How to integrate with another application

Integrations , also known as “relations” are connections between two applications with compatible endpoints. These connections simplify the creation and management of users, passwords, and other shared data.

This guide shows how to integrate Charmed PostgreSQL with both charmed and non-charmed applications.

For developer information about how to integrate your own charmed application with PostgreSQL, see Development > How to integrate with your charm.

Integrate with a charmed application

Integrations with charmed applications are supported via the modern postgresql_client interface, and the legacy psql interface from the original version of the charm.

Note

You can see which existing charms are compatible with PostgreSQL in the Integrations tab.

To integrate with a charmed application that supports the postgresql_client interface, run

juju integrate postgresql:database <charm>

To remove the integration, run

juju remove-relation postgresql <charm>

Integrate with a non-charmed application

To integrate with an application outside of Juju, you must use the data-integrator charm to create the required credentials and endpoints.

Deploy data-integrator:

juju deploy data-integrator --config database-name=<name>

Integrate with PostgreSQL:

juju integrate data-integrator postgresql

Use the get-credentials action to retrieve credentials from data-integrator:

juju run data-integrator/leader get-credentials

Rotate application passwords

To rotate the passwords of users created for integrated applications, the integration should be removed and integrated again. This process will generate a new user and password for the application.

juju remove-relation <charm> postgresql
juju integrate <charm> postgresql

<charm> can be data-integrator in the case of connecting with a non-charmed application.

Internal operator user

The operator user is used internally by the Charmed PostgreSQL application. All user credentials are managed with Juju secrets.

See also

Request a custom username

Charms can request a custom username to be used in their relation with PostgreSQL 16.

The simplest way to test it is to use requested-entities-secret field via the data-integrator charm .

Example
$ juju deploy postgresql --channel 16/stable

$ juju add-secret myusername mylogin=mypassword
secret:d5l3do605d8c4b1gn9a0

$ juju deploy data-integrator --channel latest/edge --config database-name=mydbname --config requested-entities-secret=d5l3do605d8c4b1gn9a0
Deployed "data-integrator" from charm-hub charm "data-integrator", revision 307 in channel latest/edge on ubuntu@24.04/stable

$ juju grant-secret d5l3do605d8c4b1gn9a0 data-integrator

$ juju relate postgresql data-integrator

$ juju run data-integrator/leader get-credentials
...
postgresql:
  database: mydbname
  username: mylogin
  password: mypassword
  uris: postgresql://mylogin:mypassword@10.218.34.199:5432/mydbname
  version: "16.11"
  ...

$ psql postgresql://mylogin:mypassword@10.218.34.199:5432/mydbname -c "SELECT SESSION_USER, CURRENT_USER"
 session_user |       current_user        
--------------+---------------------------
 mylogin      | charmed_mydbname_owner
(1 row)

For more technical details, see the description of the postgresql_client interface