community.general.postgresql_slot – Add or remove replication slots from a PostgreSQL database

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Ansible/docs/2.10/collections/community/general/postgresql slot module


community.general.postgresql_slot – Add or remove replication slots from a PostgreSQL database

Note

This plugin is part of the community.general collection (version 1.3.2).

To install it use: ansible-galaxy collection install community.general.

To use it in a playbook, specify: community.general.postgresql_slot.


Synopsis

  • Add or remove physical or logical replication slots from a PostgreSQL database.

Requirements

The below requirements are needed on the host that executes this module.

  • psycopg2

Parameters

Parameter Choices/Defaults Comments

ca_cert

string

Specifies the name of a file containing SSL certificate authority (CA) certificate(s).

If the file exists, the server's certificate will be verified to be signed by one of these authorities.


aliases: ssl_rootcert

db

string

Name of database to connect to.


aliases: login_db

immediately_reserve

boolean

  • no

  • yes

Optional parameter that when yes specifies that the LSN for this replication slot be reserved immediately, otherwise the default, no, specifies that the LSN is reserved on the first connection from a streaming replication client.

Is available from PostgreSQL version 9.6.

Uses only with slot_type=physical.

Mutually exclusive with slot_type=logical.

login_host

string

Host running the database.

login_password

string

The password used to authenticate with.

login_unix_socket

string

Path to a Unix domain socket for local connections.

login_user

string

Default:

"postgres"

The username used to authenticate with.

name

string / required

Name of the replication slot to add or remove.


aliases: slot_name

output_plugin

string

Default:

"test_decoding"

All logical slots must indicate which output plugin decoder they're using.

This parameter does not apply to physical slots.

It will be ignored with slot_type=physical.

port

integer

Default:

5432

Database port to connect to.


aliases: login_port

session_role

string

Switch to session_role after connecting. The specified session_role must be a role that the current login_user is a member of.

Permissions checking for SQL commands is carried out as though the session_role were the one that had logged in originally.

slot_type

string

  • logical
  • physical

Slot type.

ssl_mode

string

  • allow
  • disable
  • prefer

  • require
  • verify-ca
  • verify-full

Determines whether or with what priority a secure SSL TCP/IP connection will be negotiated with the server.

See https://www.postgresql.org/docs/current/static/libpq-ssl.html for more information on the modes.

Default of prefer matches libpq default.

state

string

  • absent
  • present

The slot state.

state=present implies the slot must be present in the system.

state=absent implies the groups must be revoked from target_roles.

trust_input

boolean

added in 0.2.0 of community.general

  • no
  • yes

If no, check the value of session_role is potentially dangerous.

It makes sense to use no only when SQL injections via session_role are possible.



Notes

Note

  • Physical replication slots were introduced to PostgreSQL with version 9.4, while logical replication slots were added beginning with version 10.0.
  • The default authentication assumes that you are either logging in as or sudo’ing to the postgres account on the host.
  • To avoid “Peer authentication failed for user postgres” error, use postgres user as a become_user.
  • This module uses psycopg2, a Python PostgreSQL database adapter. You must ensure that psycopg2 is installed on the host before using this module.
  • If the remote host is the PostgreSQL server (which is the default case), then PostgreSQL must also be installed on the remote host.
  • For Ubuntu-based systems, install the postgresql, libpq-dev, and python-psycopg2 packages on the remote host before using this module.
  • The ca_cert parameter requires at least Postgres version 8.4 and psycopg2 version 2.4.3.


See Also

See also

PostgreSQL pg_replication_slots view reference
Complete reference of the PostgreSQL pg_replication_slots view.
PostgreSQL streaming replication protocol reference
Complete reference of the PostgreSQL streaming replication protocol documentation.
PostgreSQL logical replication protocol reference
Complete reference of the PostgreSQL logical replication protocol documentation.


Examples

- name: Create physical_one physical slot if doesn't exist
  become_user: postgres
  community.general.postgresql_slot:
    slot_name: physical_one
    db: ansible

- name: Remove physical_one slot if exists
  become_user: postgres
  community.general.postgresql_slot:
    slot_name: physical_one
    db: ansible
    state: absent

- name: Create logical_one logical slot to the database acme if doesn't exist
  community.general.postgresql_slot:
    name: logical_slot_one
    slot_type: logical
    state: present
    output_plugin: custom_decoder_one
    db: "acme"

- name: Remove logical_one slot if exists from the cluster running on another host and non-standard port
  community.general.postgresql_slot:
    name: logical_one
    login_host: mydatabase.example.org
    port: 5433
    login_user: ourSuperuser
    login_password: thePassword
    state: absent

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key Returned Description

name

string

always

Name of the slot


Sample:

physical_one

queries

string

always

List of executed queries.


Sample:

["SELECT pg_create_physical_replication_slot('physical_one', False, False)"]




Authors

  • John Scalia (@jscalia)
  • Andrew Klychkov (@Andersson007)
  • Thomas O’Donnell (@andytom)

© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.10/collections/community/general/postgresql_slot_module.html