Extend channel-build-system?

Extend channel-build-system?

[Nicolas Graves]

Hi Guix,

I am struggling to build a channel with properly defined metadata and/or
proper dependencies.  This is because the current channel-builds-system
is only able to build a guix channel, rather than any channel.

Also, the error reporting is not great when trying to build another channel:
```
ice-9/boot-9.scm:1685:16: In procedure raise-exception:
In procedure struct-vtable: Wrong type argument in position 1 (expecting struct): #f
```

IIUC, this is because in `channel-instance-derivations` needs a
`core-instance`.  In the context of another channel than guix, it could
be extracted either from channel metadata dependencies or from inputs.

WDYT?  Do you already know of a way to do this?

-- 
Best regards,
Nicolas Graves

Re: Extend channel-build-system?

[Suhail Singh]

Nicolas Graves <ngraves@ngraves.fr> writes:

> This is because the current channel-builds-system is only able to
> build a guix channel, rather than any channel.

Perhaps this is obvious to others, but for the benefit of others (such
as myself), could you please share some specifics?

-- 
Suhail

Re: Extend channel-build-system?

[Nicolas Graves]

On 2025-01-06 21:18, Suhail Singh wrote:

> Nicolas Graves <ngraves@ngraves.fr> writes:
>
>> This is because the current channel-builds-system is only able to
>> build a guix channel, rather than any channel.
>
> Perhaps this is obvious to others, but for the benefit of others (such
> as myself), could you please share some specifics?

Some docstrings state that directly (despite the rather unituitive
channel-build-system != guix-channel-build-system).  But I basically
discovered that through error digging.

For instance in the manual :
The resulting package is a Guix instance of the given channel(s), similar
to how @command{guix time-machine} would build it.

For RDE, I'm trying to get that built with a guile-build-system which is
quite close to what I wanted actually.  I'm at peace without an
extension of the build-system, but we should probably at least make it
more visible in the manual and doctrings that this is only for a Guix
channel and cannot be user to build any channel you found online.

-- 
Best regards,
Nicolas Graves

Re: Extend channel-build-system?

[Suhail Singh]

Nicolas Graves <ngraves@ngraves.fr> writes:

> I'm at peace without an extension of the build-system, but we should
> probably at least make it more visible in the manual and doctrings
> that this is only for a Guix channel and cannot be user to build any
> channel you found online.

I probably would've wasted some time chasing some dead-ends if I were in
your shoes as well.  If not an extension of the build system, I propose
that we make this a little more explicit in the manual.  As well, a
small example in the Cookbook may not be a bad idea either.

While I don't have commit access, I'd be happy to review the patch(es)
as needed.

-- 
Suhail

Re: Extend channel-build-system?

[Ludovic Courtès]

Hi Nicolas,

Nicolas Graves <ngraves@ngraves.fr> skribis:

> I am struggling to build a channel with properly defined metadata and/or
> proper dependencies.  This is because the current channel-builds-system
> is only able to build a guix channel, rather than any channel.

AFAICS, ‘channel-build-system’ requires at least the ‘guix’ channel, but
it can also be passed additional channels via #:channels.

Did that not work for you?  How did you get the error you mentioned?

As always, one cannot just build one channel: you always have to have
the ‘guix’ channel together with the other channels you care about.

HTH,
Ludo’.