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+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2019 by Amar Singh <nly@disroot.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; This program 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.
+;;;
+;;; This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
+
+(define-module (guix import golang))
+(use-modules
+ (srfi srfi-1) ;; fold
+ (ice-9 rdelim) ;; read-string
+ (guix import github) ;; latest-release
+ (guix utils) ;; string-replace-substring
+ (guix memoization) ;; memoize network operations
+ (guix download) ;; download-to-store
+ ((guix import utils) #:prefix utils:) ;; hash
+ (guix packages) ;; packages
+ ((guix licenses) #:prefix license:) ;; licenses
+ (guix build-system) ;; build-system printer
+ (guix build-system go) ;; go-build-system
+ (guix store) ;; with-store
+ ;; (gnu packages golang) ;; inherit (simple) go package
+ (ice-9 textual-ports) ;; to parse readme.md
+ (ice-9 popen) ;; open-input-ouput-pipe
+ (web uri) ;; uri->string
+ (srfi srfi-26) ;; cut
+ )
+
+;;; To use, simply:
+;;; 1. (load "golang.scm")
+;;; 2. (define go-package (make-package go-name*))
+;;; 3. (package-sexp go-package)
+
+;;; STATUS
+;;; 1. latest-release DONE
+;;; 1.b latest-commit PENDING/STALLED
+;;; 2. go-name->guix-name DONE
+;;; 2.b style go-github-com-user-project DONE
+;;; 4. go-name->url DONE
+;;; 4.b go-name->tarball DONE
+;;; 5. go-name->sha256 (go-name version) DONE
+;;; 6. go-name->synopsis DONE
+;;; 7. go-name->description DONE
+;;; 4-7.b. Memoize, network procedures DONE
+;;; 6-7.b try to extract sentences. TODO
+;;; 8. go-name->license TODO
+;;; 9. go-name->inputs DONE
+;;; 9.b. inputs alist DONE
+;;; 10. package-sexp DONE
+;;; 10.a origin-sexp DONE
+;;; 11. Package Builds TODO
+
+(define-public go-name* "github.com/gohugoio/hugo") ;; for tests
+
+(define* (go-name->url go-name #:rest args)
+ (if (string-contains go-name ".")
+ (uri->string (string->uri (apply string-append
+ "https://" go-name args)))
+ #f))
+
+(define (go-name->tarball go-name version)
+ (go-name->url go-name "/archive/v"
+ version ".tar.gz"))
+
+(define* (string-replace-substrings string substrings
+ #:optional (replacement "-"))
+ (if (null-list? substrings)
+ string
+ ((cut string-replace-substring <> (car substrings) replacement)
+ (string-replace-substrings string (cdr substrings)))))
+
+;;; Possible remove @@ if upstream exports the symbols
+(define (go-name->guix-name go-name)
+ (string-append "go-"
+ (string-replace-substrings go-name '("." "/") "-")))
+
+;;; Slow; accesses the network; memoized
+(define latest-release
+ (memoize
+ (lambda (go-name)
+ ((@@ (guix import github) latest-released-version)
+ (go-name->url go-name)
+ (go-name->guix-name go-name)))))
+
+;;; Slow; downloads the url from network; memoized
+(define url->store
+ (@@ (guix import cran) download))
+
+;;; Slow; download src tarball from network, returns base32 nix-hash;
+;;; memoized
+(define (go-name->sha256 go-name version)
+ (utils:guix-hash-url (url->store (go-name->tarball go-name version))))
+
+;;; Slow; network access; memoized
+(define go-name->readme-string
+ (memoize
+ (lambda (go-name)
+ (define (go-name->readme go-name)
+ (go-name->url "raw.githubusercontent.com"
+ ;; TODO, detect the domain
+ (substring go-name
+ (string-length "github.com"))
+ "/master/"
+ "README.md"))
+ (call-with-input-file (url->store (go-name->readme go-name))
+ read-string))))
+
+;;; TODO: try to match the first sentence.
+(define (go-name->synopsis go-name)
+ (substring (go-name->readme-string go-name) 0 100))
+
+;;; TODO: try to match the the next two sentences.
+(define (go-name->description go-name)
+ (substring (go-name->readme-string go-name) 100 300))
+
+(define shell-command
+ (lambda* (command #:rest args)
+ (let* ((cmd (string-join (cons command (delete #f (delete '() args))) " "))
+ (port (open-input-output-pipe cmd))
+ (result (read-string port))
+ (exit-code (close-pipe port)))
+ (and (zero? exit-code)
+ (string-split (string-trim-right result) #\newline)))))
+
+(define go-name->inputs
+ (lambda (go-name)
+ (let ((recursive-depends "-f '{{ join .Deps \"\\n\" }}'")
+ (direct-depends "-f '{{ join .Imports \"\\n\" }}'")
+ (go-command (car (shell-command "which go"))))
+ (shell-command go-command "list" direct-depends go-name))))
+
+;;; License
+(define (string->license license-string)
+ ((@@ (guix import cran) string->license) (string-upcase license-string)))
+
+;;; For inputs
+(define format-inputs
+ (@@ (guix import cran) format-inputs))
+
+(define-public (make-go-package go-name)
+ ;; Do the expensive operations only once; query network for latest
+ ;; version
+ (let* ((version (latest-release go-name))
+ (sha256 (go-name->sha256 go-name version))
+ (readme-string (go-name->readme-string go-name)))
+ (package
+ ;; (inherit go-github-com-alsm-ioprogress)
+ (name
+ (string-append "go-" go-name))
+ (version version)
+ (source
+ (origin (method url-fetch)
+ (uri (go-name->tarball go-name version))
+ (sha256 (base32 sha256))))
+ (home-page
+ (go-name->url go-name))
+ (build-system
+ go-build-system)
+ (arguments
+ `(#:import-path ,go-name))
+ ;; TODO: make inputs into (unquote ..) form
+ (inputs
+ (format-inputs (map go-name->guix-name (go-name->inputs go-name))))
+ (synopsis (go-name->synopsis go-name))
+ (description (go-name->description go-name))
+ ;; TODO: license
+ (license license:expat)
+ )))
+
+(define (filter-newlines string)
+ (string-filter (lambda (x) (not (equal? x #\newline))) string))
+
+(define bv->nix-base32 (@@ (guix packages)
+ bytevector->nix-base32-string))
+
+(define (origin-sexp origin)
+ `(origin
+ (method url-fetch)
+ (uri ,(origin-uri origin))
+ (sha256 (base32 ,(bv->nix-base32 (origin-sha256 origin))))
+ (file-name ,(origin-file-name origin))
+ (patches ,(origin-patches origin))
+ (snippet ,(origin-snippet origin))
+ (patch-flags ,(origin-patch-flags origin))
+ (patch-inputs ,(origin-patch-inputs origin))
+ (modules ,(origin-modules origin))
+ (patch-guile ,(origin-patch-guile origin))))
+
+(define (build-system-sexp build-system)
+ (symbol-append (build-system-name build-system) '-build-system))
+
+(define-public (package-sexp package)
+ `(package
+ (name ,(package-name package))
+ (version ,(package-version package))
+ (source ,(origin-sexp (package-source package)))
+ (home-page ,(package-home-page package))
+ (build-system ,(build-system-sexp (package-build-system package)))
+ (arguments ,(package-arguments package))
+ (synopsis ,(filter-newlines (package-synopsis package)))
+ (description ,(filter-newlines (package-description package)))
+ (inputs ,(format-inputs (map car (package-inputs package))))
+ (native-inputs ,(format-inputs (map car (package-native-inputs package))))
+ (propagated-inputs ,(format-inputs (map car (package-propagated-inputs package))))))
+
+;;; golang.scm ends here