Phabricator hosts need to be upgraded to bookworm now that PHP 8 support is in place
A placeholder task for discussing migrating Phabricator hosts from bullseye to bookworm.
This is pending Phorge support for PHP 8 as tracked in https://we.phorge.it/T15554
Since https://we.phorge.it/T15554, Phorge shouldn't spectacularly blow up anymore when running into a PHP8 issue. However after running PHPStan (static code analysis) I believe there's still quite some stuff to potentially fix in upstream, however those might be less common code paths.
A new upstream release 2024.35 is out and personally I'd prefer to wait with upgrading to Bookworm (PHP 8.2) at least until the next upstream release, probably also because I still have a bunch of PHP8.1 upstream fixes waiting to get merged.
I feel that once T386558 has been resolved this very task could be looked into. I have not ran into remaining PHP 8.x issues locally in Phorge lately but obviously I am not a bot ({{citation needed}}) entering every weird corner of an application either fuzzying or trying to harvest strings for an LLM.
There is T377889 (phab1005) which is separate new hardware. We can use it to test that without having to touch existing servers.
In T377889 we now managed to deploy phabricator with scap now..and installed PHP 8.
This let's us confirm if Phabricator works on bookworm and with PHP8.. which should unblock the upgrades of the phab hosts here.
Today's upgrade of the Phabricator production instance in T404134 included many PHP8 fixes in the codebase, so I am personally fine now with moving from Bullseye (PHP7) to Bookworm (PHP8).