Regression test failures against PostgreSQL 19 beta

[harudini]

Hello,

I am running the pgpool2 4.7.2 regression test against PostgreSQL 19 beta.

Several tests were failing with the following error, so I set PGMAXPROTOCOLVERSION=3.0 in my environment as suggested.
https://wiki.postgresql.org/wiki/Grease

It resolved some of the failures, but the following tests are still failing: 020, 021, 022, 023, 024, and 040.
Is this expected given that PG19 is still in its beta cycle, or is there another temporary setting I should apply?

Log for one of the failing test (020.allow_clear_text_frontend_auth):

scram_user authenticated setup successfully
md5 authenticated setup successfully
scram_user authenticated successfully
psql: error: connection to server at "127.0.0.1", port 11000 failed: FATAL: unable to get session context
md5 authentication failed
Trying wrong passwords now
psql: error: connection to server at "127.0.0.1", port 11000 failed: ERROR: backend authentication failed
DETAIL: backend response with kind 'E' when expecting 'R'
wrong password rejected properly for scram auth
psql: error: connection to server at "127.0.0.1", port 11000 failed: ERROR: authentication failed
DETAIL: password authentication failed for user "md5_user"
wrong password rejected properly for md5 auth

[tatsuo-ishii]

Thanks for the report. It turned out that there's a bug in pgpool authentication module (pool_do_auth). From PostgreSQL 19, backend sends a notice message "authenticated with an MD5-encrypted password" if MD5 auth is used. Unfortunately it exercises an untested code path in pool_do_auth. It calls SimpleForwardToFrontend to forward the notice message to frontend. Unfortunately calling it in authentication phase is wrong, since "session contest" is not established. If the session context is not established, SimpleForwardToFrontend
fails with FATAL and you see "backend response with kind 'E' when expecting 'R'" error.. Attached is a patch to fix the bug. Instead of calling SimpleForwardToFrontend, a simplified version "forward_message_frontend" is added. Can you try it out?

fix_pool_do_auth.patch

[tatsuo-ishii]

Slightly modified version of the patch (function name change). I plan to commit the patch.

v2-0001-Fix-pool_do_auth.patch

[harudini]

Thank you for the patch!
I tested it and confirmed it resolves the failing tests. All tests passing now.

[tatsuo-ishii]

Thank you for the test! I have pushed to all supported branches along with a regression test.