"libpq" constraint of 14.12 seems needlessly high

[nikita-volkov]

Which leads to failed builds on systems that are compatible. E.g.,

...
checking for the PostgreSQL version... 14.11
checking if PostgreSQL version 14.11 is >= 14.12... no
configure: error: Library requirements (PostgreSQL) not met.
Error: [Cabal-7125]
Failed to build postgresql-libpq-configure-0.11 (which is required by hasql-1.8). See the build log above for details.

Judging by the official docs, pipelining is supported in libpq starting from version 14.

[phadej]

What's your system running 14.11? Could you upgrade the libpq?

Ubuntu Jammy has 14.13: https://packages.ubuntu.com/jammy/postgresql-14-asn1oid, and I picked 14.12 because that's one installed on GHA Windows CI.

I'm hesitant to use anything I don't test against. 14.13 is the last in 14. series, so perfectly I'd like to require that, unfortunately I have to allow 14.12 for now.

[nikita-volkov]

Locally I'm running on macOS via brew. It's not a problem to update.

In some situations however it's easier to avoid upgrading the lib than a system dependency. E.g., in my case at work I may have to go thru long communications with colleagues before that can be achieved. So I'm sure more people will be coming with the same request.

[phadej]

If Ubuntu LTS 22 managed to upgrade promptly to libpq-14.13, I'm quite convinced that the long communications doesn't need to be long. If corporate processes e.g. make it easier to have a local patch to (just released) postgresql-libpq than upgrading libpq (released before), i'm not sorry.

[nikita-volkov]

Ok. Up to you

[phadej]

• 14.13 is released recently, 2024-08-08.
• 14.12 2024-05-09
• 14.11 2024-02-08

Looks like PostgreSQL has 3 month minor release cycle.

---

I checked that

• debian bookworm atm bundles 15.8 released 2024-08-08
• fedora 40 bundles 16.4 also released 2024-08-08

so big distributions are promptly including the new minor releases.

---

GHA windows image https://github.com/actions/runner-images/blob/main/images/windows/Windows2022-Readme.md (atm) image version is 20240825.1.0, and includes 14.12 released 2024-05-09

---

Until there is technical reason why upgrade is not possible, I don't see a reason to relax lower bound. As far as I can see the postgresql version adoption is quite prompt in free software.

[echatav]

As far as I can see the postgresql version adoption is quite prompt in free software.

Unfortunately this does not appear to be the case, at least in the Haskell tooling ecosystem. See discussion here. Can we reopen this issue and lower the libpq constraint?

[phadej]

@echatav No. Current postgresql-libpq definitely needs postgres 14. (14.12 vs 14.11 is irrelevant if Hackage docbuilder has 13).

EDIT: For the context, I already waited with the pipelining patch (which requires more recent libpq) longer than some people wanted. I cannot make everyone happy; current setup is hopefully a middle ground. IMHO, Hackage docbuilder just needs people to keep it updated.