self.restore_configuration_files()
                     self._write_postgresql_conf()
-                    if self._server_parameters.get('hba_file') and \
-                            self._server_parameters['hba_file'] != self._pg_hba_conf:
-                        self.restart()
-                    else:
-                        self._replace_pg_hba()
-                        if self.pending_restart:
-                            self.restart()
-                        else:
-                            self.reload()
-                            time.sleep(1)  # give a time to postgres to "reload" configuration files
-                            self.close_connection()  # close connection to reconnect with a new password
+                    self._replace_pg_hba()
+                    # at this point there should be no recovery.conf
+                    if os.path.isfile(self._recovery_conf) or os.path.islink(self._recovery_conf):
+                        os.unlink(self._recovery_conf)
+                    self.restart()
         except Exception:
             logger.exception('post_bootstrap')
             task.complete(False)
@@ -1667,6 +1742,16 @@ $$""".format(name, ' '.join(options)), name, password, password)
             elif os.path.isfile(self._data_dir):
                 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
+                # should clean the target
+                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)
+                        logger.info('Removing WAL directory: %s', pg_wal_realpath)
+                        shutil.rmtree(pg_wal_realpath)
+
                 shutil.rmtree(self._data_dir)
         except (IOError, OSError):
             logger.exception('Could not remove data directory %s', self._data_dir)
@@ -1722,9 +1807,9 @@ $$""".format(name, ' '.join(options)), name, password, password)
         # Pick candidates based on who has flushed WAL farthest.
         # TODO: for synchronous_commit = remote_write we actually want to order on write_location
         for app_name, state, sync_state in self.query(
-                """SELECT LOWER(application_name), state, sync_state
-                     FROM pg_stat_replication
-                    ORDER BY flush_{0} DESC""".format(self.lsn_name)):
+                "SELECT pg_catalog.lower(application_name), state, sync_state"
+                " FROM pg_catalog.pg_stat_replication"
+                " ORDER BY flush_{0} DESC".format(self.lsn_name)):
             member = members.get(app_name)
             if state != 'streaming' or not member or member.tags.get('nosync', False):
                 continue
@@ -1733,7 +1818,7 @@ $$""".format(name, ' '.join(options)), name, password, password)
             if sync_state == 'potential' and app_name == current:
                 # Prefer current even if not the best one any more to avoid indecisivness and spurious swaps.
                 return current, False
-            if sync_state == 'async':
+            if sync_state in ('async', 'potential'):
                 candidates.append(app_name)
 
         if candidates:

patroni/postmaster.py

@@ -1,21 +1,32 @@
 import logging
+import multiprocessing
 import os
 import psutil
 import re
 import signal
 import subprocess
 
-from patroni import call_self
-
 logger = logging.getLogger(__name__)
 
 STOP_SIGNALS = {
     'smart': signal.SIGTERM,
     'fast': signal.SIGINT,
-    'immediate': signal.SIGQUIT,
+    'immediate': signal.SIGQUIT if os.name != 'nt' else signal.SIGABRT,
 }
 
 
+def pg_ctl_start(conn, cmdline, env):
+    if os.name != 'nt':
+        os.setsid()
+    try:
+        postmaster = subprocess.Popen(cmdline, close_fds=True, env=env)
+        conn.send(postmaster.pid)
+    except Exception:
+        logger.exception('Failed to execute %s', cmdline)
+        conn.send(None)
+    conn.close()
+
+
 class PostmasterProcess(psutil.Process):
 
     def __init__(self, pid):
@@ -102,28 +113,31 @@ class PostmasterProcess(psutil.Process):
         return None
 
     def wait_for_user_backends_to_close(self):
-        # These regexps are cross checked against versions PostgreSQL 9.1 .. 9.6
-        aux_proc_re = re.compile("(?:postgres:)( .*:)? (?:""(?:startup|logger|checkpointer|writer|wal writer|"
-                                 "autovacuum launcher|autovacuum worker|stats collector|wal receiver|archiver|"
-                                 "wal sender) process|bgworker: )")
+        # These regexps are cross checked against versions PostgreSQL 9.1 .. 11
+        aux_proc_re = re.compile("(?:postgres:)( .*:)? (?:(?:archiver|startup|autovacuum launcher|autovacuum worker|"
+                                 "checkpointer|logger|stats collector|wal receiver|wal writer|writer)(?: process  )?|"
+                                 "walreceiver|wal sender process|walsender|walwriter|background writer|"
+                                 "logical replication launcher|logical replication worker for|bgworker:) ")
 
         try:
-            user_backends = []
-            user_backends_cmdlines = []
-            for child in self.children():
-                try:
-                    cmdline = child.cmdline()[0]
-                    if not aux_proc_re.match(cmdline):
-                        user_backends.append(child)
-                        user_backends_cmdlines.append(cmdline)
-                except psutil.NoSuchProcess:
-                    pass
-            if user_backends:
-                logger.debug('Waiting for user backends %s to close', ', '.join(user_backends_cmdlines))
-                psutil.wait_procs(user_backends)
-            logger.debug("Backends closed")
+            children = self.children()
         except psutil.Error:
-            logger.exception('wait_for_user_backends_to_close')
+            return logger.debug('Failed to get list of postmaster children')
+
+        user_backends = []
+        user_backends_cmdlines = []
+        for child in children:
+            try:
+                cmdline = child.cmdline()[0]
+                if not aux_proc_re.match(cmdline):
+                    user_backends.append(child)
+                    user_backends_cmdlines.append(cmdline)
+            except psutil.NoSuchProcess:
+                pass
+        if user_backends:
+            logger.debug('Waiting for user backends %s to close', ', '.join(user_backends_cmdlines))
+            psutil.wait_procs(user_backends)
+        logger.debug("Backends closed")
 
     @staticmethod
     def start(pgcommand, data_dir, conf, options):
@@ -138,7 +152,8 @@ class PostmasterProcess(psutil.Process):
         # of init process to take care about postmaster.
         # 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.
-        env = {p: os.environ[p] for p in ('PATH', 'LD_LIBRARY_PATH', 'LC_ALL', 'LANG') if p in os.environ}
+        # 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}
         try:
             proc = PostmasterProcess._from_pidfile(data_dir)
             if proc and not proc._is_postmaster_process():
@@ -153,12 +168,15 @@ class PostmasterProcess(psutil.Process):
                 env['PG_GRANDPARENT_PID'] = str(proc.pid)
         except psutil.NoSuchProcess:
             pass
-
-        proc = call_self(['pg_ctl_start', pgcommand, '-D', data_dir,
-                          '--config-file={}'.format(conf)] + options, close_fds=True,
-                         preexec_fn=os.setsid, stdout=subprocess.PIPE, env=env)
-        pid = int(proc.stdout.readline().strip())
-        proc.wait()
+        cmdline = [pgcommand, '-D', data_dir, '--config-file={}'.format(conf)] + options
+        logger.debug("Starting postgres: %s", " ".join(cmdline))
+        parent_conn, child_conn = multiprocessing.Pipe(False)
+        proc = multiprocessing.Process(target=pg_ctl_start, args=(child_conn, cmdline, env))
+        proc.start()
+        pid = parent_conn.recv()
+        proc.join()
+        if pid is None:
+            return
         logger.info('postmaster pid=%s', pid)
 
         # TODO: In an extremely unlikely case, the process could have exited and the pid reassigned. The start

patroni/scripts/wale_restore.py

@@ -224,13 +224,12 @@ class WALERestore(object):
                             lsn_name = 'location'
                         con.autocommit = True
                         with con.cursor() as cur:
-                            cur.execute("""SELECT CASE WHEN pg_is_in_recovery()
-                                                       THEN GREATEST(
-                                                                pg_{0}_{1}_diff(COALESCE(
-                                                                  pg_last_{0}_receive_{1}(), '0/0'), %s)::bigint,
-                                                                pg_{0}_{1}_diff(pg_last_{0}_replay_{1}(), %s)::bigint)
-                                                       ELSE pg_{0}_{1}_diff(pg_current_{0}_{1}(), %s)::bigint
-                                                   END""".format(wal_name, lsn_name),
+                            cur.execute(("SELECT CASE WHEN pg_catalog.pg_is_in_recovery()"
+                                         " THEN GREATEST(pg_catalog.pg_{0}_{1}_diff(COALESCE("
+                                         "pg_last_{0}_receive_{1}(), '0/0'), %s)::bigint, "
+                                         "pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), %s)::bigint)"
+                                         " ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), %s)::bigint"
+                                         " END").format(wal_name, lsn_name),
                                         (backup_start_lsn, backup_start_lsn, backup_start_lsn))
 
                             diff_in_bytes = int(cur.fetchone()[0])

patroni/version.py

@@ -1 +1 @@
-__version__ = '1.4.5'
+__version__ = '1.5.6'

patroni/watchdog/linux.py

@@ -1,6 +1,5 @@
 import collections
 import ctypes
-import fcntl
 import os
 import platform
 from patroni.watchdog.base import WatchdogBase, WatchdogError
@@ -162,7 +161,9 @@ class LinuxWatchdogDevice(WatchdogBase):
         Raises OSError or IOError (Python 2) when the ioctl fails."""
         if self._fd is None:
             raise WatchdogError("Watchdog device is closed")
-        fcntl.ioctl(self._fd, func, arg, True)
+        if os.name != 'nt':
+            import fcntl
+            fcntl.ioctl(self._fd, func, arg, True)
 
     def get_support(self):
         if self._support_cache is None:

postgres0.yml

@@ -11,6 +11,11 @@ restapi:
 #    username: username
 #    password: password
 
+# ctl:
+#   insecure: false # Allow connections to SSL sites without certs
+#   certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem
+#   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
+
 etcd:
   host: 127.0.0.1:2379
 
@@ -24,6 +29,10 @@ bootstrap:
     maximum_lag_on_failover: 1048576
 #    master_start_timeout: 300
 #    synchronous_mode: false
+    #standby_cluster:
+      #host: 127.0.0.1
+      #port: 1111
+      #primary_slot_name: patroni
     postgresql:
       use_pg_rewind: true
 #      use_slots: true

postgres1.yml

@@ -11,6 +11,11 @@ restapi:
 #    username: username
 #    password: password
 
+# ctl:
+#   insecure: false # Allow connections to SSL sites without certs
+#   certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem
+#   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
+
 etcd:
   host: 127.0.0.1:2379
 

postgres2.yml

@@ -11,6 +11,11 @@ restapi:
     username: username
     password: password
 
+# ctl:
+#   insecure: false # Allow connections to SSL sites without certs
+#   certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem
+#   cacert: /etc/ssl/certs/ssl-cacert-snakeoil.pem
+
 etcd:
   host: 127.0.0.1:2379
 

requirements.txt

@@ -11,6 +11,6 @@ click>=4.1
 prettytable>=0.7
 tzlocal
 python-dateutil
-psutil
+psutil>=2.0.0
 cdiff
 kubernetes>=2.0.0,<=7.0.0,!=4.0.*,!=5.0.*

setup.py

@@ -32,9 +32,10 @@ VERSION = read_version(MAIN_PACKAGE)
 DESCRIPTION = 'PostgreSQL High-Available orchestrator and CLI'
 LICENSE = 'The MIT License'
 URL = 'https://github.com/zalando/patroni'
-AUTHOR = 'Alexander Kukushkin, Oleksii Kliukin, Feike Steenbergen'
-AUTHOR_EMAIL = '[email protected], [email protected], [email protected]'
-KEYWORDS = 'etcd governor patroni postgresql postgres ha haproxy confd zookeeper exhibitor consul streaming replication'
+AUTHOR = 'Alexander Kukushkin, Dmitrii Dolgov, Oleksii Kliukin'
+AUTHOR_EMAIL = '[email protected], [email protected], [email protected]'
+KEYWORDS = 'etcd governor patroni postgresql postgres ha haproxy confd' +\
+    ' zookeeper exhibitor consul streaming replication kubernetes k8s'
 
 COVERAGE_XML = True
 COVERAGE_HTML = False
@@ -43,14 +44,18 @@ JUNIT_XML = True
 # Add here all kinds of additional classifiers as defined under
 # https://pypi.python.org/pypi?%3Aaction=list_classifiers
 CLASSIFIERS = [
-    'Development Status :: 4 - Beta',
+    'Development Status :: 5 - Production/Stable',
     'Environment :: Console',
     'Intended Audience :: Developers',
     'Intended Audience :: System Administrators',
     'License :: OSI Approved :: MIT License',
+    'Operating System :: MacOS',
     'Operating System :: POSIX :: Linux',
+    'Operating System :: POSIX :: BSD :: FreeBSD',
+    'Operating System :: Microsoft :: Windows',
     'Programming Language :: Python',
     'Programming Language :: Python :: 2.7',
+    'Programming Language :: Python :: 3',
     'Programming Language :: Python :: 3.4',
     'Programming Language :: Python :: 3.5',
     'Programming Language :: Python :: 3.6',
@@ -102,6 +107,8 @@ class PyTest(TestCommand):
         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'):
+            os.environ['SYSTEMROOT'] = '/'
         errno = pytest.main(**params)
         sys.exit(errno)
 

tests/test_api.py

@@ -73,7 +73,7 @@ class MockHa(object):
 
     @staticmethod
     def fetch_nodes_statuses(members):
-        return [_MemberStatus(None, True, None, None, {}, False)]
+        return [_MemberStatus(None, True, None, 0, None, {}, False)]
 
     @staticmethod
     def schedule_future_restart(data):
@@ -95,6 +95,10 @@ class MockHa(object):
     def is_paused():
         return True
 
+    @staticmethod
+    def is_standby_cluster():
+        return False
+
 
 class MockPatroni(object):
 
@@ -155,6 +159,7 @@ class TestRestApiHandler(unittest.TestCase):
         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 = ''
             MockRestApiServer(RestApiHandler, 'GET /asynchronous')
         MockPatroni.ha.is_leader = Mock(return_value=True)
         MockRestApiServer(RestApiHandler, 'GET /replica')
@@ -166,6 +171,8 @@ class TestRestApiHandler(unittest.TestCase):
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /master'))
         with patch.object(RestApiServer, 'query', Mock(return_value=[('', 1, '', '', '', '', False, '')])):
             self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /patroni'))
+        with patch.object(MockHa, 'is_standby_cluster', Mock(return_value=True)):
+            MockRestApiServer(RestApiHandler, 'GET /standby_leader')
 
     def test_do_OPTIONS(self):
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'OPTIONS / HTTP/1.0'))
@@ -394,3 +401,9 @@ class TestRestApiServer(unittest.TestCase):
         self.assertRaises(ValueError, srv.reload_config, bad_config)
         self.assertRaises(ValueError, srv.reload_config, {})
         srv.reload_config({'listen': '127.0.0.2:8008'})
+
+    def test_handle_error(self):
+        try:
+            raise Exception()
+        except Exception:
+            self.assertIsNone(MockRestApiServer.handle_error(None, ('127.0.0.1', 55555)))

tests/test_callback_executor.py

@@ -17,6 +17,9 @@ class TestCallbackExecutor(unittest.TestCase):
 
         self.assertIsNone(ce.call([]))
 
+        mock_popen.return_value.kill.side_effect = OSError
+        self.assertRaises(Exception, ce.call, [])
+
         mock_popen.side_effect = Exception
         ce = CallbackExecutor()
         ce._callback_event.wait = Mock(side_effect=[None, Exception])

tests/test_config.py

@@ -1,6 +1,6 @@
 import os
-import unittest
 import sys
+import unittest
 
 from mock import MagicMock, Mock, patch
 from patroni.config import Config
@@ -23,13 +23,15 @@ class TestConfig(unittest.TestCase):
     def test_set_dynamic_configuration(self):
         with patch.object(Config, '_build_effective_configuration', Mock(side_effect=Exception)):
             self.assertIsNone(self.config.set_dynamic_configuration({'foo': 'bar'}))
-        self.assertTrue(self.config.set_dynamic_configuration({'synchronous_mode': True}))
+        self.assertTrue(self.config.set_dynamic_configuration({'synchronous_mode': True, 'standby_cluster': {}}))
 
     def test_reload_local_configuration(self):
         os.environ.update({
             'PATRONI_NAME': 'postgres0',
             'PATRONI_NAMESPACE': '/patroni/',
             'PATRONI_SCOPE': 'batman2',
+            'PATRONI_LOGLEVEL': 'ERROR',
+            'PATRONI_LOG_LOGGERS': 'patroni.postmaster: WARNING, urllib3: DEBUG',
             'PATRONI_RESTAPI_USERNAME': 'username',
             'PATRONI_RESTAPI_PASSWORD': 'password',
             'PATRONI_RESTAPI_LISTEN': '0.0.0.0:8008',
@@ -49,7 +51,8 @@ class TestConfig(unittest.TestCase):
             'PATRONI_ETCD_CERT': '/cert',
             'PATRONI_ETCD_KEY': '/key',
             'PATRONI_CONSUL_HOST': '127.0.0.1:8500',
-            'PATRONI_KUBERNETES_LABELS': 'a:b:c',
+            'PATRONI_CONSUL_REGISTER_SERVICE': 'on',
+            'PATRONI_KUBERNETES_LABELS': 'a: b: c',
             'PATRONI_KUBERNETES_SCOPE_LABEL': 'a',
             'PATRONI_KUBERNETES_PORTS': '[{"name": "postgresql"}]',
             'PATRONI_ZOOKEEPER_HOSTS': "'host1:2181','host2:2181'",
@@ -70,12 +73,13 @@ class TestConfig(unittest.TestCase):
                 self.assertRaises(Exception, config.reload_local_configuration, True)
             self.assertTrue(config.reload_local_configuration(True))
             self.assertTrue(config.reload_local_configuration())
+            self.assertIsNone(config.reload_local_configuration())
 
     @patch('tempfile.mkstemp', Mock(return_value=[3000, 'blabla']))
     @patch('os.path.exists', Mock(return_value=True))
     @patch('os.remove', Mock(side_effect=IOError))
     @patch('os.close', Mock(side_effect=IOError))
-    @patch('os.rename', Mock(return_value=None))
+    @patch('shutil.move', Mock(return_value=None))
     @patch('json.dump', Mock())
     def test_save_cache(self):
         self.config.set_dynamic_configuration({'ttl': 30, 'postgresql': {'foo': 'bar'}})
@@ -83,3 +87,15 @@ class TestConfig(unittest.TestCase):
             self.config.save_cache()
         with patch('os.fdopen', MagicMock()):
             self.config.save_cache()
+
+    def test_standby_cluster_parameters(self):
+        dynamic_configuration = {
+            'standby_cluster': {
+                'create_replica_methods': ['wal_e', 'basebackup'],
+                'host': 'localhost',
+                'port': 5432
+            }
+        }
+        self.config.set_dynamic_configuration(dynamic_configuration)
+        for name, value in dynamic_configuration['standby_cluster'].items():
+            self.assertEqual(self.config['standby_cluster'][name], value)

tests/test_consul.py

@@ -4,7 +4,7 @@ import unittest
 from consul import ConsulException, NotFound
 from mock import Mock, patch
 from patroni.dcs.consul import AbstractDCS, Cluster, Consul, ConsulInternalError, \
-                                ConsulError, HTTPClient, InvalidSessionTTL
+                                ConsulError, HTTPClient, InvalidSessionTTL, InvalidSession
 from test_etcd import SleepException
 
 
@@ -52,6 +52,8 @@ class TestHTTPClient(unittest.TestCase):
         self.assertRaises(ConsulInternalError, self.client.get, Mock(), '')
         self.client.http.request.return_value.data = b"Invalid Session TTL '3000000000', must be between [10s=24h0m0s]"
         self.assertRaises(InvalidSessionTTL, self.client.get, Mock(), '')
+        self.client.http.request.return_value.data = b"invalid session '16492f43-c2d6-5307-432f-e32d6f7bcbd0'"
+        self.assertRaises(InvalidSession, self.client.get, Mock(), '')
 
     def test_unknown_method(self):
         try:
@@ -62,7 +64,7 @@ class TestHTTPClient(unittest.TestCase):
 
     def test_put(self):
         self.client.put(Mock(), '/v1/session/create')
-        self.client.put(Mock(), '/v1/session/create', data='{"foo": "bar"}')
+        self.client.put(Mock(), '/v1/session/create', params=[], data='{"foo": "bar"}')
 
 
 @patch.object(consul.Consul.KV, 'get', kv_get)
@@ -74,12 +76,14 @@ class TestConsul(unittest.TestCase):
     @patch.object(consul.Consul.KV, 'delete', Mock())
     def setUp(self):
         Consul({'ttl': 30, 'scope': 't', 'name': 'p', 'url': 'https://l:1', 'retry_timeout': 10,
-                'verify': 'on', 'key': 'foo', 'cert': 'bar', 'cacert': 'buz', 'token': 'asd', 'dc': 'dc1'})
-        Consul({'ttl': 30, 'scope': 't', 'name': 'p', 'url': 'https://l:1', 'retry_timeout': 10,
-                'verify': 'on', 'cert': 'bar', 'cacert': 'buz'})
-        self.c = Consul({'ttl': 30, 'scope': 'test', 'name': 'postgresql1', 'host': 'localhost:1', 'retry_timeout': 10})
+                'verify': 'on', 'key': 'foo', 'cert': 'bar', 'cacert': 'buz', 'token': 'asd', 'dc': 'dc1',
+                'register_service': True})
+        Consul({'ttl': 30, 'scope': 't_', 'name': 'p', 'url': 'https://l:1', 'retry_timeout': 10,
+                'verify': 'on', 'cert': 'bar', 'cacert': 'buz', 'register_service': True})
+        self.c = Consul({'ttl': 30, 'scope': 'test', 'name': 'postgresql1', 'host': 'localhost:1', 'retry_timeout': 10,
+                         'register_service': True})
         self.c._base_path = '/service/good'
-        self.c._load_cluster()
+        self.c.get_cluster()
 
     @patch('time.sleep', Mock(side_effect=SleepException))
     @patch.object(consul.Consul.Session, 'create', Mock(side_effect=ConsulException))
@@ -108,17 +112,18 @@ class TestConsul(unittest.TestCase):
         self.c._session = 'fd4f44fe-2cac-bba5-a60b-304b51ff39b8'
         self.assertIsInstance(self.c.get_cluster(), Cluster)
 
-    @patch.object(consul.Consul.KV, 'delete', Mock(side_effect=[ConsulException, True, True]))
-    @patch.object(consul.Consul.KV, 'put', Mock(side_effect=[True, ConsulException]))
+    @patch.object(consul.Consul.KV, 'delete', Mock(side_effect=[ConsulException, True, True, True]))
+    @patch.object(consul.Consul.KV, 'put', Mock(side_effect=[True, ConsulException, InvalidSession]))
     def test_touch_member(self):
-        self.c.refresh_session = Mock(return_value=True)
-        self.c.touch_member({'balbla': 'blabla'})
-        self.c.touch_member({'balbla': 'blabla'})
-        self.c.touch_member({'balbla': 'blabla'})
         self.c.refresh_session = Mock(return_value=False)
-        self.c.touch_member({'balbla': 'blabla'})
+        self.c.touch_member({'conn_url': 'postgres://replicator:[email protected]:5433/postgres',
+                             'api_url': 'http://127.0.0.1:8009/patroni'})
+        self.c._register_service = True
+        self.c.refresh_session = Mock(return_value=True)
+        for _ in range(0, 4):
+            self.c.touch_member({'balbla': 'blabla'})
 
-    @patch.object(consul.Consul.KV, 'put', Mock(return_value=False))
+    @patch.object(consul.Consul.KV, 'put', Mock(side_effect=InvalidSession))
     def test_take_leader(self):
         self.c.set_ttl(20)
         self.c.refresh_session = Mock()
@@ -176,3 +181,19 @@ class TestConsul(unittest.TestCase):
     @patch.object(consul.Consul.KV, 'put', Mock(return_value=True))
     def test_set_history_value(self):
         self.assertTrue(self.c.set_history_value('{}'))
+
+    @patch.object(consul.Consul.Agent.Service, 'register', Mock(side_effect=(False, True)))
+    @patch.object(consul.Consul.Agent.Service, 'deregister', Mock(return_value=True))
+    def test_update_service(self):
+        d = {'role': 'replica', 'api_url': 'http://a/t', 'conn_url': 'pg://c:1', 'state': 'running'}
+        self.assertIsNone(self.c.update_service({}, {}))
+        self.assertFalse(self.c.update_service({}, d))
+        self.assertTrue(self.c.update_service(d, d))
+        self.assertIsNone(self.c.update_service(d, d))
+        d['state'] = 'stopped'
+        self.assertTrue(self.c.update_service(d, d, force=True))
+        d['state'] = 'unknown'
+        self.assertIsNone(self.c.update_service({}, d))
+        d['state'] = 'running'
+        d['role'] = 'bla'
+        self.assertIsNone(self.c.update_service({}, d))

tests/test_ctl.py

@@ -192,24 +192,24 @@ class TestCtl(unittest.TestCase):
 
     def test_query_member(self):
         with patch('patroni.ctl.get_cursor', Mock(return_value=MockConnect().cursor())):
-            rows = query_member(None, None, None, 'master', 'SELECT pg_is_in_recovery()', {})
+            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_is_in_recovery()', {})
-            self.assertEquals(rows, (None, None))
+            rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
+            self.assertEqual(rows, (None, None))
 
             with patch('test_postgresql.MockCursor.execute', Mock(side_effect=OperationalError('bla'))):
-                rows = query_member(None, None, None, 'replica', 'SELECT pg_is_in_recovery()', {})
+                rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
 
         with patch('patroni.ctl.get_cursor', Mock(return_value=None)):
-            rows = query_member(None, None, None, None, 'SELECT pg_is_in_recovery()', {})
+            rows = query_member(None, None, None, None, 'SELECT pg_catalog.pg_is_in_recovery()', {})
             self.assertTrue('No connection to' in str(rows))
 
-            rows = query_member(None, None, None, 'replica', 'SELECT pg_is_in_recovery()', {})
+            rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
             self.assertTrue('No connection to' in str(rows))
 
         with patch('patroni.ctl.get_cursor', Mock(side_effect=OperationalError('bla'))):
-            rows = query_member(None, None, None, 'replica', 'SELECT pg_is_in_recovery()', {})
+            rows = query_member(None, None, None, 'replica', 'SELECT pg_catalog.pg_is_in_recovery()', {})
 
     @patch('patroni.ctl.get_dcs')
     def test_dsn(self, mock_get_dcs):
@@ -225,6 +225,22 @@ class TestCtl(unittest.TestCase):
         result = self.runner.invoke(ctl, ['dsn', 'alpha', '--member', 'dummy'])
         assert result.exit_code == 1
 
+    @patch('requests.post')
+    @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
+
+        result = self.runner.invoke(ctl, ['reload', 'alpha'], input='y')
+        assert 'Failed: reload for member' in result.output
+
+        mock_post.return_value.status_code = 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
+        result = self.runner.invoke(ctl, ['reload', 'alpha'], input='y')
+        assert 'Reload request received for member' in result.output
+
     @patch('requests.post', requests_get)
     @patch('patroni.ctl.get_dcs')
     def test_restart_reinit(self, mock_get_dcs):
@@ -328,8 +344,14 @@ class TestCtl(unittest.TestCase):
         assert result.exit_code == 0
 
     @patch('requests.post', Mock(side_effect=requests.exceptions.ConnectionError('foo')))
-    def test_request_patroni(self):
+    @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):
@@ -342,20 +364,20 @@ class TestCtl(unittest.TestCase):
         self.assertIsNone(get_any_member(get_cluster_initialized_without_leader(), role='master'))
 
         m = get_any_member(get_cluster_initialized_with_leader(), role='master')
-        self.assertEquals(m.name, 'leader')
+        self.assertEqual(m.name, 'leader')
 
     def test_get_all_members(self):
-        self.assertEquals(list(get_all_members(get_cluster_initialized_without_leader(), role='master')), [])
+        self.assertEqual(list(get_all_members(get_cluster_initialized_without_leader(), role='master')), [])
 
         r = list(get_all_members(get_cluster_initialized_with_leader(), role='master'))
-        self.assertEquals(len(r), 1)
-        self.assertEquals(r[0].name, 'leader')
+        self.assertEqual(len(r), 1)
+        self.assertEqual(r[0].name, 'leader')
 
         r = list(get_all_members(get_cluster_initialized_with_leader(), role='replica'))
-        self.assertEquals(len(r), 1)
-        self.assertEquals(r[0].name, 'other')
+        self.assertEqual(len(r), 1)
+        self.assertEqual(r[0].name, 'other')
 
-        self.assertEquals(len(list(get_all_members(get_cluster_initialized_without_leader(), role='replica'))), 2)
+        self.assertEqual(len(list(get_all_members(get_cluster_initialized_without_leader(), role='replica'))), 2)
 
     @patch('patroni.ctl.get_dcs')
     def test_members(self, mock_get_dcs):
@@ -477,23 +499,23 @@ class TestCtl(unittest.TestCase):
         after_editing, changed_config = apply_config_changes(before_editing, config,
                                                              ["postgresql.parameters.work_mem = 5MB",
                                                               "ttl=15", "postgresql.use_pg_rewind=off", 'a.b=c'])
-        self.assertEquals(changed_config, {"a": {"b": "c"}, "postgresql": {"parameters": {"work_mem": "5MB"},
-                                                                           "use_pg_rewind": False}, "ttl": 15})
+        self.assertEqual(changed_config, {"a": {"b": "c"}, "postgresql": {"parameters": {"work_mem": "5MB"},
+                                                                          "use_pg_rewind": False}, "ttl": 15})
 
         # postgresql.parameters namespace is flattened
         after_editing, changed_config = apply_config_changes(before_editing, config,
                                                              ["postgresql.parameters.work_mem.sub = x"])
-        self.assertEquals(changed_config, {"postgresql": {"parameters": {"work_mem": "4MB", "work_mem.sub": "x"},
-                                                          "use_pg_rewind": True}, "ttl": 30})
+        self.assertEqual(changed_config, {"postgresql": {"parameters": {"work_mem": "4MB", "work_mem.sub": "x"},
+                                                         "use_pg_rewind": True}, "ttl": 30})
 
         # Setting to null deletes
         after_editing, changed_config = apply_config_changes(before_editing, config,
                                                              ["postgresql.parameters.work_mem=null"])
-        self.assertEquals(changed_config, {"postgresql": {"use_pg_rewind": True}, "ttl": 30})
+        self.assertEqual(changed_config, {"postgresql": {"use_pg_rewind": True}, "ttl": 30})
         after_editing, changed_config = apply_config_changes(before_editing, config,
                                                              ["postgresql.use_pg_rewind=null",
                                                               "postgresql.parameters.work_mem=null"])
-        self.assertEquals(changed_config, {"ttl": 30})
+        self.assertEqual(changed_config, {"ttl": 30})
 
         self.assertRaises(PatroniCtlException, apply_config_changes, before_editing, config, ['a'])
 
@@ -511,7 +533,8 @@ class TestCtl(unittest.TestCase):
         show_diff(b"foo:\n  bar: \xc3\xb6\xc3\xb6\n".decode('utf-8'),
                   b"foo:\n  bar: \xc3\xbc\xc3\xbc\n".decode('utf-8'))
 
-    def test_invoke_editor(self):
+    @patch('subprocess.call', return_value=1)
+    def test_invoke_editor(self, mock_subprocess_call):
         for e in ('', 'false'):
             os.environ['EDITOR'] = e
             self.assertRaises(PatroniCtlException, invoke_editor, 'foo: bar\n', 'test')
@@ -526,13 +549,14 @@ class TestCtl(unittest.TestCase):
     def test_edit_config(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
+        mock_get_dcs.return_value.set_config_value = Mock(return_value=False)
         os.environ['EDITOR'] = 'true'
         self.runner.invoke(ctl, ['edit-config', 'dummy'])
         self.runner.invoke(ctl, ['edit-config', 'dummy', '-s', 'foo=bar'])
         self.runner.invoke(ctl, ['edit-config', 'dummy', '--replace', 'postgres0.yml'])
         self.runner.invoke(ctl, ['edit-config', 'dummy', '--apply', '-'], input='foo: bar')
         self.runner.invoke(ctl, ['edit-config', 'dummy', '--force', '--apply', '-'], input='foo: bar')
-        mock_get_dcs.return_value.set_config_value = Mock(return_value=True)
+        mock_get_dcs.return_value.set_config_value.return_value = True
         self.runner.invoke(ctl, ['edit-config', 'dummy', '--force', '--apply', '-'], input='foo: bar')
 
     @patch('patroni.ctl.get_dcs')
@@ -550,5 +574,5 @@ class TestCtl(unittest.TestCase):
             assert 'failed to get version' in result.output
 
     def test_format_pg_version(self):
-        self.assertEquals(format_pg_version(100001), '10.1')
-        self.assertEquals(format_pg_version(90605), '9.6.5')
+        self.assertEqual(format_pg_version(100001), '10.1')
+        self.assertEqual(format_pg_version(90605), '9.6.5')

tests/test_etcd.py

@@ -148,13 +148,14 @@ def socket_getaddrinfo(*args):
 def http_request(method, url, **kwargs):
     if url == 'http://localhost:2379/timeout':
         raise ReadTimeoutError(None, None, None)
+    ret = MockResponse()
     if url == 'http://localhost:2379/v2/machines':
-        ret = MockResponse()
         ret.content = 'http://localhost:2379,http://localhost:4001'
-        return ret
-    if url == 'http://localhost:2379/':
-        return MockResponse()
-    raise socket.error
+    elif url == 'http://localhost:4001/v2/machines':
+        ret.content = ''
+    elif url != 'http://localhost:2379/':
+        raise socket.error
+    return ret
 
 
 class TestDnsCachingResolver(unittest.TestCase):
@@ -209,14 +210,14 @@ class TestClient(unittest.TestCase):
         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, '/', '')
-        self.client._update_machines_cache = True
         with patch.object(Client, '_load_machines_cache', Mock(side_effect=etcd.EtcdException)):
             self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', 'GET')
 
     def test_get_srv_record(self):
-        self.assertEquals(self.client.get_srv_record('_etcd-server._tcp.blabla'), [])
-        self.assertEquals(self.client.get_srv_record('_etcd-server._tcp.exception'), [])
+        self.assertEqual(self.client.get_srv_record('_etcd-server._tcp.blabla'), [])
+        self.assertEqual(self.client.get_srv_record('_etcd-server._tcp.exception'), [])
 
     def test__get_machines_cache_from_srv(self):
         self.client._get_machines_cache_from_srv('foobar')
@@ -259,21 +260,22 @@ class TestEtcd(unittest.TestCase):
                               'host': 'localhost:2379', 'scope': 'test', 'name': 'foo'})
 
     def test_base_path(self):
-        self.assertEquals(self.etcd._base_path, '/patroni/test')
+        self.assertEqual(self.etcd._base_path, '/patroni/test')
 
     @patch('dns.resolver.query', dns_query)
     def test_get_etcd_client(self):
-        with patch.object(Client, 'machines') as mock_machines:
+        with patch('time.sleep', Mock(side_effect=SleepException)),\
+                patch.object(Client, 'machines') as mock_machines:
             mock_machines.__get__ = Mock(side_effect=etcd.EtcdException)
-            with patch('time.sleep', Mock(side_effect=SleepException)):
-                self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                                  {'discovery_srv': 'test', 'retry_timeout': 10, 'cacert': '1', 'key': '1', 'cert': 1})
-                self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                                  {'url': 'https://test:2379', 'retry_timeout': 10})
-                self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                                  {'proxy': 'https://user:password@test:2379', 'retry_timeout': 10})
-                self.assertRaises(SleepException, self.etcd.get_etcd_client,
-                                  {'hosts': 'foo:4001,bar', 'retry_timeout': 10})
+            self.assertRaises(SleepException, self.etcd.get_etcd_client,
+                              {'discovery_srv': 'test', 'retry_timeout': 10, 'cacert': '1', 'key': '1', 'cert': 1})
+            self.assertRaises(SleepException, self.etcd.get_etcd_client,
+                              {'url': 'https://test:2379', 'retry_timeout': 10})
+            self.assertRaises(SleepException, self.etcd.get_etcd_client,
+                              {'hosts': 'foo:4001,bar', 'retry_timeout': 10})
+            mock_machines.__get__ = Mock(return_value=[])
+            self.assertRaises(SleepException, self.etcd.get_etcd_client,
+                              {'proxy': 'https://user:password@test:2379', 'retry_timeout': 10})
 
     def test_get_cluster(self):
         cluster = self.etcd.get_cluster()

tests/test_ha.py

@@ -2,6 +2,7 @@ import datetime
 import etcd
 import os
 import unittest
+import sys
 
 from mock import Mock, MagicMock, PropertyMock, patch
 from patroni.config import Config
@@ -26,16 +27,19 @@ def false(*args, **kwargs):
     return False
 
 
-def get_cluster(initialize, leader, members, failover, sync):
-    history = TimelineHistory(1, [(1, 67197376, 'no recovery target specified', datetime.datetime.now().isoformat())])
-    return Cluster(initialize, ClusterConfig(1, {1: 2}, 1), leader, 10, members, failover, sync, history)
+def get_cluster(initialize, leader, members, failover, sync, cluster_config=None):
+    t = datetime.datetime.now().isoformat()
+    history = TimelineHistory(1, '[[1,67197376,"no recovery target specified","' + t + '"]]',
+                              [(1, 67197376, 'no recovery target specified', t)])
+    cluster_config = cluster_config or ClusterConfig(1, {'check_timeline': True}, 1)
+    return Cluster(initialize, cluster_config, leader, 10, members, failover, sync, history)
 
 
-def get_cluster_not_initialized_without_leader():
-    return get_cluster(None, None, [], None, SyncState(None, None, None))
+def get_cluster_not_initialized_without_leader(cluster_config=None):
+    return get_cluster(None, None, [], None, SyncState(None, None, None), cluster_config)
 
 
-def get_cluster_initialized_without_leader(leader=False, failover=None, sync=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
@@ -47,24 +51,36 @@ def get_cluster_initialized_without_leader(leader=False, failover=None, sync=Non
                                  'scheduled_restart': {'schedule': "2100-01-01 10:53:07.560445+00:00",
                                                        'postgres_version': '99.0.0'}})
     syncstate = SyncState(0 if sync else None, sync and sync[0], sync and sync[1])
-    return get_cluster(SYSID, leader, [m1, m2], failover, syncstate)
+    return get_cluster(SYSID, leader, [m1, m2], failover, syncstate, cluster_config)
 
 
 def get_cluster_initialized_with_leader(failover=None, sync=None):
     return get_cluster_initialized_without_leader(leader=True, failover=failover, sync=sync)
 
 
-def get_cluster_initialized_with_only_leader(failover=None):
+def get_cluster_initialized_with_only_leader(failover=None, cluster_config=None):
     leader = get_cluster_initialized_without_leader(leader=True, failover=failover).leader
-    return get_cluster(True, leader, [leader], failover, None)
+    return get_cluster(True, leader, [leader], failover, None, cluster_config)
 
 
-def get_node_status(reachable=True, in_recovery=True, wal_position=10, nofailover=False, watchdog_failed=False):
+def get_standby_cluster_initialized_with_only_leader(failover=None, sync=None):
+    return get_cluster_initialized_with_only_leader(
+        cluster_config=ClusterConfig(1, {
+            "standby_cluster": {
+                "host": "localhost",
+                "port": 5432,
+                "primary_slot_name": "",
+            }}, 1)
+    )
+
+
+def get_node_status(reachable=True, in_recovery=True, timeline=2,
+                    wal_position=10, nofailover=False, watchdog_failed=False):
     def fetch_node_status(e):
         tags = {}
         if nofailover:
             tags['nofailover'] = True
-        return _MemberStatus(e, reachable, in_recovery, wal_position, tags, watchdog_failed)
+        return _MemberStatus(e, reachable, in_recovery, timeline, wal_position, tags, watchdog_failed)
     return fetch_node_status
 
 
@@ -97,7 +113,12 @@ zookeeper:
     hosts: [localhost]
     port: 8181
 """
+        # We rely on sys.argv in Config, so it's necessary to reset
+        # all the extra values that are coming from py.test
+        sys.argv = sys.argv[:1]
+
         self.config = Config()
+        self.config.set_dynamic_configuration({'maximum_lag_on_failover': 5})
         self.postgresql = p
         self.dcs = d
         self.api = Mock()
@@ -129,8 +150,10 @@ def run_async(self, func, args=()):
 @patch.object(Postgresql, 'write_recovery_conf', Mock())
 @patch.object(Postgresql, 'query', Mock())
 @patch.object(Postgresql, 'checkpoint', Mock())
-@patch.object(Postgresql, 'call_nowait', Mock())
 @patch.object(Postgresql, 'cancellable_subprocess_call', Mock(return_value=0))
+@patch.object(Postgresql, '_get_local_timeline_lsn_from_replication_connection', Mock(return_value=[2, 10]))
+@patch.object(Postgresql, 'get_master_timeline', Mock(return_value=2))
+@patch.object(Postgresql, 'restore_configuration_files', Mock())
 @patch.object(etcd.Client, 'write', etcd_write)
 @patch.object(etcd.Client, 'read', etcd_read)
 @patch.object(etcd.Client, 'delete', Mock(side_effect=etcd.EtcdException))
@@ -150,7 +173,6 @@ class TestHa(unittest.TestCase):
             mock_machines.__get__ = Mock(return_value=['http://remotehost:2379'])
             self.p = Postgresql({'name': 'postgresql0', 'scope': 'dummy', 'listen': '127.0.0.1:5432',
                                  'data_dir': 'data/postgresql0', 'retry_timeout': 10,
-                                 'maximum_lag_on_failover': 5,
                                  'authentication': {'superuser': {'username': 'foo', 'password': 'bar'},
                                                     'replication': {'username': '', 'password': ''}},
                                  'parameters': {'wal_level': 'hot_standby', 'max_replication_slots': 5, 'foo': 'bar',
@@ -175,16 +197,37 @@ class TestHa(unittest.TestCase):
         self.p.replica_cached_timeline = Mock(side_effect=Exception)
         self.ha.touch_member()
 
+    def test_is_leader(self):
+        self.assertFalse(self.ha.is_leader())
+
     def test_start_as_replica(self):
         self.p.is_healthy = false
-        self.assertEquals(self.ha.run_cycle(), 'starting as a secondary')
+        self.assertEqual(self.ha.run_cycle(), 'starting as a secondary')
+
+    @patch('patroni.dcs.etcd.Etcd.initialize', return_value=True)
+    def test_start_as_standby_leader(self, initialize):
+        self.p.data_directory_empty = true
+        self.ha.cluster = get_cluster_not_initialized_without_leader(cluster_config=ClusterConfig(0, {}, 0))
+        self.ha.cluster.is_unlocked = true
+        self.ha.patroni.config._dynamic_configuration = {"standby_cluster": {"port": 5432}}
+        self.assertEqual(self.ha.run_cycle(), 'trying to bootstrap a new standby leader')
+
+    @patch.object(Cluster, 'get_clone_member',
+                  Mock(return_value=Member(0, 'test', 1, {'api_url': 'http://127.0.0.1:8011/patroni',
+                                                          'conn_url': 'postgres://127.0.0.1:5432/postgres'})))
+    @patch.object(Postgresql, 'create_replica', Mock(return_value=0))
+    def test_start_as_cascade_replica_in_standby_cluster(self):
+        self.p.data_directory_empty = true
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.ha.cluster.is_unlocked = false
+        self.assertEqual(self.ha.run_cycle(), "trying to bootstrap from replica 'test'")
 
     def test_recover_replica_failed(self):
         self.p.controldata = lambda: {'Database cluster state': 'in recovery', 'Database system identifier': SYSID}
         self.p.is_running = false
         self.p.follow = false
-        self.assertEquals(self.ha.run_cycle(), 'starting as a secondary')
-        self.assertEquals(self.ha.run_cycle(), 'failed to start postgres')
+        self.assertEqual(self.ha.run_cycle(), 'starting as a secondary')
+        self.assertEqual(self.ha.run_cycle(), 'failed to start postgres')
 
     def test_recover_former_master(self):
         self.p.follow = false
@@ -193,19 +236,27 @@ class TestHa(unittest.TestCase):
         self.p.set_role('master')
         self.p.controldata = lambda: {'Database cluster state': 'shut down', 'Database system identifier': SYSID}
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.run_cycle(), 'starting as readonly because i had the session lock')
+        self.assertEqual(self.ha.run_cycle(), 'starting as readonly because i had the session lock')
 
     @patch.object(Postgresql, 'fix_cluster_state', Mock())
     def test_crash_recovery(self):
         self.p.is_running = false
         self.p.controldata = lambda: {'Database cluster state': 'in production', 'Database system identifier': SYSID}
-        self.assertEquals(self.ha.run_cycle(), 'doing crash recovery in a single user mode')
+        self.assertEqual(self.ha.run_cycle(), 'doing crash recovery in a single user mode')
 
-    @patch.object(Postgresql, 'rewind_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'rewind_or_reinitialize_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'can_rewind', PropertyMock(return_value=True))
     def test_recover_with_rewind(self):
         self.p.is_running = false
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.run_cycle(), 'running pg_rewind from leader')
+        self.assertEqual(self.ha.run_cycle(), 'running pg_rewind from leader')
+
+    @patch.object(Postgresql, 'rewind_or_reinitialize_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'create_replica', Mock(return_value=1))
+    def test_recover_with_reinitialize(self):
+        self.p.is_running = false
+        self.ha.cluster = get_cluster_initialized_with_leader()
+        self.assertEqual(self.ha.run_cycle(), 'reinitializing due to diverged timelines')
 
     @patch('sys.exit', return_value=1)
     @patch('patroni.ha.Ha.sysid_valid', MagicMock(return_value=True))
@@ -220,129 +271,130 @@ class TestHa(unittest.TestCase):
         self.p.is_healthy = true
         self.ha.has_lock = true
         self.p.controldata = lambda: {'Database cluster state': 'in production', 'Database system identifier': SYSID}
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
 
     @patch('psycopg2.connect', psycopg2_connect)
     def test_acquire_lock_as_master(self):
-        self.assertEquals(self.ha.run_cycle(), 'acquired session lock as a leader')
+        self.assertEqual(self.ha.run_cycle(), 'acquired session lock as a leader')
 
     def test_promoted_by_acquiring_lock(self):
         self.ha.is_healthiest_node = true
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
 
     def test_long_promote(self):
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
         self.p.is_leader = false
         self.p.set_role('master')
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
 
     def test_demote_after_failing_to_obtain_lock(self):
         self.ha.acquire_lock = false
-        self.assertEquals(self.ha.run_cycle(), 'demoted self after trying and failing to obtain lock')
+        self.assertEqual(self.ha.run_cycle(), 'demoted self after trying and failing to obtain lock')
 
     def test_follow_new_leader_after_failing_to_obtain_lock(self):
         self.ha.is_healthiest_node = true
         self.ha.acquire_lock = false
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'following new leader after trying and failing to obtain lock')
+        self.assertEqual(self.ha.run_cycle(), 'following new leader after trying and failing to obtain lock')
 
     def test_demote_because_not_healthiest(self):
         self.ha.is_healthiest_node = false
-        self.assertEquals(self.ha.run_cycle(), 'demoting self because i am not the healthiest node')
+        self.assertEqual(self.ha.run_cycle(), 'demoting self because i am not the healthiest node')
 
     def test_follow_new_leader_because_not_healthiest(self):
         self.ha.is_healthiest_node = false
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
+        self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
 
     def test_promote_because_have_lock(self):
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader because i had the session lock')
 
     def test_promote_without_watchdog(self):
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
         self.p.is_leader = true
         with patch.object(Watchdog, 'activate', Mock(return_value=False)):
-            self.assertEquals(self.ha.run_cycle(), 'Demoting self because watchdog could not be activated')
+            self.assertEqual(self.ha.run_cycle(), 'Demoting self because watchdog could not be activated')
             self.p.is_leader = false
-            self.assertEquals(self.ha.run_cycle(), 'Not promoting self because watchdog could not be activated')
+            self.assertEqual(self.ha.run_cycle(), 'Not promoting self because watchdog could not be activated')
 
     def test_leader_with_lock(self):
-        self.ha.cluster = get_cluster_not_initialized_without_leader()
+        self.ha.cluster = get_cluster_initialized_with_leader()
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
 
     def test_demote_because_not_having_lock(self):
         self.ha.cluster.is_unlocked = false
         with patch.object(Watchdog, 'is_running', PropertyMock(return_value=True)):
-            self.assertEquals(self.ha.run_cycle(), 'demoting self because i do not have the lock and i was a leader')
+            self.assertEqual(self.ha.run_cycle(), 'demoting self because i do not have the lock and i was a leader')
 
     def test_demote_because_update_lock_failed(self):
         self.ha.cluster.is_unlocked = false
         self.ha.has_lock = true
         self.ha.update_lock = false
-        self.assertEquals(self.ha.run_cycle(), 'demoted self because failed to update leader lock in DCS')
+        self.assertEqual(self.ha.run_cycle(), 'demoted self because failed to update leader lock in DCS')
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'not promoting because failed to update leader lock in DCS')
+        self.assertEqual(self.ha.run_cycle(), 'not promoting because failed to update leader lock in DCS')
 
     def test_follow(self):
         self.ha.cluster.is_unlocked = false
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
         self.ha.patroni.replicatefrom = "foo"
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
 
     def test_follow_in_pause(self):
         self.ha.cluster.is_unlocked = false
         self.ha.is_paused = true
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: no action')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: no action')
 
-    @patch.object(Postgresql, 'rewind_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'rewind_or_reinitialize_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'can_rewind', PropertyMock(return_value=True))
     def test_follow_triggers_rewind(self):
         self.p.is_leader = false
         self.p.trigger_check_diverged_lsn()
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.run_cycle(), 'running pg_rewind from leader')
+        self.assertEqual(self.ha.run_cycle(), 'running pg_rewind from leader')
 
     def test_no_etcd_connection_master_demote(self):
         self.ha.load_cluster_from_dcs = Mock(side_effect=DCSError('Etcd is not responding properly'))
-        self.assertEquals(self.ha.run_cycle(), 'demoted self because DCS is not accessible and i was a leader')
+        self.assertEqual(self.ha.run_cycle(), 'demoted self because DCS is not accessible and i was a leader')
 
     @patch('time.sleep', Mock())
     def test_bootstrap_from_another_member(self):
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.bootstrap(), 'trying to bootstrap from replica \'other\'')
+        self.assertEqual(self.ha.bootstrap(), 'trying to bootstrap from replica \'other\'')
 
     def test_bootstrap_waiting_for_leader(self):
         self.ha.cluster = get_cluster_initialized_without_leader()
-        self.assertEquals(self.ha.bootstrap(), 'waiting for leader to bootstrap')
+        self.assertEqual(self.ha.bootstrap(), 'waiting for leader to bootstrap')
 
     def test_bootstrap_without_leader(self):
         self.ha.cluster = get_cluster_initialized_without_leader()
         self.p.can_create_replica_without_replication_connection = MagicMock(return_value=True)
-        self.assertEquals(self.ha.bootstrap(), 'trying to bootstrap (without leader)')
+        self.assertEqual(self.ha.bootstrap(), 'trying to bootstrap (without leader)')
 
     def test_bootstrap_initialize_lock_failed(self):
         self.ha.cluster = get_cluster_not_initialized_without_leader()
-        self.assertEquals(self.ha.bootstrap(), 'failed to acquire initialize lock')
+        self.assertEqual(self.ha.bootstrap(), 'failed to acquire initialize lock')
 
     def test_bootstrap_initialized_new_cluster(self):
         self.ha.cluster = get_cluster_not_initialized_without_leader()
         self.e.initialize = true
-        self.assertEquals(self.ha.bootstrap(), 'trying to bootstrap a new cluster')
+        self.assertEqual(self.ha.bootstrap(), 'trying to bootstrap a new cluster')
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'waiting for end of recovery after bootstrap')
+        self.assertEqual(self.ha.run_cycle(), 'waiting for end of recovery after bootstrap')
         self.p.is_leader = true
-        self.assertEquals(self.ha.run_cycle(), 'running post_bootstrap')
-        self.assertEquals(self.ha.run_cycle(), 'initialized a new cluster')
+        self.assertEqual(self.ha.run_cycle(), 'running post_bootstrap')
+        self.assertEqual(self.ha.run_cycle(), 'initialized a new cluster')
 
     def test_bootstrap_release_initialize_key_on_failure(self):
         self.ha.cluster = get_cluster_not_initialized_without_leader()
@@ -358,7 +410,7 @@ class TestHa(unittest.TestCase):
         self.p.is_running.return_value = MockPostmaster()
         self.p.is_leader = true
         with patch.object(Watchdog, 'activate', Mock(return_value=False)):
-            self.assertEquals(self.ha.post_bootstrap(), 'running post_bootstrap')
+            self.assertEqual(self.ha.post_bootstrap(), 'running post_bootstrap')
             self.assertRaises(PatroniException, self.ha.post_bootstrap)
 
     @patch('psycopg2.connect', psycopg2_connect)
@@ -375,35 +427,35 @@ class TestHa(unittest.TestCase):
 
     @patch('time.sleep', Mock())
     def test_restart(self):
-        self.assertEquals(self.ha.restart({}), (True, 'restarted successfully'))
+        self.assertEqual(self.ha.restart({}), (True, 'restarted successfully'))
         self.p.restart = Mock(return_value=None)
-        self.assertEquals(self.ha.restart({}), (False, 'postgres is still starting'))
+        self.assertEqual(self.ha.restart({}), (False, 'postgres is still starting'))
         self.p.restart = false
-        self.assertEquals(self.ha.restart({}), (False, 'restart failed'))
+        self.assertEqual(self.ha.restart({}), (False, 'restart failed'))
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.ha.reinitialize()
-        self.assertEquals(self.ha.restart({}), (False, 'reinitialize already in progress'))
+        self.assertEqual(self.ha.restart({}), (False, 'reinitialize already in progress'))
         with patch.object(self.ha, "restart_matches", return_value=False):
-            self.assertEquals(self.ha.restart({'foo': 'bar'}), (False, "restart conditions are not satisfied"))
+            self.assertEqual(self.ha.restart({'foo': 'bar'}), (False, "restart conditions are not satisfied"))
 
     @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.assertTrue(self.ha.restart_scheduled())
-            self.assertEquals(self.ha.run_cycle(), 'restart in progress')
+            self.assertEqual(self.ha.run_cycle(), 'restart in progress')
 
             self.ha.cluster = get_cluster_initialized_with_leader()
-            self.assertEquals(self.ha.run_cycle(), 'restart in progress')
+            self.assertEqual(self.ha.run_cycle(), 'restart in progress')
 
             self.ha.has_lock = true
-            self.assertEquals(self.ha.run_cycle(), 'updated leader lock during restart')
+            self.assertEqual(self.ha.run_cycle(), 'updated leader lock during restart')
 
             self.ha.update_lock = false
             self.p.set_role('master')
             with patch('patroni.async_executor.CriticalTask.cancel', Mock(return_value=False)):
                 with patch('patroni.postgresql.Postgresql.terminate_starting_postmaster') as mock_terminate:
-                    self.assertEquals(self.ha.run_cycle(), 'lost leader lock during restart')
+                    self.assertEqual(self.ha.run_cycle(), 'lost leader lock during restart')
                     mock_terminate.assert_called()
 
     @patch('requests.get', requests_get)
@@ -411,25 +463,27 @@ class TestHa(unittest.TestCase):
         self.ha.fetch_node_status = get_node_status()
         self.ha.has_lock = true
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', '', None))
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', 'blabla', None))
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         f = Failover(0, self.p.name, '', None)
         self.ha.cluster = get_cluster_initialized_with_leader(f)
-        self.assertEquals(self.ha.run_cycle(), 'manual failover: demoting myself')
-        self.p.rewind_needed_and_possible = true
-        self.assertEquals(self.ha.run_cycle(), 'manual failover: demoting myself')
+        self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
+        self.p.rewind_or_reinitialize_needed_and_possible = true
+        self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
         self.ha.fetch_node_status = get_node_status(nofailover=True)
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         self.ha.fetch_node_status = get_node_status(watchdog_failed=True)
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.ha.fetch_node_status = get_node_status(timeline=1)
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         self.ha.fetch_node_status = get_node_status(wal_position=1)
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
         # manual failover from the previous leader to us won't happen if we hold the nofailover flag
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, None))
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
 
         # Failover scheduled time must include timezone
         scheduled = datetime.datetime.now()
@@ -438,19 +492,19 @@ class TestHa(unittest.TestCase):
 
         scheduled = datetime.datetime.utcnow().replace(tzinfo=tzutc)
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
-        self.assertEquals('no action.  i am the leader with the lock', self.ha.run_cycle())
+        self.assertEqual('no action.  i am the leader with the lock', self.ha.run_cycle())
 
         scheduled = scheduled + datetime.timedelta(seconds=30)
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
-        self.assertEquals('no action.  i am the leader with the lock', self.ha.run_cycle())
+        self.assertEqual('no action.  i am the leader with the lock', self.ha.run_cycle())
 
         scheduled = scheduled + datetime.timedelta(seconds=-600)
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
-        self.assertEquals('no action.  i am the leader with the lock', self.ha.run_cycle())
+        self.assertEqual('no action.  i am the leader with the lock', self.ha.run_cycle())
 
         scheduled = None
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
-        self.assertEquals('no action.  i am the leader with the lock', self.ha.run_cycle())
+        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):
@@ -458,9 +512,9 @@ class TestHa(unittest.TestCase):
         self.ha.is_paused = true
         scheduled = datetime.datetime.now()
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, 'blabla', self.p.name, scheduled))
-        self.assertEquals('PAUSE: no action.  i am the leader with the lock', self.ha.run_cycle())
+        self.assertEqual('PAUSE: no action.  i am the leader with the lock', self.ha.run_cycle())
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, '', None))
-        self.assertEquals('PAUSE: no action.  i am the leader with the lock', self.ha.run_cycle())
+        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):
@@ -470,48 +524,48 @@ class TestHa(unittest.TestCase):
         self.ha.is_failover_possible = false
         self.ha.process_sync_replication = Mock()
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None), (self.p.name, None))
-        self.assertEquals('no action.  i am the leader with the lock', self.ha.run_cycle())
+        self.assertEqual('no action.  i am the leader with the lock', self.ha.run_cycle())
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, self.p.name, 'a', None), (self.p.name, 'a'))
         self.ha.is_failover_possible = true
-        self.assertEquals('manual failover: demoting myself', self.ha.run_cycle())
+        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))
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'leader', None))
         self.p.set_role('replica')
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
         self.ha.fetch_node_status = get_node_status()  # accessible, in_recovery
-        self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
+        self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, self.p.name, '', None))
-        self.assertEquals(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
+        self.assertEqual(self.ha.run_cycle(), 'following a different leader because i am not the healthiest node')
         self.ha.fetch_node_status = get_node_status(reachable=False)  # inaccessible, in_recovery
         self.p.set_role('replica')
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
         # set failover flag to True for all members of the cluster
         # this should elect the current member, as we are not going to call the API for it.
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None))
         self.ha.fetch_node_status = get_node_status(nofailover=True)  # accessible, in_recovery
         self.p.set_role('replica')
-        self.assertEquals(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to leader by acquiring session lock')
         # same as previous, but set the current member to nofailover. In no case it should be elected as a leader
         self.ha.patroni.nofailover = True
-        self.assertEquals(self.ha.run_cycle(), 'following a different leader because I am not allowed to promote')
+        self.assertEqual(self.ha.run_cycle(), 'following a different leader because I am not allowed to promote')
 
     def test_manual_failover_process_no_leader_in_pause(self):
         self.ha.is_paused = true
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, '', 'other', None))
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', '', None))
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: continue to run as master without lock')
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', 'blabla', None))
-        self.assertEquals('PAUSE: acquired session lock as a leader', self.ha.run_cycle())
+        self.assertEqual('PAUSE: acquired session lock as a leader', self.ha.run_cycle())
         self.p.is_leader = false
         self.p.set_role('replica')
         self.ha.cluster = get_cluster_initialized_without_leader(failover=Failover(0, 'leader', self.p.name, None))
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: promoted self to leader by acquiring session lock')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: promoted self to leader by acquiring session lock')
 
     def test_is_healthiest_node(self):
         self.ha.state_handler.is_leader = false
@@ -525,6 +579,7 @@ class TestHa(unittest.TestCase):
         self.ha.is_paused = true
         self.assertFalse(self.ha.is_healthiest_node())
 
+    @patch('requests.get', requests_get)
     def test__is_healthiest_node(self):
         self.assertTrue(self.ha._is_healthiest_node(self.ha.old_cluster.members))
         self.p.is_leader = false
@@ -536,6 +591,8 @@ class TestHa(unittest.TestCase):
         self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
         with patch('patroni.postgresql.Postgresql.timeline_wal_position', return_value=(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))
         self.ha.patroni.nofailover = True
         self.assertFalse(self.ha._is_healthiest_node(self.ha.old_cluster.members))
         self.ha.patroni.nofailover = False
@@ -592,7 +649,7 @@ class TestHa(unittest.TestCase):
     def test_scheduled_restart(self):
         self.ha.cluster = get_cluster_initialized_with_leader()
         with patch.object(self.ha, "evaluate_scheduled_restart", Mock(return_value="restart scheduled")):
-            self.assertEquals(self.ha.run_cycle(), "restart scheduled")
+            self.assertEqual(self.ha.run_cycle(), "restart scheduled")
 
     def test_restart_matches(self):
         self.p._role = 'replica'
@@ -609,29 +666,82 @@ class TestHa(unittest.TestCase):
         self.ha.is_paused = true
         self.p.name = 'leader'
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running as master')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running as master')
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: waiting to become master after promote...')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: waiting to become master after promote...')
+
+    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.check_recovery_conf = true
+        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')
+
+    def test_process_healthy_standby_cluster_as_cascade_replica(self):
+        self.p.is_leader = false
+        self.p.name = 'replica'
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a standby leader')
+        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'
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.ha.cluster.is_unlocked = true
+        self.ha.sysid_valid = true
+        self.p._sysid = True
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to a standby leader by acquiring session lock')
+
+    @patch.object(Postgresql, 'rewind_or_reinitialize_needed_and_possible', Mock(return_value=True))
+    @patch.object(Postgresql, 'can_rewind', PropertyMock(return_value=True))
+    def test_process_unhealthy_standby_cluster_as_cascade_replica(self):
+        self.p.is_leader = false
+        self.p.name = 'replica'
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.ha.is_unlocked = true
+        self.assertTrue(self.ha.run_cycle().startswith('running pg_rewind from remote_master:'))
+
+    def test_recover_unhealthy_leader_in_standby_cluster(self):
+        self.p.is_leader = false
+        self.p.name = 'leader'
+        self.p.is_running = false
+        self.p.follow = false
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.assertEqual(self.ha.run_cycle(), 'starting as a standby leader because i had the session lock')
+
+    def test_recover_unhealthy_unlocked_standby_cluster(self):
+        self.p.is_leader = false
+        self.p.name = 'leader'
+        self.p.is_running = false
+        self.p.follow = false
+        self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
+        self.ha.cluster.is_unlocked = true
+        self.ha.has_lock = false
+        self.assertEqual(self.ha.run_cycle(), 'trying to follow a remote master because standby cluster is unhealthy')
 
     def test_failed_to_update_lock_in_pause(self):
         self.ha.update_lock = false
         self.ha.is_paused = true
         self.p.name = 'leader'
         self.ha.cluster = get_cluster_initialized_with_leader()
-        self.assertEquals(self.ha.run_cycle(),
-                          'PAUSE: continue to run as master after failing to update leader lock in DCS')
+        self.assertEqual(self.ha.run_cycle(),
+                         'PAUSE: continue to run as master after failing to update leader lock in DCS')
 
     def test_postgres_unhealthy_in_pause(self):
         self.ha.is_paused = true
         self.p.is_healthy = false
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: postgres is not running')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: postgres is not running')
         self.ha.has_lock = true
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: removed leader lock because postgres is not running')
 
     def test_no_etcd_connection_in_pause(self):
         self.ha.is_paused = true
         self.ha.load_cluster_from_dcs = Mock(side_effect=DCSError('Etcd is not responding properly'))
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: DCS is not accessible')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: DCS is not accessible')
 
     @patch('patroni.ha.Ha.update_lock', return_value=True)
     @patch('patroni.ha.Ha.demote')
@@ -647,26 +757,26 @@ class TestHa(unittest.TestCase):
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.p.check_for_startup = true
         self.p.time_in_state = lambda: 30
-        self.assertEquals(self.ha.run_cycle(), 'PostgreSQL is still starting up, 270 seconds until timeout')
+        self.assertEqual(self.ha.run_cycle(), 'PostgreSQL is still starting up, 270 seconds until timeout')
         check_calls([(update_lock, True), (demote, False)])
 
         self.p.time_in_state = lambda: 350
         self.ha.fetch_node_status = get_node_status(reachable=False)  # inaccessible, in_recovery
-        self.assertEquals(self.ha.run_cycle(),
-                          'master start has timed out, but continuing to wait because failover is not possible')
+        self.assertEqual(self.ha.run_cycle(),
+                         'master start has timed out, but continuing to wait because failover is not possible')
         check_calls([(update_lock, True), (demote, False)])
 
         self.ha.fetch_node_status = get_node_status()  # accessible, in_recovery
-        self.assertEquals(self.ha.run_cycle(), 'stopped PostgreSQL because of startup timeout')
+        self.assertEqual(self.ha.run_cycle(), 'stopped PostgreSQL because of startup timeout')
         check_calls([(update_lock, True), (demote, True)])
 
         update_lock.return_value = False
-        self.assertEquals(self.ha.run_cycle(), 'stopped PostgreSQL while starting up because leader key was lost')
+        self.assertEqual(self.ha.run_cycle(), 'stopped PostgreSQL while starting up because leader key was lost')
         check_calls([(update_lock, True), (demote, True)])
 
         self.ha.has_lock = false
         self.p.is_leader = false
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am a secondary and i am following a leader')
         check_calls([(update_lock, False), (demote, False)])
 
     def test_manual_failover_while_starting(self):
@@ -675,7 +785,7 @@ class TestHa(unittest.TestCase):
         f = Failover(0, self.p.name, '', None)
         self.ha.cluster = get_cluster_initialized_with_leader(f)
         self.ha.fetch_node_status = get_node_status()  # accessible, in_recovery
-        self.assertEquals(self.ha.run_cycle(), 'manual failover: demoting myself')
+        self.assertEqual(self.ha.run_cycle(), 'manual failover: demoting myself')
 
     @patch('patroni.ha.Ha.demote')
     def test_failover_immediately_on_zero_master_start_timeout(self, demote):
@@ -686,7 +796,7 @@ class TestHa(unittest.TestCase):
         self.ha.has_lock = true
         self.ha.update_lock = true
         self.ha.fetch_node_status = get_node_status()  # accessible, in_recovery
-        self.assertEquals(self.ha.run_cycle(), 'stopped PostgreSQL to fail over after a crash')
+        self.assertEqual(self.ha.run_cycle(), 'stopped PostgreSQL to fail over after a crash')
         demote.assert_called_once()
 
     @patch('patroni.postgresql.Postgresql.follow')
@@ -748,18 +858,22 @@ class TestHa(unittest.TestCase):
         self.p.pick_synchronous_standby = Mock(return_value=('other2', True))
         self.ha.run_cycle()
         self.ha.dcs.get_cluster.assert_called_once()
-        self.assertEquals(self.ha.dcs.write_sync_state.call_count, 2)
+        self.assertEqual(self.ha.dcs.write_sync_state.call_count, 2)
 
         # Test updating sync standby key failed due to race
         self.ha.dcs.write_sync_state = Mock(side_effect=[True, False])
         self.ha.run_cycle()
-        self.assertEquals(self.ha.dcs.write_sync_state.call_count, 2)
+        self.assertEqual(self.ha.dcs.write_sync_state.call_count, 2)
+
+        # Test updating sync standby key failed due to DCS being not accessible
+        self.ha.dcs.write_sync_state = Mock(return_value=True)
+        self.ha.dcs.get_cluster = Mock(side_effect=DCSError('foo'))
+        self.ha.run_cycle()
 
         # Test changing sync standby failed due to race
-        self.ha.dcs.write_sync_state = Mock(return_value=True)
         self.ha.dcs.get_cluster = Mock(return_value=get_cluster_initialized_with_leader(sync=('somebodyelse', None)))
         self.ha.run_cycle()
-        self.assertEquals(self.ha.dcs.write_sync_state.call_count, 1)
+        self.assertEqual(self.ha.dcs.write_sync_state.call_count, 2)
 
         # Test sync set to '*' when synchronous_mode_strict is enabled
         mock_set_sync.reset_mock()
@@ -780,7 +894,7 @@ class TestHa(unittest.TestCase):
         self.ha.cluster = get_cluster_initialized_with_leader(sync=('other', None))
 
         # When we just became master nobody is sync
-        self.assertEquals(self.ha.enforce_master_role('msg', 'promote msg'), 'promote msg')
+        self.assertEqual(self.ha.enforce_master_role('msg', 'promote msg'), 'promote msg')
         mock_set_sync.assert_called_once_with(None)
         mock_write_sync.assert_called_once_with('leader', None, index=0)
 
@@ -808,7 +922,7 @@ class TestHa(unittest.TestCase):
         self.ha.run_cycle()
         mock_acquire.assert_not_called()
         mock_follow.assert_called_once()
-        self.assertEquals(mock_follow.call_args[0][0], None)
+        self.assertEqual(mock_follow.call_args[0][0], None)
         mock_write_sync.assert_not_called()
 
         mock_follow.reset_mock()
@@ -859,15 +973,15 @@ class TestHa(unittest.TestCase):
 
     def test_effective_tags(self):
         self.ha._disable_sync = True
-        self.assertEquals(self.ha.get_effective_tags(), {'foo': 'bar', 'nosync': True})
+        self.assertEqual(self.ha.get_effective_tags(), {'foo': 'bar', 'nosync': True})
         self.ha._disable_sync = False
-        self.assertEquals(self.ha.get_effective_tags(), {'foo': 'bar'})
+        self.assertEqual(self.ha.get_effective_tags(), {'foo': 'bar'})
 
     def test_restore_cluster_config(self):
         self.ha.cluster.config.data.clear()
         self.ha.has_lock = true
         self.ha.cluster.is_unlocked = false
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
 
     def test_watch(self):
         self.ha.cluster = get_cluster_initialized_with_leader()
@@ -886,21 +1000,24 @@ class TestHa(unittest.TestCase):
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.ha.has_lock = true
         self.p.data_directory_empty = true
-        self.assertEquals(self.ha.run_cycle(), 'released leader key voluntarily as data dir empty and currently leader')
-        self.assertEquals(self.p.role, 'uninitialized')
+        self.assertEqual(self.ha.run_cycle(), 'released leader key voluntarily as data dir empty and currently leader')
+        self.assertEqual(self.p.role, 'uninitialized')
 
         # as has_lock is mocked out, we need to fake the leader key release
         self.ha.has_lock = false
         # will not say bootstrap from leader as replica can't self elect
-        self.assertEquals(self.ha.run_cycle(), "trying to bootstrap from replica 'other'")
+        self.assertEqual(self.ha.run_cycle(), "trying to bootstrap from replica 'other'")
 
+    @patch('psycopg2.connect', psycopg2_connect)
     def test_update_cluster_history(self):
-        self.p.get_master_timeline = Mock(return_value=1)
         self.ha.has_lock = true
         self.ha.cluster.is_unlocked = false
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        for tl in (1, 3):
+            self.p.get_master_timeline = Mock(return_value=tl)
+            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
@@ -911,6 +1028,15 @@ class TestHa(unittest.TestCase):
         self.ha.has_lock = true
         self.ha.cluster.is_unlocked = false
         self.ha.is_paused = true
-        self.assertEquals(self.ha.run_cycle(), 'PAUSE: no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'PAUSE: no action.  i am the leader with the lock')
         self.ha.is_paused = false
-        self.assertEquals(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+        self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+
+    @patch('psycopg2.connect', psycopg2_connect)
+    def test_permanent_logical_slots_after_promote(self):
+        config = ClusterConfig(1, {'slots': {'l': {'database': 'postgres', 'plugin': 'test_decoding'}}}, 1)
+        self.ha.cluster = get_cluster_initialized_without_leader(cluster_config=config)
+        self.assertEqual(self.ha.run_cycle(), 'acquired session lock as a leader')
+        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')

tests/test_kubernetes.py

@@ -1,3 +1,4 @@
+import time
 import unittest
 
 from mock import Mock, patch
@@ -33,13 +34,14 @@ class TestKubernetes(unittest.TestCase):
     @patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod)
     def setUp(self):
         self.k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'retry_timeout': 10, 'labels': {'f': 'b'}})
-        with patch('time.time', Mock(return_value=1)):
+        self.k.get_cluster()
+
+    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()
 
-    @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)
-    def test_get_cluster(self):
-        self.k.get_cluster()
         with patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', Mock(side_effect=Exception)):
             self.assertRaises(KubernetesError, self.k.get_cluster)
 
@@ -50,6 +52,13 @@ class TestKubernetes(unittest.TestCase):
                         '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'
@@ -65,7 +74,7 @@ class TestKubernetes(unittest.TestCase):
 
     @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', Mock(return_value=True))
     def test_touch_member(self):
-        self.k.touch_member({})
+        self.k.touch_member({'role': 'replica'})
         self.k._name = 'p-1'
         self.k.touch_member({'state': 'running', 'role': 'replica'})
         self.k.touch_member({'state': 'stopped', 'role': 'master'})
@@ -105,3 +114,15 @@ class TestKubernetes(unittest.TestCase):
 
     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))
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_service',
+                  Mock(side_effect=[True, False, k8s_client.rest.ApiException(500, '')]))
+    def test__create_config_service(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.patch_or_create_config({'foo': 'bar'}))
+        self.assertIsNotNone(k.patch_or_create_config({'foo': 'bar'}))
+        k.touch_member({'state': 'running', 'role': 'replica'})

tests/test_log.py

@@ -0,0 +1,36 @@
+import os
+import sys
+import unittest
+import yaml
+
+from mock import Mock, patch
+from patroni.config import Config
+from patroni.log import PatroniLogger
+
+
+class TestPatroniLogger(unittest.TestCase):
+
+    @patch('logging.FileHandler._open', Mock())
+    def test_patroni_logger(self):
+        config = {
+            'log': {
+                'dir': 'foo',
+                'file_size': 4096,
+                'file_num': 5,
+                'loggers': {
+                    'foo.bar': 'INFO'
+                }
+            },
+            'restapi': {}, 'postgresql': {'data_dir': 'foo'}
+        }
+        sys.argv = ['patroni.py']
+        os.environ[Config.PATRONI_CONFIG_VARIABLE] = yaml.dump(config, default_flow_style=False)
+        logger = PatroniLogger()
+        patroni_config = Config()
+        logger.reload_config(patroni_config['log'])
+
+        self.assertEqual(logger.handler.maxBytes, config['log']['file_size'])
+        self.assertEqual(logger.handler.backupCount, config['log']['file_num'])
+
+        config['log'].pop('dir')
+        logger.reload_config(config['log'])

tests/test_patroni.py

@@ -67,16 +67,12 @@ class TestPatroni(unittest.TestCase):
                     patroni_main()
 
     @patch('os.getpid')
-    @patch('subprocess.Popen', )
+    @patch('multiprocessing.Process')
     @patch('patroni.patroni_main', Mock())
-    def test_patroni_main(self, mock_popen, mock_getpid):
+    def test_patroni_main(self, mock_process, mock_getpid):
         mock_getpid.return_value = 2
         _main()
 
-        with patch('sys.frozen', Mock(return_value=True), create=True):
-            sys.argv = ['/patroni', 'pg_ctl_start', 'postgres', '-D', '/data', '--max_connections=100']
-            _main()
-
         mock_getpid.return_value = 1
 
         def mock_signal(signo, handler):
@@ -91,13 +87,13 @@ class TestPatroni(unittest.TestCase):
         ref = {'passtochild': lambda signo, stack_frame: 0}
 
         def mock_sighup(signo, handler):
-            if signo == signal.SIGHUP:
+            if hasattr(signal, 'SIGHUP') and signo == signal.SIGHUP:
                 ref['passtochild'] = handler
 
-        def mock_wait():
+        def mock_join():
             ref['passtochild'](0, None)
 
-        mock_popen.return_value.wait = mock_wait
+        mock_process.return_value.join = mock_join
         with patch('signal.signal', mock_sighup), patch('os.kill', Mock()):
             self.assertIsNone(_main())
 
@@ -122,6 +118,7 @@ class TestPatroni(unittest.TestCase):
         self.assertRaises(SystemExit, self.p.sigterm_handler)
 
     def test_schedule_next_run(self):
+        self.p.ha.cluster = Mock()
         self.p.ha.dcs.watch = Mock(return_value=True)
         self.p.schedule_next_run()
         self.p.next_run = time.time() - self.p.dcs.loop_wait - 1

tests/test_postgresql.py

@@ -8,13 +8,14 @@ import unittest
 
 from mock import Mock, MagicMock, PropertyMock, patch, mock_open
 from patroni.async_executor import CriticalTask
-from patroni.dcs import Cluster, Leader, Member, SyncState
+from patroni.dcs import Cluster, ClusterConfig, Leader, Member, RemoteMember, SyncState
 from patroni.exceptions import PostgresConnectionException, PostgresException
 from patroni.postgresql import Postgresql, STATE_REJECT, STATE_NO_RESPONSE
 from patroni.postmaster import PostmasterProcess
 from patroni.utils import RetryFailedError
 from six.moves import builtins
 from threading import Thread, current_thread
+from tempfile import gettempdir
 
 
 class MockCursor(object):
@@ -28,15 +29,15 @@ class MockCursor(object):
     def execute(self, sql, *params):
         if sql.startswith('blabla'):
             raise psycopg2.ProgrammingError()
-        elif sql == 'CHECKPOINT':
+        elif sql == 'CHECKPOINT' or sql.startswith('SELECT pg_catalog.pg_create_'):
             raise psycopg2.OperationalError()
         elif sql.startswith('RetryFailedError'):
             raise RetryFailedError('retry')
         elif sql.startswith('SELECT slot_name'):
-            self.results = [('blabla',), ('foobar',)]
-        elif sql.startswith('SELECT CASE WHEN pg_is_in_recovery()'):
+            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)]
-        elif sql.startswith('SELECT pg_is_in_recovery()'):
+        elif sql.startswith('SELECT pg_catalog.pg_is_in_recovery()'):
             self.results = [(False, 2)]
         elif sql.startswith('WITH replication_info AS ('):
             replication_info = '[{"application_name":"walreceiver","client_addr":"1.2.3.4",' +\
@@ -53,7 +54,7 @@ class MockCursor(object):
             self.results = [('1', 2, '0/402EEC0', '')]
         elif sql.startswith('SELECT isdir, modification'):
             self.results = [(False, datetime.datetime.now())]
-        elif sql.startswith('SELECT pg_read_file'):
+        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 '):
@@ -189,7 +190,8 @@ class TestPostgresql(unittest.TestCase):
         if not os.path.exists(self.data_dir):
             os.makedirs(self.data_dir)
         self.p = Postgresql({'name': 'test0', 'scope': 'batman', 'data_dir': self.data_dir,
-                             'config_dir': self.config_dir, 'retry_timeout': 10, 'pgpass': '/tmp/pgpass0',
+                             'config_dir': self.config_dir, 'retry_timeout': 10,
+                             'pgpass': os.path.join(gettempdir(), 'pgpass0'),
                              'listen': '127.0.0.2, 127.0.0.3:5432', 'connect_address': '127.0.0.2:5432',
                              'authentication': {'superuser': {'username': 'test', 'password': 'test'},
                                                 'replication': {'username': 'replicator', 'password': 'rep-pass'}},
@@ -308,7 +310,7 @@ class TestPostgresql(unittest.TestCase):
     def test_restart(self):
         self.p.start = Mock(return_value=False)
         self.assertFalse(self.p.restart())
-        self.assertEquals(self.p.state, 'restart failed (restarting)')
+        self.assertEqual(self.p.state, 'restart failed (restarting)')
 
     @patch.object(builtins, 'open', MagicMock())
     def test_write_pgpass(self):
@@ -317,10 +319,10 @@ class TestPostgresql(unittest.TestCase):
 
     def test_checkpoint(self):
         with patch.object(MockCursor, 'fetchone', Mock(return_value=(True, ))):
-            self.assertEquals(self.p.checkpoint({'user': 'postgres'}), 'is_in_recovery=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.assertEquals(self.p.checkpoint(), 'not accessible or not healty')
+        self.assertEqual(self.p.checkpoint(), 'not accessible or not healty')
 
     @patch.object(Postgresql, 'cancellable_subprocess_call')
     @patch('patroni.postgresql.Postgresql.write_pgpass', MagicMock(return_value=dict()))
@@ -345,10 +347,10 @@ class TestPostgresql(unittest.TestCase):
                           Mock(return_value={'Database cluster state': 'shut down in recovery',
                                              'Minimum recovery ending location': '0/0',
                                              "Min recovery ending loc's timeline": '0'})):
-            self.p.rewind_needed_and_possible(self.leader)
+            self.p.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])):
-                self.p.rewind_needed_and_possible(self.leader)
+                self.p.rewind_or_reinitialize_needed_and_possible(self.leader)
 
     @patch.object(Postgresql, 'start', Mock())
     @patch.object(Postgresql, 'can_rewind', PropertyMock(return_value=True))
@@ -357,21 +359,23 @@ class TestPostgresql(unittest.TestCase):
     def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery):
         mock_check_leader_is_not_in_recovery.return_value = False
         self.p.trigger_check_diverged_lsn()
-        self.assertFalse(self.p.rewind_needed_and_possible(self.leader))
+        self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
+        self.leader = self.leader.member
+        self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
         mock_check_leader_is_not_in_recovery.return_value = True
-        self.assertFalse(self.p.rewind_needed_and_possible(self.leader))
+        self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.p.trigger_check_diverged_lsn()
         with patch('psycopg2.connect', Mock(side_effect=Exception)):
-            self.assertFalse(self.p.rewind_needed_and_possible(self.leader))
+            self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.p.trigger_check_diverged_lsn()
         with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 2, '0/0'), ('', b'3\t0/40159C0\tn\n')])):
-            self.assertFalse(self.p.rewind_needed_and_possible(self.leader))
+            self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.p.trigger_check_diverged_lsn()
         with patch.object(MockCursor, 'fetchone', Mock(return_value=('', 1, '0/0'))):
             with patch.object(Postgresql, '_get_local_timeline_lsn', Mock(return_value=(1, '0/0'))):
-                self.assertFalse(self.p.rewind_needed_and_possible(self.leader))
+                self.assertFalse(self.p.rewind_or_reinitialize_needed_and_possible(self.leader))
             self.p.trigger_check_diverged_lsn()
-            self.assertTrue(self.p.rewind_needed_and_possible(self.leader))
+            self.assertTrue(self.p.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):
@@ -401,7 +405,9 @@ class TestPostgresql(unittest.TestCase):
     @patch.object(Postgresql, 'is_running', Mock(return_value=False))
     @patch.object(Postgresql, 'start', Mock())
     def test_follow(self):
-        self.p.follow(None)
+        self.p.call_nowait('on_start')
+        m = RemoteMember('1', {'restore_command': '2', 'recovery_min_apply_delay': 3, 'archive_cleanup_command': '4'})
+        self.p.follow(m)
 
     @patch('subprocess.check_output', Mock(return_value=0, side_effect=pg_controldata_string))
     def test_can_rewind(self):
@@ -420,16 +426,20 @@ class TestPostgresql(unittest.TestCase):
     def test_create_replica(self, mock_cancellable_subprocess_call):
         self.p.delete_trigger_file = Mock(side_effect=OSError)
 
+        self.p.config['create_replica_methods'] = ['pgBackRest']
+        self.p.config['pgBackRest'] = {'command': 'pgBackRest', 'keep_data': True, 'no_params': True}
+        mock_cancellable_subprocess_call.return_value = 0
+        self.assertEqual(self.p.create_replica(self.leader), 0)
+
         self.p.config['create_replica_methods'] = ['wale', 'basebackup']
         self.p.config['wale'] = {'command': 'foo'}
-        mock_cancellable_subprocess_call.return_value = 0
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
         del self.p.config['wale']
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.config['create_replica_methods'] = ['basebackup']
         self.p.config['basebackup'] = [{'max_rate': '100M'}, 'no-sync']
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.config['basebackup'] = [{'max_rate': '100M', 'compress': '9'}]
         with mock.patch('patroni.postgresql.logger.error', new_callable=Mock()) as mock_logger:
@@ -446,24 +456,24 @@ class TestPostgresql(unittest.TestCase):
                             "not matching {0}".format(mock_logger.call_args[0][0]))
 
         self.p.config['basebackup'] = {"foo": "bar"}
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.config['create_replica_methods'] = ['wale', 'basebackup']
         del self.p.config['basebackup']
         mock_cancellable_subprocess_call.return_value = 1
-        self.assertEquals(self.p.create_replica(self.leader), 1)
+        self.assertEqual(self.p.create_replica(self.leader), 1)
 
         mock_cancellable_subprocess_call.side_effect = Exception('foo')
-        self.assertEquals(self.p.create_replica(self.leader), 1)
+        self.assertEqual(self.p.create_replica(self.leader), 1)
 
         mock_cancellable_subprocess_call.side_effect = [1, 0]
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         mock_cancellable_subprocess_call.side_effect = [Exception(), 0]
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.cancel()
-        self.assertEquals(self.p.create_replica(self.leader), 1)
+        self.assertEqual(self.p.create_replica(self.leader), 1)
 
     @patch('time.sleep', Mock())
     @patch.object(Postgresql, 'cancellable_subprocess_call')
@@ -477,18 +487,18 @@ class TestPostgresql(unittest.TestCase):
         self.p.config['create_replica_method'] = ['wale', 'basebackup']
         self.p.config['wale'] = {'command': 'foo'}
         mock_cancellable_subprocess_call.return_value = 0
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
         del self.p.config['wale']
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.config['create_replica_method'] = ['basebackup']
         self.p.config['basebackup'] = [{'max_rate': '100M'}, 'no-sync']
-        self.assertEquals(self.p.create_replica(self.leader), 0)
+        self.assertEqual(self.p.create_replica(self.leader), 0)
 
         self.p.config['create_replica_method'] = ['wale', 'basebackup']
         del self.p.config['basebackup']
         mock_cancellable_subprocess_call.return_value = 1
-        self.assertEquals(self.p.create_replica(self.leader), 1)
+        self.assertEqual(self.p.create_replica(self.leader), 1)
 
     def test_basebackup(self):
         self.p.cancel()
@@ -497,23 +507,25 @@ class TestPostgresql(unittest.TestCase):
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
     def test_sync_replication_slots(self):
         self.p.start()
-        cluster = Cluster(True, None, self.leader, 0, [self.me, self.other, self.leadermem], None, None, None)
+        config = ClusterConfig(1, {'slots': {'ls': {'database': 'a', 'plugin': 'b'},
+                                             'A': 0, 'test_3': 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.sync_replication_slots(cluster)
         self.p.sync_replication_slots(cluster)
         with mock.patch('patroni.postgresql.Postgresql.role', new_callable=PropertyMock(return_value='replica')):
             self.p.sync_replication_slots(cluster)
-        with mock.patch('patroni.postgresql.logger.error', new_callable=Mock()) as errorlog_mock:
+        with patch.object(Postgresql, 'drop_replication_slot', Mock(return_value=True)),\
+                patch('patroni.dcs.logger.error', new_callable=Mock()) as errorlog_mock:
             self.p.query = Mock()
             alias1 = Member(0, 'test-3', 28, {'conn_url': 'postgres://replicator:[email protected]:5436/postgres'})
             alias2 = Member(0, 'test.3', 28, {'conn_url': 'postgres://replicator:[email protected]:5436/postgres'})
             cluster.members.extend([alias1, alias2])
             self.p.sync_replication_slots(cluster)
-            errorlog_mock.assert_called_once()
-            self.assertTrue("test-3" in errorlog_mock.call_args[0][1],
-                            "non matching {0}".format(errorlog_mock.call_args[0][1]))
-            self.assertTrue("test.3" in errorlog_mock.call_args[0][1],
-                            "non matching {0}".format(errorlog_mock.call_args[0][1]))
+            self.assertEqual(errorlog_mock.call_count, 5)
+            ca = errorlog_mock.call_args_list[0][0][1]
+            self.assertTrue("test-3" in ca, "non matching {0}".format(ca))
+            self.assertTrue("test.3" in ca, "non matching {0}".format(ca))
 
     @patch.object(MockCursor, 'execute', Mock(side_effect=psycopg2.OperationalError))
     def test__query(self):
@@ -549,25 +561,25 @@ class TestPostgresql(unittest.TestCase):
         self.assertTrue(self.p.promote(0))
 
     def test_timeline_wal_position(self):
-        self.assertEquals(self.p.timeline_wal_position(), (1, 2))
+        self.assertEqual(self.p.timeline_wal_position(), (1, 2))
         Thread(target=self.p.timeline_wal_position).start()
 
     @patch.object(PostmasterProcess, 'from_pidfile')
     def test_is_running(self, mock_frompidfile):
         # Cached postmaster running
         mock_postmaster = self.p._postmaster_proc = MockPostmaster()
-        self.assertEquals(self.p.is_running(), mock_postmaster)
+        self.assertEqual(self.p.is_running(), mock_postmaster)
 
         # Cached postmaster not running, no postmaster running
         mock_postmaster.is_running.return_value = False
         mock_frompidfile.return_value = None
-        self.assertEquals(self.p.is_running(), None)
-        self.assertEquals(self.p._postmaster_proc, None)
+        self.assertEqual(self.p.is_running(), None)
+        self.assertEqual(self.p._postmaster_proc, None)
 
         # No cached postmaster, postmaster running
         mock_frompidfile.return_value = mock_postmaster2 = MockPostmaster()
-        self.assertEquals(self.p.is_running(), mock_postmaster2)
-        self.assertEquals(self.p._postmaster_proc, mock_postmaster2)
+        self.assertEqual(self.p.is_running(), mock_postmaster2)
+        self.assertEqual(self.p._postmaster_proc, mock_postmaster2)
 
     @patch('shlex.split', Mock(side_effect=OSError))
     def test_call_nowait(self):
@@ -615,6 +627,7 @@ class TestPostgresql(unittest.TestCase):
             self.assertTrue('host replication replicator 127.0.0.1/32 md5\n' in lines)
 
     @patch.object(Postgresql, 'cancellable_subprocess_call')
+    @patch.object(Postgresql, 'get_major_version', Mock(return_value=90600))
     def test_custom_bootstrap(self, mock_cancellable_subprocess_call):
         self.p.config.pop('pg_hba')
         config = {'method': 'foo', 'foo': {'command': 'bar'}}
@@ -623,7 +636,7 @@ class TestPostgresql(unittest.TestCase):
         self.assertFalse(self.p.bootstrap(config))
 
         mock_cancellable_subprocess_call.return_value = 0
-        with patch('subprocess.Popen', Mock(side_effect=Exception("42"))),\
+        with patch('multiprocessing.Process', Mock(side_effect=Exception("42"))),\
                 patch('os.path.isfile', Mock(return_value=True)),\
                 patch('os.unlink', Mock()),\
                 patch.object(Postgresql, 'save_configuration_files', Mock()),\
@@ -644,9 +657,12 @@ class TestPostgresql(unittest.TestCase):
 
     @patch('time.sleep', Mock())
     @patch('os.unlink', Mock())
+    @patch('shutil.copy', Mock())
+    @patch('os.path.isfile', Mock(return_value=True))
     @patch.object(Postgresql, 'run_bootstrap_post_init', Mock(return_value=True))
     @patch.object(Postgresql, '_custom_bootstrap', Mock(return_value=True))
     @patch.object(Postgresql, 'start', Mock(return_value=True))
+    @patch.object(Postgresql, 'get_major_version', Mock(return_value=90600))
     def test_post_bootstrap(self):
         config = {'method': 'foo', 'foo': {'command': 'bar'}}
         self.p.bootstrap(config)
@@ -670,7 +686,7 @@ class TestPostgresql(unittest.TestCase):
         self.p.set_state('stopped')
         self.p.reload_config({'authentication': {'superuser': {'username': 'p', 'password': 'p'},
                                                  'replication': {'username': 'r', 'password': 'r'}},
-                              'listen': '*', 'retry_timeout': 10, 'parameters': {'hba_file': 'foo'}})
+                              'listen': '*', 'retry_timeout': 10, 'parameters': {'wal_level': '', 'hba_file': 'foo'}})
         with patch.object(Postgresql, 'restart', Mock()) as mock_restart:
             self.p.post_bootstrap({}, task)
             mock_restart.assert_called_once()
@@ -686,13 +702,13 @@ class TestPostgresql(unittest.TestCase):
         mock_cancellable_subprocess_call.assert_called()
         args, kwargs = mock_cancellable_subprocess_call.call_args
         self.assertTrue('PGPASSFILE' in kwargs['env'])
-        self.assertEquals(args[0], ['/bin/false', 'postgres://127.0.0.2:5432/postgres'])
+        self.assertEqual(args[0], ['/bin/false', 'postgres://127.0.0.2:5432/postgres'])
 
         mock_cancellable_subprocess_call.reset_mock()
         self.p._local_address.pop('host')
         self.assertTrue(self.p.run_bootstrap_post_init({'post_init': '/bin/false'}))
         mock_cancellable_subprocess_call.assert_called()
-        self.assertEquals(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', 'postgres://:5432/postgres'])
 
         mock_cancellable_subprocess_call.side_effect = OSError
         self.assertFalse(self.p.run_bootstrap_post_init({'post_init': '/bin/false'}))
@@ -704,13 +720,21 @@ class TestPostgresql(unittest.TestCase):
     @patch('os.listdir', Mock(return_value=['recovery.conf']))
     @patch('os.path.exists', Mock(return_value=True))
     def test_get_postgres_role_from_data_directory(self):
-        self.assertEquals(self.p.get_postgres_role_from_data_directory(), 'replica')
+        self.assertEqual(self.p.get_postgres_role_from_data_directory(), 'replica')
 
     def test_remove_data_directory(self):
+        def _symlink(src, dst):
+            try:
+                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.data_dir, 'foo'))
+        _symlink('foo', os.path.join(self.data_dir, 'pg_wal'))
         self.p.remove_data_directory()
         open(self.data_dir, 'w').close()
         self.p.remove_data_directory()
-        os.symlink('unexisting', self.data_dir)
+        _symlink('unexisting', self.data_dir)
         with patch('os.unlink', Mock(side_effect=OSError)):
             self.p.remove_data_directory()
         self.p.remove_data_directory()
@@ -719,13 +743,13 @@ class TestPostgresql(unittest.TestCase):
     def test_controldata(self):
         with patch('subprocess.check_output', Mock(return_value=0, side_effect=pg_controldata_string)):
             data = self.p.controldata()
-            self.assertEquals(len(data), 50)
-            self.assertEquals(data['Database cluster state'], 'shut down in recovery')
-            self.assertEquals(data['wal_log_hints setting'], 'on')
-            self.assertEquals(int(data['Database block size']), 8192)
+            self.assertEqual(len(data), 50)
+            self.assertEqual(data['Database cluster state'], 'shut down in recovery')
+            self.assertEqual(data['wal_log_hints setting'], 'on')
+            self.assertEqual(int(data['Database block size']), 8192)
 
         with patch('subprocess.check_output', Mock(side_effect=subprocess.CalledProcessError(1, ''))):
-            self.assertEquals(self.p.controldata(), {})
+            self.assertEqual(self.p.controldata(), {})
 
     @patch('patroni.postgresql.Postgresql._version_file_exists', Mock(return_value=True))
     @patch('subprocess.check_output', MagicMock(return_value=0, side_effect=pg_controldata_string))
@@ -779,9 +803,9 @@ class TestPostgresql(unittest.TestCase):
     @patch.object(Postgresql, '_version_file_exists', Mock(return_value=True))
     def test_get_major_version(self):
         with patch.object(builtins, 'open', mock_open(read_data='9.4')):
-            self.assertEquals(self.p.get_major_version(), 90400)
+            self.assertEqual(self.p.get_major_version(), 90400)
         with patch.object(builtins, 'open', Mock(side_effect=Exception)):
-            self.assertEquals(self.p.get_major_version(), 0)
+            self.assertEqual(self.p.get_major_version(), 0)
 
     def test_postmaster_start_time(self):
         with patch.object(MockCursor, "fetchone", Mock(return_value=('foo', True, '', '', '', '', False))):
@@ -793,31 +817,31 @@ class TestPostgresql(unittest.TestCase):
         with patch('subprocess.call', return_value=0):
             self.p._state = 'starting'
             self.assertFalse(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'running')
+            self.assertEqual(self.p.state, 'running')
 
         with patch('subprocess.call', return_value=1):
             self.p._state = 'starting'
             self.assertTrue(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'starting')
+            self.assertEqual(self.p.state, 'starting')
 
         with patch('subprocess.call', return_value=2):
             self.p._state = 'starting'
             self.assertFalse(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'start failed')
+            self.assertEqual(self.p.state, 'start failed')
 
         with patch('subprocess.call', return_value=0):
             self.p._state = 'running'
             self.assertFalse(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'running')
+            self.assertEqual(self.p.state, 'running')
 
         with patch('subprocess.call', return_value=127):
             self.p._state = 'running'
             self.assertFalse(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'running')
+            self.assertEqual(self.p.state, 'running')
 
             self.p._state = 'starting'
             self.assertFalse(self.p.check_for_startup())
-            self.assertEquals(self.p.state, 'running')
+            self.assertEqual(self.p.state, 'running')
 
     def test_wait_for_startup(self):
         state = {'sleeps': 0, 'num_rejects': 0, 'final_return': 0}
@@ -842,12 +866,12 @@ class TestPostgresql(unittest.TestCase):
 
                 self.p._state = 'stopped'
                 self.assertTrue(self.p.wait_for_startup())
-                self.assertEquals(state['sleeps'], 0)
+                self.assertEqual(state['sleeps'], 0)
 
                 self.p._state = 'starting'
                 state['num_rejects'] = 5
                 self.assertTrue(self.p.wait_for_startup())
-                self.assertEquals(state['sleeps'], 5)
+                self.assertEqual(state['sleeps'], 5)
 
                 self.p._state = 'starting'
                 state['sleeps'] = 0
@@ -858,7 +882,7 @@ class TestPostgresql(unittest.TestCase):
                 state['sleeps'] = 0
                 state['final_return'] = 0
                 self.assertFalse(self.p.wait_for_startup(timeout=2))
-                self.assertEquals(state['sleeps'], 3)
+                self.assertEqual(state['sleeps'], 3)
 
         with patch.object(Postgresql, 'check_startup_state_changed', Mock(return_value=False)):
             self.p.cancel()
@@ -874,30 +898,30 @@ class TestPostgresql(unittest.TestCase):
                     (self.me.name, 'streaming', 'async'),
                     (self.other.name, 'streaming', 'async'),
                 ]):
-            self.assertEquals(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, True))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, True))
 
         with patch.object(Postgresql, "query", return_value=[
                     (self.me.name, 'streaming', 'async'),
                     (self.leadermem.name, 'streaming', 'potential'),
                     (self.other.name, 'streaming', 'async'),
                 ]):
-            self.assertEquals(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.leadermem.name, False))
 
         with patch.object(Postgresql, "query", return_value=[
                     (self.me.name, 'streaming', 'async'),
                     (self.other.name, 'streaming', 'async'),
                 ]):
-            self.assertEquals(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
 
         with patch.object(Postgresql, "query", return_value=[
                     ('missing', 'streaming', 'sync'),
                     (self.me.name, 'streaming', 'async'),
                     (self.other.name, 'streaming', 'async'),
                 ]):
-            self.assertEquals(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), (self.me.name, False))
 
         with patch.object(Postgresql, "query", return_value=[]):
-            self.assertEquals(self.p.pick_synchronous_standby(cluster), (None, False))
+            self.assertEqual(self.p.pick_synchronous_standby(cluster), (None, False))
 
     def test_set_sync_standby(self):
         def value_in_conf():
@@ -908,22 +932,22 @@ class TestPostgresql(unittest.TestCase):
 
         mock_reload = self.p.reload = Mock()
         self.p.set_synchronous_standby('n1')
-        self.assertEquals(value_in_conf(), "synchronous_standby_names = 'n1'")
+        self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
         mock_reload.assert_called()
 
         mock_reload.reset_mock()
         self.p.set_synchronous_standby('n1')
         mock_reload.assert_not_called()
-        self.assertEquals(value_in_conf(), "synchronous_standby_names = 'n1'")
+        self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n1'")
 
         self.p.set_synchronous_standby('n2')
         mock_reload.assert_called()
-        self.assertEquals(value_in_conf(), "synchronous_standby_names = 'n2'")
+        self.assertEqual(value_in_conf(), "synchronous_standby_names = 'n2'")
 
         mock_reload.reset_mock()
         self.p.set_synchronous_standby(None)
         mock_reload.assert_called()
-        self.assertEquals(value_in_conf(), None)
+        self.assertEqual(value_in_conf(), None)
 
     def test_get_server_parameters(self):
         config = {'synchronous_mode': True, 'parameters': {'wal_level': 'hot_standby'}, 'listen': '0'}
@@ -957,8 +981,8 @@ class TestPostgresql(unittest.TestCase):
 "--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.assertEquals(data['wal_level'], 'hot_standby')
-            self.assertEquals(int(data['max_replication_slots']), 5)
+            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
@@ -968,7 +992,7 @@ class TestPostgresql(unittest.TestCase):
     @patch('subprocess.Popen')
     def test_single_user_mode(self, subprocess_popen_mock):
         subprocess_popen_mock.return_value.wait.return_value = 0
-        self.assertEquals(self.p.single_user_mode('CHECKPOINT', {'archive_mode': 'on'}), 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))
@@ -980,16 +1004,18 @@ class TestPostgresql(unittest.TestCase):
         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.assertEquals(self.p.replica_cached_timeline(1), 2)
+        self.assertEqual(self.p.replica_cached_timeline(1), 2)
 
     def test_get_master_timeline(self):
-        self.assertEquals(self.p.get_master_timeline(), 1)
+        self.assertEqual(self.p.get_master_timeline(), 1)
 
     def test_cancellable_subprocess_call(self):
         self.p.cancel()

tests/test_postmaster.py

@@ -6,6 +6,18 @@ from patroni.postmaster import PostmasterProcess
 from six.moves import builtins
 
 
+class MockProcess(object):
+    def __init__(self, target, args):
+        self.target = target
+        self.args = args
+
+    def start(self):
+        self.target(*self.args)
+
+    def join(self):
+        pass
+
+
 class TestPostmasterProcess(unittest.TestCase):
     @patch('psutil.Process.__init__', Mock())
     def test_init(self):
@@ -46,28 +58,28 @@ class TestPostmasterProcess(unittest.TestCase):
     @patch('psutil.Process.__init__')
     def test_from_pid(self, mock_init):
         mock_init.side_effect = psutil.NoSuchProcess(123)
-        self.assertEquals(PostmasterProcess.from_pid(123), None)
+        self.assertEqual(PostmasterProcess.from_pid(123), None)
         mock_init.side_effect = None
-        self.assertNotEquals(PostmasterProcess.from_pid(123), None)
+        self.assertNotEqual(PostmasterProcess.from_pid(123), None)
 
     @patch('psutil.Process.__init__', Mock())
     @patch('psutil.Process.send_signal')
     @patch('psutil.Process.pid', Mock(return_value=123))
     def test_signal_stop(self, mock_send_signal):
         proc = PostmasterProcess(-123)
-        self.assertEquals(proc.signal_stop('immediate'), False)
+        self.assertEqual(proc.signal_stop('immediate'), False)
 
         mock_send_signal.side_effect = [None, psutil.NoSuchProcess(123), psutil.AccessDenied()]
         proc = PostmasterProcess(123)
-        self.assertEquals(proc.signal_stop('immediate'), None)
-        self.assertEquals(proc.signal_stop('immediate'), True)
-        self.assertEquals(proc.signal_stop('immediate'), False)
+        self.assertEqual(proc.signal_stop('immediate'), None)
+        self.assertEqual(proc.signal_stop('immediate'), True)
+        self.assertEqual(proc.signal_stop('immediate'), False)
 
     @patch('psutil.Process.__init__', Mock())
     @patch('psutil.wait_procs')
     def test_wait_for_user_backends_to_close(self, mock_wait):
         c1 = Mock()
-        c1.cmdline = Mock(return_value=["postgres: startup process"])
+        c1.cmdline = Mock(return_value=["postgres: startup process   "])
         c2 = Mock()
         c2.cmdline = Mock(return_value=["postgres: postgres postgres [local] idle"])
         c3 = Mock()
@@ -77,23 +89,27 @@ class TestPostmasterProcess(unittest.TestCase):
             self.assertIsNone(proc.wait_for_user_backends_to_close())
             mock_wait.assert_called_with([c2])
 
-        c3.cmdline = Mock(side_effect=psutil.AccessDenied(123))
-        with patch('psutil.Process.children', Mock(return_value=[c3])):
+        with patch('psutil.Process.children', Mock(side_effect=psutil.NoSuchProcess(123))):
             proc = PostmasterProcess(123)
             self.assertIsNone(proc.wait_for_user_backends_to_close())
 
     @patch('subprocess.Popen')
+    @patch('os.setsid', Mock(), create=True)
+    @patch('multiprocessing.Process', MockProcess)
     @patch.object(PostmasterProcess, 'from_pid')
     @patch.object(PostmasterProcess, '_from_pidfile')
     def test_start(self, mock_frompidfile, mock_frompid, mock_popen):
         mock_frompidfile.return_value._is_postmaster_process.return_value = False
         mock_frompid.return_value = "proc 123"
-        mock_popen.return_value.stdout.readline.return_value = '123'
-        self.assertEquals(PostmasterProcess.start('true', '/tmp', '/tmp/test.conf', []), "proc 123")
+        mock_popen.return_value.pid = 123
+        self.assertEqual(PostmasterProcess.start('true', '/tmp', '/tmp/test.conf', []), "proc 123")
         mock_frompid.assert_called_with(123)
 
         mock_frompidfile.side_effect = psutil.NoSuchProcess(123)
-        self.assertEquals(PostmasterProcess.start('true', '/tmp', '/tmp/test.conf', []), "proc 123")
+        self.assertEqual(PostmasterProcess.start('true', '/tmp', '/tmp/test.conf', []), "proc 123")
+
+        mock_popen.side_effect = Exception
+        self.assertIsNone(PostmasterProcess.start('true', '/tmp', '/tmp/test.conf', []))
 
     @patch('psutil.Process.__init__', Mock(side_effect=psutil.NoSuchProcess(123)))
     def test_read_postmaster_pidfile(self):

tests/test_utils.py

@@ -8,7 +8,7 @@ from patroni.utils import Retry, RetryFailedError, polling_loop
 class TestUtils(unittest.TestCase):
 
     def test_polling_loop(self):
-        self.assertEquals(list(polling_loop(0.001, interval=0.001)), [0])
+        self.assertEqual(list(polling_loop(0.001, interval=0.001)), [0])
 
 
 @patch('time.sleep', Mock())
@@ -29,21 +29,21 @@ class TestRetrySleeper(unittest.TestCase):
     def test_reset(self):
         retry = Retry(delay=0, max_tries=2)
         retry(self._fail())
-        self.assertEquals(retry._attempts, 1)
+        self.assertEqual(retry._attempts, 1)
         retry.reset()
-        self.assertEquals(retry._attempts, 0)
+        self.assertEqual(retry._attempts, 0)
 
     def test_too_many_tries(self):
         retry = Retry(delay=0)
         self.assertRaises(RetryFailedError, retry, self._fail(times=999))
-        self.assertEquals(retry._attempts, 1)
+        self.assertEqual(retry._attempts, 1)
 
     def test_maximum_delay(self):
         retry = Retry(delay=10, max_tries=100)
         retry(self._fail(times=10))
         self.assertTrue(retry._cur_delay < 4000, retry._cur_delay)
         # gevent's sleep function is picky about the type
-        self.assertEquals(type(retry._cur_delay), float)
+        self.assertEqual(type(retry._cur_delay), float)
 
     def test_deadline(self):
         retry = Retry(deadline=0.0001)

tests/test_watchdog.py

@@ -2,6 +2,7 @@ import ctypes
 import patroni.watchdog.linux as linuxwd
 import sys
 import unittest
+import os
 
 from mock import patch, Mock, PropertyMock
 from patroni.watchdog import Watchdog, WatchdogError
@@ -61,6 +62,7 @@ def mock_close(fd):
     mock_devices[fd].open = False
 
 
+@unittest.skipIf(os.name == 'nt', "Windows not supported")
 @patch('os.open', mock_open)
 @patch('os.write', mock_write)
 @patch('os.close', mock_close)
@@ -73,14 +75,14 @@ class TestWatchdog(unittest.TestCase):
     @patch.object(LinuxWatchdogDevice, 'can_be_disabled', PropertyMock(return_value=True))
     def test_unsafe_timeout_disable_watchdog_and_exit(self):
         watchdog = Watchdog({'ttl': 30, 'loop_wait': 15, 'watchdog': {'mode': 'required', 'safety_margin': -1}})
-        self.assertEquals(watchdog.activate(), False)
-        self.assertEquals(watchdog.is_running, False)
+        self.assertEqual(watchdog.activate(), False)
+        self.assertEqual(watchdog.is_running, False)
 
     @patch('platform.system', Mock(return_value='Linux'))
     @patch.object(LinuxWatchdogDevice, 'get_timeout', Mock(return_value=16))
     def test_timeout_does_not_ensure_safe_termination(self):
         Watchdog({'ttl': 30, 'loop_wait': 15, 'watchdog': {'mode': 'auto', 'safety_margin': -1}}).activate()
-        self.assertEquals(len(mock_devices), 2)
+        self.assertEqual(len(mock_devices), 2)
 
     @patch('platform.system', Mock(return_value='Linux'))
     @patch.object(Watchdog, 'is_running', PropertyMock(return_value=False))
@@ -99,29 +101,29 @@ class TestWatchdog(unittest.TestCase):
         watchdog = Watchdog({'ttl': 30, 'loop_wait': 10, 'watchdog': {'mode': 'required'}})
         watchdog.activate()
 
-        self.assertEquals(len(mock_devices), 2)
+        self.assertEqual(len(mock_devices), 2)
         device = mock_devices[-1]
         self.assertTrue(device.open)
 
-        self.assertEquals(device.timeout, 24)
+        self.assertEqual(device.timeout, 24)
 
         watchdog.keepalive()
-        self.assertEquals(len(device.writes), 1)
+        self.assertEqual(len(device.writes), 1)
 
         watchdog.disable()
         self.assertFalse(device.open)
-        self.assertEquals(device.writes[-1], b'V')
+        self.assertEqual(device.writes[-1], b'V')
 
     def test_invalid_timings(self):
         watchdog = Watchdog({'ttl': 30, 'loop_wait': 20, 'watchdog': {'mode': 'automatic', 'safety_margin': -1}})
         watchdog.activate()
-        self.assertEquals(len(mock_devices), 1)
+        self.assertEqual(len(mock_devices), 1)
         self.assertFalse(watchdog.is_running)
 
     def test_parse_mode(self):
         with patch('patroni.watchdog.base.logger.warning', new_callable=Mock()) as warning_mock:
             watchdog = Watchdog({'ttl': 30, 'loop_wait': 10, 'watchdog': {'mode': 'bad'}})
-            self.assertEquals(watchdog.config.mode, 'off')
+            self.assertEqual(watchdog.config.mode, 'off')
             warning_mock.assert_called_once()
 
     @patch('platform.system', Mock(return_value='Unknown'))
@@ -170,10 +172,11 @@ class TestNullWatchdog(unittest.TestCase):
         watchdog = NullWatchdog()
         self.assertTrue(watchdog.can_be_disabled)
         self.assertRaises(WatchdogError, watchdog.set_timeout, 1)
-        self.assertEquals(watchdog.describe(), 'NullWatchdog')
+        self.assertEqual(watchdog.describe(), 'NullWatchdog')
         self.assertIsInstance(NullWatchdog.from_config({}), NullWatchdog)
 
 
+@unittest.skipIf(os.name == 'nt', "Windows not supported")
 class TestLinuxWatchdogDevice(unittest.TestCase):
 
     def setUp(self):
@@ -210,7 +213,7 @@ class TestLinuxWatchdogDevice(unittest.TestCase):
         self.assertRaises(WatchdogError, self.impl.get_timeout)
         self.assertRaises(WatchdogError, self.impl.set_timeout, 10)
         # We still try to output a reasonable string even if getting info errors
-        self.assertEquals(self.impl.describe(), "Linux watchdog device")
+        self.assertEqual(self.impl.describe(), "Linux watchdog device")
 
     @patch('os.open', Mock(side_effect=OSError))
     def test_open(self):

tests/test_zookeeper.py

@@ -1,3 +1,4 @@
+import select
 import six
 import unittest
 
@@ -16,6 +17,7 @@ class MockKazooClient(Mock):
 
     def __init__(self, *args, **kwargs):
         super(MockKazooClient, self).__init__()
+        self._session_timeout = 30
 
     @property
     def client_id(self):
@@ -23,7 +25,7 @@ class MockKazooClient(Mock):
 
     @staticmethod
     def retry(func, *args, **kwargs):
-        func(*args, **kwargs)
+        return func(*args, **kwargs)
 
     def get(self, path, watch=None):
         if not isinstance(path, six.string_types):
@@ -113,6 +115,11 @@ class TestPatroniSequentialThreadingHandler(unittest.TestCase):
     def test_create_connection(self):
         self.assertIsNotNone(self.handler.create_connection(()))
         self.assertIsNotNone(self.handler.create_connection((), 40))
+        self.assertIsNotNone(self.handler.create_connection(timeout=40))
+
+    @patch.object(SequentialThreadingHandler, 'select', Mock(side_effect=ValueError))
+    def test_select(self):
+        self.assertRaises(select.error, self.handler.select)
 
 
 class TestZooKeeper(unittest.TestCase):
@@ -156,7 +163,7 @@ class TestZooKeeper(unittest.TestCase):
         self.zk.set_failover_value('Exception')
 
     def test_set_config_value(self):
-        self.zk.set_config_value('')
+        self.zk.set_config_value('', 1)
         self.zk.set_config_value('ok')
         self.zk.set_config_value('Exception')
 
@@ -179,7 +186,8 @@ class TestZooKeeper(unittest.TestCase):
         self.zk.touch_member({'retry': 'retry'})
         self.zk._fetch_cluster = True
         self.zk.get_cluster()
-        self.zk.touch_member({'retry': 'retry'})
+        self.zk.touch_member({'conn_url': 'postgres://repuser:rep-pass@localhost:5434/postgres',
+                              'api_url': 'http://127.0.0.1:8009/patroni'})
 
     def test_take_leader(self):
         self.zk.take_leader()