Re: Writing new unit tests with PostgresNode

On 22 February 2016 at 15:41, Michael Paquier <michael(dot)paquier(at)gmail(dot)com>
wrote:

>
> >> > Sound about right? I can tidy that up a bit and turn it into a README
> >> > and
> >> > add a reference to that to the public tap docs to tell users where to
> go
> >> > if
> >> > they want to write more tests.
> >>
> >> Yes, please.
> >
> > Will do that now.
>
> This is definitely independent from the efforts of the other patches.
>

Done.

I got a bit carried away and added:

- src/test/perl/README
- src/test/README
- src/test/modules/README
- POD for src/test/perl/PostgresNode.pm
- $node->info() function (that just returns what dump_info() printed, but
as a string
- $node->backup(...) support for passing -R to pg_basebackup
- $node->backup(...) support for passing -X stream to pg_basebackup
- src/test/example_suite/ with some simple demo tests

I found that I was writing documentation for how to write tests that'd
bitrot quickly and landed up writing a demo/sample test that can be run as
part of 'make check' with --enable-tap-tests instead. Hopefully it's not
overkill.

LMK if you think it's too much and I can trim out what's unwanted.

In the process I noticed a few helpers I think should be added to
PostgresNode. I haven't added them since I didn't want this to turn into a
big patch when it was meant to just be 'add a README', but the main things
are:

- promote (you've done this)

- Facilities to make it easier to set a master up as replication-enabled
(your patch does this, but it should use wal_level = 'logical' by default
IMO; also I think setting autovacuum=off is very wrong and will mask
problems)

- wait_for_recovery_lsn($lsn) to wait until a hot standby passes a given LSN

- wait_for_replication_lsn($lsn, $col, $appname) - wait until standby with
name $appname (or any standby, if unspecified) passes $lsn for $col, where
$col can be 'sent', 'write', 'flush' or 'replay'

> > Not committed yet, I see. That's
> https://commitfest.postgresql.org/9/438/
> > right?
>
> Yeah... That's life.
>
>
I'll comment separately on that thread.

--
Craig Ringer http://www.2ndQuadrant.com/
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