Re: how to "guix pack" a profile?

[zimoun]

Dear,

On Thu, 18 Jun 2020 at 18:20, elaexuotee@wilsonb.com wrote:

> By `profile', I mean any store output named like /gnu/store/<hash>-profile.
> These outputs are created by `guix package' invocations as well as `guix
> environment' ones.
>
> By `user profile', I mean the (non-static) contents pointed to by
> ~/.guix-profile. These contents get updated on `guix package' invocations (by
> updating the ~/.guix-profile symlink).

Well, from my understanding, any profile point to /gnu/store/<hash>-profile.

--8<---------------cut here---------------start------------->8---
$ readlink -f ~/.guix-profile
/gnu/store/192k3kck2w3g2ms43dry41la9lwrqf37-profile

$ guix package -i hello -p /tmp/hello
$ readlink -f /tmp/hello
/gnu/store/p196x4m6ix33mgsbfacvqaw60129pndw-profile
--8<---------------cut here---------------end--------------->8---


> Using this terminology, we both agree than managing your `user profile' via
> "manifest.scm" (and "channels.scm") is the way to go. Those two files provide 
> a
> specification which guix *resolves* into a concrete `profile'.
>
> The imminently practical issue that you, Ludo, and Pierre seem to be working 
> on
> is a way of easing the transition from imperative to declarative `user 
> profile'
> management.
>
> In contrast, I am proposing making `profiles' first class. By this I mean a
> file under /gnu/store/<hash>-profile that contains the code capable of
> completely and deterministically rebuilding that exact profile, and that
> profile *only*.

For which use case?

Well, let say there is a profile which could be a mess and I only see
two usages currently uncovered:

 1. create an environment based on this profile; either to temporarily
   extend it (which is AFAIK already more or less covered), either to
   isolate it,
 2. pack it for sharing with your colleague.


> Just for the sake of argument, let's call this file "recipe.scm", and let's
> choose a profile, /gnu/store/123abc-profile. Then the following should be 
> true:
>
>     $ guix package --manifest /gnu/store/123abc-profile/recipe.scm
>     $ readlink -f ~/guix-profile
>     /gnu/store/123abc-profile
>
> I.e. that `guix package' invocation would have the effect of setting the
> current user generation to that exact profile.
>
> Of course, if we had such a "recipe.scm" then the following would Just Work:
>
>     # Containerize a profile.
>     $ guix pack --manifest /gnu/store/123abc-profile/recipe.scm
>
>     # Share profiles with your Guix friends.
>     $ guix environment --manifest ~/downloads/friends-awesome-profile.scm
>
> And it plays well with potential future features:
>
>     # Copy whole profiles between Guix stores
>     $ guix archive --manifest /gnu/store/123abc-profile/recipe.scm
>
> Hopefully my generalized idea is clearer now.

What you describe here is exactly what Pierre and other have proposed.
And the work-to-do is to prototype the format of what you called
"recipe.scm", which means equivalently in the previous emails change the
format of <profile>/manifest.


All the best,
simon