[bug#46031] services: cuirass: Add "simple-cuirass-services".

["Ludovic Courtès" <ludo@gnu.org>]

Hello,

Mathieu Othacehe <othacehe@gnu.org> skribis:

>> So, if postgresql-role-service-type and postgresql-service-type have a
>> default value, simple-cuirass-service could extend them both (possibly
>> with a dummy value) and it would just work.
>
> With 8163f74542300720f6ee5dc061b79ddf0c345bb8 and
> 108e2c6116f01c3b0a98498717d65a96c1857a51, I made sure that those
> services are automatically instantiated when missing.
>
> This means simple-cuirass-configuration->specs makes way more sense, as
> you suggested. Took care of it with
> bebcf97600b2fa65482ae8ee870800dafa34d3f8.

Yay!

> Now, as suggested by Jonathan on IRC yesterday, it would be nice to
> be able to build only the packages of a given channel. For that, we
> would need to be able to figure out which channel is providing a
> package, with something like a package-channel field.
>
> Do you think that would make sense?

One could filter packages from the manifest.

Currently there’s no definite way to know which channel a given package
comes from.  ‘package-provenance’ in (guix describe) approximates that.
Perhaps we should try something along these lines.

I guess the first step would be to provide an a ‘package-channel(s)’
procedure that does like ‘package-provenance’, but returns a list of
channels.

WDYT?

Ludo’.