postgres: `dbstrict` configuration parameter not honored (regression since 7.80.0)

[toadjaune]

Hi everyone !

Summary

Since version 7.80.0 of the agent, even setting dbstrict: true and disabling database autodiscovery, the postgresql connects to databases other than the one specified in dbname.

Affected versions

The following agent versions were tested :

• 7.79.2 : Works fine
• 7.80.0 : Affected
• 7.81.1 : Affected

Reproducer

This should be a minimal reproducer :

# /etc/conf.d/postgres.d/conf.yaml

instances:
  - dbm: true
    host: <server_hostname>
    port: 5432
    username: <username>
    password: <password>
    dbname: database_1
    dbstrict: true

Assuming there are 2 databases on the server (database_1 and database_2), with this configuration on one of the affected versions above, I can see the agent querying database_2 as well with pg_stat_activity. This, in turn, can block some postgres operations (such as dropping a database), because there are active sessions on said database.

Related issues

#24531 may be related, but I'm not certain.