Re: (almost) deterministic patchsets

[Nicolas Graves]

This is basically done in
https://git.sr.ht/~ngraves/dotfiles/commit/bd542512dfad2beccb4a6cdb2468f79aa869a55b

Maybe some things need some polish, but the PoC is definitely here.
Feel free to reuse this in upstream guix if you want.

On 2024-02-13 14:35, Nicolas Graves wrote:

> Hi !
>
> I've written this (gpl3+) that should be able to fetch patchsets for
> both guix and rde. This should be robust enough for guix/rde use IMO.
>
> (define-module (guix mbox-download)
>   #:use-module (guix packages)
>   #:use-module ((guix self) #:select (make-config.scm))
>   #:use-module (guix modules)
>   #:use-module (guix monads)
>   #:use-module (gnu packages guile)
>   #:use-module (gnu packages tls)
>   #:use-module (gnu packages version-control)
>   #:use-module (guix store)
>   #:use-module (guix gexp)
>   #:use-module (guix records)
>   #:export (mbox-fetch
>             mbox-reference))
>
> (define-record-type* <mbox-reference>
>   mbox-reference make-mbox-reference
>   mbox-reference?
>   (type mbox-reference-type)
>   (id mbox-reference-id)
>   (version mbox-reference-version))
>
> (define* (mbox-fetch ref hash-algo hash #:optional name
>                      #:key (system %current-system) guile)
>
>   (define uri
>     (format
>      #f
>      (assoc-ref
>       '((gnu . 
> "https://debbugs.gnu.org/cgi-bin/bugreport.cgi?bug=~a;mbox=yes";)
>         (rde . "https://lists.sr.ht/~~abcdw/rde-devel/patches/~a/mbox";))
>        (mbox-reference-type ref))
>      (mbox-reference-id ref)))
>
>   (define modules
>     (cons `((guix config) => ,(make-config.scm))
>           (delete '(guix config)
>                   (source-module-closure '((guix build download)
>                                            (guix build utils))))))
>
>   (define build
>     (with-extensions (list guile-json-4 guile-gnutls)
>       (with-imported-modules modules
>         #~(begin
>             (use-modules (guix build utils) (guix build download))
>             (let ((mbox #$(match-record ref <mbox-reference>
>                                         (type id version)
>                             (format #f "~a-~a-~a.mbx" type id version))))
>               (setenv "TMPDIR" (getcwd))
>               (setenv "XDG_DATA_HOME" (getcwd))
>               (invoke #$(file-append b4 "/bin/b4")
>                       "-d" "-n" "--offline-mode" "--no-stdin"
>                       "am" "--no-cover" "--no-cache"
>                       "--use-local-mbox"
>                       (url-fetch #$uri "mbox" #:verify-certificate? #f)
>                       "--use-version"
>                       (number->string #$(mbox-reference-version ref))
>                       "--no-add-trailers"
>                       "--outdir" "."
>                       "--mbox-name" mbox)
>               (install-file mbox #$output))))))
>
>   (mlet %store-monad ((guile (package->derivation (or guile (default-guile))
>                                                   system)))
>     (gexp->derivation (or name
>                           (match-record ref <mbox-reference>
>                                         (type id version)
>                             (format #f "~a-~a-~a-mbox" type id version)))
>       build
>       ;; Use environment variables and a fixed script name so
>       ;; there's only one script in store for all the
>       ;; downloads.
>       #:system system
>       #:local-build? #t ;don't offload repo cloning
>       #:hash-algo hash-algo
>       #:hash hash
>       #:recursive? #t
>       #:guile-for-build guile)))
>
>
> This can be used in such an example :
>
> (use-modules (guix mbox-download) (guix packages) (guix gexp)
>              (guix monads) (guix store) (guix derivations))
>
> (with-store store
>   (run-with-store store
>     (mlet* %store-monad
>         ((drv (origin->derivation
>                (pk 'o (origin
>                         (method mbox-fetch)
>                         (uri (mbox-reference
>                               (type 'rde)
>                               (id 44893)
>                               (version 4)))
>                         (sha256
>                          (base32 
> "1rs09wxvdaxrk2zh6g23s9min76wjm9lw0a5pjklc7cfraasi7s9")))))))
>       (return drv))))
>
> Is guix interested in this, should I send a patch? What about renaming
> this to patchset-reference instead of mbox-reference?
>
> My end-goal here is to use this to extend channels to channels with
> patches, with something like this :
>
> (define* (instantiate-channel ch)
>   (match ch
>     ((name url ref patches)
>      (primitive-eval
>       `(channel
>         (name ',name)
>         ,@(if (null? patches)
>               `((url ,(find-home url)))
>               `((url ,(patched-source
>                (symbol->string name)
>                (git-checkout
>                 (url (find-home url))
>                 (commit ref))
>                (search-patches patches)))))
>         ,@(if ((@ (guix git) commit-id?) ref)
>               `((commit ,ref))
>               `((branch ,ref)))
>         (introduction ,(assoc-ref channels-introductions name)))))))
>
> in the hypothesis where patched-source is exported from (guix 
> transformations).

--
Best regards,
Nicolas Graves