Postgresql DatabaseWrapper does not allow to override ensure_timezone() function in derived classes

[Christian Hardenberg]

Description:

The function _configure_connection() in base.py of the postgresql DatabaseWrapper directly calls the local function ensure_timezone:

    def _configure_connection(self, connection):
        # This function is called from init_connection_state and from the
        # psycopg pool itself after a connection is opened. Make sure that
        # whatever is done here does not access anything on self aside from
        # variables.

        # Commit after setting the time zone.
        commit_tz = ensure_timezone(connection, self.ops, self.timezone_name)
        # Set the role on the connection. This is useful if the credential used
        # to login is not the same as the role that owns database resources. As
        # can be the case when using temporary or ephemeral credentials.
        role_name = self.settings_dict["OPTIONS"].get("assume_role")
        commit_role = ensure_role(connection, self.ops, role_name)

        return commit_role or commit_tz

Instead it should call the class method like this, which should have the same result, but allows overriding in derived classes:

        commit_tz = self.ensure_timezone()

Why it matters?
I am implementing a database wrapper for QuestDB, which implements the postgres-protocol, so it's useful to derive the wrapper from the postgres wrapper. I need to override some methods though, such as ensure_timezone, because the set_config function is not supported by QuestDB ("SELECT set_config('TimeZone', 'UTC', false)")

[Sarah Boyce]

Thank you! Agree we should make some kinda update here
Regression in fad334e1a9b54ea1acb8cce02a25934c5acfe99f (ref #33497)

Would you like to prepare a PR?

[Florian Apolloner]

Yes we can make it a class method (and init_connection_state + ensure_role) as well. Please ping me for a review once a PR is up.

[Sarah Boyce]

I haven't updated ensure_role to be a class method but I can

[nessita <124304+nessita@…>]

In 7380ac5:

Fixed #35688 -- Restored timezone and role setters to be PostgreSQL DatabaseWrapper methods.

Following the addition of PostgreSQL connection pool support in
Refs #33497, the methods for configuring the database role and timezone
were moved to module-level functions. This change prevented subclasses
of DatabaseWrapper from overriding these methods as needed, for example,
when creating wrappers for other PostgreSQL-based backends.

Thank you Christian Hardenberg for the report and to
Florian Apolloner and Natalia Bidart for the review.

Regression in fad334e1a9b54ea1acb8cce02a25934c5acfe99f.

Co-authored-by: Natalia <124304+nessita@…>

[Natalia <124304+nessita@…>]

In 26c0667:

[5.1.x] Fixed #35688 -- Restored timezone and role setters to be PostgreSQL DatabaseWrapper methods.

Following the addition of PostgreSQL connection pool support in
Refs #33497, the methods for configuring the database role and timezone
were moved to module-level functions. This change prevented subclasses
of DatabaseWrapper from overriding these methods as needed, for example,
when creating wrappers for other PostgreSQL-based backends.

Thank you Christian Hardenberg for the report and to
Florian Apolloner and Natalia Bidart for the review.

Regression in fad334e1a9b54ea1acb8cce02a25934c5acfe99f.

Co-authored-by: Natalia <124304+nessita@…>

Backport of 7380ac57340653854bc2cfe0ed80298cdac6061d from main.