bug#26608: bug#22629: “Stable” branch

[ludo@gnu.org (Ludovic Courtès)]

Hi Alex,

Alex Sassmannshausen <alex@pompo.co> skribis:

> So the example you provided is a user-defined policy to install the
> latest version of Guix that is downloadable using substitutes (if guix
> publish has published those already).
>
> As you say, in a similar vein, the end user could for themselves define
> a policy that searches for a commit containing a specific successful
> build, or a set of specific successful builds.

Exactly.

>> As I imagine it, the cost would be a few HTTP queries to the Cuirass
>> API.  I should try to come up with an example to better explain what I
>> had in mind!
>
> Your example helps visualize this, thanks.
>
> Your example depends on there being a jobset that comprises the set of
> packages you are interested in testing.

Yes, and it’s hacky in that the substitute server and jobset names are
hard-coded, but you get the idea.

> I imagine it is possible to do the same for an individual package / job.

Yes.

> The situation would be different if the end user wanted to perform a
> similar operation for an arbitrary set of packages on their end.

It would be quite similar: you would query the set of builds of an
evaluation of the “guix-modular” jobset and check whether the packages
of interest were built.

>> What I typically do is “guix pull && guix package -n -u”.  Then I look
>> at things that would be built; if, say, LibreOffice is among them, I
>> wait for a little while and try again later, until I can get enough
>> substitutes.  That usually works okay, but it fails if it turns out that
>> one of the dependencies fails to build: substitutes never become
>> available in that case.
>
> Interesting.  Do you think this kind of thing might be useful to have in
> the Guix manual? Like, in a section about a "typical" desktop end-user
> might manage their system day to day?

It would make sense to have such a section I guess.  However, before
teaching users how to work around deficiencies of our infrastructure our
processes ;-), I’d like us to improve them much as possible.  I’m sure
we have room for improvement for instance in Cuirass.

Thanks,
Ludo’.