Re: Time to drop plpython2?

Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> writes:
> On 11.01.22 17:06, Tom Lane wrote:
>> Nonetheless, we need to make a recommendation to the
>> buildfarm owners about what's the minimum python3 version we intend
>> to support going forward.

> Well, the minimum supported version has always been the oldest version
> that actually works. I don't think we ever said, we support >= X, even
> though < X still actually works, about any dependency.

The concern I have is how do we know what "actually works", if we're
not testing it? installation.sgml currently promises python2 >= 2.6,
and we know that that works because we have 2.6 in the buildfarm.
It also promises python3 >= 3.1, but we have no buildfarm animals
testing anything older than 3.4.3, so I don't think that promise
is worth the electrons it's written on. Furthermore, if the meson
conversion forces people to update their python3 to something newer,
there will probably be no testing of plpython against anything older
than what meson requires.

> I don't care much to tie this to Meson right now. Meson might well move
> to 3.8 next week and ruin this whole scheme.

Wouldn't be a problem unless our build scripts require that newer
version of meson. Andres mentioned earlier that we should be able
to run with some older meson versions that only require python 3.5
or so, so I'm hoping we can end up with directives like "use meson
X or later and python 3.5 or later".

> I'm okay with issuing some sort of recommendation for what is reasonable
> to test, and 3.5 or 3.6 seems like a good cutoff, considering what LTS
> OS currently ship. But I'm not sure if that is the same as "support".

Well, I'll see about putting 3.5 on my dinosaurs, and hope I don't
have to do it over.

Anyway, getting back to the point: I think we should notify the
owners ASAP and set a 30-day deadline. We should try to get this
done before the March CF starts, so it's too late for a 60-day
grace period. In any case, the worst-case scenario for an owner
is to disable --with-python until they have time to do an upgrade,
so it doesn't seem like a month is a big problem.

regards, tom lane