[bug#53828] [PATCH] guix: opam: Allow importing local files.

[Julien Lepiller]

On February 7, 2022 9:27:39 AM GMT+01:00, Xinglu Chen <public@yoctocell.xyz> 
wrote:
>Julien schrieb am Sonntag der 06. Februar 2022 um 22:41 +01:
>
>> Hi Guix!
>>
>> This patch lets you import opam packages from a local file. This is a
>> feature that was requested a few times, and there it is :)
>>
>> Now, if you have an OCaml package sources that provides an opam file
>> (usually called opam, or with the .opam extension), you can import the
>> package, recursively or not with something like:
>>
>> guix import opam foo -f foo.opam -r
>>
>> instead of fetching foo from the repositories, it will fetch the data
>> directly from the given file. WDYT?
>
>Why just limit it to local files?  What about accepting a tarball on the
>internet or any VCS repository?  This could generally be useful for any
>importer.

That's a good idea, but I'm not sure how to recognize these cases.

>
>Also, since we already know the name of the package, maybe specifying
>the directory that contains the OCaml project would be enough?

Sure, that could be useful for your suggestion below to use the local directory 
as the source.

>
>  guix import opam foo --type=local /path/to/directory
>  guix import opam foo --type=tarball https://example.org/foo.tar.gz
>  guix import opam foo --type=git https://git.example.org/foo
>  …
>
>Or am I asking for too much?  :-)
>
>> From b027391357eef4d6fa1bb8741528cf9650aef568 Mon Sep 17 00:00:00 2001
>> Message-Id: 
>> <b027391357eef4d6fa1bb8741528cf9650aef568.1644183523.git.julien@lepiller.eu>
>> From: Julien Lepiller <julien@lepiller.eu>
>> Date: Sun, 6 Feb 2022 22:35:14 +0100
>> Subject: [PATCH] guix: opam: Allow importing local files.
>
>It should be “import: opam: …”.
>
>> * guix/scripts/import/opam.scm (guix-import-opam): Support `--file` flag.
>> * guix/import/utils.scm (recursive-import): Add optional file argument.
>> Pass it to the first iteration when available.
>> * guix/import/opam.scm (opam-fetch): Fetch from file when available.
>> (opam->guix-source): Factorize source out of opam->guix-package.
>> (opam->guix-package): Add file argument.  Ensure it does not fail when
>> name, version and url are not available.
>> ---
>>  guix/import/opam.scm         | 101 +++++++++++++++++++----------------
>>  guix/import/utils.scm        |  17 +++---
>>  guix/scripts/import/opam.scm |  11 +++-
>>  3 files changed, 75 insertions(+), 54 deletions(-)
>>
>> diff --git a/guix/import/opam.scm b/guix/import/opam.scm
>> index a6f6fe8c9f..05f79110f8 100644
>> --- a/guix/import/opam.scm
>> +++ b/guix/import/opam.scm
>> @@ -310,8 +310,11 @@ (define (dependency-list->inputs lst)
>>    (map string->symbol
>>         (ocaml-names->guix-names lst)))
>>  
>> -(define* (opam-fetch name #:optional (repositories-specs '("opam")))
>> -  (or (fold (lambda (repository others)
>> +(define* (opam-fetch name #:optional (repositories-specs '("opam")) (file 
>> #f))
>> +  (or (and file (let ((metadata (get-metadata file)))
>> +                  `(("metadata" . ,metadata)
>> +                    ("version" . #f))))
>> +      (fold (lambda (repository others)
>>                (match (find-latest-version name repository)
>>                  ((_ version file) `(("metadata" ,@(get-metadata file))
>>                                      ("version" . ,version)))
>> @@ -320,17 +323,29 @@ (define* (opam-fetch name #:optional 
>> (repositories-specs '("opam")))
>>              (filter-map get-opam-repository repositories-specs))
>>        (warning (G_ "opam: package '~a' not found~%") name)))
>>  
>> -(define* (opam->guix-package name #:key (repo 'opam) version)
>> +(define (opam->guix-source url-dict)
>> +  (let ((source-url (and url-dict
>> +                         (or (metadata-ref url-dict "src")
>> +                             (metadata-ref url-dict "archive")))))
>> +    (if source-url
>> +        (call-with-temporary-output-file
>> +          (lambda (temp port)
>> +            (and (url-fetch source-url temp)
>> +                 `(origin
>> +                    (method url-fetch)
>> +                    (uri ,source-url)
>> +                    (sha256 (base32 ,(guix-hash-url temp)))))))
>> +        'no-source-information)))
>
>I would use ‘and-let*’ instead of ‘let’, and drop the ‘if’ form.

That would return #f and make the ocher and-let* in opam->guix-package fail.

>
>The ability to import from a local file seems to mostly be useful when
>the package isn’t meant to be submitted to Guix, right?  Wouldn’t it
>make more sense to make the source a ‘local-file’ object instead of just
>setting it to #f?

Excellent idea.

>
>> +(define* (opam->guix-package name #:key (repo '("opam")) (file #f) version)
>>    "Import OPAM package NAME from REPOSITORY (a directory name) or, if
>> -REPOSITORY is #f, from the official OPAM repository.  Return a 'package' 
>> sexp
>> +REPOSITORY is #f, from the official OPAM repository.  When FILE is defined,
>> +import the packaged defined in the opam FILE instead.  Return a 'package' 
>> sexp
>
>s/packaged/package/
>
>>    (and-let* ((with-opam (if (member "opam" repo) repo (cons "opam" repo)))
>> -             (opam-file (opam-fetch name with-opam))
>> -             (version (assoc-ref opam-file "version"))
>> +             (opam-file (opam-fetch name with-opam file))
>>               (opam-content (assoc-ref opam-file "metadata"))
>> -             (url-dict (metadata-ref opam-content "url"))
>> -             (source-url (or (metadata-ref url-dict "src")
>> -                             (metadata-ref url-dict "archive")))
>> +             (source (opam->guix-source (metadata-ref opam-content "url")))
>>               (requirements (metadata-ref opam-content "depends"))
>>               (names (dependency-list->names requirements))
>>               (dependencies (filter-dependencies names))
>> @@ -344,47 +359,41 @@ (define* (opam->guix-package name #:key (repo 'opam) 
>> version)
>>                                    (not (member name '("dune" "jbuilder"))))
>>                                  native-dependencies))))
>>          (let ((use-dune? (member "dune" names)))
>> -          (call-with-temporary-output-file
>> -            (lambda (temp port)
>> -              (and (url-fetch source-url temp)
>> -                   (values
>> -                    `(package
>> -                       (name ,(ocaml-name->guix-name name))
>> -                       (version ,version)
>> -                       (source
>> -                         (origin
>> -                           (method url-fetch)
>> -                           (uri ,source-url)
>> -                           (sha256 (base32 ,(guix-hash-url temp)))))
>> -                       (build-system ,(if use-dune?
>> -                                          'dune-build-system
>> -                                          'ocaml-build-system))
>> -                       ,@(if (null? inputs)
>> -                           '()
>> -                           `((propagated-inputs (list ,@inputs))))
>> -                       ,@(if (null? native-inputs)
>> -                           '()
>> -                           `((native-inputs (list ,@native-inputs))))
>> -                       ,@(if (equal? name (guix-name->opam-name 
>> (ocaml-name->guix-name name)))
>> -                           '()
>> -                           `((properties
>> -                               ,(list 'quasiquote `((upstream-name . 
>> ,name))))))
>> -                       (home-page ,(metadata-ref opam-content "homepage"))
>> -                       (synopsis ,(metadata-ref opam-content "synopsis"))
>> -                       (description ,(beautify-description
>> -                                      (metadata-ref opam-content 
>> "description")))
>> -                       (license ,(spdx-string->license
>> -                                  (metadata-ref opam-content "license"))))
>> -                    (filter
>> -                      (lambda (name)
>> -                        (not (member name '("dune" "jbuilder"))))
>> -                      dependencies))))))))
>> +          (values
>> +           `(package
>> +              (name ,(and name (ocaml-name->guix-name name)))
>> +              (version ,(assoc-ref opam-file "version"))
>> +              (source ,source)
>> +              (build-system ,(if use-dune?
>> +                                 'dune-build-system
>> +                                 'ocaml-build-system))
>> +              ,@(if (null? inputs)
>> +                  '()
>> +                  `((propagated-inputs (list ,@inputs))))
>> +              ,@(if (null? native-inputs)
>> +                  '()
>> +                  `((native-inputs (list ,@native-inputs))))
>> +              ,@(if (and name (equal? name (guix-name->opam-name 
>> (ocaml-name->guix-name name))))
>> +                  '()
>> +                  `((properties
>> +                      ,(list 'quasiquote `((upstream-name . ,name))))))
>> +              (home-page ,(metadata-ref opam-content "homepage"))
>> +              (synopsis ,(metadata-ref opam-content "synopsis"))
>> +              (description ,(beautify-description
>> +                             (metadata-ref opam-content "description")))
>> +              (license ,(spdx-string->license
>> +                         (metadata-ref opam-content "license"))))
>> +           (filter
>> +             (lambda (name)
>> +               (not (member name '("dune" "jbuilder"))))
>> +             dependencies)))))
>>  
>> -(define* (opam-recursive-import package-name #:key repo)
>> +(define* (opam-recursive-import package-name #:key repo file)
>>    (recursive-import package-name
>>                      #:repo->guix-package opam->guix-package
>>                      #:guix-name ocaml-name->guix-name
>> -                    #:repo repo))
>> +                    #:repo repo
>> +                    #:file file))
>>  
>>  (define (guix-name->opam-name name)
>>    (if (string-prefix? "ocaml-" name)
>> diff --git a/guix/import/utils.scm b/guix/import/utils.scm
>> index 1c3cfa3e0b..ab35b8a4fc 100644
>> --- a/guix/import/utils.scm
>> +++ b/guix/import/utils.scm
>> @@ -470,7 +470,7 @@ (define (topological-sort nodes
>>                     (set-insert (node-name head) visited))))))))
>>  
>>  (define* (recursive-import package-name
>> -                           #:key repo->guix-package guix-name version repo
>> +                           #:key repo->guix-package guix-name version repo 
>> file
>>                             #:allow-other-keys)
>>    "Return a list of package expressions for PACKAGE-NAME and all its
>>  dependencies, sorted in topological order.  For each package,
>
>The docstrings should also be updated.