Re: GSoC-2018 - Build daemon rewrite in Scheme Updates

[Ludovic Courtès]

Hello uniq10,

Thanks for the update!

Sandeep Subramanian <address@hidden> skribis:

> `build-derivation` is now using `call-with-container`
> and it seems to work well. `build-derivation` assumes
> that all the inputs needed for the derivation is already
> built and ready. As a next step I wanted to try and build
> the `inputDrvs` if the inputs are missing.

Nice, it sounds like a good start.

Where is the code you’ve been working on?  Is it
<https://github.com/uniq10/guix/tree/guile-daemon-merged>?

In general, I would encourage you to follow the project’s conventions as
closely as possible to ease future merges.  See
<https://www.gnu.org/software/guix/manual/html_node/Contributing.html>.
Please also consider showing up on #guix on IRC to share what you’re up
to and ask for advice whenever you feel like it.  Communication is key
is a distributed project like this.

As discussed off-list, I just started merging into ‘master’ proper work
from last year: <https://bugs.gnu.org/31618>.  This is an area where
we’ll obviously have to coordinate.  For example it’d be great if you
could rebase onto master once 31618 has been merged, and let me know if
anything is amiss.

> I looked through the C++ code to find out how exactly
> this is done and I have a good understanding of it now.
> I plan to emulate the behaviour of the C++ code for
> the entire derivation building pipeline.
>
> I spent a lot of time browsing the C++ code base and had
> to keep going back to it often, since I had trouble keeping
> the C++ code flow in memory. So, I thought it would be
> worthwhile to write some detailed notes on the C++ daemon
> code base that I can refer to while coding. The notes I made
> can be found here:
> https://github.com/uniq10/gsoc-guix-notes/blob/master/daemon-notes.md

Woow, very nice!  From a quick look it does seem to correctly reflect
what’s happening in that code.  It would have helped me a lot to have
such a document back then.  ;-)

BTW, note that you shouldn’t take the structure of the C++ code as a
reference to follow.  In Scheme we would more naturally use different
idioms than those of this code (object-oriented C++).  You’re welcome to
discuss on this list or on IRC how to structure things.

Thanks for the update and for the nice work!

Ludo’.