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+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2023 Pierre-Henry Fröhring <contact@phfrohring.com>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
+
+;; Commentary:
+;;
+;; Standard build procedure for Elixir packages using 'mix'. This is
+;; implemented as an extension of 'gnu-build-system'.
+;;
+;; Code:
+
+(define-module (guix build-system mix)
+ #:use-module (guix build mix-build-system)
+ #:use-module (guix build-system gnu)
+ #:use-module (guix build-system)
+ #:use-module (guix gexp)
+ #:use-module (guix monads)
+ #:use-module (guix packages)
+ #:use-module (guix search-paths)
+ #:use-module (guix store)
+ #:use-module (guix utils)
+ #:use-module (ice-9 match)
+ #:use-module (srfi srfi-1)
+ #:use-module (srfi srfi-26)
+ #:export (mix-build-system hexpm-uri))
+
+;; Lazily resolve bindings to avoid circular dependencies.
+(define (default-glibc-utf8-locales)
+ (let* ((base (resolve-interface '(gnu packages base))))
+ (module-ref base 'glibc-utf8-locales)))
+
+(define (default-elixir-hex)
+ (let ((elixir (resolve-interface '(gnu packages elixir))))
+ (module-ref elixir 'elixir-hex)))
+
+(define (default-rebar3)
+ (let ((erlang (resolve-interface '(gnu packages erlang))))
+ (module-ref erlang 'rebar3)))
+
+(define (default-elixir)
+ (let ((elixir (resolve-interface '(gnu packages elixir))))
+ (module-ref elixir 'elixir)))
+
+(define* (strip-prefix name #:optional (prefix "elixir-"))
+ "Return NAME without the prefix PREFIX."
+ (if (string-prefix? prefix name)
+ (string-drop name (string-length prefix))
+ name))
+
+(define (hexpm-uri name version)
+ "Return the URI where to fetch the sources of a Hex package NAME at VERSION.
+NAME is the name of the package which should look like: elixir-pkg-name-X.Y.Z
+See: https://github.com/hexpm/specifications/blob/main/endpoints.md"
+ ((compose
+ (cute string-append "https://repo.hex.pm/tarballs/" <> "-" version ".tar")
+ (cute string-replace-substring <> "-" "_")
+ strip-prefix)
+ name))
+
+;; A number of environment variables specific to the Mix build system are
+;; reflected here. They are documented at
+;; https://hexdocs.pm/mix/1.15.7/Mix.html#module-environment-variables. Other
+;; parameters located in mix.exs are defined at
+;; https://hexdocs.pm/mix/1.15.7/Mix.Project.html#module-configuration
+(define* (mix-build name
+ inputs
+ #:key
+ source
+ (tests? #t)
+ (mix-path #f) ;See MIX_PATH.
+ (mix-exs "mix.exs") ;See MIX_EXS.
+ (build-per-environment #t) ;See :build_per_environment.
+ (phases '%standard-phases)
+ (outputs '("out"))
+ (search-paths '())
+ (system (%current-system))
+ (guile #f)
+ (imported-modules `((guix build mix-build-system)
+ ,@%gnu-build-system-modules))
+ (modules '((guix build mix-build-system)
+ (guix build utils))))
+ "Build SOURCE using Elixir, and with INPUTS."
+
+ ;; Check the documentation of :build_per_environment here:
+ ;; https://hexdocs.pm/mix/1.15.7/Mix.Project.html#module-configuration And
+ ;; "Environments" here:
+ ;; https://hexdocs.pm/mix/1.15.7/Mix.html#module-environments
+ (define mix-environments
+ (if build-per-environment
+ `("prod" ,@(if tests? '("test") '()))
+ '("shared")))
+
+ (define builder
+ (with-imported-modules imported-modules
+ #~(begin
+
+ (use-modules #$@(sexp->gexp modules))
+
+ #$(with-build-variables inputs outputs
+ #~(mix-build #:name #$name
+ #:source #+source
+ #:system #$system
+ #:tests? #$tests?
+ #:mix-path #$mix-path
+ #:mix-exs #$mix-exs
+ #:mix-environments '#$mix-environments
+ #:build-per-environment #$build-per-environment
+ #:phases #$(if (pair? phases)
+ (sexp->gexp phases)
+ phases)
+ #:outputs %outputs
+ #:search-paths '#$(sexp->gexp
+ (map
+ search-path-specification->sexp
+ search-paths))
+ #:inputs
+ %build-inputs)))))
+
+ (mlet %store-monad ((guile (package->derivation (or guile (default-guile))
+ system
+ #:graft? #f)))
+ (gexp->derivation name
+ builder
+ #:system system
+ #:graft? #f ;consistent with 'gnu-build'
+ #:target #f
+ #:guile-for-build guile)))
+
+(define* (lower name
+ #:key
+ (elixir (default-elixir))
+ (elixir-hex (default-elixir-hex))
+ (glibc-utf8-locales (default-glibc-utf8-locales))
+ (inputs '())
+ (native-inputs '())
+ (propagated-inputs '())
+ (rebar3 (default-rebar3))
+ (tests? #t)
+ outputs
+ source
+ system
+ target
+ #:allow-other-keys #:rest arguments)
+ "Return a bag for NAME."
+ (let ((private-keywords
+ '(#:inputs #:native-inputs
+ #:outputs #:system #:target
+ #:elixir #:elixir-hex #:glibc-utf8-locales
+ #:rebar3 #:erlang))
+ (build-inputs
+ `(,@(standard-packages)
+ ("glibc-utf8-locales" ,glibc-utf8-locales)
+ ("erlang" ,(lookup-package-input elixir "erlang"))
+ ("rebar3" ,rebar3)
+ ("elixir" ,elixir)
+ ("elixir-hex" ,elixir-hex)
+ ,@inputs
+ ,@native-inputs)))
+ (bag (name name)
+ (system system)
+ (build-inputs build-inputs)
+ (host-inputs (if target inputs '()))
+ (outputs outputs)
+ (build mix-build)
+ (arguments (strip-keyword-arguments private-keywords arguments)))))
+
+(define mix-build-system
+ (build-system (name 'mix)
+ (description "The standard Mix build system")
+ (lower lower)))
+
+;;; mix.scm ends here
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+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2023 Pierre-Henry Fröhring <contact@phfrohring.com>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
+
+;; Commentary:
+;;
+;; Code:
+
+(define-module (guix build mix-build-system)
+ #:use-module ((guix build gnu-build-system) #:prefix gnu:)
+ #:use-module (guix build utils)
+ #:use-module (ice-9 ftw)
+ #:use-module (ice-9 match)
+ #:use-module (ice-9 regex)
+ #:use-module (ice-9 string-fun)
+ #:use-module (srfi srfi-1)
+ #:use-module (srfi srfi-26)
+ #:use-module (srfi srfi-71)
+ #:export (mix-build
+ %standard-phases))
+
+;; The Elixir version is constant as soon as it is computable from the current
+;; execution. It is a X.Y string where X and Y are respectively the major and
+;; minor version number of the Elixir used in the build.
+(define %elixir-version (make-parameter "X.Y"))
+
+(define* (elixir-libdir path #:optional (version (%elixir-version)))
+ "Return the path where all libraries under PATH for a specified Elixir
+VERSION are installed."
+ (string-append path "/lib/elixir/" version))
+
+(define* (strip-prefix name #:optional (prefix "elixir-"))
+ "Return NAME without the prefix PREFIX."
+ (if (string-prefix? prefix name)
+ (string-drop name (string-length prefix))
+ name))
+
+(define (mix-build-dir mix-build-root mix-env)
+ "Return the directory where build artifacts are to be installed according to
+en environment MIX-ENV in the current directory. MIX-BUILD-ROOT depends on the
+package arguments. See: https://hexdocs.pm/mix/1.15/Mix.html#module-environment-variables"
+ (string-append mix-build-root "/" mix-env "/lib"))
+
+(define (elixir-version inputs)
+ "Return an X.Y string where X and Y are respectively the major and minor version number of PACKAGE.
+Example: /gnu/store/…-elixir-1.14.0 → 1.14"
+ ((compose
+ (cute string-join <> ".")
+ (cute take <> 2)
+ (cute string-split <> #\.)
+ strip-prefix
+ strip-store-file-name)
+ (assoc-ref inputs "elixir")))
+
+(define* (unpack #:key source mix-path #:allow-other-keys)
+ "Unpack SOURCE in the working directory, and change directory within the
+source. When SOURCE is a directory, copy it in a sub-directory of the current
+working directory."
+ (let ((gnu-unpack (assoc-ref gnu:%standard-phases 'unpack)))
+ (gnu-unpack #:source source)
+ (when (file-exists? "contents.tar.gz")
+ (invoke "tar" "xvf" "contents.tar.gz"))))
+
+(define (list-directories dir)
+ "List absolute paths of directories directly under the directory DIR."
+ (map (cute string-append dir "/" <>)
+ (scandir dir (lambda (filename)
+ (and (not (member filename '("." "..")))
+ (directory-exists? (string-append dir "/" filename)))))))
+
+(define* (set-mix-env #:key inputs mix-path mix-exs #:allow-other-keys)
+ "Set environment variables.
+See: https://hexdocs.pm/mix/1.15.7/Mix.html#module-environment-variables"
+ (setenv "MIX_ARCHIVES" "archives")
+ (setenv "MIX_BUILD_ROOT" "_build")
+ (setenv "MIX_DEPS_PATH" "deps")
+ (setenv "MIX_EXS" mix-exs)
+ (setenv "MIX_HOME" (getcwd))
+ (setenv "MIX_PATH" (or mix-path ""))
+ (setenv "MIX_REBAR3" (string-append (assoc-ref inputs "rebar3") "/bin/rebar3")))
+
+(define* (set-elixir-version #:key inputs #:allow-other-keys)
+ "Store the version number of the Elixir input in a parameter."
+ (%elixir-version (elixir-version inputs))
+ (format #t "Elixir version: ~a~%" (%elixir-version)))
+
+(define* (build #:key mix-environments #:allow-other-keys)
+ "Builds the Mix project."
+ (for-each (lambda (mix-env)
+ (setenv "MIX_ENV" mix-env)
+ (invoke "mix" "compile" "--no-deps-check"))
+ mix-environments))
+
+(define* (check #:key (tests? #t) #:allow-other-keys)
+ "Test the Mix project."
+ (if tests?
+ (invoke "mix" "test" "--no-deps-check")
+ (format #t "tests? = ~a~%" tests?)))
+
+(define* (remove-mix-dirs . _)
+ "Remove all .mix/ directories.
+We do not want to copy them to the installation directory."
+ (for-each delete-file-recursively
+ (find-files "." (file-name-predicate "\\.mix$") #:directories? #t)))
+
+(define (package-name->elixir-name name+ver)
+ "Convert the Guix package NAME-VER to the corresponding Elixir name-version
+format. Example: elixir-a-pkg-1.2.3 -> a_pkg"
+ ((compose
+ (cute string-join <> "_")
+ (cute drop-right <> 1)
+ (cute string-split <> #\-))
+ (strip-prefix name+ver)))
+
+(define* (install #:key
+ inputs
+ outputs
+ name
+ build-per-environment
+ #:allow-other-keys)
+ "Install build artifacts in the store."
+ (let* ((lib-name (package-name->elixir-name name))
+ (lib-dir (string-append (elixir-libdir (assoc-ref outputs "out")) "/" lib-name))
+ (root (getenv "MIX_BUILD_ROOT"))
+ (env (if build-per-environment "prod" "shared")))
+ (mkdir-p lib-dir)
+ (copy-recursively (string-append (mix-build-dir root env) "/" lib-name) lib-dir
+ #:follow-symlinks? #t)))
+
+(define %standard-phases
+ (modify-phases gnu:%standard-phases
+ (delete 'bootstrap)
+ (delete 'configure)
+ (add-after 'install-locale 'set-mix-env set-mix-env)
+ (add-after 'set-mix-env 'set-elixir-version set-elixir-version)
+ (replace 'unpack unpack)
+ (replace 'build build)
+ (replace 'check check)
+ (add-before 'install 'remove-mix-dirs remove-mix-dirs)
+ (replace 'install install)))
+
+(define* (mix-build #:key inputs (phases %standard-phases)
+ #:allow-other-keys #:rest args)
+ "Build the given Mix package, applying all of PHASES in order."
+ (apply gnu:gnu-build #:inputs inputs #:phases phases args))
+
+;;; mix-build-system.scm ends here