Re: Using gitlab-ci to maintain a channel?

["Ludovic Courtès" <ludo@gnu.org>]

Hi Hartmut!

Hartmut Goebel <h.goebel@crazy-compilers.com> skribis:

> I wonder whether it's possible to maintain a channel using gitlab-ci. Any thought or experiences to share?

[...]

> * What version of guix shall be used? Always the latest one?

That’s the main conceptual issue: GitLab-CI only knows about the repo
it’s tracking, it doesn’t realize that whether the code therein builds
fine depends on the ‘guix’ channel.

To get that level of precision, you would need Cuirass, which is what we
use at work and for various scientific channels:
<https://guix.bordeaux.inria.fr>.

Now, GitLab integration is appealing, so it would still be nice to do CI
with a fixed revision of Guix, which you would occasionally manually
update.  It’s a tradeoff.

> * The runners need a docker image. Where to I get one? Possibly containing a warmed-up cache? (Using a Debian docker image and
>  installing guix into it on every run sounds like a bad idea.)

As I mentioned on help-guix a few days (weeks?) ago, I haven’t found a
way to build such an image with Guix, but I’d like to find one!

Another option is to use, say, Debian as the base image, and to install
Guix on top of it.

> * OTOH /gnu/tore could be cached. How much data would this typically be?
> * How to clean the cache from unreachable items?
> * How to publish the substitutes?

I don’t think you could publish substitutes in that setup, unless
GitLab-CI offload builds to an actual machine that has ‘guix publish’
running on it.

HTH,
Ludo’.