Re: Using LibPq in TAP tests via FFI

On 2024-07-18 Th 6:51 PM, Thomas Munro wrote:
> On Wed, Jul 17, 2024 at 2:27 AM Andrew Dunstan<andrew(at)dunslane(dot)net> wrote:
>> Here's the latest version of this patch. It removes all use of
>> background_psql(). Instead it uses libpq's async interface, which seems
>> to me far more robust. There is one remaining use of interactive_psql(),
>> but that's reasonable as it's used for testing psql itself.
> This looks really nice! Works on my local FBSD machine.

cool

>
> I pushed it to CI, and mostly saw environmental problems unrelated to
> the patch, but you might be interested in the ASAN failure visible in
> the cores section:
>
> https://cirrus-ci.com/task/6607915962859520
>
> Unfortunately I can't see the interesting log messages, because it
> detected that the logs were still being appended to and declined to
> upload them. I think that means there must be subprocesses not being
> waited for somewhere?

I couldn't see anything obvious either.

>
>> I spent yesterday creating an XS wrapper for just the 19 libpq functions
>> used in Session.pm. It's pretty simple. I have it passing a very basic
>> test, but haven't tried plugging it into Session.pm yet.
> Neat. I guess the libpq FFI/XS piece looks the same to the rest of
> the test framework outside that module.

Yeah, that's the idea.

> It does sound pretty
> convenient if the patch just works™ on CI/BF without any environment
> changes, which I assume must be doable because we already build XS
> stuff in sr/pl/plperl. Looking forward to trying that version.

Still working on it. Meanwhile, here's a new version. It has some
cleanup and also tries to use Session objects instead of psql in simple
cases for safe_psql().

cheers

andrew

--
Andrew Dunstan
EDB:https://www.enterprisedb.com