pg_autoctl show uri

pg_autoctl show uri - Show the postgres uri to use to connect to pg_auto_failover nodes

Synopsis

This command outputs the monitor or the coordinator Postgres URI to use from an application to connect to Postgres:

usage: pg_autoctl show uri  [ --pgdata --monitor --formation --json ]

  --pgdata      path to data directory
  --monitor     monitor uri
  --formation   show the coordinator uri of given formation
  --json        output data in the JSON format

Options

--pgdata

Location of the Postgres node being managed locally. Defaults to the environment variable PGDATA. Use --monitor to connect to a monitor from anywhere, rather than the monitor URI used by a local Postgres node managed with pg_autoctl.

--monitor

Postgres URI used to connect to the monitor. Must use the autoctl_node username and target the pg_auto_failover database name. It is possible to show the Postgres URI from the monitor node using the command pg_autoctl show uri.

Defaults to the value of the environment variable PG_AUTOCTL_MONITOR.

--formation

When --formation is used, lists the Postgres URIs of all known formations on the monitor.

--json

Output a JSON formatted data instead of a table formatted list.

Environment

PGDATA

Postgres directory location. Can be used instead of the --pgdata option.

PG_AUTOCTL_MONITOR

Postgres URI to connect to the monitor node, can be used instead of the --monitor option.

XDG_CONFIG_HOME

The pg_autoctl command stores its configuration files in the standard place XDG_CONFIG_HOME. See the XDG Base Directory Specification.

XDG_DATA_HOME

The pg_autoctl command stores its internal states files in the standard place XDG_DATA_HOME, which defaults to ~/.local/share. See the XDG Base Directory Specification.

Examples

$ pg_autoctl show uri
        Type |    Name | Connection String
-------------+---------+-------------------------------
     monitor | monitor | postgres://autoctl_node@localhost:5500/pg_auto_failover
   formation | default | postgres://localhost:5502,localhost:5503,localhost:5501/demo?target_session_attrs=read-write&sslmode=prefer

$ pg_autoctl show uri --formation monitor
postgres://autoctl_node@localhost:5500/pg_auto_failover

$ pg_autoctl show uri --formation default
postgres://localhost:5503,localhost:5502,localhost:5501/demo?target_session_attrs=read-write&sslmode=prefer

$ pg_autoctl show uri --json
[
 {
     "uri": "postgres://autoctl_node@localhost:5500/pg_auto_failover",
     "name": "monitor",
     "type": "monitor"
 },
 {
     "uri": "postgres://localhost:5503,localhost:5502,localhost:5501/demo?target_session_attrs=read-write&sslmode=prefer",
     "name": "default",
     "type": "formation"
 }
]

Multi-hosts Postgres connection strings

PostgreSQL since version 10 includes support for multiple hosts in its connection driver libpq, with the special target_session_attrs connection property.

This multi-hosts connection string facility allows applications to keep using the same stable connection string over server-side failovers. That’s why pg_autoctl show uri uses that format.