Unable to determine system origin when configuration stored in guix channel

Hi,

I recently converted my guix configuration to be stored in a channel, primarily to allow me to reference files in the repository but yet still have a self-contained configuration. It also allows me to easily build packages and images from my local guix instance. I also like how the specification of my system (or home) is precisely defined by a set of channels, and an expression which evaluates to the operating-system (or home-configuration) that I'm deploying.

As per the guix manual:

This all being said, I noticed an issue in that I'm unable to determine the provenance of a system when my configuration is stored in a guix channel.

Specifically, if I have a guix channel that contains two modules, each of which exports a %system variable of type operating-system, I cannot tell which one was used to instantiate the system. This is due to two issues. The first is because when `-e|--expression` arguments are used, `configuration-file` is set to `#f` in the generations provenance file but the expression itself is not stored in the provenance file, and is not listed in `guix system describe`, `guix system list-generations`, etc.. commands.

Change the system to 'system-b':

Notice how there is no way to see which configuration was used to create the system.

The second issue is that when `-L|--load-path` is used along with either a file or expression to specify the operating-system or home-configuration, it essentially 'tarnishes' the provenance of the system, in that the following deployment is not differentiable from the preceding one/s, despite them being different.

Thank you for reading

--

Collin J. Doering

Am Dienstag, dem 29.03.2022 um 22:03 -0400 schrieb Collin J. Doering:

The key here is that you're using a configuration expression rather

than a file. Were you to write those files to disk in let's say

config-a.scm and config-b.scm respectively and refer to them on the

command line like that, you'd have a configuration file guix could

refer to.

Alternatively, Guix could take the expression specified via -e and

write it to disk. Note that some configuration files are meaningless

even if written to disk, for example...

LOAD_PATH tweaking should be considered harmful and void your

provenance, at least w.r.t. channels. There's no sane way for guix to

check whether the load paths you added still exist after

reconfiguration, other than placing the entire directory in the store.

Cheers

Hi Liliana,

Thank you for your response :)

I think this would be the best way to resolve this issue. Also, thanks for your explanation.

I agree! However, I think it would be nice if `guix system describe`, `guix system list-generations`, `guix home list-generations`, etc.. indicated when a generation was created with the `-L|--load-path` argument specified. As you said, it 'voids you provenance', so I think its something that should be visually indicated to the user.

Regards

--

Collin J. Doering