Re: PgFDW connection invalidation by ALTER SERVER/ALTER USER MAPPING

Finally, I added new TAP test library PsqlSession.

At Tue, 18 Jul 2017 18:12:13 +0900 (Tokyo Standard Time), Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote in <20170718(dot)181213(dot)206979369(dot)horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp>
> > * How about some regression test cases? You couldn't really exercise
> > cross-session invalidation easily, but I don't think you need to.
>
> Ha Ha. You got me. I will add some test cases for this in the
> next version. Thanks.

Here it is. First I tried this using ordinary regression
framework but the effect of this patch is shown only in log and
it contains variable parts so I gave up it before trying more
complex way.

Next I tried existing TAP test but this test needs continuous
session to achieve alternating operation on two sessions but
PostgresNode::psql doesn't offer such a functionality.

Finally, I added a new TAP test library PsqlSession. It offers
interactive psql sessions. Then added a simple test to
postgres_fdw using it.

The first patch is the PsqlSession.pm and the second is the new
test for postgres_fdw.

- The current PsqlSession is quite fragile but seems working
enough for this usage at the present.

- I'm afraid this might not work on Windows according to the
manpage of IPC::Run, but I haven't confirmed yet.

http://search.cpan.org/~toddr/IPC-Run-0.96/lib/IPC/Run.pm#Win32_LIMITATIONS

Any comment or suggestions are welcome.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center