Merge branch 'master' of github.com:zalando/patroni into feature/terminaltables

README.rst

@@ -124,7 +124,7 @@ Running and Configuring
 To get started, do the following from different terminals:
 ::
 
-    > etcd --data-dir=data/etcd
+    > etcd --data-dir=data/etcd --enable-v2=true
     > ./patroni.py postgres0.yml
     > ./patroni.py postgres1.yml
 

docs/ENVIRONMENT.rst

@@ -126,7 +126,7 @@ REST API
 -  **PATRONI\_RESTAPI\_CERTFILE**: Specifies the file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
 -  **PATRONI\_RESTAPI\_KEYFILE**: Specifies the file with the secret key in the PEM format.
 -  **PATRONI\_RESTAPI\_CAFILE**: Specifies the file with the CA_BUNDLE with certificates of trusted CAs to use while verifying client certs.
--  **PATRONI\_RESTAPI\_VERIFY\_CLIENT**: ``none``, ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. If ``verify_client`` is set to ``optional`` or ``required`` basic-auth is not checked.
+-  **PATRONI\_RESTAPI\_VERIFY\_CLIENT**: ``none`` (default), ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. When ``required`` is used, then client authentication succeeds, if the certificate signature verification succeeds. For ``optional`` the client cert will only be checked for ``PUT``, ``POST``, ``PATCH``, and ``DELETE`` requests. 
 
 CTL
 ---

docs/SETTINGS.rst

@@ -15,6 +15,7 @@ Dynamic configuration is stored in the DCS (Distributed Configuration Store) and
 -  **ttl**: the TTL to acquire the leader lock (in seconds). Think of it as the length of time before initiation of the automatic failover process. Default value: 30
 -  **retry\_timeout**: timeout for DCS and PostgreSQL operation retries (in seconds). DCS or network issues shorter than this will not cause Patroni to demote the leader. Default value: 10
 -  **maximum\_lag\_on\_failover**: the maximum bytes a follower may lag to be able to participate in leader election.
+-  **max\_timelines\_history**: maximum number of timeline history items kept in DCS.  Default value: 0. When set to 0, it keeps the full history in DCS.
 -  **master\_start\_timeout**: the amount of time a master is allowed to recover from failures before failover is triggered (in seconds). Default is 300 seconds. When set to 0 failover is done immediately after a crash is detected if possible. When using asynchronous replication a failover can cause lost transactions. Worst case failover time for master failure is: loop\_wait + master\_start\_timeout + loop\_wait, unless master\_start\_timeout is zero, in which case it's just loop\_wait. Set the value according to your durability/availability tradeoff.
 - **master\_stop\_timeout**: The number of seconds Patroni is allowed to wait when stopping Postgres and effective only when synchronous_mode is enabled. When set to > 0 and the synchronous_mode is enabled, Patroni sends SIGKILL to the postmaster if the stop operation is running for more than the value set by master_stop_timeout. Set the value according to your durability/availability tradeoff. If the parameter is not set or set <= 0, master_stop_timeout does not apply.
 -  **synchronous\_mode**: turns on synchronous replication mode. In this mode a replica will be chosen as synchronous and only the latest leader and synchronous replica are able to participate in leader election. Synchronous mode makes sure that successfully committed transactions will not be lost at failover, at the cost of losing availability for writes when Patroni cannot ensure transaction durability. See :ref:`replication modes documentation <replication_modes>` for details.
@@ -62,25 +63,26 @@ Log
 
 Bootstrap configuration
 -----------------------
--  **dcs**: This section will be written into `/<namespace>/<scope>/config` of the given configuration store after initializing of new cluster. The global dynamic configuration for the cluster. Under the ``bootstrap.dcs`` you can put any of the parameters described in the :ref:`Dynamic Configuration settings <dynamic_configuration_settings>` and after Patroni initialized (bootstrapped) the new cluster, it will write this section into `/<namespace>/<scope>/config` of the configuration store. All later changes of ``bootstrap.dcs`` will not take any effect! If you want to change them please use either ``patronictl edit-config`` or Patroni :ref:`REST API <rest_api>`.
+-  **bootstrap**:
--  **method**: custom script to use for bootstrapping this cluster.
+    -  **dcs**: This section will be written into `/<namespace>/<scope>/config` of the given configuration store after initializing of new cluster. The global dynamic configuration for the cluster. Under the ``bootstrap.dcs`` you can put any of the parameters described in the :ref:`Dynamic Configuration settings <dynamic_configuration_settings>` and after Patroni initialized (bootstrapped) the new cluster, it will write this section into `/<namespace>/<scope>/config` of the configuration store. All later changes of ``bootstrap.dcs`` will not take any effect! If you want to change them please use either ``patronictl edit-config`` or Patroni :ref:`REST API <rest_api>`.
-   See :ref:`custom bootstrap methods documentation <custom_bootstrap>` for details.
+    -  **method**: custom script to use for bootstrapping this cluster.
-   When ``initdb`` is specified revert to the default ``initdb`` command. ``initdb`` is also triggered when no ``method``
+       See :ref:`custom bootstrap methods documentation <custom_bootstrap>` for details.
-   parameter is present in the configuration file.
+       When ``initdb`` is specified revert to the default ``initdb`` command. ``initdb`` is also triggered when no ``method``
--  **initdb**: List options to be passed on to initdb.
+       parameter is present in the configuration file.
-        -  **- data-checksums**: Must be enabled when pg_rewind is needed on 9.3.
+    -  **initdb**: List options to be passed on to initdb.
-        -  **- encoding: UTF8**: default encoding for new databases.
+            -  **- data-checksums**: Must be enabled when pg_rewind is needed on 9.3.
-        -  **- locale: UTF8**: default locale for new databases.
+            -  **- encoding: UTF8**: default encoding for new databases.
--  **pg\_hba**: list of lines that you should add to pg\_hba.conf.
+            -  **- locale: UTF8**: default locale for new databases.
-        -  **- host all all 0.0.0.0/0 md5**.
+    -  **pg\_hba**: list of lines that you should add to pg\_hba.conf.
-        -  **- host replication replicator 127.0.0.1/32 md5**: A line like this is required for replication.
+            -  **- host all all 0.0.0.0/0 md5**.
--  **users**: Some additional users which need to be created after initializing new cluster
+            -  **- host replication replicator 127.0.0.1/32 md5**: A line like this is required for replication.
-    -  **admin**: the name of user
+    -  **users**: Some additional users which need to be created after initializing new cluster
-        -  **password: zalando**:
+        -  **admin**: the name of user
-        -  **options**: list of options for CREATE USER statement
+            -  **password: zalando**:
-            -  **- createrole**
+            -  **options**: list of options for CREATE USER statement
-            -  **- createdb**
+                -  **- createrole**
--  **post\_bootstrap** or **post\_init**: An additional script that will be executed after initializing the cluster. The script receives a connection string URL (with the cluster superuser as a user name). The PGPASSFILE variable is set to the location of pgpass file.
+                -  **- createdb**
+    -  **post\_bootstrap** or **post\_init**: An additional script that will be executed after initializing the cluster. The script receives a connection string URL (with the cluster superuser as a user name). The PGPASSFILE variable is set to the location of pgpass file.
 
 .. _consul_settings:
 
@@ -146,83 +148,83 @@ Kubernetes
 
 PostgreSQL
 ----------
--  **authentication**:
+-  **postgresql**:
-    -  **superuser**:
+    -  **authentication**:
-        -  **username**: name for the superuser, set during initialization (initdb) and later used by Patroni to connect to the postgres.
+        -  **superuser**:
-        -  **password**: password for the superuser, set during initialization (initdb).
+            -  **username**: name for the superuser, set during initialization (initdb) and later used by Patroni to connect to the postgres.
-        -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **password**: password for the superuser, set during initialization (initdb).
-        -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
-        -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
-        -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
-        -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
-    -  **replication**:
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
-        -  **username**: replication username; the user will be created during initialization. Replicas will use this user to access master via streaming replication
+        -  **replication**:
-        -  **password**: replication password; the user will be created during initialization.
+            -  **username**: replication username; the user will be created during initialization. Replicas will use this user to access master via streaming replication
-        -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **password**: replication password; the user will be created during initialization.
-        -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
-        -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
-        -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
-        -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
-    -  **rewind**:
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
-        -  **username**: name for the user for ``pg_rewind``; the user will be created during initialization of postgres 11+ and all necessary `permissions <https://www.postgresql.org/docs/11/app-pgrewind.html#id-1.9.5.8.8>`__ will be granted.
+        -  **rewind**:
-        -  **password**: password for the user for ``pg_rewind``; the user will be created during initialization.
+            -  **username**: name for the user for ``pg_rewind``; the user will be created during initialization of postgres 11+ and all necessary `permissions <https://www.postgresql.org/docs/11/app-pgrewind.html#id-1.9.5.8.8>`__ will be granted.
-        -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
+            -  **password**: password for the user for ``pg_rewind``; the user will be created during initialization.
-        -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
+            -  **sslmode**: (optional) maps to the `sslmode <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLMODE>`__ connection parameter, which allows a client to specify the type of TLS negotiation mode with the server. For more information on how each mode works, please visit the `PostgreSQL documentation <https://www.postgresql.org/docs/current/libpq-ssl.html#LIBPQ-SSL-SSLMODE-STATEMENTS>`__. The default mode is ``prefer``.
-        -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
+            -  **sslkey**: (optional) maps to the `sslkey <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLKEY>`__ connection parameter, which specifies the location of the secret key used with the client's certificate.
-        -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
+            -  **sslcert**: (optional) maps to the `sslcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCERT>`__ connection parameter, which specifies the location of the client certificate.
-        -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
+            -  **sslrootcert**: (optional) maps to the `sslrootcert <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLROOTCERT>`__ connection parameter, which specifies the location of a file containing one ore more certificate authorities (CA) certificates that the client will use to verify a server's certificate.
--  **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.)
+            -  **sslcrl**: (optional) maps to the `sslcrl <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-SSLCRL>`__ connection parameter, which specifies the location of a file containing a certificate revocation list. A client will reject connecting to any server that has a certificate present in this list.
-        -  **on\_reload**: run this script when configuration reload is triggered.
+    -  **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\_restart**: run this script when the postgres restarts (without changing role).
+            -  **on\_reload**: run this script when configuration reload is triggered.
-        -  **on\_role\_change**: run this script when the postgres is being promoted or demoted.
+            -  **on\_restart**: run this script when the postgres restarts (without changing role).
-        -  **on\_start**: run this script when the postgres starts.
+            -  **on\_role\_change**: run this script when the postgres is being promoted or demoted.
-        -  **on\_stop**: run this script when the postgres stops.
+            -  **on\_start**: run this script when the postgres starts.
--  **connect\_address**: IP address + port through which Postgres is accessible from other nodes and applications.
+            -  **on\_stop**: run this script when the postgres stops.
--  **create\_replica\_methods**: an ordered list of the create methods for turning a Patroni node into a new replica.
+    -  **connect\_address**: IP address + port through which Postgres is accessible from other nodes and applications.
-   "basebackup" is the default method; other methods are assumed to refer to scripts, each of which is configured as its
+    -  **create\_replica\_methods**: an ordered list of the create methods for turning a Patroni node into a new replica.
-   own config item. See :ref:`custom replica creation methods documentation <custom_replica_creation>` for further explanation.
+       "basebackup" is the default method; other methods are assumed to refer to scripts, each of which is configured as its
--  **data\_dir**: The location of the Postgres data directory, either :ref:`existing <existing_data>` or to be initialized by Patroni.
+       own config item. See :ref:`custom replica creation methods documentation <custom_replica_creation>` for further explanation.
--  **config\_dir**: The location of the Postgres configuration directory, defaults to the data directory. Must be writable by Patroni.
+    -  **data\_dir**: The location of the Postgres data directory, either :ref:`existing <existing_data>` or to be initialized 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.
+    -  **config\_dir**: The location of the Postgres configuration directory, defaults to the data directory. Must be writable by Patroni.
--  **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.
+    -  **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.
--  **use\_unix\_socket**: specifies that Patroni should prefer to use unix sockets to connect to the cluster. Default value is ``false``. If ``unix_socket_directories`` is defined, Patroni will use the first suitable value from it to connect to the cluster and fallback to tcp if nothing is suitable. If ``unix_socket_directories`` is not specified in ``postgresql.parameters``, Patroni will assume that the default value should be used and omit ``host`` from the connection parameters.
+    -  **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.
--  **pgpass**: path to the `.pgpass <https://www.postgresql.org/docs/current/static/libpq-pgpass.html>`__ password file. Patroni creates this file before executing pg\_basebackup, the post_init script and under some other circumstances. The location must be writable by Patroni.
+    -  **use\_unix\_socket**: specifies that Patroni should prefer to use unix sockets to connect to the cluster. Default value is ``false``. If ``unix_socket_directories`` is defined, Patroni will use the first suitable value from it to connect to the cluster and fallback to tcp if nothing is suitable. If ``unix_socket_directories`` is not specified in ``postgresql.parameters``, Patroni will assume that the default value should be used and omit ``host`` from the connection parameters.
--  **recovery\_conf**: additional configuration settings written to recovery.conf when configuring follower.
+    -  **pgpass**: path to the `.pgpass <https://www.postgresql.org/docs/current/static/libpq-pgpass.html>`__ password file. Patroni creates this file before executing pg\_basebackup, the post_init script and under some other circumstances. The location must be writable by Patroni.
--  **custom\_conf** : path to an optional custom ``postgresql.conf`` file, that will be used in place of ``postgresql.base.conf``. The file must exist on all cluster nodes, be readable by PostgreSQL and will be included from its location on the real ``postgresql.conf``. Note that Patroni will not monitor this file for changes, nor backup it. However, its settings can still be overridden by Patroni's own configuration facilities - see :ref:`dynamic configuration <dynamic_configuration>` for details.
+    -  **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.
+    -  **custom\_conf** : path to an optional custom ``postgresql.conf`` file, that will be used in place of ``postgresql.base.conf``. The file must exist on all cluster nodes, be readable by PostgreSQL and will be included from its location on the real ``postgresql.conf``. Note that Patroni will not monitor this file for changes, nor backup it. However, its settings can still be overridden by Patroni's own configuration facilities - see :ref:`dynamic configuration <dynamic_configuration>` for details.
--  **pg\_hba**: list of lines that Patroni will use to generate ``pg_hba.conf``. This parameter has higher priority than ``bootstrap.pg_hba``. Together with :ref:`dynamic configuration <dynamic_configuration>` it simplifies management of ``pg_hba.conf``.
+    -  **parameters**: list of configuration settings for Postgres. Many of these are required for replication to work.
-        -  **- host all all 0.0.0.0/0 md5**.
+    -  **pg\_hba**: list of lines that Patroni will use to generate ``pg_hba.conf``. This parameter has higher priority than ``bootstrap.pg_hba``. Together with :ref:`dynamic configuration <dynamic_configuration>` it simplifies management of ``pg_hba.conf``.
-        -  **- host replication replicator 127.0.0.1/32 md5**: A line like this is required for replication.
+            -  **- host all all 0.0.0.0/0 md5**.
--  **pg\_ident**: list of lines that Patroni will use to generate ``pg_ident.conf``. Together with :ref:`dynamic configuration <dynamic_configuration>` it simplifies management of ``pg_ident.conf``.
+            -  **- host replication replicator 127.0.0.1/32 md5**: A line like this is required for replication.
-        -  **- mapname1 systemname1 pguser1**.
+    -  **pg\_ident**: list of lines that Patroni will use to generate ``pg_ident.conf``. Together with :ref:`dynamic configuration <dynamic_configuration>` it simplifies management of ``pg_ident.conf``.
-        -  **- mapname1 systemname2 pguser2**.
+            -  **- mapname1 systemname1 pguser1**.
--  **pg\_ctl\_timeout**: How long should pg_ctl wait when doing ``start``, ``stop`` or ``restart``. Default value is 60 seconds.
+            -  **- mapname1 systemname2 pguser2**.
--  **use\_pg\_rewind**: try to use pg\_rewind on the former leader when it joins cluster as a replica.
+    -  **pg\_ctl\_timeout**: How long should pg_ctl wait when doing ``start``, ``stop`` or ``restart``. Default value is 60 seconds.
--  **remove\_data\_directory\_on\_rewind\_failure**: If this option is enabled, Patroni will remove the PostgreSQL data directory and recreate the replica. Otherwise it will try to follow the new leader. Default value is **false**.
+    -  **use\_pg\_rewind**: try to use pg\_rewind on the former leader when it joins cluster as a replica.
--  **remove\_data\_directory\_on\_diverged\_timelines**: Patroni will remove the PostgreSQL data directory and recreate the replica if it notices that timelines are diverging and the former master can not start streaming from the new master. This option is useful when ``pg_rewind`` can not be used. Default value is **false**.
+    -  **remove\_data\_directory\_on\_rewind\_failure**: If this option is enabled, Patroni will remove the PostgreSQL data directory and recreate the replica. Otherwise it will try to follow the new leader. Default value is **false**.
--  **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".
+    -  **remove\_data\_directory\_on\_diverged\_timelines**: Patroni will remove the PostgreSQL data directory and recreate the replica if it notices that timelines are diverging and the former master can not start streaming from the new master. This option is useful when ``pg_rewind`` can not be used. Default value is **false**.
+    -  **replica\_method**: for each create_replica_methods other than basebackup, you would add a configuration section of the same name. At a minimum, this should include "command" with a full path to the actual script to be executed. Other configuration parameters will be passed along to the script in the form "parameter=value".
 
 REST API
 --------
--  **connect\_address**: IP address (or hostname) and port, to access the Patroni's :ref:`REST API <rest_api>`. All the members of the cluster must be able to connect to this address, so unless the Patroni setup is intended for a demo inside the localhost, this address must be a non "localhost" or loopback address (ie: "localhost" or "127.0.0.1"). It can serve as an endpoint for HTTP health checks (read below about the "listen" REST API parameter), and also for user queries (either directly or via the REST API), as well as for the health checks done by the cluster members during leader elections (for example, to determine whether the master is still running, or if there is a node which has a WAL position that is ahead of the one doing the query; etc.) The connect_address is put in the member key in DCS, making it possible to translate the member name into the address to connect to its REST API.
+-  **restapi**:
+        -  **connect\_address**: IP address (or hostname) and port, to access the Patroni's :ref:`REST API <rest_api>`. All the members of the cluster must be able to connect to this address, so unless the Patroni setup is intended for a demo inside the localhost, this address must be a non "localhost" or loopback address (ie: "localhost" or "127.0.0.1"). It can serve as an endpoint for HTTP health checks (read below about the "listen" REST API parameter), and also for user queries (either directly or via the REST API), as well as for the health checks done by the cluster members during leader elections (for example, to determine whether the master is still running, or if there is a node which has a WAL position that is ahead of the one doing the query; etc.) The connect_address is put in the member key in DCS, making it possible to translate the member name into the address to connect to its REST API.
         
--  **listen**: IP address (or hostname) and port that Patroni will listen to for the REST API - to provide also the same health checks and cluster messaging between the participating nodes, as described above. to provide health-check information for HAProxy (or any other load balancer capable of doing a HTTP "OPTION" or "GET" checks).
+        -  **listen**: IP address (or hostname) and port that Patroni will listen to for the REST API - to provide also the same health checks and cluster messaging between the participating nodes, as described above. to provide health-check information for HAProxy (or any other load balancer capable of doing a HTTP "OPTION" or "GET" checks).
 
--  **Optional**:
+        -  **authentication**: (optional)
-        -  **authentication**:
             -  **username**: Basic-auth username to protect unsafe REST API endpoints.
             -  **password**: Basic-auth password to protect unsafe REST API endpoints.
-
+        -  **certfile**: (optional): Specifies the file with the certificate in the PEM format. If the certfile is not specified or is left empty, the API server will work without SSL.
-        -  **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**: (optional): Specifies the file with the secret key in the PEM format.
-        -  **keyfile**: Specifies the file with the secret key in the PEM format.
+        -  **cafile**: (optional): Specifies the file with the CA_BUNDLE with certificates of trusted CAs to use while verifying client certs.
-        -  **cafile**: Specifies the file with the CA_BUNDLE with certificates of trusted CAs to use while verifying client certs.
+        -  **verify\_client**: (optional): ``none`` (default), ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. When ``required`` is used, then client authentication succeeds, if the certificate signature verification succeeds.  For ``optional`` the client cert will only be checked for ``PUT``, ``POST``, ``PATCH``, and ``DELETE`` requests.
-        -  **verify\_client**: ``none``, ``optional`` or ``required``. When ``none`` REST API will not check client certificates. When ``required`` client certificates are required for all REST API calls. When ``optional`` client certificates are required for all unsafe REST API endpoints. If ``verify_client`` is set to ``optional`` or ``required`` basic-auth is not checked.
 
 .. _patronictl_settings:
 
 CTL
 ---
--  **Optional**:
+- **ctl**: (optional)
     -  **insecure**: Allow connections to REST API without verifying SSL certs.
     -  **cacert**: Specifies the file with the CA_BUNDLE file or directory with certificates of trusted CAs to use while verifying REST API SSL certs. If not provided patronictl will use the value provided for REST API "cafile" parameter.
     -  **certfile**: Specifies the file with the client certificate in the PEM format. If not provided patronictl will use the value provided for REST API "certfile" parameter.

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
+- max_timelines_history: 0
 - check_timeline: false
 - postgresql.use_slots: true
 

docs/releases.rst

@@ -3,6 +3,122 @@
 Release notes
 =============
 
+Version 1.6.5
+-------------
+
+**New features**
+
+- Master stop timeout (Krishna Sarabu)
+
+  The number of seconds Patroni is allowed to wait when stopping Postgres. Effective only when ``synchronous_mode`` is enabled. When set to value greater than 0 and the ``synchronous_mode`` is enabled, Patroni sends ``SIGKILL`` to the postmaster if the stop operation is running for more than the value set by ``master_stop_timeout``. Set the value according to your durability/availability tradeoff. If the parameter is not set or set to non-positive value, ``master_stop_timeout`` does not have an effect.
+
+- Don't create permanent physical slot with name of the primary (Alexander Kukushkin)
+
+  It is a common problem that the primary recycles WAL segments while the replica is down. Now we have a good solution for static clusters, with a fixed number of nodes and names that never change. You just need to list the names of all nodes in the ``slots`` so the primary will not remove the slot when the node is down (not registered in DCS).
+
+- First draft of Config Validator (Igor Yanchenko)
+
+  Use ``patroni --validate-config patroni.yaml`` in order to validate Patroni configuration.
+
+- Possibility to configure max length of timelines history (Krishna)
+
+  Patroni writes the history of failovers/switchovers into the ``/history`` key in DCS. Over time the size of this key becomes big, but in most cases only the last few lines are interesting. The ``max_timelines_history`` parameter allows to specify the maximum number of timeline history items to be kept in DCS.
+
+- Kazoo 2.7.0 compatibility (Danyal Prout)
+
+  Some non-public methods in Kazoo changed their signatures, but Patroni was relying on them.
+
+
+**Improvements in patronictl**
+
+- Show member tags (Kostiantyn Nemchenko, Alexander)
+
+  Tags are configured individually for every node and there was no easy way to get an overview of them
+
+- Improve members output (Alexander)
+
+  The redundant cluster name won't be shown anymore on every line, only in the table header.
+
+.. code-block:: bash
+
+    $ patronictl list
+    + Cluster: batman (6813309862653668387) +---------+----+-----------+---------------------+
+    |    Member   |      Host      |  Role  |  State  | TL | Lag in MB | Tags                |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+    | postgresql0 | 127.0.0.1:5432 | Leader | running |  3 |           | clonefrom: true     |
+    |             |                |        |         |    |           | noloadbalance: true |
+    |             |                |        |         |    |           | nosync: true        |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+    | postgresql1 | 127.0.0.1:5433 |        | running |  3 |       0.0 |                     |
+    +-------------+----------------+--------+---------+----+-----------+---------------------+
+
+- Fail if a config file is specified explicitly but not found (Kaarel Moppel)
+
+  Previously ``patronictl`` was only reporting a ``DEBUG`` message.
+
+- Solved the problem of not initialized K8s pod breaking patronictl (Alexander)
+
+  Patroni is relying on certain pod annotations on K8s. When one of the Patroni pods is stopping or starting there is no valid annotation yet and ``patronictl`` was failing with an exception.
+
+
+**Stability improvements**
+
+- Apply 1 second backoff if LIST call to K8s API server failed (Alexander)
+
+  It is mostly necessary to avoid flooding logs, but also helps to prevent starvation of the main thread.
+
+- Retry if the ``retry-after`` HTTP header is returned by K8s API (Alexander)
+
+  If the K8s API server is overwhelmed with requests it might ask to retry.
+
+- Scrub ``KUBERNETES_`` environment from the postmaster (Feike Steenbergen)
+
+  The ``KUBERNETES_`` environment variables are not required for PostgreSQL, yet having them exposed to the postmaster will also expose them to backends and to regular database users (using pl/perl for example).
+
+- Clean up tablespaces on reinitialize (Krishna)
+
+  During reinit, Patroni was removing only ``PGDATA`` and leaving user-defined tablespace directories. This is causing Patroni to loop in reinit. The previous workarond for the problem was implementing the :ref:`custom bootstrap <custom_bootstrap>` script.
+
+- Explicitly execute ``CHECKPOINT`` after promote happened (Alexander)
+
+  It helps to reduce the time before the new primary is usable for ``pg_rewind``.
+
+- Smart refresh of Etcd members (Alexander)
+
+  In case Patroni failed to execute a request on all members of the Etcd cluster, Patroni will re-check ``A`` or ``SRV`` records for changes of IPs/hosts before retrying the next time.
+
+- Skip missing values from ``pg_controldata`` (Feike)
+
+  Values are missing when trying to use binaries of a version that doesn't match PGDATA. Patroni will try to start Postgres anyway, and Postgres will complain that the major version doesn't match and abort with an error.
+
+
+**Bugfixes**
+
+- Disable SSL verification for Consul when required (Julien Riou)
+
+  Starting from a certain version of ``urllib3``, the ``cert_reqs`` must be explicitly set to ``ssl.CERT_NONE`` in order to effectively disable SSL verification.
+
+- Avoid opening replication connection on every cycle of HA loop (Alexander)
+
+  Regression was introduced in 1.6.4.
+
+- Call ``on_role_change`` callback on failed primary (Alexander)
+
+  In certain cases it could lead to the virtual IP remaining attached to the old primary. Regression was introduced in 1.4.5.
+
+- Reset rewind state if postgres started after successful pg_rewind (Alexander)
+
+  As a result of this bug Patroni was starting up manually shut down postgres in the pause mode.
+
+- Convert ``recovery_min_apply_delay`` to ``ms`` when checking ``recovery.conf``
+
+  Patroni was indefinitely restarting replica if ``recovery_min_apply_delay`` was configured on PostgreSQL older than 12.
+
+- PyInstaller compatibility (Alexander)
+
+  PyInstaller freezes (packages) Python applications into stand-alone executables. The compatibility was broken when we switched to the ``spawn`` method instead of ``fork`` for ``multiprocessing``.
+
+
 Version 1.6.4
 -------------
 

docs/rest_api.rst

@@ -299,7 +299,10 @@ Example: schedule a switchover from the leader to any other healthy replica in t
 
 Depending on the situation the request might finish with a different HTTP status code and body. The status code **200** is returned when the switchover or failover successfully completed. If the switchover was successfully scheduled, Patroni will return HTTP status code **202**. In case something went wrong, the error status code (one of **400**, **412** or **503**) will be returned with some details in the response body. For more information please check the source code of ``patroni/api.py:do_POST_failover()`` method.
 
-The switchover and failover endpoints are used by ``patronictl switchover`` and ``patronictl failover``, respectively.
+- ``DELETE /switchover``: delete the scheduled switchover
+
+The ``POST /switchover`` and ``POST failover`` endpoints are used by ``patronictl switchover`` and ``patronictl failover``, respectively.
+The ``DELETE /switchover`` is used by ``patronictl flush <cluster-name> switchover``.
 
 
 Restart endpoint
@@ -315,7 +318,7 @@ Restart endpoint
 
 - ``DELETE /restart``: delete the scheduled restart
 
-``POST /restart`` and ``DELETE /restart`` endpoints are used by ``patronictl restart`` and ``patronictl flush`` respectively.
+``POST /restart`` and ``DELETE /restart`` endpoints are used by ``patronictl restart`` and ``patronictl flush <cluster-name> restart`` respectively.
 
 
 Reload endpoint

features/patroni_api.feature

@@ -8,6 +8,8 @@ Scenario: check API requests on a stand-alone server
 	Then I receive a response code 200
 	And I receive a response state running
 	And I receive a response role master
+	When I issue a GET request to http://127.0.0.1:8008/standby_leader
+	Then I receive a response code 503
 	When I issue a GET request to http://127.0.0.1:8008/health
 	Then I receive a response code 200
 	When I issue a GET request to http://127.0.0.1:8008/replica

features/standby_cluster.feature

@@ -26,7 +26,7 @@ Feature: standby cluster
     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
+    Then I receive a response code 503
     When I issue a GET request to http://127.0.0.1:8009/standby_leader
     Then I receive a response code 200
     And I receive a response role standby_leader
@@ -40,7 +40,7 @@ Feature: standby cluster
     And I kill postmaster on postgres1
     Then postgres2 is replicating from postgres0 after 32 seconds
     When I issue a GET request to http://127.0.0.1:8010/master
-    Then I receive a response code 200
+    Then I receive a response code 503
     When I issue a GET request to http://127.0.0.1:8010/standby_leader
     Then I receive a response code 200
     And I receive a response role standby_leader

features/steps/standby_cluster.py

@@ -10,7 +10,8 @@ SELECT * FROM pg_catalog.pg_stat_replication
 WHERE application_name = '{0}'
 """
 
-callback = sys.executable + " features/callback2.py "
+executable = sys.executable if os.name != 'nt' else sys.executable.replace('\\', '/')
+callback = executable + " features/callback2.py "
 
 
 @step('I start {name:w} with callback configured')
@@ -18,7 +19,7 @@ def start_patroni_with_callbacks(context, name):
     return context.pctl.start(name, custom_config={
         "postgresql": {
             "callbacks": {
-                "on_role_change": sys.executable + " features/callback.py"
+                "on_role_change": executable + " features/callback.py"
             }
         }
     })
@@ -31,7 +32,7 @@ def start_patroni(context, name, cluster_name):
         "postgresql": {
             "callbacks": {c: callback + name for c in ('on_start', 'on_stop', 'on_restart', 'on_role_change')},
             "backup_restore": {
-                "command": (sys.executable + " features/backup_restore.py --sourcedir=" +
+                "command": (executable + " features/backup_restore.py --sourcedir=" +
                             os.path.join(context.pctl.patroni_path, 'data', 'basebackup'))}
         }
     })

patroni/api.py

@@ -89,23 +89,32 @@ class RestApiHandler(BaseHTTPRequestHandler):
         patroni = self.server.patroni
         cluster = patroni.dcs.cluster
 
-        if not cluster and patroni.ha.is_paused():
-            primary_status_code = 200 if response['role'] == 'master' else 503
-        else:
-            primary_status_code = 200 if patroni.ha.is_leader() else 503
-
         replica_status_code = 200 if not patroni.noloadbalance and \
             response.get('role') == 'replica' and response.get('state') == 'running' else 503
+
+        if not cluster and patroni.ha.is_paused():
+            primary_status_code = 200 if response.get('role') == 'master' else 503
+            standby_leader_status_code = 200 if response.get('role') == 'standby_leader' else 503
+        elif patroni.ha.is_leader():
+            if patroni.ha.is_standby_cluster():
+                primary_status_code = replica_status_code = 503
+                standby_leader_status_code = 200 if response.get('role') in ('replica', 'standby_leader') else 503
+            else:
+                primary_status_code = 200
+                standby_leader_status_code = 503
+        else:
+            primary_status_code = standby_leader_status_code = 503
+
         status_code = 503
 
-        if patroni.ha.is_standby_cluster() and ('standby_leader' in path or 'standby-leader' in path):
+        if 'standby_leader' in path or 'standby-leader' in path:
-            status_code = 200 if patroni.ha.is_leader() else 503
+            status_code = standby_leader_status_code
         elif 'master' in path or 'leader' in path or 'primary' in path or 'read-write' in path:
             status_code = primary_status_code
         elif 'replica' in path:
             status_code = replica_status_code
         elif 'read-only' in path:
-            status_code = 200 if primary_status_code == 200 else replica_status_code
+            status_code = 200 if 200 in (primary_status_code, standby_leader_status_code) else replica_status_code
         elif 'health' in path:
             status_code = 200 if response.get('state') == 'running' else 503
         elif cluster:  # dcs is available
@@ -118,7 +127,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
         if write_status_code_only:  # when haproxy sends OPTIONS request it reads only status code and nothing more
             message = self.responses[status_code][0]
-            self.wfile.write('{0} {1} {2}\r\n'.format(self.protocol_version, status_code, message).encode('utf-8'))
+            self.wfile.write('{0} {1} {2}\r\n\r\n'.format(self.protocol_version, status_code, message).encode('utf-8'))
         else:
             self._write_status_response(status_code, response)
 
@@ -134,7 +143,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
         self._write_status_response(200, response)
 
     def do_GET_cluster(self):
-        cluster = self.server.patroni.dcs.cluster or self.server.patroni.dcs.get_cluster()
+        cluster = self.server.patroni.dcs.get_cluster(True)
         self._write_json_response(200, cluster_as_json(cluster))
 
     def do_GET_history(self):
@@ -283,6 +292,20 @@ class RestApiHandler(BaseHTTPRequestHandler):
             code = 404
         self._write_response(code, data)
 
+    @check_auth
+    def do_DELETE_switchover(self):
+        failover = self.server.patroni.dcs.get_cluster().failover
+        if failover and failover.scheduled_at:
+            if not self.server.patroni.dcs.manual_failover('', '', index=failover.index):
+                return self.send_error(409)
+            else:
+                data = "scheduled switchover deleted"
+                code = 200
+        else:
+            data = "no switchover is scheduled"
+            code = 404
+        self._write_response(code, data)
+
     @check_auth
     def do_POST_reinitialize(self):
         request = self._read_json_content(body_is_optional=True)
@@ -418,64 +441,55 @@ class RestApiHandler(BaseHTTPRequestHandler):
         return retry(self.server.query, sql, *params)
 
     def get_postgresql_status(self, retry=False):
+        postgresql = self.server.patroni.postgresql
         try:
             cluster = self.server.patroni.dcs.cluster
 
-            if self.server.patroni.postgresql.state not in ('running', 'restarting', 'starting'):
+            if postgresql.state not in ('running', 'restarting', 'starting'):
                 raise RetryFailedError('')
-            stmt = ("SELECT pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
+            stmt = ("SELECT " + postgresql.POSTMASTER_START_TIME + ", " + postgresql.TL_LSN + ","
-                    " CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0"
-                    " ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
-                    "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END,"
-                    " CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0"
-                    " ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint END,"
-                    " pg_catalog.pg_{0}_{1}_diff(COALESCE(pg_catalog.pg_last_{0}_receive_{1}(),"
-                    " pg_catalog.pg_last_{0}_replay_{1}()), '0/0')::bigint,"
-                    " pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint,"
                     " pg_catalog.to_char(pg_catalog.pg_last_xact_replay_timestamp(), 'YYYY-MM-DD HH24:MI:SS.MS TZ'),"
-                    " pg_catalog.pg_is_in_recovery() AND pg_catalog.pg_is_{0}_replay_paused(), "
                     " pg_catalog.array_to_json(pg_catalog.array_agg(pg_catalog.row_to_json(ri))) "
                     "FROM (SELECT (SELECT rolname FROM pg_authid WHERE oid = usesysid) AS usename,"
                     " application_name, client_addr, w.state, sync_state, sync_priority"
                     " FROM pg_catalog.pg_stat_get_wal_senders() w, pg_catalog.pg_stat_get_activity(pid)) AS ri")
 
-            row = self.query(stmt.format(self.server.patroni.postgresql.wal_name,
+            row = self.query(stmt.format(postgresql.wal_name, postgresql.lsn_name), retry=retry)[0]
-                                         self.server.patroni.postgresql.lsn_name), retry=retry)[0]
 
             result = {
-                'state': self.server.patroni.postgresql.state,
+                'state': postgresql.state,
                 'postmaster_start_time': row[0],
                 'role': 'replica' if row[1] == 0 else 'master',
-                'server_version': self.server.patroni.postgresql.server_version,
+                'server_version': postgresql.server_version,
                 'cluster_unlocked': bool(not cluster or cluster.is_unlocked()),
                 'xlog': ({
-                    'received_location': row[3],
+                    'received_location': row[4] or row[3],
-                    'replayed_location': row[4],
+                    'replayed_location': row[3],
-                    'replayed_timestamp': row[5],
+                    'replayed_timestamp': row[6],
-                    'paused': row[6]} if row[1] == 0 else {
+                    'paused': row[5]} if row[1] == 0 else {
                     'location': row[2]
                 })
             }
 
             if result['role'] == 'replica' and self.server.patroni.ha.is_standby_cluster():
-                result['role'] = self.server.patroni.postgresql.role
+                result['role'] = postgresql.role
 
             if row[1] > 0:
                 result['timeline'] = row[1]
             else:
                 leader_timeline = None if not cluster or cluster.is_unlocked() else cluster.leader.timeline
-                result['timeline'] = self.server.patroni.postgresql.replica_cached_timeline(leader_timeline)
+                result['timeline'] = postgresql.replica_cached_timeline(leader_timeline)
 
             if row[7]:
                 result['replication'] = row[7]
 
             return result
         except (psycopg2.Error, RetryFailedError, PostgresConnectionException):
-            state = self.server.patroni.postgresql.state
+            state = postgresql.state
             if state == 'running':
                 logger.exception('get_postgresql_status')
                 state = 'unknown'
-            return {'state': state, 'role': self.server.patroni.postgresql.role}
+            return {'state': state, 'role': postgresql.role}
 
     def log_message(self, fmt, *args):
         logger.debug("API thread: %s - - [%s] %s", self.client_address[0], self.log_date_time_string(), fmt % args)
@@ -525,10 +539,10 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
             if self.__protocol == 'https' and self.__ssl_options.get('verify_client') in ('required', 'optional'):
                 return rh._write_response(403, 'client certificate required')
 
-            reason = self.check_auth_header(rh.headers.get('Authorization'))
+        reason = self.check_auth_header(rh.headers.get('Authorization'))
-            if reason:
+        if reason:
-                headers = {'WWW-Authenticate': 'Basic realm="' + self.patroni.__class__.__name__ + '"'}
+            headers = {'WWW-Authenticate': 'Basic realm="' + self.patroni.__class__.__name__ + '"'}
-                return rh._write_response(401, reason, headers=headers)
+            return rh._write_response(401, reason, headers=headers)
         return True
 
     @staticmethod
@@ -599,6 +613,23 @@ class RestApiServer(ThreadingMixIn, HTTPServer, Thread):
         if reloading_config:
             self.start()
 
+    def process_request_thread(self, request, client_address):
+        if isinstance(request, tuple):
+            sock, newsock = request
+            try:
+                request = sock.context.wrap_socket(newsock, do_handshake_on_connect=sock.do_handshake_on_connect,
+                                                   suppress_ragged_eofs=sock.suppress_ragged_eofs, server_side=True)
+            except socket.error:
+                return
+        super(RestApiServer, self).process_request_thread(request, client_address)
+
+    def get_request(self):
+        sock = self.socket
+        newsock, addr = socket.socket.accept(sock)
+        if hasattr(sock, 'context'):  # SSLSocket, we want to do the deferred handshake from a thread
+            newsock = (sock, newsock)
+        return newsock, addr
+
     def reload_config(self, config):
         if 'listen' not in config:  # changing config in runtime
             raise ValueError('Can not find "restapi.listen" config')

patroni/config.py

@@ -22,7 +22,9 @@ _AUTH_ALLOWED_PARAMETERS = (
     'sslcert',
     'sslkey',
     'sslrootcert',
-    'sslcrl'
+    'sslcrl',
+    'gssencmode',
+    'channel_binding'
 )
 
 

patroni/ctl.py

@@ -24,6 +24,7 @@ import time
 import yaml
 
 from click import ClickException
+from collections import defaultdict
 from contextlib import contextmanager
 from patroni.dcs import get_dcs as _get_dcs
 from patroni.exceptions import PatroniException
@@ -181,14 +182,14 @@ def print_output(columns, rows, alignment=None, fmt='pretty', header=None, delim
         elements = [{k: v for k, v in zip(columns, r) if not header or str(v)} for r in rows]
         func = json.dumps if fmt == 'json' else format_config_for_editing
         click.echo(func(elements))
-    elif fmt in {'pretty', 'tsv'}:
+    elif fmt in {'pretty', 'tsv', 'topology'}:
         list_cluster = bool(header and columns and columns[0] == 'Cluster')
         if list_cluster and 'Tags' in columns:  # we want to format member tags as YAML
             i = columns.index('Tags')
             for row in rows:
                 if row[i]:
-                    row[i] = format_config_for_editing(row[i], fmt == 'tsv').strip()
+                    row[i] = format_config_for_editing(row[i], fmt != 'pretty').strip()
-        if list_cluster and fmt == 'pretty':  # skip cluster name if pretty-printing
+        if list_cluster and fmt != 'tsv':  # skip cluster name if pretty-printing
             columns = columns[1:] if columns else []
             rows = [row[1:] for row in rows]
 
@@ -256,6 +257,15 @@ def get_any_member(cluster, role='master', member=None):
             return m
 
 
+def get_all_members_leader_first(cluster):
+    leader_name = cluster.leader.member.name if cluster.leader and cluster.leader.member.api_url else None
+    if leader_name:
+        yield cluster.leader.member
+    for member in cluster.members:
+        if member.api_url and member.name != leader_name:
+            yield member
+
+
 def get_cursor(cluster, connect_parameters, role='master', member=None):
     member = get_any_member(cluster, role=role, member=member)
     if member is None:
@@ -761,6 +771,33 @@ def switchover(obj, cluster_name, master, candidate, force, scheduled):
     _do_failover_or_switchover(obj, 'switchover', cluster_name, master, candidate, force, scheduled)
 
 
+def generate_topology(level, member, topology):
+    members = topology.get(member['name'], [])
+
+    if level > 0:
+        member['name'] = '{0}+ {1}'.format((' ' * (level - 1) * 2), member['name'])
+
+    if member['name']:
+        yield member
+
+    for member in members:
+        for member in generate_topology(level + 1, member, topology):
+            yield member
+
+
+def topology_sort(members):
+    topology = defaultdict(list)
+    leader = next((m for m in members if m['role'].endswith('leader')), {'name': None})
+    replicas = set(member['name'] for member in members if not member['role'].endswith('leader'))
+    for member in members:
+        if not member['role'].endswith('leader'):
+            parent = member.get('tags', {}).get('replicatefrom')
+            parent = parent if parent and parent != member['name'] and parent in replicas else leader['name']
+            topology[parent].append(member)
+    for member in generate_topology(0, leader, topology):
+        yield member
+
+
 def output_members(cluster, name, extended=False, fmt='pretty'):
     rows = []
     logging.debug(cluster)
@@ -775,14 +812,15 @@ def output_members(cluster, name, extended=False, fmt='pretty'):
     # Show Host as 'host:port' if somebody is running on non-standard port or two nodes are running on the same host
     members = [m for m in cluster['members'] if 'host' in m]
     append_port = any('port' in m and m['port'] != 5432 for m in members) or\
-        len(set(m['host'] for m in cluster['members'])) < len(members)
+        len(set(m['host'] for m in members)) < len(members)
 
-    for m in cluster['members']:
+    sort = topology_sort if fmt == 'topology' else iter
+    for m in sort(cluster['members']):
         logging.debug(m)
 
         lag = m.get('lag', '')
-        m.update(cluster=name, member=m['name'], host=m.get('host'), tl=m.get('timeline', ''),
+        m.update(cluster=name, member=m['name'], host=m.get('host', ''), tl=m.get('timeline', ''),
-                 role='' if m['role'] == 'replica' else m['role'].replace('_', ' ').title(),
+                 role=m['role'].replace('_', ' ').title(),
                  lag_in_mb=round(lag/1024/1024) if isinstance(lag, six.integer_types) else lag,
                  pending_restart='*' if m.get('pending_restart') else '')
 
@@ -797,10 +835,10 @@ def output_members(cluster, name, extended=False, fmt='pretty'):
 
         rows.append([m.get(n.lower().replace(' ', '_'), '') for n in columns])
 
-    print_output(columns, rows, {'Lag in MB': 'r', 'TL': 'r', 'Tags': 'l'},
+    print_output(columns, rows, {'Member': 'l', 'Lag in MB': 'r', 'TL': 'r', 'Tags': 'l'},
                  fmt, ' Cluster: {0} ({1}) '.format(name, initialize))
 
-    if fmt != 'pretty':  # Omit service info when using machine-readable formats
+    if fmt not in ('pretty', 'topology'):  # Omit service info when using machine-readable formats
         return
 
     service_info = []
@@ -844,6 +882,16 @@ def members(obj, cluster_names, fmt, watch, w, extended, ts):
             output_members(cluster, cluster_name, extended, fmt)
 
 
+@ctl.command('topology', help='Prints ASCII topology for given cluster')
+@click.argument('cluster_names', nargs=-1)
+@option_watch
+@option_watchrefresh
+@click.pass_obj
+@click.pass_context
+def topology(ctx, obj, cluster_names, watch, w):
+    ctx.forward(members, fmt='topology')
+
+
 def timestamp(precision=6):
     return datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S.%f')[:precision - 7]
 
@@ -911,25 +959,45 @@ def scaffold(obj, cluster_name, sysid):
     click.echo("Cluster {0} has been created successfully".format(cluster_name))
 
 
-@ctl.command('flush', help='Discard scheduled events (restarts only currently)')
+@ctl.command('flush', help='Discard scheduled events')
 @click.argument('cluster_name')
 @click.argument('member_names', nargs=-1)
-@click.argument('target', type=click.Choice(['restart']))
+@click.argument('target', type=click.Choice(['restart', 'switchover']))
 @click.option('--role', '-r', help='Flush only members with this role', default='any',
               type=click.Choice(['master', 'replica', 'any']))
 @option_force
 @click.pass_obj
 def flush(obj, cluster_name, member_names, force, role, target):
-    cluster = get_dcs(obj, cluster_name).get_cluster()
+    dcs = get_dcs(obj, cluster_name)
+    cluster = dcs.get_cluster()
 
-    members = get_members(cluster, cluster_name, member_names, role, force, 'flush')
+    if target == 'restart':
-    for member in members:
+        for member in get_members(cluster, cluster_name, member_names, role, force, 'flush'):
-        if target == 'restart':
             if member.data.get('scheduled_restart'):
                 r = request_patroni(member, 'delete', 'restart')
                 check_response(r, member.name, 'flush scheduled restart')
             else:
                 click.echo('No scheduled restart for member {0}'.format(member.name))
+    elif target == 'switchover':
+        failover = cluster.failover
+        if not failover or not failover.scheduled_at:
+            return click.echo('No pending scheduled switchover')
+        for member in get_all_members_leader_first(cluster):
+            try:
+                r = request_patroni(member, 'delete', 'switchover')
+                if r.status in (200, 404):
+                    prefix = 'Success' if r.status == 200 else 'Failed'
+                    return click.echo('{0}: {1}'.format(prefix, r.data.decode('utf-8')))
+            except Exception as err:
+                logging.warning(str(err))
+                logging.warning('Member %s is not accessible', member.name)
+
+            click.echo('Failed: member={0}, status_code={1}, ({2})'.format(
+                member.name, r.status, r.data.decode('utf-8')))
+
+        logging.warning('Failing over to DCS')
+        click.echo('{0} Could not find any accessible member of cluster {1}'.format(timestamp(), cluster_name))
+        dcs.manual_failover('', '', index=failover.index)
 
 
 def wait_until_pause_is_applied(dcs, paused, old_cluster):
@@ -956,12 +1024,7 @@ def toggle_pause(config, cluster_name, paused, wait):
     if cluster.is_paused() == paused:
         raise PatroniCtlException('Cluster is {0} paused'.format(paused and 'already' or 'not'))
 
-    members = []
+    for member in get_all_members_leader_first(cluster):
-    if cluster.leader:
-        members.append(cluster.leader.member)
-    members.extend([m for m in cluster.members if m.api_url and (not members or members[0].name != m.name)])
-
-    for member in members:
         try:
             r = request_patroni(member, 'patch', 'config', {'pause': paused or None})
         except Exception as err:
@@ -1023,7 +1086,7 @@ def show_diff(before_editing, after_editing):
     If the output is to a tty the diff will be colored. Inputs are expected to be unicode strings.
     """
     def listify(string):
-        return [l+'\n' for l in string.rstrip('\n').split('\n')]
+        return [line + '\n' for line in string.rstrip('\n').split('\n')]
 
     unified_diff = difflib.unified_diff(listify(before_editing), listify(after_editing))
 

patroni/dcs/__init__.py

@@ -341,6 +341,10 @@ class ClusterConfig(namedtuple('ClusterConfig', 'index,data,modify_index')):
                 self.data.get('permanent_slots') or self.data.get('slots')
         ) or {}
 
+    @property
+    def max_timelines_history(self):
+        return self.data.get('max_timelines_history', 0)
+
 
 class SyncState(namedtuple('SyncState', 'index,leader,sync_standby')):
     """Immutable object (namedtuple) which represents last observed synhcronous replication state
@@ -638,7 +642,12 @@ class AbstractDCS(object):
            If the current node was running as a master and exception raised,
            instance would be demoted."""
 
-    def get_cluster(self):
+    def _bypass_caches(self):
+        """Used only in zookeeper"""
+
+    def get_cluster(self, force=False):
+        if force:
+            self._bypass_caches()
         try:
             cluster = self._load_cluster()
         except Exception:
@@ -754,10 +763,19 @@ class AbstractDCS(object):
         otherwise it should return `!False`"""
 
     @abc.abstractmethod
-    def delete_leader(self):
+    def _delete_leader(self):
-        """Voluntarily remove leader key from DCS
+        """Remove leader key from DCS.
         This method should remove leader key if current instance is the leader"""
 
+    def delete_leader(self, last_operation=None):
+        """Update optime/leader and voluntarily remove leader key from DCS.
+        This method should remove leader key if current instance is the leader.
+        :param last_operation: latest checkpoint location in bytes"""
+
+        if last_operation:
+            self.write_leader_optime(last_operation)
+        return self._delete_leader()
+
     @abc.abstractmethod
     def cancel_initialization(self):
         """ Removes the initialize key for a cluster """

patroni/dcs/consul.py

@@ -54,7 +54,7 @@ class HTTPClient(object):
         if ca_cert:
             kwargs['ca_certs'] = ca_cert
         kwargs['cert_reqs'] = ssl.CERT_REQUIRED if verify or ca_cert else ssl.CERT_NONE
-        self.http = urllib3.PoolManager(num_pools=10, **kwargs)
+        self.http = urllib3.PoolManager(num_pools=10, maxsize=10, **kwargs)
         self._ttl = None
 
     def set_read_timeout(self, timeout):
@@ -367,7 +367,11 @@ class Consul(AbstractDCS):
     def touch_member(self, data, permanent=False):
         cluster = self.cluster
         member = cluster and cluster.get_member(self._name, fallback_to_leader=False)
-        create_member = not permanent and self.refresh_session()
+
+        try:
+            create_member = not permanent and self.refresh_session()
+        except DCSError:
+            return False
 
         if member and (create_member or member.session != self._session):
             self._client.kv.delete(self.member_path)
@@ -503,7 +507,7 @@ class Consul(AbstractDCS):
         return self._client.kv.put(self.history_path, value)
 
     @catch_consul_errors
-    def delete_leader(self):
+    def _delete_leader(self):
         cluster = self.cluster
         if cluster and isinstance(cluster.leader, Leader) and cluster.leader.name == self._name:
             return self._client.kv.delete(self.leader_path, cas=cluster.leader.index)

patroni/dcs/etcd.py

@@ -11,6 +11,7 @@ import time
 
 from dns.exception import DNSException
 from dns import resolver
+from urllib3 import Timeout
 from urllib3.exceptions import HTTPError, ReadTimeoutError, ProtocolError
 from six.moves.queue import Queue
 from six.moves.http_client import HTTPException
@@ -69,6 +70,9 @@ class DnsCachingResolver(Thread):
     def resolve_async(self, host, port, attempt=0):
         self._resolve_queue.put(((host, port), attempt))
 
+    def remove(self, host, port):
+        self._cache.pop((host, port), None)
+
     @staticmethod
     def _do_resolve(host, port):
         try:
@@ -91,6 +95,7 @@ class Client(etcd.Client):
         # Workaround for the case when https://github.com/jplana/python-etcd/pull/196 is not applied
         self.http.connection_pool_kw.pop('ssl_version', None)
         self._config = config
+        self._initial_machines_cache = []
         self._load_machines_cache()
         self._allow_reconnect = True
         # allow passing retry argument to api_execute in params
@@ -98,14 +103,13 @@ class Client(etcd.Client):
         self._read_options.add('retry')
         self._del_conditions.add('retry')
 
-    def _calculate_timeouts(self, etcd_nodes=None, timeout=None):
+    def _calculate_timeouts(self, etcd_nodes, timeout=None):
         """Calculate a request timeout and number of retries per single etcd node.
         In case if the timeout per node is too small (less than one second) we will reduce the number of nodes.
         For the cluster with only one node we will try to do 2 retries.
         For clusters with 2 nodes we will try to do 1 retry for every node.
         No retries for clusters with 3 or more nodes. We better rely on switching to a different node."""
 
-        etcd_nodes = etcd_nodes or len(self._machines_cache) + 1
         per_node_timeout = timeout = float(timeout or self.read_timeout)
 
         max_retries = 4 - min(etcd_nodes, 3)
@@ -130,19 +134,25 @@ class Client(etcd.Client):
         basic_auth = ':'.join((self.username, self.password)) if self.username and self.password else None
         return urllib3.make_headers(basic_auth=basic_auth, user_agent=USER_AGENT)
 
-    def _build_request_parameters(self, timeout=None):
+    def _build_request_parameters(self, etcd_nodes, timeout=None):
         kwargs = {'headers': self._get_headers(), 'redirect': self.allow_redirect}
 
         if timeout is not None:
             kwargs.update(retries=0, timeout=timeout)
         else:
-            _, per_node_timeout, per_node_retries = self._calculate_timeouts()
+            _, per_node_timeout, per_node_retries = self._calculate_timeouts(etcd_nodes)
-            kwargs.update(timeout=per_node_timeout, retries=per_node_retries)
+            connect_timeout = max(1, per_node_timeout/2)
+            kwargs.update(timeout=Timeout(connect=connect_timeout, total=per_node_timeout), retries=per_node_retries)
         return kwargs
 
     def set_machines_cache_ttl(self, cache_ttl):
         self._machines_cache_ttl = cache_ttl
 
+    @property
+    def machines_cache(self):
+        base_uri, cache = self._base_uri, self._machines_cache
+        return ([base_uri] if base_uri in cache else []) + [machine for machine in cache if machine != base_uri]
+
     @property
     def machines(self):
         """Original `machines` method(property) of `etcd.Client` class raise exception
@@ -155,58 +165,58 @@ class Client(etcd.Client):
         Also this method implements the same timeout-retry logic as `api_execute`, because
         the original method was retrying 2 times with the `read_timeout` on each node."""
 
-        kwargs = self._build_request_parameters()
+        machines_cache = self.machines_cache
+        kwargs = self._build_request_parameters(len(machines_cache))
 
-        while True:
+        for base_uri in machines_cache:
             try:
-                response = self.http.request(self._MGET, self._base_uri + self.version_prefix + '/machines', **kwargs)
+                response = self.http.request(self._MGET, base_uri + self.version_prefix + '/machines', **kwargs)
                 data = self._handle_server_response(response).data.decode('utf-8')
                 machines = [m.strip() for m in data.split(',') if m.strip()]
                 logger.debug("Retrieved list of machines: %s", machines)
-                if not machines:
+                if machines:
-                    raise etcd.EtcdException
+                    random.shuffle(machines)
-                random.shuffle(machines)
+                    self._update_dns_cache(self._dns_resolver.resolve_async, machines)
-                for url in machines:
+                    return machines
-                    r = urlparse(url)
-                    port = r.port or (443 if r.scheme == 'https' else 80)
-                    self._dns_resolver.resolve_async(r.hostname, port)
-                return machines
             except Exception as e:
-                # We can't get the list of machines, if one server is in the
+                self.http.clear()
-                # machines cache, try on it
+                logger.error("Failed to get list of machines from %s%s: %r", base_uri, self.version_prefix, e)
-                logger.error("Failed to get list of machines from %s%s: %r", self._base_uri, self.version_prefix, e)
+
-                if self._machines_cache:
+        raise etcd.EtcdConnectionFailed('No more machines in the cluster')
-                    self._base_uri = self._machines_cache.pop(0)
-                    logger.info("Retrying on %s", self._base_uri)
-                elif self._update_machines_cache:
-                    raise etcd.EtcdException("Could not get the list of servers, "
-                                             "maybe you provided the wrong "
-                                             "host(s) to connect to?")
-                else:
-                    return []
 
     def set_read_timeout(self, timeout):
         self._read_timeout = timeout
 
-    def _do_http_request(self, request_executor, method, url, fields=None, **kwargs):
+    def _do_http_request(self, retry, machines_cache, request_executor, method, path, fields=None, **kwargs):
-        try:
+        some_request_failed = False
-            response = request_executor(method, url, fields=fields, **kwargs)
+        for i, base_uri in enumerate(machines_cache):
-            response.data.decode('utf-8')
+            if i > 0:
-            self._check_cluster_id(response)
+                logger.info("Retrying on %s", base_uri)
-        except (HTTPError, HTTPException, socket.error, socket.timeout) as e:
+            try:
-            if (isinstance(fields, dict) and fields.get("wait") == "true" and
+                response = request_executor(method, base_uri + path, fields=fields, **kwargs)
-                    isinstance(e, (ReadTimeoutError, ProtocolError))):
+                response.data.decode('utf-8')
-                logger.debug("Watch timed out.")
+                self._check_cluster_id(response)
+                if some_request_failed:
+                    self.set_base_uri(base_uri)
+                    self._refresh_machines_cache()
+                return response
+            except (HTTPError, HTTPException, socket.error, socket.timeout) as e:
+                self.http.clear()
                 # switch to the next etcd node because we don't know exactly what happened,
                 # whether the key didn't received an update or there is a network problem.
-                self._machines_cache.insert(0, self._base_uri)
+                if not retry and i + 1 < len(machines_cache):
-                self._base_uri = self._next_server()
+                    self.set_base_uri(machines_cache[i + 1])
-                raise etcd.EtcdWatchTimedOut("Watch timed out: {0}".format(e), cause=e)
+                if (isinstance(fields, dict) and fields.get("wait") == "true" and
-            logger.error("Request to server %s failed: %r", self._base_uri, e)
+                        isinstance(e, (ReadTimeoutError, ProtocolError))):
-            logger.info("Reconnection allowed, looking for another server.")
+                    logger.debug("Watch timed out.")
-            self._base_uri = self._next_server(cause=e)
+                    raise etcd.EtcdWatchTimedOut("Watch timed out: {0}".format(e), cause=e)
-            response = False
+                logger.error("Request to server %s failed: %r", base_uri, e)
-        return response
+                logger.info("Reconnection allowed, looking for another server.")
+                if not retry:
+                    raise etcd.EtcdException('{0} {1} request failed'.format(method, path))
+                some_request_failed = True
+
+        raise etcd.EtcdConnectionFailed('No more machines in the cluster')
 
     def api_execute(self, path, method, params=None, timeout=None):
         if not path.startswith('/'):
@@ -229,44 +239,34 @@ class Client(etcd.Client):
         elif not self._use_proxies and time.time() - self._machines_cache_updated > self._machines_cache_ttl:
             self._refresh_machines_cache()
 
-        kwargs.update(self._build_request_parameters(timeout))
+        machines_cache = self.machines_cache
-
+        etcd_nodes = len(machines_cache)
-        if retry:
+        kwargs.update(self._build_request_parameters(etcd_nodes, timeout))
-            machines_cache = [self._base_uri] + self._machines_cache
-
-        response = False
 
         while True:
             try:
-                some_request_failed = False
+                response = self._do_http_request(retry, machines_cache, request_executor, method, path, **kwargs)
-                while not response:
+                return self._handle_server_response(response)
-                    response = self._do_http_request(request_executor, method, self._base_uri + path, **kwargs)
+            except etcd.EtcdWatchTimedOut:
-
+                raise
-                    if response is False:
+            except etcd.EtcdConnectionFailed as ex:
-                        if not retry:
+                try:
-                            raise etcd.EtcdException('{0} {1} request failed'.format(method, path))
+                    if self._load_machines_cache():
-                        some_request_failed = True
+                        machines_cache = self.machines_cache
-                if some_request_failed:
+                        etcd_nodes = len(machines_cache)
-                    self._refresh_machines_cache()
+                except Exception as e:
-                if response:
+                    logger.debug('Failed to update list of etcd nodes: %r', e)
-                    break
-            except etcd.EtcdConnectionFailed:
-                if not retry:
-                    raise
                 sleeptime = retry.sleeptime
                 remaining_time = retry.stoptime - sleeptime - time.time()
-                nodes, timeout, retries = self._calculate_timeouts(len(machines_cache), remaining_time)
+                nodes, timeout, retries = self._calculate_timeouts(etcd_nodes, remaining_time)
                 if nodes == 0:
                     self._update_machines_cache = True
-                    raise
+                    raise ex
                 retry.sleep_func(sleeptime)
                 retry.update_delay()
-                # We still have some time left. Partially restore `_machines_cache` and retry request
+                # We still have some time left. Partially reduce `machines_cache` and retry request
-                kwargs.update(timeout=timeout, retries=retries)
+                kwargs.update(timeout=Timeout(connect=max(1, timeout/2), total=timeout), retries=retries)
-                self._base_uri = machines_cache[0]
+                machines_cache = machines_cache[:nodes]
-                self._machines_cache = machines_cache[1:nodes]
-
-        return self._handle_server_response(response)
 
     @staticmethod
     def get_srv_record(host):
@@ -327,6 +327,13 @@ class Client(etcd.Client):
             machines_cache = self._get_machines_cache_from_dns(self._config['host'], self._config['port'])
         return machines_cache
 
+    @staticmethod
+    def _update_dns_cache(func, machines):
+        for url in machines:
+            r = urlparse(url)
+            port = r.port or (443 if r.scheme == 'https' else 80)
+            func(r.hostname, port)
+
     def _load_machines_cache(self):
         """This method should fill up `_machines_cache` from scratch.
         It could happen only in two cases:
@@ -338,25 +345,49 @@ class Client(etcd.Client):
         if 'srv' not in self._config and 'host' not in self._config and 'hosts' not in self._config:
             raise Exception('Neither srv, hosts, host nor url are defined in etcd section of config')
 
-        self._machines_cache = self._get_machines_cache_from_config()
+        machines_cache = self._get_machines_cache_from_config()
-
         # Can not bootstrap list of etcd-cluster members, giving up
-        if not self._machines_cache:
+        if not machines_cache:
             raise etcd.EtcdException
 
-        # After filling up initial list of machines_cache we should ask etcd-cluster about actual list
+        # enforce resolving dns name,they might get new ips
-        self._base_uri = self._next_server()
+        self._update_dns_cache(self._dns_resolver.remove, machines_cache)
-        self._refresh_machines_cache()
-        self._update_machines_cache = False
 
-    def _refresh_machines_cache(self):
+        # The etcd cluster could change its topology over time and depending on how we resolve the initial
-        self._machines_cache = self._get_machines_cache_from_config() if self._use_proxies else self.machines
+        # topology (list of hosts in the Patroni config or DNS records, A or SRV) we might get into the situation
-        if self._base_uri in self._machines_cache:
+        # the the real topology doesn't match anymore with the topology resolved from the configuration file.
-            self._machines_cache.remove(self._base_uri)
+        # In case if the "initial" topology is the same as before we will not override the `_machines_cache`.
-        elif self._machines_cache:
+        ret = set(machines_cache) != set(self._initial_machines_cache)
-            self._base_uri = self._next_server()
+        if ret:
+            self._initial_machines_cache = self._machines_cache = machines_cache
+
+            # After filling up the initial list of machines_cache we should ask etcd-cluster about actual list
+            self._refresh_machines_cache(True)
+
+        self._update_machines_cache = False
+        return ret
+
+    def _refresh_machines_cache(self, updating_cache=False):
+        if self._use_proxies:
+            self._machines_cache = self._get_machines_cache_from_config()
+        else:
+            try:
+                self._machines_cache = self.machines
+            except etcd.EtcdConnectionFailed:
+                if updating_cache:
+                    raise etcd.EtcdException("Could not get the list of servers, "
+                                             "maybe you provided the wrong "
+                                             "host(s) to connect to?")
+                return
+
+        if self._base_uri not in self._machines_cache:
+            self.set_base_uri(self._machines_cache[0])
         self._machines_cache_updated = time.time()
 
+    def set_base_uri(self, value):
+        logger.info('Selected new etcd server %s', value)
+        self._base_uri = value
+
 
 class Etcd(AbstractDCS):
 
@@ -594,7 +625,7 @@ class Etcd(AbstractDCS):
         return self.retry(self._client.write, self.initialize_path, sysid, prevExist=(not create_new))
 
     @catch_etcd_errors
-    def delete_leader(self):
+    def _delete_leader(self):
         return self._client.delete(self.leader_path, prevValue=self._name)
 
     @catch_etcd_errors
@@ -633,7 +664,6 @@ class Etcd(AbstractDCS):
                     # than reestablishing http connection every time from every replica.
                     return True
                 except etcd.EtcdWatchTimedOut:
-                    self._client.http.clear()
                     self._has_failed = False
                     return False
                 except (etcd.EtcdEventIndexCleared, etcd.EtcdWatcherCleared):  # Watch failed

patroni/dcs/kubernetes.py

@@ -46,7 +46,7 @@ class CoreV1ApiProxy(object):
         self._api.api_client.user_agent = USER_AGENT
         self._api.api_client.rest_client.pool_manager.connection_pool_kw['maxsize'] = 10
         self._request_timeout = None
-        self._use_endpoints = use_endpoints
+        self._use_endpoints = bool(use_endpoints)
 
     def configure_timeouts(self, loop_wait, retry_timeout, ttl):
         # Normally every loop_wait seconds we should have receive something from the socket.
@@ -75,11 +75,15 @@ class CoreV1ApiProxy(object):
             try:
                 return getattr(self._api, func)(*args, **kwargs)
             except k8s_client.rest.ApiException as e:
-                if e.status in (502, 503, 504) or e.headers and 'retry-after' in e.headers:  # XXX
+                if e.status in (500, 503, 504) or e.headers and 'retry-after' in e.headers:  # XXX
                     raise KubernetesRetriableException(e)
                 raise
         return wrapper
 
+    @property
+    def use_endpoints(self):
+        return self._use_endpoints
+
 
 def catch_kubernetes_errors(func):
     def wrapper(*args, **kwargs):
@@ -98,7 +102,7 @@ def catch_kubernetes_errors(func):
 
 class ObjectCache(Thread):
 
-    def __init__(self, dcs, func, retry, condition):
+    def __init__(self, dcs, func, retry, condition, name=None):
         Thread.__init__(self)
         self.daemon = True
         self._api_client = k8s_client.ApiClient()
@@ -106,6 +110,7 @@ class ObjectCache(Thread):
         self._func = func
         self._retry = retry
         self._condition = condition
+        self._name = name  # name of this pod
         self._is_ready = False
         self._object_cache = {}
         self._object_cache_lock = Lock()
@@ -143,6 +148,10 @@ class ObjectCache(Thread):
         with self._object_cache_lock:
             return self._object_cache.copy()
 
+    def get(self, name):
+        with self._object_cache_lock:
+            return self._object_cache.get(name)
+
     def _build_cache(self):
         objects = self._list()
         return_type = 'V1' + objects.kind[:-4]
@@ -180,9 +189,14 @@ class ObjectCache(Thread):
                     if old_value:
                         old_value = (old_value.metadata.annotations or {}).get(self._annotations_map.get(name))
 
-                    if old_value != new_value and \
+                    value_changed = old_value != new_value and \
-                            (name != self._dcs.config_path or old_value is not None and new_value is not None):
+                        (name != self._dcs.config_path or old_value is not None and new_value is not None)
+
+                    if value_changed:
                         logger.debug('%s changed from %s to %s', name, old_value, new_value)
+
+                    # Do not wake up HA loop if we run as leader and received leader object update event
+                    if value_changed or name == self._dcs.leader_path and self._name != new_value:
                         self._dcs.event.set()
         finally:
             with self._condition:
@@ -223,24 +237,21 @@ class Kubernetes(AbstractDCS):
         except k8s_config.ConfigException:
             k8s_config.load_kube_config(context=config.get('context', 'local'))
 
-        self.__subsets = None
+        self.__my_pod = None
-        use_endpoints = config.get('use_endpoints') and (config.get('patronictl') or 'pod_ip' in config)
+        self.__ips = [] if config.get('patronictl') else [config.get('pod_ip')]
-        if use_endpoints:
+        self.__ports = []
-            addresses = [k8s_client.V1EndpointAddress(ip='127.0.0.1' if config.get('patronictl') else config['pod_ip'])]
+        for p in config.get('ports', [{}]):
-            ports = []
+            port = {'port': int(p.get('port', '5432'))}
-            for p in config.get('ports', [{}]):
+            port.update({n: p[n] for n in ('name', 'protocol') if p.get(n)})
-                port = {'port': int(p.get('port', '5432'))}
+            self.__ports.append(k8s_client.V1EndpointPort(**port))
-                port.update({n: p[n] for n in ('name', 'protocol') if p.get(n)})
+
-                ports.append(k8s_client.V1EndpointPort(**port))
+        self._api = CoreV1ApiProxy(config.get('use_endpoints'))
-            self.__subsets = [k8s_client.V1EndpointSubset(addresses=addresses, ports=ports)]
+        self._should_create_config_service = self._api.use_endpoints
-            self._should_create_config_service = True
-        self._api = CoreV1ApiProxy(use_endpoints)
         self.reload_config(config)
+        # leader_observed_record, leader_resource_version, and leader_observed_time are used only for leader race!
         self._leader_observed_record = {}
         self._leader_observed_time = None
         self._leader_resource_version = None
-        self._leader_observed_subsets = []
-        self._config_resource_version = None
         self.__do_not_watch = False
 
         self._condition = Condition()
@@ -251,7 +262,7 @@ class Kubernetes(AbstractDCS):
 
         kinds_func = functools.partial(self._api.list_namespaced_kind, self._namespace,
                                        label_selector=self._label_selector)
-        self._kinds = ObjectCache(self, kinds_func, self._retry, self._condition)
+        self._kinds = ObjectCache(self, kinds_func, self._retry, self._condition, self._name)
 
     def retry(self, *args, **kwargs):
         return self._retry.copy()(*args, **kwargs)
@@ -261,7 +272,7 @@ class Kubernetes(AbstractDCS):
 
     @property
     def leader_path(self):
-        return self._base_path[1:] if self.__subsets else super(Kubernetes, self).leader_path
+        return self._base_path[1:] if self._api.use_endpoints else super(Kubernetes, self).leader_path
 
     def set_ttl(self, ttl):
         ttl = int(ttl)
@@ -304,7 +315,6 @@ 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
@@ -322,7 +332,6 @@ class Kubernetes(AbstractDCS):
             leader = nodes.get(self.leader_path)
             metadata = leader and leader.metadata
             self._leader_resource_version = metadata.resource_version if metadata else None
-            self._leader_observed_subsets = leader.subsets if self.__subsets and leader and leader.subsets else []
             annotations = metadata and metadata.annotations or {}
 
             # get last leader operation
@@ -371,50 +380,71 @@ class Kubernetes(AbstractDCS):
         return p1.name == p2.name and p1.port == p2.port and (p1.protocol or 'TCP') == (p2.protocol or 'TCP')
 
     @staticmethod
-    def subsets_changed(last_observed_subsets, subsets):
+    def subsets_changed(last_observed_subsets, ip, ports):
         """
-        >>> Kubernetes.subsets_changed([], [])
+        >>> Kubernetes.subsets_changed([], None, [])
-        False
-        >>> Kubernetes.subsets_changed([], [k8s_client.V1EndpointSubset()])
         True
-        >>> s1 = [k8s_client.V1EndpointSubset(addresses=[k8s_client.V1EndpointAddress(ip='1.2.3.4')])]
+        >>> ip = '1.2.3.4'
-        >>> s2 = [k8s_client.V1EndpointSubset(addresses=[k8s_client.V1EndpointAddress(ip='1.2.3.5')])]
+        >>> a = [k8s_client.V1EndpointAddress(ip=ip)]
-        >>> Kubernetes.subsets_changed(s1, s2)
+        >>> s = [k8s_client.V1EndpointSubset(addresses=a)]
+        >>> Kubernetes.subsets_changed(s, '1.2.3.5', [])
         True
-        >>> a = [k8s_client.V1EndpointAddress(ip='1.2.3.4')]
+        >>> s = [k8s_client.V1EndpointSubset(addresses=a, ports=[k8s_client.V1EndpointPort(protocol='TCP', port=1)])]
-        >>> s1 = [k8s_client.V1EndpointSubset(addresses=a, ports=[k8s_client.V1EndpointPort(protocol='TCP', port=1)])]
+        >>> Kubernetes.subsets_changed(s, '1.2.3.4', [k8s_client.V1EndpointPort(port=5432)])
-        >>> s2 = [k8s_client.V1EndpointSubset(addresses=a, ports=[k8s_client.V1EndpointPort(port=5432)])]
-        >>> Kubernetes.subsets_changed(s1, s2)
         True
         >>> p1 = k8s_client.V1EndpointPort(name='port1', port=1)
         >>> p2 = k8s_client.V1EndpointPort(name='port2', port=2)
         >>> p3 = k8s_client.V1EndpointPort(name='port3', port=3)
-        >>> s1 = [k8s_client.V1EndpointSubset(addresses=a, ports=[p1, p2])]
+        >>> s = [k8s_client.V1EndpointSubset(addresses=a, ports=[p1, p2])]
-        >>> s2 = [k8s_client.V1EndpointSubset(addresses=a, ports=[p2, p3])]
+        >>> Kubernetes.subsets_changed(s, ip, [p2, p3])
-        >>> Kubernetes.subsets_changed(s1, s2)
         True
         >>> s2 = [k8s_client.V1EndpointSubset(addresses=a, ports=[p2, p1])]
-        >>> Kubernetes.subsets_changed(s1, s2)
+        >>> Kubernetes.subsets_changed(s, ip, [p2, p1])
         False
         """
-        if len(last_observed_subsets) != len(subsets):
+
+        if len(last_observed_subsets) != 1:
             return True
-        if subsets == []:
-            return False
         if len(last_observed_subsets[0].addresses or []) != 1 or \
-                last_observed_subsets[0].addresses[0].ip != subsets[0].addresses[0].ip or \
+                last_observed_subsets[0].addresses[0].ip != ip or \
-                len(last_observed_subsets[0].ports) != len(subsets[0].ports):
+                len(last_observed_subsets[0].ports) != len(ports):
             return True
-        if len(subsets[0].ports) == 1:
+        if len(ports) == 1:
-            return not Kubernetes.compare_ports(last_observed_subsets[0].ports[0], subsets[0].ports[0])
+            return not Kubernetes.compare_ports(last_observed_subsets[0].ports[0], ports[0])
         observed_ports = {p.name: p for p in last_observed_subsets[0].ports}
-        for p in subsets[0].ports:
+        for p in ports:
             if p.name not in observed_ports or not Kubernetes.compare_ports(p, observed_ports.pop(p.name)):
                 return True
         return False
 
-    @catch_kubernetes_errors
+    def __target_ref(self, leader_ip, latest_subsets, pod):
-    def patch_or_create(self, name, annotations, resource_version=None, patch=False, retry=True, subsets=None):
+        # we want to re-use existing target_ref if possible
+        for subset in latest_subsets:
+            for address in subset.addresses or []:
+                if address.ip == leader_ip and address.target_ref and address.target_ref.name == self._name:
+                    return address.target_ref
+        return k8s_client.V1ObjectReference(kind='Pod', uid=pod.metadata.uid, namespace=self._namespace,
+                                            name=self._name, resource_version=pod.metadata.resource_version)
+
+    def _map_subsets(self, endpoints, ips):
+        leader = self._kinds.get(self.leader_path)
+        latest_subsets = leader and leader.subsets or []
+        if not ips:
+            # We want to have subsets empty
+            if latest_subsets:
+                endpoints['subsets'] = []
+            return
+
+        pod = self._pods.get(self._name)
+        leader_ip = ips[0] or pod and pod.status.pod_ip
+        # don't touch subsets if our (leader) ip is unknown or subsets is valid
+        if leader_ip and self.subsets_changed(latest_subsets, leader_ip, self.__ports):
+            kwargs = {'hostname': pod.spec.hostname, 'node_name': pod.spec.node_name,
+                      'target_ref': self.__target_ref(leader_ip, latest_subsets, pod)} if pod else {}
+            address = k8s_client.V1EndpointAddress(ip=leader_ip, **kwargs)
+            endpoints['subsets'] = [k8s_client.V1EndpointSubset(addresses=[address], ports=self.__ports)]
+
+    def _patch_or_create(self, name, annotations, resource_version=None, patch=False, retry=None, ips=None):
         metadata = {'namespace': self._namespace, 'name': name, 'labels': self._labels, 'annotations': annotations}
         if patch or resource_version:
             if resource_version is not None:
@@ -426,27 +456,29 @@ class Kubernetes(AbstractDCS):
             metadata['annotations'] = {k: v for k, v in metadata['annotations'].items() if v is not None}
 
         metadata = k8s_client.V1ObjectMeta(**metadata)
-        if subsets is not None and self.__subsets:
+        if ips is not None and self._api.use_endpoints:
             endpoints = {'metadata': metadata}
-            if self.subsets_changed(self._leader_observed_subsets, subsets):
+            self._map_subsets(endpoints, ips)
-                endpoints['subsets'] = subsets
             body = k8s_client.V1Endpoints(**endpoints)
         else:
             body = k8s_client.V1ConfigMap(metadata=metadata)
-        ret = self.retry(func, self._namespace, body) if retry else func(self._namespace, body)
+        ret = retry(func, self._namespace, body) if retry else func(self._namespace, body)
         if ret:
             self._kinds.set(name, ret)
         return ret
 
+    @catch_kubernetes_errors
+    def patch_or_create(self, name, annotations, resource_version=None, patch=False, retry=True, ips=None):
+        if retry is True:
+            retry = self.retry
+        return self._patch_or_create(name, annotations, resource_version, patch, retry, ips)
+
     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:
+        if self._api.use_endpoints 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)
+        return 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)
@@ -465,20 +497,58 @@ class Kubernetes(AbstractDCS):
     def _update_leader(self):
         """Unused"""
 
+    def _update_leader_with_retry(self, annotations, resource_version, ips):
+        retry = self._retry.copy()
+
+        def _retry(*args, **kwargs):
+            return retry(*args, **kwargs)
+
+        try:
+            return self._patch_or_create(self.leader_path, annotations, resource_version, ips=ips, retry=_retry)
+        except k8s_client.rest.ApiException as e:
+            if e.status == 409:
+                logger.warning('Concurrent update of %s', self.leader_path)
+            else:
+                logger.exception('Permission denied' if e.status == 403 else 'Unexpected error from Kubernetes API')
+                return False
+        except RetryFailedError:
+            return False
+
+        deadline = retry.stoptime - time.time()
+        if deadline < 2:
+            return False
+
+        retry.sleep_func(1)  # Give a chance for ObjectCache to receive the latest version
+
+        kind = self._kinds.get(self.leader_path)
+        kind_annotations = kind and kind.metadata.annotations or {}
+        kind_resource_version = kind and kind.metadata.resource_version
+
+        # There is different leader or resource_version in cache didn't change
+        if kind and (kind_annotations.get(self._LEADER) != self._name or kind_resource_version == resource_version):
+            return False
+
+        retry.deadline = deadline - 1  # Update deadline and retry
+        return self.patch_or_create(self.leader_path, annotations, kind_resource_version, ips=ips, retry=_retry)
+
     def update_leader(self, last_operation, access_is_restricted=False):
+        kind = self._kinds.get(self.leader_path)
+        kind_annotations = kind and kind.metadata.annotations or {}
+
+        if kind and kind_annotations.get(self._LEADER) != self._name:
+            return False
+
         now = datetime.datetime.now(tzutc).isoformat()
+        leader_observed_record = kind_annotations or self._leader_observed_record
         annotations = {self._LEADER: self._name, 'ttl': str(self._ttl), 'renewTime': now,
-                       'acquireTime': self._leader_observed_record.get('acquireTime') or now,
+                       'acquireTime': leader_observed_record.get('acquireTime') or now,
-                       'transitions': self._leader_observed_record.get('transitions') or '0'}
+                       'transitions': leader_observed_record.get('transitions') or '0'}
         if last_operation:
             annotations[self._OPTIME] = last_operation
 
-        subsets = [] if access_is_restricted else self.__subsets
+        resource_version = kind and kind.metadata.resource_version
-
+        ips = [] if access_is_restricted else self.__ips
-        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=subsets)
+        return self._update_leader_with_retry(annotations, resource_version, ips)
-        if ret:
-            self._leader_resource_version = ret.metadata.resource_version
-        return ret
 
     def attempt_to_acquire_leader(self, permanent=False):
         now = datetime.datetime.now(tzutc).isoformat()
@@ -495,11 +565,9 @@ class Kubernetes(AbstractDCS):
             else:
                 annotations['acquireTime'] = self._leader_observed_record.get('acquireTime') or now
             annotations['transitions'] = str(transitions)
-        subsets = [] if self.__subsets else None
+        ips = [] if self._api.use_endpoints else None
-        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, subsets=subsets)
+        ret = self.patch_or_create(self.leader_path, annotations, self._leader_resource_version, ips=ips)
-        if ret:
+        if not ret:
-            self._leader_resource_version = ret.metadata.resource_version
-        else:
             logger.info('Could not take out TTL lock')
         return ret
 
@@ -515,6 +583,11 @@ class Kubernetes(AbstractDCS):
         patch = bool(self.cluster and isinstance(self.cluster.failover, Failover) and self.cluster.failover.index)
         return self.patch_or_create(self.failover_path, annotations, index, bool(index or patch), False)
 
+    @property
+    def _config_resource_version(self):
+        config = self._kinds.get(self.config_path)
+        return config and config.metadata.resource_version
+
     def set_config_value(self, value, index=None):
         return self.patch_or_create_config({self._CONFIG: value}, index, bool(self._config_resource_version), False)
 
@@ -537,7 +610,9 @@ 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:
+            if ret:
+                self._pods.set(self._name, ret)
+        if self._should_create_config_service:
             self._create_config_service()
         return ret
 
@@ -546,9 +621,16 @@ class Kubernetes(AbstractDCS):
         resource_version = cluster.config.index if cluster and cluster.config and cluster.config.index else None
         return self.patch_or_create_config({self._INITIALIZE: sysid}, resource_version)
 
-    def delete_leader(self):
+    def _delete_leader(self):
-        if self.cluster and isinstance(self.cluster.leader, Leader) and self.cluster.leader.name == self._name:
+        """Unused"""
-            self.patch_or_create(self.leader_path, {self._LEADER: None}, self._leader_resource_version, True, False, [])
+
+    def delete_leader(self, last_operation=None):
+        kind = self._kinds.get(self.leader_path)
+        if kind and (kind.metadata.annotations or {}).get(self._LEADER) == self._name:
+            annotations = {self._LEADER: None}
+            if last_operation:
+                annotations[self._OPTIME] = last_operation
+            self.patch_or_create(self.leader_path, annotations, kind.metadata.resource_version, True, False, [])
             self.reset_cluster()
 
     def cancel_initialization(self):
@@ -576,6 +658,6 @@ class Kubernetes(AbstractDCS):
             return True
 
         try:
-            return super(Kubernetes, self).watch(None, timeout)
+            return super(Kubernetes, self).watch(None, timeout + 0.5)
         finally:
             self.event.clear()

patroni/dcs/zookeeper.py

@@ -223,6 +223,9 @@ class ZooKeeper(AbstractDCS):
                 raise ZooKeeperError('ZooKeeper in not responding properly')
         return cluster
 
+    def _bypass_caches(self):
+        self._fetch_cluster = True
+
     def _create(self, path, value, retry=False, ephemeral=False):
         try:
             if retry:
@@ -315,7 +318,7 @@ class ZooKeeper(AbstractDCS):
     def _update_leader(self):
         return True
 
-    def delete_leader(self):
+    def _delete_leader(self):
         self._client.restart()
         return True
 

patroni/ha.py

@@ -198,6 +198,8 @@ class Ha(object):
                 try:
                     timeline, wal_position, pg_control_timeline = self.state_handler.timeline_wal_position()
                     data['xlog_location'] = wal_position
+                    if not timeline:  # try pg_stat_wal_receiver to get the timeline
+                        timeline = self.state_handler.received_timeline()
                     if not timeline:
                         # So far the only way to get the current timeline on the standby is from
                         # the replication connection. In order to avoid opening the replication
@@ -323,7 +325,7 @@ class Ha(object):
                 (self.cluster.is_unlocked() or self._rewind.can_rewind):
             self._crash_recovery_executed = True
             msg = 'doing crash recovery in a single user mode'
-            return self._async_executor.try_run_async(msg, self.state_handler.fix_cluster_state) or msg
+            return self._async_executor.try_run_async(msg, self._rewind.ensure_clean_shutdown) or msg
 
         self.load_cluster_from_dcs()
 
@@ -389,15 +391,22 @@ class Ha(object):
         if self.is_paused():
             if not (self._rewind.is_needed and self._rewind.can_rewind_or_reinitialize_allowed)\
                     or self.cluster.is_unlocked():
-                self.state_handler.set_role('master' if is_leader else 'replica')
                 if is_leader:
+                    self.state_handler.set_role('master')
                     return 'continue to run as master without lock'
-                elif not node_to_follow:
+                elif self.state_handler.role != 'standby_leader':
+                    self.state_handler.set_role('replica')
+
+                if not node_to_follow:
                     return 'no action'
         elif is_leader:
             self.demote('immediate-nolock')
             return demote_reason
 
+        if self.is_standby_cluster() and self._leader_timeline and \
+                self.state_handler.get_history(self._leader_timeline + 1):
+            self._rewind.trigger_check_diverged_lsn()
+
         msg = self._handle_rewind_or_reinitialize()
         if msg:
             return msg
@@ -415,6 +424,7 @@ class Ha(object):
                                                        self.state_handler.follow, args=(node_to_follow, role))
                 else:
                     self.state_handler.follow(node_to_follow, role, do_reload=True)
+                self._rewind.trigger_check_diverged_lsn()
             elif role == 'standby_leader' and self.state_handler.role != role:
                 self.state_handler.set_role(role)
                 self.state_handler.call_nowait(ACTION_ON_ROLE_CHANGE)
@@ -523,9 +533,10 @@ class Ha(object):
             if cluster_history:
                 self.dcs.set_history_value('[]')
         elif not cluster_history or cluster_history[-1][0] != master_timeline - 1 or len(cluster_history[-1]) != 4:
-            cluster_history = {l[0]: l for l in cluster_history or []}
+            cluster_history = {line[0]: line for line in cluster_history or []}
             history = self.state_handler.get_history(master_timeline)
-            if history:
+            if history and self.cluster.config:
+                history = history[-self.cluster.config.max_timelines_history:]
                 for line in history:
                     # enrich current history with promotion timestamps stored in DCS
                     if len(line) == 3 and line[0] in cluster_history \
@@ -747,13 +758,13 @@ class Ha(object):
 
         return self._is_healthiest_node(members.values())
 
-    def _delete_leader(self):
+    def _delete_leader(self, last_operation=None):
         self.set_is_leader(False)
-        self.dcs.delete_leader()
+        self.dcs.delete_leader(last_operation)
         self.dcs.reset_cluster()
 
-    def release_leader_key_voluntarily(self):
+    def release_leader_key_voluntarily(self, last_operation=None):
-        self._delete_leader()
+        self._delete_leader(last_operation)
         self.touch_member()
         logger.info("Leader key released")
 
@@ -783,8 +794,9 @@ class Ha(object):
         self.set_is_leader(False)
 
         if mode_control['release']:
+            checkpoint_location = self.state_handler.latest_checkpoint_location() if mode == 'graceful' else None
             with self._async_executor:
-                self.release_leader_key_voluntarily()
+                self.release_leader_key_voluntarily(checkpoint_location)
             time.sleep(2)  # Give a time to somebody to take the leader lock
         if mode_control['offline']:
             node_to_follow, leader = None, None
@@ -944,7 +956,7 @@ class Ha(object):
                     return msg
 
                 # check if the node is ready to be used by pg_rewind
-                self._rewind.check_for_checkpoint_after_promote()
+                self._rewind.ensure_checkpoint_after_promote(self.wakeup)
 
                 if self.is_standby_cluster():
                     # in case of standby cluster we don't really need to
@@ -1366,8 +1378,12 @@ class Ha(object):
 
     def run_cycle(self):
         with self._async_executor:
-            info = self._run_cycle()
+            try:
-            return (self.is_paused() and 'PAUSE: ' or '') + info
+                info = self._run_cycle()
+                return (self.is_paused() and 'PAUSE: ' or '') + info
+            except Exception:
+                logger.exception('Unexpected exception')
+                return 'Unexpected exception raised, please report it as a BUG'
 
     def shutdown(self):
         if self.is_paused():
@@ -1383,7 +1399,8 @@ class Ha(object):
                                                                         stop_timeout=self.master_stop_timeout()))
             if not self.state_handler.is_running():
                 if self.has_lock():
-                    self.dcs.delete_leader()
+                    checkpoint_location = self.state_handler.latest_checkpoint_location()
+                    self.dcs.delete_leader(checkpoint_location)
                 self.touch_member()
             else:
                 # XXX: what about when Patroni is started as the wrong user that has access to the watchdog device

patroni/postgresql/__init__.py

@@ -8,16 +8,18 @@ import time
 
 from contextlib import contextmanager
 from copy import deepcopy
+from dateutil import tz
+from datetime import datetime
 from patroni.postgresql.callback_executor import CallbackExecutor
 from patroni.postgresql.bootstrap import Bootstrap
 from patroni.postgresql.cancellable import CancellableSubprocess
-from patroni.postgresql.config import ConfigHandler
+from patroni.postgresql.config import ConfigHandler, mtime
 from patroni.postgresql.connection import Connection, get_connection_cursor
-from patroni.postgresql.misc import parse_history, postgres_major_version_to_int
+from patroni.postgresql.misc import parse_history, parse_lsn, postgres_major_version_to_int
 from patroni.postgresql.postmaster import PostmasterProcess
 from patroni.postgresql.slots import SlotsHandler
 from patroni.exceptions import PostgresConnectionException
-from patroni.utils import Retry, RetryFailedError, polling_loop, data_directory_is_empty
+from patroni.utils import Retry, RetryFailedError, polling_loop, data_directory_is_empty, parse_int
 from threading import current_thread, Lock
 from psutil import TimeoutExpired
 
@@ -46,6 +48,16 @@ def null_context():
 
 class Postgresql(object):
 
+    POSTMASTER_START_TIME = "pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ')"
+    TL_LSN = ("CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
+              "ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
+              "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END, "  # master timeline
+              "CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
+              "ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint END, "  # write_lsn
+              "pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint,  "
+              "pg_catalog.pg_{0}_{1}_diff(COALESCE(pg_catalog.pg_last_{0}_receive_{1}(), '0/0'), '0/0')::bigint, "
+              "pg_catalog.pg_is_in_recovery() AND pg_catalog.pg_is_{0}_replay_paused()")
+
     def __init__(self, config):
         self.name = config['name']
         self.scope = config['scope']
@@ -125,6 +137,10 @@ class Postgresql(object):
     def callback(self):
         return self.config.get('callbacks') or {}
 
+    @property
+    def wal_dir(self):
+        return os.path.join(self._data_dir, 'pg_' + self.wal_name)
+
     @property
     def wal_name(self):
         return 'wal' if self._major_version >= 100000 else 'xlog'
@@ -135,17 +151,17 @@ class Postgresql(object):
 
     @property
     def cluster_info_query(self):
-        pg_control_timeline = 'timeline_id FROM pg_catalog.pg_control_checkpoint()' \
+        if self._major_version >= 90600:
-                if self._major_version >= 90600 and self.role == 'standby_leader' else '0'
+            extra = (", CASE WHEN latest_end_lsn IS NULL THEN NULL ELSE received_tli END,"
-        return ("SELECT CASE WHEN pg_catalog.pg_is_in_recovery() THEN 0 "
+                     " slot_name, conninfo FROM pg_catalog.pg_stat_get_wal_receiver()")
-                "ELSE ('x' || pg_catalog.substr(pg_catalog.pg_{0}file_name("
+            if self.role == 'standby_leader':
-                "pg_catalog.pg_current_{0}_{1}()), 1, 8))::bit(32)::int END, "
+                extra = "timeline_id" + extra + ", pg_catalog.pg_control_checkpoint()"
-                "CASE WHEN pg_catalog.pg_is_in_recovery() THEN GREATEST("
+            else:
-                " pg_catalog.pg_{0}_{1}_diff(COALESCE("
+                extra = "0" + extra
-                "pg_catalog.pg_last_{0}_receive_{1}(), '0/0'), '0/0')::bigint,"
+        else:
-                " pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_last_{0}_replay_{1}(), '0/0')::bigint)"
+            extra = "0, NULL, NULL, NULL"
-                "ELSE pg_catalog.pg_{0}_{1}_diff(pg_catalog.pg_current_{0}_{1}(), '0/0')::bigint "
+
-                "END, {2}").format(self.wal_name, self.lsn_name, pg_control_timeline)
+        return ("SELECT " + self.TL_LSN + ", {2}").format(self.wal_name, self.lsn_name, extra)
 
     def _version_file_exists(self):
         return not self.data_directory_empty() and os.path.isfile(self._version_file)
@@ -290,7 +306,9 @@ class Postgresql(object):
         if not self._cluster_info_state:
             try:
                 result = self._is_leader_retry(self._query, self.cluster_info_query).fetchone()
-                self._cluster_info_state = dict(zip(['timeline', 'wal_position', 'pg_control_timeline'], result))
+                self._cluster_info_state = dict(zip(['timeline', 'wal_position', 'replayed_location',
+                                                     'received_location', 'replay_paused', 'pg_control_timeline',
+                                                     'received_tli', 'slot_name', 'conninfo'], result))
             except RetryFailedError as e:  # SELECT failed two times
                 self._cluster_info_state = {'error': str(e)}
                 if not self.is_starting() and self.pg_isready() == STATE_REJECT:
@@ -301,6 +319,21 @@ class Postgresql(object):
 
         return self._cluster_info_state.get(name)
 
+    def replayed_location(self):
+        return self._cluster_info_state_get('replayed_location')
+
+    def received_location(self):
+        return self._cluster_info_state_get('received_location')
+
+    def primary_slot_name(self):
+        return self._cluster_info_state_get('slot_name')
+
+    def primary_conninfo(self):
+        return self._cluster_info_state_get('conninfo')
+
+    def received_timeline(self):
+        return self._cluster_info_state_get('received_tli')
+
     def is_leader(self):
         return bool(self._cluster_info_state_get('timeline'))
 
@@ -310,6 +343,17 @@ class Postgresql(object):
         except (TypeError, ValueError):
             logger.exception('Failed to parse timeline from pg_controldata output')
 
+    def latest_checkpoint_location(self):
+        """Returns checkpoint location for the cleanly shut down primary"""
+
+        data = self.controldata()
+        lsn = data.get('Latest checkpoint location')
+        if data.get('Database cluster state') == 'shut down' and lsn:
+            try:
+                return str(parse_lsn(lsn))
+            except (IndexError, ValueError) as e:
+                logger.error('Exception when parsing lsn %s: %r', lsn, e)
+
     def is_running(self):
         """Returns PostmasterProcess if one is running on the data directory or None. If most recently seen process
         is running updates the cached process based on pid file."""
@@ -571,9 +615,9 @@ class Postgresql(object):
         except psycopg2.Error:
             pass
 
-    def reload(self):
+    def reload(self, block_callbacks=False):
         ret = self.pg_ctl('reload')
-        if ret:
+        if ret and not block_callbacks:
             self.call_nowait(ACTION_ON_RELOAD)
         return ret
 
@@ -653,9 +697,17 @@ class Postgresql(object):
             return False
         return True
 
+    def get_guc_value(self, name):
+        cmd = [self.pgcommand('postgres'), self._data_dir, '-C', name]
+        try:
+            data = subprocess.check_output(cmd)
+            if data:
+                return data.decode('utf-8').strip()
+        except Exception as e:
+            logger.error('Failed to execute %s: %r', cmd, e)
+
     def controldata(self):
         """ return the contents of pg_controldata, or non-True value if pg_controldata call failed """
-        result = {}
         # Don't try to call pg_controldata during backup restore
         if self._version_file_exists() and self.state != 'creating replica':
             try:
@@ -663,13 +715,12 @@ class Postgresql(object):
                 env.update(LANG='C', LC_ALL='C')
                 data = subprocess.check_output([self.pgcommand('pg_controldata'), self._data_dir], env=env)
                 if data:
-                    data = data.decode('utf-8').splitlines()
+                    data = filter(lambda e: ':' in e, data.decode('utf-8').splitlines())
-                    # pg_controldata output depends on major verion. Some of parameters are prefixed by 'Current '
+                    # pg_controldata output depends on major version. Some of parameters are prefixed by 'Current '
-                    result = {l.split(':')[0].replace('Current ', '', 1): l.split(':', 1)[1].strip() for l in data
+                    return {k.replace('Current ', '', 1): v.strip() for k, v in map(lambda e: e.split(':', 1), data)}
-                              if l and ':' in l}
             except subprocess.CalledProcessError:
                 logger.exception("Error when calling pg_controldata")
-        return result
+        return {}
 
     @contextmanager
     def get_replication_connection_cursor(self, host='localhost', port=5432, **kwargs):
@@ -679,18 +730,13 @@ class Postgresql(object):
         with get_connection_cursor(**conn_kwargs) as cur:
             yield cur
 
-    def get_local_timeline_lsn_from_replication_connection(self):
+    def get_replica_timeline(self):
-        timeline = lsn = None
         try:
             with self.get_replication_connection_cursor(**self.config.local_replication_address) as cur:
                 cur.execute('IDENTIFY_SYSTEM')
-                timeline, lsn = cur.fetchone()[1:3]
+                return cur.fetchone()[1]
         except Exception:
             logger.exception('Can not fetch local timeline and lsn from replication connection')
-        return timeline, lsn
-
-    def get_replica_timeline(self):
-        return self.get_local_timeline_lsn_from_replication_connection()[0]
 
     def replica_cached_timeline(self, master_timeline):
         if not self._cached_replica_timeline or not master_timeline or self._cached_replica_timeline != master_timeline:
@@ -701,19 +747,19 @@ class Postgresql(object):
         return self._cluster_info_state_get('timeline')
 
     def get_history(self, timeline):
-        history_path = 'pg_{0}/{1:08X}.history'.format(self.wal_name, timeline)
+        history_path = os.path.join(self.wal_dir, '{0:08X}.history'.format(timeline))
-        try:
+        history_mtime = mtime(history_path)
-            cursor = self._connection.cursor()
+        if history_mtime:
-            cursor.execute('SELECT isdir, modification FROM pg_catalog.pg_stat_file(%s)', (history_path,))
+            try:
-            isdir, modification = cursor.fetchone()
+                with open(history_path, 'r') as f:
-            if not isdir:
+                    history = f.read()
-                cursor.execute('SELECT pg_catalog.pg_read_file(%s)', (history_path,))
+                history = list(parse_history(history))
-                history = list(parse_history(cursor.fetchone()[0]))
                 if history[-1][0] == timeline - 1:
-                    history[-1].append(modification.isoformat())
+                    history_mtime = datetime.fromtimestamp(history_mtime).replace(tzinfo=tz.tzlocal())
+                    history[-1].append(history_mtime.isoformat())
                 return history
-        except Exception:
+            except Exception:
-            logger.exception('Failed to read and parse %s', (history_path,))
+                logger.exception('Failed to read and parse %s', (history_path,))
 
     def follow(self, member, role='replica', timeout=None, do_reload=False):
         recovery_params = self.config.build_recovery_params(member)
@@ -731,7 +777,8 @@ class Postgresql(object):
         if self.is_running():
             if do_reload:
                 self.config.write_postgresql_conf()
-                self.reload()
+                if self.reload(block_callbacks=change_role) and change_role:
+                    self.set_role(role)
             else:
                 self.restart(block_callbacks=change_role, role=role)
         else:
@@ -761,21 +808,31 @@ class Postgresql(object):
             ret = self._wait_promote(wait_seconds)
         return ret
 
+    @staticmethod
+    def _wal_position(is_leader, wal_position, received_location, replayed_location):
+        return wal_position if is_leader else max(received_location or 0, replayed_location or 0)
+
     def timeline_wal_position(self):
         # This method could be called from different threads (simultaneously with some other `_query` calls).
         # If it is called not from main thread we will create a new cursor to execute statement.
         if current_thread().ident == self.__thread_ident:
-            return (self._cluster_info_state_get('timeline'),
+            timeline = self._cluster_info_state_get('timeline')
-                    self._cluster_info_state_get('wal_position'),
+            wal_position = self._cluster_info_state_get('wal_position')
-                    self._cluster_info_state_get('pg_control_timeline'))
+            replayed_location = self.replayed_location()
+            received_location = self.received_location()
+            pg_control_timeline = self._cluster_info_state_get('pg_control_timeline')
+        else:
+            with self.connection().cursor() as cursor:
+                cursor.execute(self.cluster_info_query)
+                (timeline, wal_position, replayed_location,
+                 received_location, _, pg_control_timeline) = cursor.fetchone()[:6]
 
-        with self.connection().cursor() as cursor:
+        wal_position = self._wal_position(timeline, wal_position, received_location, replayed_location)
-            cursor.execute(self.cluster_info_query)
+        return (timeline, wal_position, pg_control_timeline)
-            return cursor.fetchone()[:3]
 
     def postmaster_start_time(self):
         try:
-            query = "SELECT pg_catalog.to_char(pg_catalog.pg_postmaster_start_time(), 'YYYY-MM-DD HH24:MI:SS.MS TZ')"
+            query = "SELECT " + self.POSTMASTER_START_TIME
             if current_thread().ident == self.__thread_ident:
                 return self.query(query).fetchone()[0]
             with self.connection().cursor() as cursor:
@@ -785,7 +842,8 @@ class Postgresql(object):
             return None
 
     def last_operation(self):
-        return str(self._cluster_info_state_get('wal_position'))
+        return str(self._wal_position(self.is_leader(), self._cluster_info_state_get('wal_position'),
+                                      self.received_location(), self.replayed_location()))
 
     def configure_server_parameters(self):
         self._major_version = self.get_major_version()
@@ -821,6 +879,15 @@ class Postgresql(object):
                         pg_wal_realpath = os.path.realpath(pg_wal_path)
                         logger.info('Removing WAL directory: %s', pg_wal_realpath)
                         shutil.rmtree(pg_wal_realpath)
+                # Remove user defined tablespace directory
+                pg_tblsp_dir = os.path.join(self._data_dir, 'pg_tblspc')
+                if os.path.exists(pg_tblsp_dir):
+                    for tsdn in os.listdir(pg_tblsp_dir):
+                        pg_tsp_path = os.path.join(pg_tblsp_dir, tsdn)
+                        if parse_int(tsdn) and os.path.islink(pg_tsp_path):
+                            pg_tsp_rpath = os.path.realpath(pg_tsp_path)
+                            logger.info('Removing user defined tablespace directory: %s', pg_tsp_rpath)
+                            shutil.rmtree(pg_tsp_rpath, ignore_errors=True)
 
                 shutil.rmtree(self._data_dir)
         except (IOError, OSError):
@@ -860,53 +927,6 @@ class Postgresql(object):
             return candidates[0], False
         return None, False
 
-    def read_postmaster_opts(self):
-        """returns the list of option names/values from postgres.opts, Empty dict if read failed or no file"""
-        result = {}
-        try:
-            with open(os.path.join(self._data_dir, 'postmaster.opts')) as f:
-                data = f.read()
-                for opt in data.split('" "'):
-                    if '=' in opt and opt.startswith('--'):
-                        name, val = opt.split('=', 1)
-                        result[name.strip('-')] = val.rstrip('"\n')
-        except IOError:
-            logger.exception('Error when reading postmaster.opts')
-        return result
-
-    def single_user_mode(self, command=None, options=None):
-        """run a given command in a single-user mode. If the command is empty - then just start and stop"""
-        cmd = [self.pgcommand('postgres'), '--single', '-D', self._data_dir]
-        for opt, val in sorted((options or {}).items()):
-            cmd.extend(['-c', '{0}={1}'.format(opt, val)])
-        # need a database name to connect
-        cmd.append(self._database)
-        return self.cancellable.call(cmd, communicate_input=command)
-
-    def cleanup_archive_status(self):
-        status_dir = os.path.join(self._data_dir, 'pg_' + self.wal_name, 'archive_status')
-        try:
-            for f in os.listdir(status_dir):
-                path = os.path.join(status_dir, f)
-                try:
-                    if os.path.islink(path):
-                        os.unlink(path)
-                    elif os.path.isfile(path):
-                        os.remove(path)
-                except OSError:
-                    logger.exception('Unable to remove %s', path)
-        except OSError:
-            logger.exception('Unable to list %s', status_dir)
-
-    def fix_cluster_state(self):
-        self.cleanup_archive_status()
-
-        # Start in a single user mode and stop to produce a clean shutdown
-        opts = self.read_postmaster_opts()
-        opts.update({'archive_mode': 'on', 'archive_command': 'false'})
-        self.config.remove_recovery_conf()
-        return self.single_user_mode(options=opts) == 0 or None
-
     def schedule_sanity_checks_after_pause(self):
         """
             After coming out of pause we have to:

patroni/postgresql/bootstrap.py

@@ -130,6 +130,7 @@ class Bootstrap(object):
                 r['host'] = 'localhost'  # set it to localhost to write into pgpass
 
             env = self._postgresql.config.write_pgpass(r) if 'password' in r else None
+            env['PGOPTIONS'] = '-c synchronous_commit=local'
 
             try:
                 ret = self._postgresql.cancellable.call(shlex.split(cmd) + [connstring], env=env)
@@ -362,7 +363,7 @@ END;$$""".format(f, rewind['username'])
                     # at this point there should be no recovery.conf
                     postgresql.config.remove_recovery_conf()
 
-                    if postgresql.config.hba_file and postgresql.config.hba_file != postgresql.config.pg_hba_conf:
+                    if postgresql.config.hba_file:
                         postgresql.restart()
                     else:
                         postgresql.config.replace_pg_hba()

patroni/postgresql/cancellable.py

@@ -1,11 +1,9 @@
 import logging
-import os
 import psutil
 import subprocess
 
 from patroni.exceptions import PostgresException
 from patroni.utils import polling_loop
-from six import string_types
 from threading import Lock
 
 logger = logging.getLogger(__name__)
@@ -75,16 +73,16 @@ class CancellableSubprocess(CancellableExecutor):
         for s in ('stdin', 'stdout', 'stderr'):
             kwargs.pop(s, None)
 
-        communicate_input = 'communicate_input' in kwargs
+        communicate = kwargs.pop('communicate', None)
-        if communicate_input:
+        if isinstance(communicate, dict):
-            input_data = kwargs.pop('communicate_input', None)
+            input_data = communicate.get('input')
-            if not isinstance(input_data, string_types):
+            if input_data:
-                input_data = ''
+                if input_data[-1] != '\n':
-            if input_data and input_data[-1] != '\n':
+                    input_data += '\n'
-                input_data += '\n'
+                input_data = input_data.encode('utf-8')
             kwargs['stdin'] = subprocess.PIPE
-            kwargs['stdout'] = open(os.devnull, 'w')
+            kwargs['stdout'] = subprocess.PIPE
-            kwargs['stderr'] = subprocess.STDOUT
+            kwargs['stderr'] = subprocess.PIPE
 
         try:
             with self._lock:
@@ -95,10 +93,8 @@ class CancellableSubprocess(CancellableExecutor):
                 started = self._start_process(*args, **kwargs)
 
             if started:
-                if communicate_input:
+                if isinstance(communicate, dict):
-                    if input_data:
+                    communicate['stdout'], communicate['stderr'] = self._process.communicate(input_data)
-                        self._process.communicate(input_data)
-                    self._process.stdin.close()
                 return self._process.wait()
         finally:
             with self._lock:

patroni/postgresql/config.py

@@ -113,17 +113,17 @@ def parse_dsn(value):
     Very simple equivalent of `psycopg2.extensions.parse_dsn` introduced in 2.7.0.
     We are not using psycopg2 function in order to remain compatible with 2.5.4+.
     There is one minor difference though, this function removes `dbname` from the result
-    and sets the sslmode` to `prefer` if it is not present in the connection string.
+    and sets the `sslmode`, 'gssencmode', and `channel_binding` to `prefer` if it is not present in
-    This is necessary to simplify comparison of the old and the new values.
+    the connection string. This is necessary to simplify comparison of the old and the new values.
 
     >>> r = parse_dsn('postgresql://u%2Fse:pass@:%2f123,[%2Fhost2]/db%2Fsdf?application_name=mya%2Fpp&ssl=true')
     >>> r == {'application_name': 'mya/pp', 'host': ',/host2', 'sslmode': 'require',\
-              'password': 'pass', 'port': '/123', 'user': 'u/se'}
+              'password': 'pass', 'port': '/123', 'user': 'u/se', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
     >>> r = parse_dsn(" host = 'host' dbname = db\\\\ name requiressl=1 ")
-    >>> r == {'host': 'host', 'sslmode': 'require'}
+    >>> r == {'host': 'host', 'sslmode': 'require', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
-    >>> parse_dsn('requiressl = 0\\\\') == {'sslmode': 'prefer'}
+    >>> parse_dsn('requiressl = 0\\\\') == {'sslmode': 'prefer', 'gssencmode': 'prefer', 'channel_binding': 'prefer'}
     True
     >>> parse_dsn("host=a foo = '") is None
     True
@@ -147,6 +147,8 @@ def parse_dsn(value):
             ret.setdefault('sslmode', 'prefer')
         if 'dbname' in ret:
             del ret['dbname']
+        ret.setdefault('gssencmode', 'prefer')
+        ret.setdefault('channel_binding', 'prefer')
     return ret
 
 
@@ -374,7 +376,7 @@ class ConfigHandler(object):
             configuration.append(os.path.basename(self._postgresql_base_conf_name))
         if not self.hba_file:
             configuration.append('pg_hba.conf')
-        if not self._server_parameters.get('ident_file'):
+        if not self.ident_file:
             configuration.append('pg_ident.conf')
         return configuration
 
@@ -481,7 +483,7 @@ class ConfigHandler(object):
         :returns: True if pg_ident.conf was rewritten.
         """
 
-        if not self._server_parameters.get('ident_file') and self._config.get('pg_ident'):
+        if not self.ident_file and self._config.get('pg_ident'):
             with ConfigWriter(self._pg_ident_conf) as f:
                 f.writelines(self._config['pg_ident'])
             return True
@@ -492,6 +494,10 @@ class ConfigHandler(object):
         ret = member.conn_kwargs(self.replication)
         ret['application_name'] = self._postgresql.name
         ret.setdefault('sslmode', 'prefer')
+        if self._postgresql.major_version >= 120000:
+            ret.setdefault('gssencmode', 'prefer')
+        if self._postgresql.major_version >= 130000:
+            ret.setdefault('channel_binding', 'prefer')
         if self._krbsrvname:
             ret['krbsrvname'] = self._krbsrvname
         if 'database' in ret:
@@ -500,8 +506,9 @@ class ConfigHandler(object):
 
     def format_dsn(self, params, include_dbname=False):
         # A list of keywords that can be found in a conninfo string. Follows what is acceptable by libpq
-        keywords = ('dbname', 'user', 'passfile' if params.get('passfile') else 'password', 'host', 'port', 'sslmode',
+        keywords = ('dbname', 'user', 'passfile' if params.get('passfile') else 'password', 'host', 'port',
-                    'sslcompression', 'sslcert', 'sslkey', 'sslrootcert', 'sslcrl', 'application_name', 'krbsrvname')
+                    'sslmode', 'sslcompression', 'sslcert', 'sslkey', 'sslrootcert', 'sslcrl',
+                    'application_name', 'krbsrvname', 'gssencmode', 'channel_binding')
         if include_dbname:
             params = params.copy()
             params['dbname'] = params.get('database') or self._postgresql.database
@@ -645,6 +652,17 @@ class ConfigHandler(object):
         elif not primary_conninfo:
             return False
 
+        wal_receiver_primary_conninfo = self._postgresql.primary_conninfo()
+        if wal_receiver_primary_conninfo:
+            wal_receiver_primary_conninfo = parse_dsn(wal_receiver_primary_conninfo)
+            # when wal receiver is alive use primary_conninfo from pg_stat_wal_receiver for comparison
+            if wal_receiver_primary_conninfo:
+                primary_conninfo = wal_receiver_primary_conninfo
+                # There could be no password in the primary_conninfo or it is masked.
+                # Just copy the "desired" value in order to make comparison succeed.
+                if 'password' in wanted_primary_conninfo:
+                    primary_conninfo['password'] = wanted_primary_conninfo['password']
+
         if 'passfile' in primary_conninfo and 'password' not in primary_conninfo \
                 and 'password' in wanted_primary_conninfo:
             if self._check_passfile(primary_conninfo['passfile'], wanted_primary_conninfo):
@@ -688,6 +706,13 @@ class ConfigHandler(object):
             else:  # empty string, primary_conninfo is not in the config
                 primary_conninfo[0] = {}
 
+        # when wal receiver is alive take primary_slot_name from pg_stat_wal_receiver
+        wal_receiver_primary_slot_name = self._postgresql.primary_slot_name()
+        if not wal_receiver_primary_slot_name and self._postgresql.primary_conninfo():
+            wal_receiver_primary_slot_name = ''
+        if wal_receiver_primary_slot_name is not None:
+            self._current_recovery_params['primary_slot_name'][0] = wal_receiver_primary_slot_name
+
         required = {'restart': 0, 'reload': 0}
 
         def record_missmatch(mtype):
@@ -938,10 +963,12 @@ class ConfigHandler(object):
                         logger.warning('Removing invalid parameter `%s` from postgresql.parameters', param)
                         server_parameters.pop(param)
 
-            if not server_parameters.get('hba_file') and config.get('pg_hba'):
+            if (not server_parameters.get('hba_file') or server_parameters['hba_file'] == self._pg_hba_conf) \
+                    and config.get('pg_hba'):
                 hba_changed = self._config.get('pg_hba', []) != config['pg_hba']
 
-            if not server_parameters.get('ident_file') and config.get('pg_ident'):
+            if (not server_parameters.get('ident_file') or server_parameters['ident_file'] == self._pg_hba_conf) \
+                    and config.get('pg_ident'):
                 ident_changed = self._config.get('pg_ident', []) != config['pg_ident']
 
         self._config = config
@@ -1025,6 +1052,10 @@ class ConfigHandler(object):
 
         for name, cname in options_mapping.items():
             value = parse_int(effective_configuration[name])
+            if cname not in data:
+                logger.warning('%s is missing from pg_controldata output', cname)
+                continue
+
             cvalue = parse_int(data[cname])
             if cvalue > value:
                 effective_configuration[name] = cvalue
@@ -1044,9 +1075,15 @@ class ConfigHandler(object):
         return self._config['authentication'].get('rewind', self._superuser) \
                 if self._postgresql.major_version >= 110000 else self._superuser
 
+    @property
+    def ident_file(self):
+        ident_file = self._server_parameters.get('ident_file')
+        return None if ident_file == self._pg_ident_conf else ident_file
+
     @property
     def hba_file(self):
-        return self._server_parameters.get('hba_file')
+        hba_file = self._server_parameters.get('hba_file')
+        return None if hba_file == self._pg_hba_conf else hba_file
 
     @property
     def pg_hba_conf(self):

patroni/postgresql/rewind.py

@@ -1,10 +1,14 @@
 import logging
 import os
+import six
 import subprocess
 
-from patroni.dcs import Leader
+from threading import Lock, Thread
-from patroni.postgresql.connection import get_connection_cursor
+
-from patroni.postgresql.misc import parse_history, parse_lsn
+from .connection import get_connection_cursor
+from .misc import parse_history, parse_lsn
+from ..async_executor import CriticalTask
+from ..dcs import Leader
 
 logger = logging.getLogger(__name__)
 
@@ -12,10 +16,16 @@ REWIND_STATUS = type('Enum', (), {'INITIAL': 0, 'CHECKPOINT': 1, 'CHECK': 2, 'NE
                                   'NOT_NEED': 4, 'SUCCESS': 5, 'FAILED': 6})
 
 
+def format_lsn(lsn, full=False):
+    template = '{0:X}/{1:08X}' if full else '{0:X}/{1:X}'
+    return template.format(lsn >> 32, lsn & 0xFFFFFFFF)
+
+
 class Rewind(object):
 
     def __init__(self, postgresql):
         self._postgresql = postgresql
+        self._checkpoint_task_lock = Lock()
         self.reset_state()
 
     @staticmethod
@@ -60,32 +70,102 @@ class Rewind(object):
         except Exception:
             return logger.exception('Exception when working with leader')
 
+    def _get_checkpoint_end(self, timeline, lsn):
+        """The checkpoint record size in WAL depends on postgres major version and platform (memory alignment).
+        Hence, the only reliable way to figure out where it ends, read the record from file with the help of pg_waldump
+        and parse the output. We are trying to read two records, and expect that it wil fail to read the second one:
+        `pg_waldump: fatal: error in WAL record at 0/182E220: invalid record length at 0/182E298: wanted 24, got 0`
+        The error message contains information about LSN of the next record, which is exactly where checkpoint ends."""
+
+        cmd = self._postgresql.pgcommand('pg_{0}dump'.format(self._postgresql.wal_name))
+        lsn8 = format_lsn(lsn, True)
+        lsn = format_lsn(lsn)
+        env = os.environ.copy()
+        env.update(LANG='C', LC_ALL='C', PGDATA=self._postgresql.data_dir)
+        try:
+            waldump = subprocess.Popen([cmd, '-t', str(timeline), '-s', lsn, '-n', '2'],
+                                       stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env)
+            out, err = waldump.communicate()
+            waldump.wait()
+        except Exception as e:
+            logger.error('Failed to execute `%s -t %s -s %s -n 2`: %r', cmd, timeline, lsn, e)
+        else:
+            out = out.decode('utf-8').rstrip().split('\n')
+            err = err.decode('utf-8').rstrip().split('\n')
+            pattern = 'error in WAL record at {0}: invalid record length at '.format(lsn)
+
+            if len(out) == 1 and len(err) == 1 and ', lsn: {0}, prev '.format(lsn8) in out[0] and pattern in err[0]:
+                i = err[0].find(pattern) + len(pattern)
+                j = err[0].find(": wanted ", i)
+                if j > -1:
+                    try:
+                        return parse_lsn(err[0][i:j])
+                    except Exception as e:
+                        logger.error('Failed to parse lsn %s: %r', err[0][i:j], e)
+            logger.error('Failed to parse `%s -t %s -s %s -n 2` output', cmd, timeline, lsn)
+            logger.error(' stdout=%s', '\n'.join(out))
+            logger.error(' stderr=%s', '\n'.join(err))
+
+        return 0
+
     def _get_local_timeline_lsn_from_controldata(self):
-        timeline = lsn = None
+        in_recovery = timeline = lsn = None
         data = self._postgresql.controldata()
         try:
             if data.get('Database cluster state') == 'shut down in recovery':
+                in_recovery = True
                 lsn = data.get('Minimum recovery ending location')
                 timeline = int(data.get("Min recovery ending loc's timeline"))
                 if lsn == '0/0' or timeline == 0:  # it was a master when it crashed
                     data['Database cluster state'] = 'shut down'
             if data.get('Database cluster state') == 'shut down':
+                in_recovery = False
                 lsn = data.get('Latest checkpoint location')
                 timeline = int(data.get("Latest checkpoint's TimeLineID"))
         except (TypeError, ValueError):
             logger.exception('Failed to get local timeline and lsn from pg_controldata output')
-        return timeline, lsn
+
+        if lsn is not None:
+            try:
+                lsn = parse_lsn(lsn)
+            except (IndexError, ValueError) as e:
+                logger.error('Exception when parsing lsn %s: %r', lsn, e)
+                lsn = None
+
+        return in_recovery, timeline, lsn
 
     def _get_local_timeline_lsn(self):
-        if self._postgresql.is_running():  # if postgres is running - get timeline and lsn from replication connection
+        if self._postgresql.is_running():  # if postgres is running - get timeline from replication connection
-            timeline, lsn = self._postgresql.get_local_timeline_lsn_from_replication_connection()
+            in_recovery = True
+            timeline = self._postgresql.received_timeline() or self._postgresql.get_replica_timeline()
+            lsn = self._postgresql.replayed_location()
         else:  # otherwise analyze pg_controldata output
-            timeline, lsn = self._get_local_timeline_lsn_from_controldata()
+            in_recovery, timeline, lsn = self._get_local_timeline_lsn_from_controldata()
-        logger.info('Local timeline=%s lsn=%s', timeline, lsn)
+
-        return timeline, lsn
+        log_lsn = format_lsn(lsn) if isinstance(lsn, six.integer_types) else lsn
+        logger.info('Local timeline=%s lsn=%s', timeline, log_lsn)
+        return in_recovery, timeline, lsn
+
+    @staticmethod
+    def _log_master_history(history, i):
+        start = max(0, i - 3)
+        end = None if i + 4 >= len(history) else i + 2
+        history_show = []
+
+        def format_history_line(line):
+            return '{0}\t{1}\t{2}'.format(line[0], format_lsn(line[1]), line[2])
+
+        for line in history[start:end]:
+            history_show.append(format_history_line(line))
+
+        if line != history[-1]:
+            history_show.append('...')
+            history_show.append(format_history_line(history[-1]))
+
+        logger.info('master: history=%s', '\n'.join(history_show))
 
     def _check_timeline_and_lsn(self, leader):
-        local_timeline, local_lsn = self._get_local_timeline_lsn()
+        in_recovery, local_timeline, local_lsn = self._get_local_timeline_lsn()
         if local_timeline is None or local_lsn is None:
             return
 
@@ -104,25 +184,32 @@ class Rewind(object):
                 logger.info('master_timeline=%s', master_timeline)
                 if local_timeline > master_timeline:  # Not always supported by pg_rewind
                     need_rewind = True
+                elif local_timeline == master_timeline:
+                    need_rewind = False
                 elif master_timeline > 1:
                     cur.execute('TIMELINE_HISTORY %s', (master_timeline,))
                     history = bytes(cur.fetchone()[1]).decode('utf-8')
-                    logger.info('master: history=%s', history)
+                    logger.debug('master: history=%s', history)
-                else:  # local_timeline == master_timeline == 1
-                    need_rewind = False
         except Exception:
             return logger.exception('Exception when working with master via replication connection')
 
         if history is not None:
-            for parent_timeline, switchpoint, _ in parse_history(history):
+            history = list(parse_history(history))
+            for i, (parent_timeline, switchpoint, _) in enumerate(history):
                 if parent_timeline == local_timeline:
-                    try:
+                    # We don't need to rewind when:
-                        need_rewind = parse_lsn(local_lsn) >= switchpoint
+                    # 1. for replica: replayed location is not ahead of switchpoint
-                    except (IndexError, ValueError):
+                    # 2. for the former primary: end of checkpoint record is the same as switchpoint
-                        logger.exception('Exception when parsing lsn')
+                    if in_recovery:
+                        need_rewind = local_lsn > switchpoint
+                    elif local_lsn >= switchpoint:
+                        need_rewind = True
+                    else:
+                        need_rewind = switchpoint != self._get_checkpoint_end(local_timeline, local_lsn)
                     break
                 elif parent_timeline > local_timeline:
                     break
+            self._log_master_history(history, i)
 
         self._state = need_rewind and REWIND_STATUS.NEED or REWIND_STATUS.NOT_NEED
 
@@ -131,25 +218,114 @@ class Rewind(object):
             self._check_timeline_and_lsn(leader)
         return leader and leader.conn_url and self._state == REWIND_STATUS.NEED
 
-    def check_for_checkpoint_after_promote(self):
+    def __checkpoint(self, task, wakeup):
-        if self._state == REWIND_STATUS.INITIAL and self._postgresql.is_leader() and \
+        try:
-                self._postgresql.get_master_timeline() == self._postgresql.pg_control_timeline():
+            result = self._postgresql.checkpoint()
-            self._state = REWIND_STATUS.CHECKPOINT
+        except Exception as e:
+            result = 'Exception: ' + str(e)
+        with task:
+            task.complete(not bool(result))
+            if task.result:
+                wakeup()
+
+    def ensure_checkpoint_after_promote(self, wakeup):
+        """After promote issue a CHECKPOINT from a new thread and asynchronously check the result.
+        In case if CHECKPOINT failed, just check that timeline in pg_control was updated."""
+
+        if self._state == REWIND_STATUS.INITIAL and self._postgresql.is_leader():
+            with self._checkpoint_task_lock:
+                if self._checkpoint_task:
+                    with self._checkpoint_task:
+                        if self._checkpoint_task.result:
+                            self._state = REWIND_STATUS.CHECKPOINT
+                        if self._checkpoint_task.result is not False:
+                            return
+                else:
+                    self._checkpoint_task = CriticalTask()
+                    return Thread(target=self.__checkpoint, args=(self._checkpoint_task, wakeup)).start()
+
+            if self._postgresql.get_master_timeline() == self._postgresql.pg_control_timeline():
+                self._state = REWIND_STATUS.CHECKPOINT
 
     def checkpoint_after_promote(self):
         return self._state == REWIND_STATUS.CHECKPOINT
 
+    def _fetch_missing_wal(self, restore_command, wal_filename):
+        cmd = ''
+        length = len(restore_command)
+        i = 0
+        while i < length:
+            if restore_command[i] == '%' and i + 1 < length:
+                i += 1
+                if restore_command[i] == 'p':
+                    cmd += os.path.join(self._postgresql.wal_dir, wal_filename)
+                elif restore_command[i] == 'f':
+                    cmd += wal_filename
+                elif restore_command[i] == 'r':
+                    cmd += '000000010000000000000001'
+                elif restore_command[i] == '%':
+                    cmd += '%'
+                else:
+                    cmd += '%'
+                    i -= 1
+            else:
+                cmd += restore_command[i]
+            i += 1
+
+        logger.info('Trying to fetch the missing wal: %s', cmd)
+        return self._postgresql.cancellable.call(cmd, shell=True) == 0
+
+    def _find_missing_wal(self, data):
+        # could not open file "$PGDATA/pg_wal/0000000A00006AA100000068": No such file or directory
+        pattern = 'could not open file "'
+        for line in data.decode('utf-8').split('\n'):
+            b = line.find(pattern)
+            if b > -1:
+                b += len(pattern)
+                e = line.find('": ', b)
+                if e > -1:
+                    waldir, wal_filename = os.path.split(line[b:e])
+                    if waldir.endswith(os.path.sep + 'pg_' + self._postgresql.wal_name) and len(wal_filename) == 24:
+                        return wal_filename
+
     def pg_rewind(self, r):
         # prepare pg_rewind connection
         env = self._postgresql.config.write_pgpass(r)
-        env['PGOPTIONS'] = '-c statement_timeout=0'
+        env.update(LANG='C', LC_ALL='C', PGOPTIONS='-c statement_timeout=0')
         dsn = self._postgresql.config.format_dsn(r, True)
         logger.info('running pg_rewind from %s', dsn)
-        try:
+
-            return self._postgresql.cancellable.call([self._postgresql.pgcommand('pg_rewind'), '-D',
+        restore_command = self._postgresql.config.get('recovery_conf', {}).get('restore_command') \
-                                                      self._postgresql.data_dir, '--source-server', dsn], env=env) == 0
+            if self._postgresql.major_version < 120000 else self._postgresql.get_guc_value('restore_command')
-        except OSError:
+
-            return False
+        cmd = [self._postgresql.pgcommand('pg_rewind')]
+        if self._postgresql.major_version >= 130000 and restore_command:
+            cmd.append('--restore-target-wal')
+        cmd.extend(['-D', self._postgresql.data_dir, '--source-server', dsn])
+
+        while True:
+            results = {}
+            ret = self._postgresql.cancellable.call(cmd, env=env, communicate=results)
+
+            logger.info('pg_rewind exit code=%s', ret)
+            if ret is None:
+                return False
+
+            logger.info(' stdout=%s', results['stdout'].decode('utf-8'))
+            logger.info(' stderr=%s', results['stderr'].decode('utf-8'))
+            if ret == 0:
+                return True
+
+            if not restore_command or self._postgresql.major_version >= 130000:
+                return False
+
+            missing_wal = self._find_missing_wal(results['stderr']) or self._find_missing_wal(results['stdout'])
+            if not missing_wal:
+                return False
+
+            if not self._fetch_missing_wal(restore_command, missing_wal):
+                logger.info('Failed to fetch WAL segment %s required for pg_rewind', missing_wal)
+                return False
 
     def execute(self, leader):
         if self._postgresql.is_running() and not self._postgresql.stop(checkpoint=False):
@@ -191,6 +367,8 @@ class Rewind(object):
 
     def reset_state(self):
         self._state = REWIND_STATUS.INITIAL
+        with self._checkpoint_task_lock:
+            self._checkpoint_task = None
 
     @property
     def is_needed(self):
@@ -203,3 +381,50 @@ class Rewind(object):
     @property
     def failed(self):
         return self._state == REWIND_STATUS.FAILED
+
+    def read_postmaster_opts(self):
+        """returns the list of option names/values from postgres.opts, Empty dict if read failed or no file"""
+        result = {}
+        try:
+            with open(os.path.join(self._postgresql.data_dir, 'postmaster.opts')) as f:
+                data = f.read()
+                for opt in data.split('" "'):
+                    if '=' in opt and opt.startswith('--'):
+                        name, val = opt.split('=', 1)
+                        result[name.strip('-')] = val.rstrip('"\n')
+        except IOError:
+            logger.exception('Error when reading postmaster.opts')
+        return result
+
+    def single_user_mode(self, communicate=None, options=None):
+        """run a given command in a single-user mode. If the command is empty - then just start and stop"""
+        cmd = [self._postgresql.pgcommand('postgres'), '--single', '-D', self._postgresql.data_dir]
+        for opt, val in sorted((options or {}).items()):
+            cmd.extend(['-c', '{0}={1}'.format(opt, val)])
+        # need a database name to connect
+        cmd.append('template1')
+        return self._postgresql.cancellable.call(cmd, communicate=communicate)
+
+    def cleanup_archive_status(self):
+        status_dir = os.path.join(self._postgresql.wal_dir, 'archive_status')
+        try:
+            for f in os.listdir(status_dir):
+                path = os.path.join(status_dir, f)
+                try:
+                    if os.path.islink(path):
+                        os.unlink(path)
+                    elif os.path.isfile(path):
+                        os.remove(path)
+                except OSError:
+                    logger.exception('Unable to remove %s', path)
+        except OSError:
+            logger.exception('Unable to list %s', status_dir)
+
+    def ensure_clean_shutdown(self):
+        self.cleanup_archive_status()
+
+        # Start in a single user mode and stop to produce a clean shutdown
+        opts = self.read_postmaster_opts()
+        opts.update({'archive_mode': 'on', 'archive_command': 'false'})
+        self._postgresql.config.remove_recovery_conf()
+        return self.single_user_mode(options=opts) == 0 or None

patroni/utils.py

@@ -357,6 +357,8 @@ def polling_loop(timeout, interval=1):
 
 def split_host_port(value, default_port):
     t = value.rsplit(':', 1)
+    if ':' in t[0]:
+        t[0] = t[0].strip('[]')
     t.append(default_port)
     return t[0], int(t[1])
 

patroni/version.py

@@ -1 +1 @@
-__version__ = '1.6.4'
+__version__ = '1.6.5'

setup.py

@@ -55,6 +55,55 @@ CONSOLE_SCRIPTS = ['patroni = patroni:main',
                    "patroni_aws = patroni.scripts.aws:main"]
 
 
+class Flake8(Command):
+
+    user_options = []
+
+    def initialize_options(self):
+        from flake8.main import application
+
+        self.flake8 = application.Application()
+        self.flake8.initialize([])
+
+    def finalize_options(self):
+        pass
+
+    def package_files(self):
+        seen_package_directories = ()
+        directories = self.distribution.package_dir or {}
+        empty_directory_exists = "" in directories
+        packages = self.distribution.packages or []
+        for package in packages:
+            if package in directories:
+                package_directory = directories[package]
+            elif empty_directory_exists:
+                package_directory = os.path.join(directories[""], package)
+            else:
+                package_directory = package
+
+            if not package_directory.startswith(seen_package_directories):
+                seen_package_directories += (package_directory + ".",)
+                yield package_directory
+
+    def targets(self):
+        return [package for package in self.package_files()] + ['tests', 'setup.py']
+
+    def run(self):
+        self.flake8.run_checks(self.targets())
+        self.flake8.formatter.start()
+        self.flake8.report_errors()
+        self.flake8.report_statistics()
+        self.flake8.report_benchmarks()
+        self.flake8.formatter.stop()
+        try:
+            self.flake8.exit()
+        except SystemExit as e:
+            # Cause system exit only if exit code is not zero (terminates
+            # other possibly remaining/pending setuptools commands).
+            if e.code:
+                raise
+
+
 class PyTest(Command):
 
     user_options = [('cov=', None, 'Run coverage'), ('cov-xml=', None, 'Generate junit xml report'),
@@ -106,7 +155,7 @@ def read(fname):
 
 def setup_package(version):
     # Assemble additional setup commands
-    cmdclass = {'test': PyTest}
+    cmdclass = {'test': PyTest, 'flake8': Flake8}
 
     install_requires = []
 

tests/__init__.py

@@ -1,4 +1,3 @@
-import datetime
 import os
 import shutil
 import unittest
@@ -88,7 +87,7 @@ class MockCursor(object):
         elif sql.startswith('SELECT slot_name'):
             self.results = [('blabla', 'physical'), ('foobar', 'physical'), ('ls', 'logical', 'a', 'b')]
         elif sql.startswith('SELECT CASE WHEN pg_catalog.pg_is_in_recovery()'):
-            self.results = [(1, 2, 1)]
+            self.results = [(1, 2, 1, 0, False, 1, 1, None, None)]
         elif sql.startswith('SELECT pg_catalog.pg_is_in_recovery()'):
             self.results = [(False, 2)]
         elif sql.startswith('SELECT pg_catalog.to_char'):
@@ -106,12 +105,7 @@ class MockCursor(object):
                             ('autovacuum', 'on', None, 'bool', 'sighup'),
                             ('unix_socket_directories', '/tmp', None, 'string', 'postmaster')]
         elif sql.startswith('IDENTIFY_SYSTEM'):
-            self.results = [('1', 2, '0/402EEC0', '')]
+            self.results = [('1', 3, '0/402EEC0', '')]
-        elif sql.startswith('SELECT isdir, modification'):
-            self.results = [(False, datetime.datetime.now())]
-        elif sql.startswith('SELECT pg_catalog.pg_read_file'):
-            self.results = [('1\t0/40159C0\tno recovery target specified\n\n'
-                             '2\t1/40159C0\tno recovery target specified\n',)]
         elif sql.startswith('TIMELINE_HISTORY '):
             self.results = [('', b'x\t0/40159C0\tno recovery target specified\n\n'
                                  b'1\t0/40159C0\tno recovery target specified\n\n'

tests/test_api.py

@@ -30,6 +30,8 @@ class MockPostgresql(object):
     pending_restart = True
     wal_name = 'wal'
     lsn_name = 'lsn'
+    POSTMASTER_START_TIME = 'pg_catalog.to_char(pg_catalog.pg_postmaster_start_time'
+    TL_LSN = 'CASE WHEN pg_catalog.pg_is_in_recovery()'
 
     @staticmethod
     def connection():
@@ -177,6 +179,8 @@ class TestRestApiHandler(unittest.TestCase):
             MockRestApiServer(RestApiHandler, 'GET /asynchronous')
         MockPatroni.ha.is_leader = Mock(return_value=True)
         MockRestApiServer(RestApiHandler, 'GET /replica')
+        with patch.object(MockHa, 'is_standby_cluster', Mock(return_value=True)):
+            MockRestApiServer(RestApiHandler, 'GET /standby_leader')
         MockPatroni.dcs.cluster = None
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'master'})):
             MockRestApiServer(RestApiHandler, 'GET /master')
@@ -201,8 +205,8 @@ class TestRestApiHandler(unittest.TestCase):
 
     @patch.object(MockPatroni, 'dcs')
     def test_do_GET_cluster(self, mock_dcs):
-        mock_dcs.cluster = get_cluster_initialized_without_leader()
+        mock_dcs.get_cluster.return_value = get_cluster_initialized_without_leader()
-        mock_dcs.cluster.members[1].data['xlog_location'] = 11
+        mock_dcs.get_cluster.return_value.members[1].data['xlog_location'] = 11
         self.assertIsNotNone(MockRestApiServer(RestApiHandler, 'GET /cluster'))
 
     @patch.object(MockPatroni, 'dcs')
@@ -307,6 +311,15 @@ class TestRestApiHandler(unittest.TestCase):
                 request = 'DELETE /restart HTTP/1.0' + self._authorization
                 self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
 
+    @patch.object(MockPatroni, 'dcs')
+    def test_do_DELETE_switchover(self, mock_dcs):
+        request = 'DELETE /switchover HTTP/1.0' + self._authorization
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+        mock_dcs.manual_failover.return_value = False
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+        mock_dcs.get_cluster.return_value.failover = None
+        self.assertIsNotNone(MockRestApiServer(RestApiHandler, request))
+
     @patch.object(MockPatroni, 'dcs')
     def test_do_POST_reinitialize(self, mock_dcs):
         cluster = mock_dcs.get_cluster.return_value
@@ -413,25 +426,27 @@ class TestRestApiHandler(unittest.TestCase):
         MockRestApiServer(RestApiHandler, post + '37\n\n{"candidate":"2","scheduled_at": "1"}')
 
 
-@patch('ssl.SSLContext.load_cert_chain', Mock())
-@patch('ssl.SSLContext.wrap_socket', Mock(return_value=0))
-@patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
 class TestRestApiServer(unittest.TestCase):
 
+    @patch('ssl.SSLContext.load_cert_chain', Mock())
+    @patch('ssl.SSLContext.wrap_socket', Mock(return_value=0))
+    @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
+    def setUp(self):
+        self.srv = MockRestApiServer(Mock(), '', {'listen': '*:8008', 'certfile': 'a', 'verify_client': 'required'})
+
+    @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock())
     def test_reload_config(self):
         bad_config = {'listen': 'foo'}
         self.assertRaises(ValueError, MockRestApiServer, None, '', bad_config)
-        srv = MockRestApiServer(Mock(), '', {'listen': '*:8008', 'certfile': 'a', 'verify_client': 'required'})
+        self.assertRaises(ValueError, self.srv.reload_config, bad_config)
-        self.assertRaises(ValueError, srv.reload_config, bad_config)
+        self.assertRaises(ValueError, self.srv.reload_config, {})
-        self.assertRaises(ValueError, srv.reload_config, {})
         with patch.object(socket.socket, 'setsockopt', Mock(side_effect=socket.error)):
-            srv.reload_config({'listen': ':8008'})
+            self.srv.reload_config({'listen': ':8008'})
 
     def test_check_auth(self):
-        srv = MockRestApiServer(Mock(), '', {'listen': '*:8008', 'certfile': 'a', 'verify_client': 'required'})
         mock_rh = Mock()
         mock_rh.request.getpeercert.return_value = None
-        self.assertIsNot(srv.check_auth(mock_rh), True)
+        self.assertIsNot(self.srv.check_auth(mock_rh), True)
 
     def test_handle_error(self):
         try:
@@ -439,6 +454,18 @@ class TestRestApiServer(unittest.TestCase):
         except Exception:
             self.assertIsNone(MockRestApiServer.handle_error(None, ('127.0.0.1', 55555)))
 
+    @patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock(side_effect=socket.error))
     def test_socket_error(self):
-        with patch.object(BaseHTTPServer.HTTPServer, '__init__', Mock(side_effect=socket.error)):
+        self.assertRaises(socket.error, MockRestApiServer, Mock(), '', {'listen': '*:8008'})
-            self.assertRaises(socket.error, MockRestApiServer, Mock(), '', {'listen': '*:8008'})
+
+    @patch.object(MockRestApiServer, 'finish_request', Mock())
+    def test_process_request_thread(self):
+        mock_socket = Mock()
+        self.srv.process_request_thread((mock_socket, 1), '2')
+        mock_socket.context.wrap_socket.side_effect = socket.error
+        self.srv.process_request_thread((mock_socket, 1), '2')
+
+    @patch.object(socket.socket, 'accept', Mock(return_value=(1, '2')))
+    def test_get_request(self):
+        self.srv.socket = Mock()
+        self.assertEqual(self.srv.get_request(), ((self.srv.socket, 1), '2'))

tests/test_cancellable.py

@@ -13,7 +13,7 @@ class TestCancellableSubprocess(unittest.TestCase):
 
     def test_call(self):
         self.c.cancel()
-        self.assertRaises(PostgresException, self.c.call, communicate_input=None)
+        self.assertRaises(PostgresException, self.c.call)
 
     def test__kill_children(self):
         self.c._process_children = [Mock()]

tests/test_consul.py

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

tests/test_ctl.py

@@ -19,9 +19,7 @@ from .test_ha import get_cluster_initialized_without_leader, get_cluster_initial
     get_cluster_initialized_with_only_leader, get_cluster_not_initialized_without_leader, get_cluster, Member
 
 
-
 def test_rw_config():
-    global CONFIG_FILE_PATH
     runner = CliRunner()
     with runner.isolated_filesystem():
         load_config(CONFIG_FILE_PATH, None)
@@ -32,10 +30,9 @@ def test_rw_config():
         os.rmdir(CONFIG_PATH)
 
 
-@patch('patroni.ctl.load_config',
+@patch('patroni.ctl.load_config', Mock(return_value={
-       Mock(return_value={'scope': 'alpha', 'postgresql': {'data_dir': '.', 'pgpass': './pgpass',
+    'scope': 'alpha', 'restapi': {'listen': '::', 'certfile': 'a'}, 'etcd': {'host': 'localhost:2379'},
-                                                           'parameters': {}, 'retry_timeout': 5},
+    'postgresql': {'data_dir': '.', 'pgpass': './pgpass', 'parameters': {}, 'retry_timeout': 5}}))
-                          'restapi': {'listen': '::', 'certfile': 'a'}, 'etcd': {'host': 'localhost:2379'}}))
 class TestCtl(unittest.TestCase):
 
     @patch('socket.getaddrinfo', socket_getaddrinfo)
@@ -76,7 +73,7 @@ class TestCtl(unittest.TestCase):
         scheduled_at = datetime.now(tzutc) + timedelta(seconds=600)
         cluster = get_cluster_initialized_with_leader(Failover(1, 'foo', 'bar', scheduled_at))
         del cluster.members[1].data['conn_url']
-        for fmt in ('pretty', 'json', 'yaml', 'tsv'):
+        for fmt in ('pretty', 'json', 'yaml', 'tsv', 'topology'):
             self.assertIsNone(output_members(cluster, name='abc', fmt=fmt))
 
     @patch('patroni.ctl.get_dcs')
@@ -426,9 +423,39 @@ class TestCtl(unittest.TestCase):
         assert '2100' in result.output
         assert 'Scheduled restart' in result.output
 
+    @patch('patroni.ctl.get_dcs')
+    def test_topology(self, mock_get_dcs):
+        mock_get_dcs.return_value = self.e
+        cluster = get_cluster_initialized_with_leader()
+        cascade_member = Member(0, 'cascade', 28, {'conn_url': 'postgres://replicator:[email protected]:5437/postgres',
+                                                   'api_url': 'http://127.0.0.1:8012/patroni',
+                                                   'state': 'running',
+                                                   'tags': {'replicatefrom': 'other'},
+                                                   })
+        cascade_member_wrong_tags = Member(0, 'wrong_cascade', 28,
+                                           {'conn_url': 'postgres://replicator:[email protected]:5438/postgres',
+                                            'api_url': 'http://127.0.0.1:8013/patroni',
+                                            'state': 'running',
+                                            'tags': {'replicatefrom': 'nonexistinghost'},
+                                            })
+        cluster.members.append(cascade_member)
+        cluster.members.append(cascade_member_wrong_tags)
+        mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
+        result = self.runner.invoke(ctl, ['topology', 'dummy'])
+        assert '+\n| leader          | 127.0.0.1:5435 |  Leader |' in result.output
+        assert '|\n| + other         | 127.0.0.1:5436 | Replica |' in result.output
+        assert '|\n|   + cascade     | 127.0.0.1:5437 | Replica |' in result.output
+        assert '|\n| + wrong_cascade | 127.0.0.1:5438 | Replica |' in result.output
+
+        cluster = get_cluster_initialized_without_leader()
+        mock_get_dcs.return_value.get_cluster = Mock(return_value=cluster)
+        result = self.runner.invoke(ctl, ['topology', 'dummy'])
+        assert '+\n| + leader | 127.0.0.1:5435 | Replica |' in result.output
+        assert '|\n| + other  | 127.0.0.1:5436 | Replica |' in result.output
+
     @patch('patroni.ctl.get_dcs')
     @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
-    def test_flush(self, mock_get_dcs):
+    def test_flush_restart(self, mock_get_dcs):
         mock_get_dcs.return_value = self.e
         mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
 
@@ -441,6 +468,26 @@ class TestCtl(unittest.TestCase):
             result = self.runner.invoke(ctl, ['flush', 'dummy', 'restart', '--force'])
             assert 'Failed: flush scheduled restart' in result.output
 
+    @patch('patroni.ctl.get_dcs')
+    @patch.object(PoolManager, 'request', Mock(return_value=MockResponse()))
+    def test_flush_switchover(self, mock_get_dcs):
+        mock_get_dcs.return_value = self.e
+
+        mock_get_dcs.return_value.get_cluster = get_cluster_initialized_with_leader
+        result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+        assert 'No pending scheduled switchover' in result.output
+
+        scheduled_at = datetime.now(tzutc) + timedelta(seconds=600)
+        mock_get_dcs.return_value.get_cluster = Mock(
+                return_value=get_cluster_initialized_with_leader(Failover(1, 'a', 'b', scheduled_at)))
+        result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+        assert result.output.startswith('Success: ')
+
+        mock_get_dcs.return_value.manual_failover = Mock()
+        with patch.object(PoolManager, 'request', side_effect=[MockResponse(409), Exception]):
+            result = self.runner.invoke(ctl, ['flush', 'dummy', 'switchover'])
+            assert 'Could not find any accessible member of cluster' in result.output
+
     @patch.object(PoolManager, 'request')
     @patch('patroni.ctl.get_dcs')
     @patch('patroni.ctl.polling_loop', Mock(return_value=[1]))

tests/test_etcd.py

@@ -130,12 +130,11 @@ class TestClient(unittest.TestCase):
             self.client.http.request_encode_body = http_request
 
     def test_machines(self):
-        self.client._base_uri = 'http://localhost:4001'
+        self.client._base_uri = 'http://localhost:4002'
-        self.client._machines_cache = ['http://localhost:2379']
+        self.client._machines_cache = ['http://localhost:4002', 'http://localhost:2379']
         self.assertIsNotNone(self.client.machines)
         self.client._base_uri = 'http://localhost:4001'
-        self.client._machines_cache = []
+        self.client._machines_cache = ['http://localhost:4001']
-        self.assertIsNotNone(self.client.machines)
         self.client._update_machines_cache = True
         machines = None
         try:
@@ -146,16 +145,13 @@ class TestClient(unittest.TestCase):
 
     @patch.object(Client, 'machines')
     def test_api_execute(self, mock_machines):
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
+        mock_machines.__get__ = Mock(return_value=['http://localhost:4001', 'http://localhost:2379'])
         self.assertRaises(ValueError, self.client.api_execute, '', '')
         self.client._base_uri = 'http://localhost:4001'
-        self.client._machines_cache = ['http://localhost:2379']
         self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', 'POST', timeout=0)
         self.client._base_uri = 'http://localhost:4001'
-        self.client._machines_cache = ['http://localhost:2379']
         rtry = Retry(deadline=10, max_delay=1, max_tries=-1, retry_exceptions=(etcd.EtcdLeaderElectionInProgress,))
         rtry(self.client.api_execute, '/', 'POST', timeout=0, params={'retry': rtry})
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
         self.client._machines_cache_updated = 0
         self.client.api_execute('/', 'POST', timeout=0)
         self.client._machines_cache = [self.client._base_uri]
@@ -163,10 +159,17 @@ class TestClient(unittest.TestCase):
         self.assertRaises(etcd.EtcdWatchTimedOut, self.client.api_execute, '/timeout', 'POST', params={'wait': 'true'})
         self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', '')
 
-        with patch.object(Client, '_do_http_request', Mock(side_effect=etcd.EtcdConnectionFailed)):
+        with patch.object(Client, '_calculate_timeouts', Mock(side_effect=[(1, 1, 0), (1, 1, 0), (0, 1, 0)])),\
-            with patch.object(Client, '_calculate_timeouts', Mock(side_effect=[(1, 1, 0), (1, 1, 0), (0, 1, 0)])):
+                patch.object(Client, '_load_machines_cache', Mock(side_effect=Exception)):
-                self.assertRaises(etcd.EtcdException, rtry, self.client.api_execute, '/', 'GET', params={'retry': rtry})
+            self.client.http.request = Mock(side_effect=socket.error)
-            self.client._read_timeout = 0
+            self.assertRaises(etcd.EtcdException, rtry, self.client.api_execute, '/', 'GET', params={'retry': rtry})
+
+        with patch.object(Client, '_calculate_timeouts', Mock(side_effect=[(1, 1, 0), (1, 1, 0), (0, 1, 0)])),\
+                patch.object(Client, '_load_machines_cache', Mock(return_value=True)):
+            self.assertRaises(etcd.EtcdException, rtry, self.client.api_execute, '/', 'GET', params={'retry': rtry})
+
+        with patch.object(Client, '_do_http_request', Mock(side_effect=etcd.EtcdException)):
+            self.client._read_timeout = 0.01
             self.assertRaises(etcd.EtcdException, self.client.api_execute, '/', 'GET')
 
     def test_get_srv_record(self):
@@ -182,8 +185,12 @@ class TestClient(unittest.TestCase):
         self.client._get_machines_cache_from_dns('error', 2379)
 
     @patch.object(Client, 'machines')
-    def test__load_machines_cache(self, mock_machines):
+    def test__refresh_machines_cache(self, mock_machines):
-        mock_machines.__get__ = Mock(return_value=['http://localhost:2379'])
+        mock_machines.__get__ = Mock(side_effect=etcd.EtcdConnectionFailed)
+        self.assertIsNone(self.client._refresh_machines_cache())
+        self.assertRaises(etcd.EtcdException, self.client._refresh_machines_cache, True)
+
+    def test__load_machines_cache(self):
         self.client._config = {}
         self.assertRaises(Exception, self.client._load_machines_cache)
         self.client._config = {'srv': 'blabla'}

tests/test_ha.py

@@ -3,7 +3,7 @@ import etcd
 import os
 import sys
 
-from mock import Mock, MagicMock, PropertyMock, patch
+from mock import Mock, MagicMock, PropertyMock, patch, mock_open
 from patroni.config import Config
 from patroni.dcs import Cluster, ClusterConfig, Failover, Leader, Member, get_dcs, SyncState, TimelineHistory
 from patroni.dcs.etcd import Client
@@ -17,6 +17,7 @@ from patroni.postgresql.rewind import Rewind
 from patroni.postgresql.slots import SlotsHandler
 from patroni.utils import tzutc
 from patroni.watchdog import Watchdog
+from six.moves import builtins
 
 from . import PostgresInit, MockPostmaster, psycopg2_connect, requests_get
 from .test_etcd import socket_getaddrinfo, etcd_read, etcd_write
@@ -152,9 +153,11 @@ def run_async(self, func, args=()):
 @patch.object(Postgresql, 'is_leader', Mock(return_value=True))
 @patch.object(Postgresql, 'timeline_wal_position', Mock(return_value=(1, 10, 1)))
 @patch.object(Postgresql, '_cluster_info_state_get', Mock(return_value=3))
-@patch.object(Postgresql, 'call_nowait', Mock(return_value=True))
 @patch.object(Postgresql, 'data_directory_empty', Mock(return_value=False))
-@patch.object(Postgresql, 'controldata', Mock(return_value={'Database system identifier': SYSID}))
+@patch.object(Postgresql, 'controldata', Mock(return_value={
+    'Database system identifier': SYSID,
+    'Database cluster state': 'shut down',
+    'Latest checkpoint location': '0/12345678'}))
 @patch.object(SlotsHandler, 'sync_replication_slots', Mock())
 @patch.object(ConfigHandler, 'append_pg_hba', Mock())
 @patch.object(ConfigHandler, 'write_pgpass', Mock(return_value={}))
@@ -163,7 +166,7 @@ def run_async(self, func, args=()):
 @patch.object(Postgresql, 'query', Mock())
 @patch.object(Postgresql, 'checkpoint', Mock())
 @patch.object(CancellableSubprocess, 'call', Mock(return_value=0))
-@patch.object(Postgresql, 'get_local_timeline_lsn_from_replication_connection', Mock(return_value=[2, 10]))
+@patch.object(Postgresql, 'get_replica_timeline', Mock(return_value=2))
 @patch.object(Postgresql, 'get_master_timeline', Mock(return_value=2))
 @patch.object(ConfigHandler, 'restore_configuration_files', Mock())
 @patch.object(etcd.Client, 'write', etcd_write)
@@ -172,6 +175,7 @@ def run_async(self, func, args=()):
 @patch('patroni.postgresql.polling_loop', Mock(return_value=range(1)))
 @patch('patroni.async_executor.AsyncExecutor.busy', PropertyMock(return_value=False))
 @patch('patroni.async_executor.AsyncExecutor.run_async', run_async)
+@patch('patroni.postgresql.rewind.Thread', Mock())
 @patch('subprocess.call', Mock(return_value=0))
 @patch('time.sleep', Mock())
 class TestHa(PostgresInit):
@@ -198,6 +202,7 @@ class TestHa(PostgresInit):
         self.p.last_operation = Mock(side_effect=PostgresConnectionException(''))
         self.assertTrue(self.ha.update_lock(True))
 
+    @patch.object(Postgresql, 'received_timeline', Mock(return_value=None))
     def test_touch_member(self):
         self.p.timeline_wal_position = Mock(return_value=(0, 1, 0))
         self.p.replica_cached_timeline = Mock(side_effect=Exception)
@@ -253,7 +258,7 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader()
         self.assertEqual(self.ha.run_cycle(), 'starting as readonly because i had the session lock')
 
-    @patch.object(Postgresql, 'fix_cluster_state', Mock())
+    @patch.object(Rewind, 'ensure_clean_shutdown', Mock())
     def test_crash_recovery(self):
         self.p.is_running = false
         self.p.controldata = lambda: {'Database cluster state': 'in production', 'Database system identifier': SYSID}
@@ -689,13 +694,19 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_with_leader(Failover(0, '', self.p.name, None))
         self.assertEqual(self.ha.run_cycle(), 'PAUSE: waiting to become master after promote...')
 
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', mock_open(read_data='1\t0/40159C0\tno recovery target specified\n'))
     def test_process_healthy_standby_cluster_as_standby_leader(self):
         self.p.is_leader = false
         self.p.name = 'leader'
         self.ha.cluster = get_standby_cluster_initialized_with_only_leader()
         self.p.config.check_recovery_conf = Mock(return_value=(False, False))
+        self.ha._leader_timeline = 1
         self.assertEqual(self.ha.run_cycle(), 'promoted self to a standby leader because i had the session lock')
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am the standby leader with the lock')
+        self.p.set_role('replica')
+        self.p.config.check_recovery_conf = Mock(return_value=(True, False))
+        self.assertEqual(self.ha.run_cycle(), 'promoted self to a standby leader because i had the session lock')
 
     def test_process_healthy_standby_cluster_as_cascade_replica(self):
         self.p.is_leader = false
@@ -1006,6 +1017,8 @@ class TestHa(PostgresInit):
         self.ha._disable_sync = False
         self.assertEqual(self.ha.get_effective_tags(), {'foo': 'bar'})
 
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', Mock(side_effect=Exception))
     def test_restore_cluster_config(self):
         self.ha.cluster.config.data.clear()
         self.ha.has_lock = true
@@ -1037,7 +1050,9 @@ class TestHa(PostgresInit):
         # will not say bootstrap from leader as replica can't self elect
         self.assertEqual(self.ha.run_cycle(), "trying to bootstrap from replica 'other'")
 
-    @patch('psycopg2.connect', psycopg2_connect)
+    @patch('patroni.postgresql.mtime', Mock(return_value=1588316884))
+    @patch.object(builtins, 'open', mock_open(read_data=('1\t0/40159C0\tno recovery target specified\n\n'
+                                                         '2\t1/40159C0\tno recovery target specified\n')))
     def test_update_cluster_history(self):
         self.ha.has_lock = true
         self.ha.cluster.is_unlocked = false
@@ -1068,3 +1083,8 @@ class TestHa(PostgresInit):
         self.ha.cluster = get_cluster_initialized_without_leader(leader=True, cluster_config=config)
         self.ha.has_lock = true
         self.assertEqual(self.ha.run_cycle(), 'no action.  i am the leader with the lock')
+
+    @patch.object(Cluster, 'has_member', true)
+    def test_run_cycle(self):
+        self.ha.dcs.touch_member = Mock(side_effect=DCSError('foo'))
+        self.assertEqual(self.ha.run_cycle(), 'Unexpected exception raised, please report it as a BUG')

tests/test_kubernetes.py

@@ -8,7 +8,7 @@ from threading import Thread
 from . import SleepException
 
 
-def mock_list_namespaced_config_map(self, *args, **kwargs):
+def mock_list_namespaced_config_map(*args, **kwargs):
     metadata = {'resource_version': '1', 'labels': {'f': 'b'}, 'name': 'test-config',
                 'annotations': {'initialize': '123', 'config': '{}'}}
     items = [k8s_client.V1ConfigMap(metadata=k8s_client.V1ObjectMeta(**metadata))]
@@ -22,72 +22,72 @@ def mock_list_namespaced_config_map(self, *args, **kwargs):
     return k8s_client.V1ConfigMapList(metadata=metadata, items=items, kind='ConfigMapList')
 
 
-def mock_list_namespaced_pod(self, *args, **kwargs):
+def mock_list_namespaced_endpoints(*args, **kwargs):
-    metadata = k8s_client.V1ObjectMeta(resource_version='1', name='p-0', annotations={'status': '{}'})
+    target_ref = k8s_client.V1ObjectReference(kind='Pod', resource_version='10', name='p-0',
-    items = [k8s_client.V1Pod(metadata=metadata)]
+                                              namespace='default', uid='964dfeae-e79b-4476-8a5a-1920b5c2a69d')
+    address0 = k8s_client.V1EndpointAddress(ip='10.0.0.0', target_ref=target_ref)
+    address1 = k8s_client.V1EndpointAddress(ip='10.0.0.1')
+    port = k8s_client.V1EndpointPort(port=5432, name='postgresql', protocol='TCP')
+    subset = k8s_client.V1EndpointSubset(addresses=[address1, address0], ports=[port])
+    metadata = k8s_client.V1ObjectMeta(resource_version='1', labels={'f': 'b'}, name='test',
+                                       annotations={'optime': '1234', 'leader': 'p-0', 'ttl': '30s'})
+    endpoint = k8s_client.V1Endpoints(subsets=[subset], metadata=metadata)
+    metadata = k8s_client.V1ObjectMeta(resource_version='1')
+    return k8s_client.V1EndpointsList(metadata=metadata, items=[endpoint], kind='V1EndpointsList')
+
+
+def mock_list_namespaced_pod(*args, **kwargs):
+    metadata = k8s_client.V1ObjectMeta(resource_version='1', name='p-0', annotations={'status': '{}'},
+                                       uid='964dfeae-e79b-4476-8a5a-1920b5c2a69d')
+    status = k8s_client.V1PodStatus(pod_ip='10.0.0.0')
+    spec = k8s_client.V1PodSpec(hostname='p-0', node_name='kind-control-plane', containers=[])
+    items = [k8s_client.V1Pod(metadata=metadata, status=status, spec=spec)]
     return k8s_client.V1PodList(items=items, kind='PodList')
 
 
-def mock_config_map(*args, **kwargs):
+def mock_namespaced_kind(*args, **kwargs):
     mock = Mock()
     mock.metadata.resource_version = '2'
     return mock
 
-@patch('socket.TCP_KEEPIDLE', 4, create=True)
+
-@patch('socket.TCP_KEEPINTVL', 5, create=True)
+class BaseTestKubernetes(unittest.TestCase):
-@patch('socket.TCP_KEEPCNT', 6, create=True)
-@patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map', mock_config_map)
-@patch.object(k8s_client.CoreV1Api, 'create_namespaced_config_map', mock_config_map)
-@patch('kubernetes.client.api_client.ThreadPool', Mock(), create=True)
-@patch.object(Thread, 'start', Mock())
-class TestKubernetes(unittest.TestCase):
 
     @patch('socket.TCP_KEEPIDLE', 4, create=True)
     @patch('socket.TCP_KEEPINTVL', 5, create=True)
     @patch('socket.TCP_KEEPCNT', 6, create=True)
     @patch('kubernetes.config.load_kube_config', Mock())
-    @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('kubernetes.client.api_client.ThreadPool', Mock(), create=True)
     @patch.object(Thread, 'start', Mock())
-    def setUp(self):
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod)
-        self.k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0',
+    @patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map)
-                             'loop_wait': 10, 'retry_timeout': 10, 'labels': {'f': 'b'}})
+    def setUp(self, config=None):
+        config = config or {}
+        config.update(ttl=30, scope='test', name='p-0', loop_wait=10, retry_timeout=10, labels={'f': 'b'})
+        self.k = Kubernetes(config)
         self.assertRaises(AttributeError, self.k._pods._build_cache)
         self.k._pods._is_ready = True
         self.assertRaises(AttributeError, self.k._kinds._build_cache)
         self.k._kinds._is_ready = True
         self.k.get_cluster()
 
+
+@patch.object(k8s_client.CoreV1Api, 'patch_namespaced_config_map', mock_namespaced_kind)
+class TestKubernetesConfigMaps(BaseTestKubernetes):
+
     @patch('time.time', Mock(side_effect=[1, 10.9, 100]))
     def test__wait_caches(self):
         self.k._pods._is_ready = False
         with self.k._condition:
             self.assertRaises(RetryFailedError, self.k._wait_caches)
 
+    @patch('time.time', Mock(return_value=time.time() + 100))
     def test_get_cluster(self):
-        with patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map), \
+        self.k.get_cluster()
-                patch.object(k8s_client.CoreV1Api, 'list_namespaced_pod', mock_list_namespaced_pod), \
-                patch('time.time', Mock(return_value=time.time() + 31)):
-            self.k.get_cluster()
 
         with patch.object(Kubernetes, '_wait_caches', Mock(side_effect=Exception)):
             self.assertRaises(KubernetesError, self.k.get_cluster)
 
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
-    def test_update_leader(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'loop_wait': 10, 'retry_timeout': 10,
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
-        self.assertIsNotNone(k.update_leader('123'))
-
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', Mock())
-    def test_update_leader_with_restricted_access(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'loop_wait': 10, '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'
@@ -101,8 +101,9 @@ class TestKubernetes(unittest.TestCase):
     def test_set_config_value(self):
         self.k.set_config_value('{}')
 
-    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', Mock(return_value=True))
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod')
-    def test_touch_member(self):
+    def test_touch_member(self, mock_patch_namespaced_pod):
+        mock_patch_namespaced_pod.return_value.metadata.resource_version = '10'
         self.k.touch_member({'role': 'replica'})
         self.k._name = 'p-1'
         self.k.touch_member({'state': 'running', 'role': 'replica'})
@@ -112,7 +113,7 @@ class TestKubernetes(unittest.TestCase):
         self.k.initialize()
 
     def test_delete_leader(self):
-        self.k.delete_leader()
+        self.k.delete_leader(1)
 
     def test_cancel_initialization(self):
         self.k.cancel_initialization()
@@ -122,14 +123,6 @@ class TestKubernetes(unittest.TestCase):
     def test_delete_cluster(self):
         self.k.delete_cluster()
 
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints',
-                  Mock(side_effect=[k8s_client.rest.ApiException(502, ''), k8s_client.rest.ApiException(500, '')]))
-    def test_delete_sync_state(self):
-        k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0', 'loop_wait': 10, 'retry_timeout': 10,
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
-        self.assertFalse(k.delete_sync_state())
-
     def test_watch(self):
         self.k.set_ttl(10)
         self.k.watch(None, 0)
@@ -138,31 +131,58 @@ class TestKubernetes(unittest.TestCase):
     def test_set_history_value(self):
         self.k.set_history_value('{}')
 
-    @patch('kubernetes.config.load_kube_config', Mock())
+
-    @patch('patroni.dcs.kubernetes.ObjectCache', Mock())
+class TestKubernetesEndpoints(BaseTestKubernetes):
-    @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, 'list_namespaced_endpoints', mock_list_namespaced_endpoints)
+    def setUp(self, config=None):
+        super(TestKubernetesEndpoints, self).setUp({'use_endpoints': True, 'pod_ip': '10.0.0.0'})
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints')
+    def test_update_leader(self, mock_patch_namespaced_endpoints):
+        self.assertIsNotNone(self.k.update_leader('123'))
+        args = mock_patch_namespaced_endpoints.call_args[0]
+        self.assertEqual(args[2].subsets[0].addresses[0].target_ref.resource_version, '10')
+        self.k._kinds._object_cache['test'].subsets[:] = []
+        self.assertIsNotNone(self.k.update_leader('123'))
+        self.k._kinds._object_cache['test'].metadata.annotations['leader'] = 'p-1'
+        self.assertFalse(self.k.update_leader('123'))
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints', mock_namespaced_kind)
+    def test_update_leader_with_restricted_access(self):
+        self.assertIsNotNone(self.k.update_leader('123', True))
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_endpoints')
+    def test__update_leader_with_retry(self, mock_patch):
+        mock_patch.side_effect = k8s_client.rest.ApiException(502, '')
+        self.assertFalse(self.k.update_leader('123'))
+        mock_patch.side_effect = RetryFailedError('')
+        self.assertFalse(self.k.update_leader('123'))
+        mock_patch.side_effect = k8s_client.rest.ApiException(409, '')
+        with patch('time.time', Mock(side_effect=[0, 100, 200])):
+            self.assertFalse(self.k.update_leader('123'))
+        with patch('time.sleep', Mock()):
+            self.assertFalse(self.k.update_leader('123'))
+            mock_patch.side_effect = [k8s_client.rest.ApiException(409, ''), mock_namespaced_kind()]
+            self.k._kinds._object_cache['test'].metadata.resource_version = '2'
+            self.assertIsNotNone(self.k._update_leader_with_retry({}, '1', []))
+
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints',
+                  Mock(side_effect=[k8s_client.rest.ApiException(500, ''), k8s_client.rest.ApiException(502, '')]))
+    def test_delete_sync_state(self):
+        self.assertFalse(self.k.delete_sync_state())
+
+    @patch.object(k8s_client.CoreV1Api, 'patch_namespaced_pod', mock_namespaced_kind)
+    @patch.object(k8s_client.CoreV1Api, 'create_namespaced_endpoints', mock_namespaced_kind)
     @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', 'loop_wait': 10, 'retry_timeout': 10,
+        self.assertIsNotNone(self.k.patch_or_create_config({'foo': 'bar'}))
-                        'labels': {'f': 'b'}, 'use_endpoints': True, 'pod_ip': '10.0.0.0'})
+        self.assertIsNotNone(self.k.patch_or_create_config({'foo': 'bar'}))
-        self.assertIsNotNone(k.patch_or_create_config({'foo': 'bar'}))
+        self.k.touch_member({'state': 'running', 'role': 'replica'})
-        self.assertIsNotNone(k.patch_or_create_config({'foo': 'bar'}))
-        k.touch_member({'state': 'running', 'role': 'replica'})
 
 
-class TestCacheBuilder(unittest.TestCase):
+class TestCacheBuilder(BaseTestKubernetes):
-
-    @patch('socket.TCP_KEEPIDLE', 4, create=True)
-    @patch('socket.TCP_KEEPINTVL', 5, create=True)
-    @patch('socket.TCP_KEEPCNT', 6, create=True)
-    @patch('kubernetes.config.load_kube_config', Mock())
-    @patch('kubernetes.client.api_client.ThreadPool', Mock(), create=True)
-    @patch.object(Thread, 'start', Mock())
-    def setUp(self):
-        self.k = Kubernetes({'ttl': 30, 'scope': 'test', 'name': 'p-0',
-                             'loop_wait': 10, 'retry_timeout': 10, 'labels': {'f': 'b'}})
 
     @patch.object(k8s_client.CoreV1Api, 'list_namespaced_config_map', mock_list_namespaced_config_map)
     @patch('patroni.dcs.kubernetes.ObjectCache._watch')

tests/test_postgresql.py

@@ -93,7 +93,7 @@ class TestPostgresql(BaseTestPostgresql):
     @patch('subprocess.call', Mock(return_value=0))
     @patch('os.rename', Mock())
     @patch('patroni.postgresql.CallbackExecutor', Mock())
-    @patch.object(Postgresql, 'get_major_version', Mock(return_value=120000))
+    @patch.object(Postgresql, 'get_major_version', Mock(return_value=130000))
     @patch.object(Postgresql, 'is_running', Mock(return_value=True))
     def setUp(self):
         super(TestPostgresql, self).setUp()
@@ -250,6 +250,10 @@ class TestPostgresql(BaseTestPostgresql):
             self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': conninfo.copy()})
             self.p.config.write_postgresql_conf()
             self.assertEqual(self.p.config.check_recovery_conf(None), (False, False))
+            with patch.object(Postgresql, 'primary_conninfo', Mock(return_value='host=1')):
+                mock_get_pg_settings.return_value['primary_slot_name'] = [
+                    'primary_slot_name', '', '', 'string', 'postmaster', self.p.config._postgresql_conf]
+                self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
 
     @patch.object(Postgresql, 'major_version', PropertyMock(return_value=120000))
     @patch.object(Postgresql, 'is_running', MockPostmaster)
@@ -267,6 +271,7 @@ class TestPostgresql(BaseTestPostgresql):
             self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
 
     @patch.object(Postgresql, 'major_version', PropertyMock(return_value=100000))
+    @patch.object(Postgresql, 'primary_conninfo', Mock(return_value='host=1'))
     def test__read_recovery_params_pre_v12(self):
         self.p.config.write_recovery_conf({'standby_mode': 'on', 'primary_conninfo': {'password': 'foo'}})
         self.assertEqual(self.p.config.check_recovery_conf(None), (True, True))
@@ -338,6 +343,11 @@ class TestPostgresql(BaseTestPostgresql):
         with patch.object(Postgresql, '_query', Mock(side_effect=RetryFailedError(''))):
             self.assertRaises(PostgresConnectionException, self.p.is_leader)
 
+    @patch.object(Postgresql, 'controldata',
+                  Mock(return_value={'Database cluster state': 'shut down', 'Latest checkpoint location': 'X/678'}))
+    def test_latest_checkpoint_location(self):
+        self.assertIsNone(self.p.latest_checkpoint_location())
+
     def test_reload(self):
         self.assertTrue(self.p.reload())
 
@@ -412,6 +422,10 @@ class TestPostgresql(BaseTestPostgresql):
                     pass
         os.makedirs(os.path.join(self.p.data_dir, 'foo'))
         _symlink('foo', os.path.join(self.p.data_dir, 'pg_wal'))
+        os.makedirs(os.path.join(self.p.data_dir, 'foo_tsp'))
+        pg_tblspc = os.path.join(self.p.data_dir, 'pg_tblspc')
+        os.makedirs(pg_tblspc)
+        _symlink('../foo_tsp', os.path.join(pg_tblspc, '12345'))
         self.p.remove_data_directory()
         open(self.p.data_dir, 'w').close()
         self.p.remove_data_directory()
@@ -665,44 +679,8 @@ class TestPostgresql(BaseTestPostgresql):
         mock_postmaster.signal_stop.assert_called()
         mock_postmaster.wait.assert_called()
 
-    def test_read_postmaster_opts(self):
-        m = mock_open(read_data='/usr/lib/postgres/9.6/bin/postgres "-D" "data/postgresql0" \
-"--listen_addresses=127.0.0.1" "--port=5432" "--hot_standby=on" "--wal_level=hot_standby" \
-"--wal_log_hints=on" "--max_wal_senders=5" "--max_replication_slots=5"\n')
-        with patch.object(builtins, 'open', m):
-            data = self.p.read_postmaster_opts()
-            self.assertEqual(data['wal_level'], 'hot_standby')
-            self.assertEqual(int(data['max_replication_slots']), 5)
-            self.assertEqual(data.get('D'), None)
-
-            m.side_effect = IOError
-            data = self.p.read_postmaster_opts()
-            self.assertEqual(data, dict())
-
-    @patch('psutil.Popen')
-    def test_single_user_mode(self, subprocess_popen_mock):
-        subprocess_popen_mock.return_value.wait.return_value = 0
-        self.assertEqual(self.p.single_user_mode('CHECKPOINT', {'archive_mode': 'on'}), 0)
-
-    @patch('os.listdir', Mock(side_effect=[OSError, ['a', 'b']]))
-    @patch('os.unlink', Mock(side_effect=OSError))
-    @patch('os.remove', Mock())
-    @patch('os.path.islink', Mock(side_effect=[True, False]))
-    @patch('os.path.isfile', Mock(return_value=True))
-    def test_cleanup_archive_status(self):
-        self.p.cleanup_archive_status()
-        self.p.cleanup_archive_status()
-
-    @patch('os.unlink', Mock())
-    @patch('os.listdir', Mock(return_value=[]))
-    @patch('os.path.isfile', Mock(return_value=True))
-    @patch.object(Postgresql, 'read_postmaster_opts', Mock(return_value={}))
-    @patch.object(Postgresql, 'single_user_mode', Mock(return_value=0))
-    def test_fix_cluster_state(self):
-        self.assertTrue(self.p.fix_cluster_state())
-
     def test_replica_cached_timeline(self):
-        self.assertEqual(self.p.replica_cached_timeline(1), 2)
+        self.assertEqual(self.p.replica_cached_timeline(2), 3)
 
     def test_get_master_timeline(self):
         self.assertEqual(self.p.get_master_timeline(), 1)
@@ -712,7 +690,6 @@ class TestPostgresql(BaseTestPostgresql):
         with patch.object(Postgresql, 'controldata',
                           Mock(return_value={'max_connections setting': '200',
                                              'max_worker_processes setting': '20',
-                                             'max_prepared_xacts setting': '100',
                                              'max_locks_per_xact setting': '100',
                                              'max_wal_senders setting': 10})):
             self.p.cancellable.cancel()
@@ -723,3 +700,9 @@ class TestPostgresql(BaseTestPostgresql):
     @patch('os.path.isfile', Mock(return_value=False))
     def test_pgpass_is_dir(self):
         self.assertRaises(PatroniException, self.setUp)
+
+    @patch.object(Postgresql, '_query', Mock(side_effect=RetryFailedError('')))
+    def test_received_timeline(self):
+        self.p.set_role('standby_leader')
+        self.p.reset_cluster_info_state()
+        self.assertRaises(PostgresConnectionException, self.p.received_timeline)

tests/test_rewind.py

@@ -1,12 +1,45 @@
-from mock import Mock, PropertyMock, patch
+from mock import Mock, PropertyMock, patch, mock_open
 
 from patroni.postgresql import Postgresql
 from patroni.postgresql.cancellable import CancellableSubprocess
 from patroni.postgresql.rewind import Rewind
+from six.moves import builtins
 
 from . import BaseTestPostgresql, MockCursor, psycopg2_connect
 
 
+class MockThread(object):
+
+    def __init__(self, target, args):
+        self._target = target
+        self._args = args
+
+    def start(self):
+        self._target(*self._args)
+
+
+def mock_cancellable_call(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'pg_rewind: error: could not open file ' +
+                                              b'"data/postgresql0/pg_xlog/000000010000000000000003": No such file')
+    return 1
+
+
+def mock_cancellable_call0(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'')
+    return 0
+
+
+def mock_cancellable_call1(*args, **kwargs):
+    communicate = kwargs.pop('communicate', None)
+    if isinstance(communicate, dict):
+        communicate.update(stdout=b'', stderr=b'')
+    return 1
+
+
 @patch('subprocess.call', Mock(return_value=0))
 @patch('psycopg2.connect', psycopg2_connect)
 class TestRewind(BaseTestPostgresql):
@@ -25,13 +58,23 @@ class TestRewind(BaseTestPostgresql):
         self.p.config._config['use_pg_rewind'] = False
         self.assertFalse(self.r.can_rewind)
 
-    @patch.object(CancellableSubprocess, 'call')
+    def test_pg_rewind(self):
-    def test_pg_rewind(self, mock_cancellable_subprocess_call):
         r = {'user': '', 'host': '', 'port': '', 'database': '', 'password': ''}
-        mock_cancellable_subprocess_call.return_value = 0
+        with patch.object(Postgresql, 'major_version', PropertyMock(return_value=130000)),\
-        self.assertTrue(self.r.pg_rewind(r))
+                patch.object(CancellableSubprocess, 'call', Mock(return_value=None)):
-        mock_cancellable_subprocess_call.side_effect = OSError
+            with patch('subprocess.check_output', Mock(return_value=b'boo')):
-        self.assertFalse(self.r.pg_rewind(r))
+                self.assertFalse(self.r.pg_rewind(r))
+            with patch('subprocess.check_output', Mock(side_effect=Exception)):
+                self.assertFalse(self.r.pg_rewind(r))
+
+        with patch.object(Postgresql, 'major_version', PropertyMock(return_value=120000)),\
+                patch('subprocess.check_output', Mock(return_value=b'foo %f %p %r %% % %')):
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call):
+                self.assertFalse(self.r.pg_rewind(r))
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call0):
+                self.assertTrue(self.r.pg_rewind(r))
+            with patch.object(CancellableSubprocess, 'call', mock_cancellable_call1):
+                self.assertFalse(self.r.pg_rewind(r))
 
     @patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
     def test__get_local_timeline_lsn(self):
@@ -39,14 +82,15 @@ class TestRewind(BaseTestPostgresql):
         with patch.object(Postgresql, 'controldata',
                           Mock(return_value={'Database cluster state': 'shut down in recovery',
                                              'Minimum recovery ending location': '0/0',
-                                             "Min recovery ending loc's timeline": '0'})):
+                                             "Min recovery ending loc's timeline": '0',
+                                             'Latest checkpoint location': '0/'})):
             self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
 
         with patch.object(Postgresql, 'is_running', Mock(return_value=True)):
-            with patch.object(MockCursor, 'fetchone', Mock(side_effect=[(False, ), Exception])):
+            with patch.object(MockCursor, 'fetchone', Mock(side_effect=[(0, 0, 1, 1,), Exception])):
                 self.r.rewind_or_reinitialize_needed_and_possible(self.leader)
 
-    @patch.object(CancellableSubprocess, 'call', Mock(return_value=0))
+    @patch.object(CancellableSubprocess, 'call', mock_cancellable_call)
     @patch.object(Postgresql, 'checkpoint', side_effect=['', '1'],)
     @patch.object(Postgresql, 'stop', Mock(return_value=False))
     @patch.object(Postgresql, 'start', Mock())
@@ -72,11 +116,19 @@ class TestRewind(BaseTestPostgresql):
         with patch.object(Postgresql, 'is_running', Mock(return_value=True)):
             self.r.execute(self.leader)
 
+    @patch('patroni.postgresql.rewind.logger.info')
+    def test__log_master_history(self, mock_logger):
+        history = [[n, n, ''] for n in range(1, 10)]
+        self.r._log_master_history(history, 1)
+        expected = '\n'.join(['{0}\t0/{0}\t'.format(n) for n in range(1, 4)] + ['...', '9\t0/9\t'])
+        self.assertEqual(mock_logger.call_args[0][1], expected)
+
     @patch.object(Postgresql, 'start', Mock())
     @patch.object(Rewind, 'can_rewind', PropertyMock(return_value=True))
-    @patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(2, '40159C1')))
+    @patch.object(Rewind, '_get_local_timeline_lsn')
     @patch.object(Rewind, 'check_leader_is_not_in_recovery')
-    def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery):
+    def test__check_timeline_and_lsn(self, mock_check_leader_is_not_in_recovery, mock_get_local_timeline_lsn):
+        mock_get_local_timeline_lsn.return_value = (True, 2, 67197377)
         mock_check_leader_is_not_in_recovery.return_value = False
         self.r.trigger_check_diverged_lsn()
         self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
@@ -88,20 +140,91 @@ class TestRewind(BaseTestPostgresql):
         with patch('psycopg2.connect', Mock(side_effect=Exception)):
             self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.r.trigger_check_diverged_lsn()
-        with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 2, '0/0'), ('', b'3\t0/40159C0\tn\n')])):
+        with patch.object(MockCursor, 'fetchone', Mock(side_effect=[('', 3, '0/0'), ('', b'3\t0/40159C0\tn\n')])):
             self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
         self.r.trigger_check_diverged_lsn()
         with patch.object(MockCursor, 'fetchone', Mock(return_value=('', 1, '0/0'))):
-            with patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(1, '0/0'))):
+            with patch.object(Rewind, '_get_local_timeline_lsn', Mock(return_value=(True, 1, '0/0'))):
                 self.assertFalse(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
             self.r.trigger_check_diverged_lsn()
             self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
 
+        self.r.reset_state()
+        self.r.trigger_check_diverged_lsn()
+        mock_get_local_timeline_lsn.return_value = (False, 2, 67296664)
+        self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+
+        with patch('subprocess.Popen') as mock_popen:
+            mock_popen.return_value.communicate.return_value = (
+                b'0, lsn: 0/040159C1, prev 0/\n',
+                b'pg_waldump: fatal: error in WAL record at 0/40159C1: invalid record length at /: wanted 24, got 0\n'
+            )
+            self.r.reset_state()
+            self.r.trigger_check_diverged_lsn()
+            mock_get_local_timeline_lsn.return_value = (False, 2, 67197377)
+            self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+            self.r.reset_state()
+            self.r.trigger_check_diverged_lsn()
+            mock_popen.side_effect = Exception
+            self.assertTrue(self.r.rewind_or_reinitialize_needed_and_possible(self.leader))
+
     @patch.object(MockCursor, 'fetchone', Mock(side_effect=[(True,), Exception]))
     def test_check_leader_is_not_in_recovery(self):
         self.r.check_leader_is_not_in_recovery()
         self.r.check_leader_is_not_in_recovery()
 
-    @patch.object(Postgresql, 'controldata', Mock(return_value={"Latest checkpoint's TimeLineID": 1}))
+    def test_read_postmaster_opts(self):
-    def test_check_for_checkpoint_after_promote(self):
+        m = mock_open(read_data='/usr/lib/postgres/9.6/bin/postgres "-D" "data/postgresql0" \
-        self.r.check_for_checkpoint_after_promote()
+"--listen_addresses=127.0.0.1" "--port=5432" "--hot_standby=on" "--wal_level=hot_standby" \
+"--wal_log_hints=on" "--max_wal_senders=5" "--max_replication_slots=5"\n')
+        with patch.object(builtins, 'open', m):
+            data = self.r.read_postmaster_opts()
+            self.assertEqual(data['wal_level'], 'hot_standby')
+            self.assertEqual(int(data['max_replication_slots']), 5)
+            self.assertEqual(data.get('D'), None)
+
+            m.side_effect = IOError
+            data = self.r.read_postmaster_opts()
+            self.assertEqual(data, dict())
+
+    @patch('psutil.Popen')
+    def test_single_user_mode(self, subprocess_popen_mock):
+        subprocess_popen_mock.return_value.wait.return_value = 0
+        subprocess_popen_mock.return_value.communicate.return_value = ('', '')
+        self.assertEqual(self.r.single_user_mode({'input': 'CHECKPOINT'}, {'archive_mode': 'on'}), 0)
+
+    @patch('os.listdir', Mock(side_effect=[OSError, ['a', 'b']]))
+    @patch('os.unlink', Mock(side_effect=OSError))
+    @patch('os.remove', Mock())
+    @patch('os.path.islink', Mock(side_effect=[True, False]))
+    @patch('os.path.isfile', Mock(return_value=True))
+    def test_cleanup_archive_status(self):
+        self.r.cleanup_archive_status()
+        self.r.cleanup_archive_status()
+
+    @patch('os.unlink', Mock())
+    @patch('os.listdir', Mock(return_value=[]))
+    @patch('os.path.isfile', Mock(return_value=True))
+    @patch.object(Rewind, 'read_postmaster_opts', Mock(return_value={}))
+    @patch.object(Rewind, 'single_user_mode', Mock(return_value=0))
+    def test_ensure_clean_shutdown(self):
+        self.assertTrue(self.r.ensure_clean_shutdown())
+
+    @patch('patroni.postgresql.rewind.Thread', MockThread)
+    @patch.object(Postgresql, 'controldata')
+    @patch.object(Postgresql, 'checkpoint')
+    def test_ensure_checkpoint_after_promote(self, mock_checkpoint, mock_controldata):
+        mock_checkpoint.return_value = None
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())
+
+        self.r.reset_state()
+        mock_controldata.return_value = {"Latest checkpoint's TimeLineID": 1}
+        mock_checkpoint.side_effect = Exception
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())
+
+        self.r.reset_state()
+        mock_controldata.side_effect = TypeError
+        self.r.ensure_checkpoint_after_promote(Mock())
+        self.r.ensure_checkpoint_after_promote(Mock())

tests/test_zookeeper.py

@@ -150,7 +150,7 @@ class TestZooKeeper(unittest.TestCase):
 
     def test_get_cluster(self):
         self.assertRaises(ZooKeeperError, self.zk.get_cluster)
-        cluster = self.zk.get_cluster()
+        cluster = self.zk.get_cluster(True)
         self.assertIsInstance(cluster.leader, Leader)
         self.zk.touch_member({'foo': 'foo'})