Re: System username in pg_stat_activity

On Fri, Jan 19, 2024 at 7:20 AM Bertrand Drouvot
<bertranddrouvot(dot)pg(at)gmail(dot)com> wrote:
>
> Hi,
>
> On Thu, Jan 18, 2024 at 04:01:33PM +0100, Magnus Hagander wrote:
> > On Mon, Jan 15, 2024 at 11:17 AM Bertrand Drouvot
> > > Did you forget to share the new revision (aka v4)? I can only see the
> > > "reorder_parallel_worker_bestart.patch" attached.
> >
> > I did. Here it is, and also including that suggested docs fix as well
> > as a rebase on current master.
> >
>
> Thanks!
>
> Just a few comments:
>
> 1 ===
>
> + The authentication method used for authenticating the connection, or
> + NULL for background processes.
>
> What about? "NULL for background processes (except for parallel workers which
> inherit this information from their leader process)"

Ugh. That doesn't read very well at all to me. Maybe just "NULL for
background processes without a user"?

> 2 ===
>
> + cycle before they were assigned a database role. Contains the same
> + value as the identity part in <xref linkend="system-user" />, or NULL
> + for background processes.
>
> Same comment about parallel workers.
>
> 3 ===
>
> +# pg_stat_activity should contain trust and empty string for trust auth
> +$res = $node->safe_psql(
> + 'postgres',
> + "SELECT auth_method, auth_identity='' FROM pg_stat_activity WHERE pid=pg_backend_pid()",
> + connstr => "user=scram_role");
> +is($res, 'trust|t', 'Users with trust authentication should show correctly in pg_stat_activity');
> +
> +# pg_stat_activity should contain NULL for auth of background processes
> +# (test is a bit out of place here, but this is where the other pg_stat_activity.auth* tests are)
> +$res = $node->safe_psql(
> + 'postgres',
> + "SELECT auth_method IS NULL, auth_identity IS NULL FROM pg_stat_activity WHERE backend_type='checkpointer'",
> +);
> +is($res, 't|t', 'Background processes should show NULL for auth in pg_stat_activity');
>
> What do you think about testing the parallel workers cases too? (I'm not 100%
> sure it's worth the extra complexity though).

I'm leaning towards not worth that.

--
Magnus Hagander
Me: https://www.hagander.net/
Work: https://www.redpill-linpro.com/