import: Add Go importer

5 files changed, 470 insertions, 6 deletions

diff --git a/Makefile.am b/Makefile.am
index 1acf0b12d0..ab67221905 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -188,8 +188,9 @@ MODULES =					\
   guix/import/cabal.scm				\
   guix/import/cran.scm				\
   guix/import/hackage.scm			\
-  guix/import/elpa.scm   			\
-  guix/import/texlive.scm   			\
+  guix/import/elpa.scm				\
+  guix/import/texlive.scm			\
+  guix/import/gopkg.scm				\
   guix/scripts.scm				\
   guix/scripts/download.scm			\
   guix/scripts/perform-download.scm		\
@@ -214,8 +215,9 @@ MODULES =					\
   guix/scripts/import/gnu.scm			\
   guix/scripts/import/nix.scm			\
   guix/scripts/import/hackage.scm		\
-  guix/scripts/import/elpa.scm  		\
-  guix/scripts/import/texlive.scm  		\
+  guix/scripts/import/elpa.scm			\
+  guix/scripts/import/texlive.scm		\
+  guix/scripts/import/gopkg.scm			\
   guix/scripts/environment.scm			\
   guix/scripts/publish.scm			\
   guix/scripts/edit.scm				\
diff --git a/doc/guix.texi b/doc/guix.texi
index 12346c4b8e..1112b81e5f 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -20,7 +20,7 @@ Copyright @copyright{} 2014, 2015, 2016 Alex Kost@*
 Copyright @copyright{} 2015, 2016 Mathieu Lirzin@*
 Copyright @copyright{} 2014 Pierre-Antoine Rault@*
 Copyright @copyright{} 2015 Taylan Ulrich Bayırlı/Kammer@*
-Copyright @copyright{} 2015, 2016, 2017 Leo Famulari@*
+Copyright @copyright{} 2015, 2016, 2017, 2018 Leo Famulari@*
 Copyright @copyright{} 2015, 2016, 2017, 2018 Ricardo Wurmus@*
 Copyright @copyright{} 2016 Ben Woodcroft@*
 Copyright @copyright{} 2016, 2017, 2018 Chris Marusich@*
@@ -7179,6 +7179,13 @@ Import metadata from the crates.io Rust package repository
 @cindex OCaml
 Import metadata from the @uref{https://opam.ocaml.org/, OPAM} package
 repository used by the OCaml community.
+
+@item gopkg
+@cindex gopkg
+@cindex Golang
+@cindex Go
+Import metadata from the @uref{https://gopkg.in/, gopkg} package
+versioning service used by some Go software.
 @end table
 
 The structure of the @command{guix import} code is modular.  It would be
diff --git a/guix/import/gopkg.scm b/guix/import/gopkg.scm
new file mode 100644
index 0000000000..204bf18abb
--- /dev/null
+++ b/guix/import/gopkg.scm
@@ -0,0 +1,356 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2018 Pierre-Antoine Rouby <pierre-antoine.rouby@inria.fr>
+;;;
+;;; 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/>.
+
+(define-module (guix import gopkg)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 regex)
+  #:use-module ((ice-9 rdelim) #:select (read-line))
+  #:use-module (srfi srfi-11)
+  #:use-module (texinfo string-utils) ; transform-string
+  #:use-module (gcrypt hash)
+  ;; #:use-module (guix hash)
+  #:use-module (guix base32)
+  #:use-module (guix serialization)
+  #:use-module (guix utils)
+  #:use-module (guix build utils)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:export (gopkg->guix-package))
+
+(define (vcs-file? file stat)
+  ;; TODO: Factorize
+  (case (stat:type stat)
+    ((directory)
+     (member (basename file) '(".bzr" ".git" ".hg" ".svn" "CVS")))
+    ((regular)
+     ;; Git sub-modules have a '.git' file that is a regular text file.
+     (string=? (basename file) ".git"))
+    (else
+     #f)))
+
+(define (file->hash-base32 file)
+  "Return hash of FILE in nix base32 sha256 format.  If FILE is a directory,
+exclude vcs files."
+  (let-values (((port get-hash) (open-sha256-port)))
+    (write-file file port #:select? (negate vcs-file?))
+    (force-output port)
+    (bytevector->nix-base32-string (get-hash))))
+
+(define (git->hash url commit file)
+  "Clone git repository and return FILE hash in nix base32 sha256 format."
+  (if (not (file-exists? (string-append file "/.git")))
+      (git-fetch url commit file #:recursive? #f))
+  (file->hash-base32 file))
+
+(define (git-ref->commit path tag)
+  "Return commit number coresponding to git TAG.  Return \"XXX\" if tag is not
+found."
+  (define (loop port)
+    (let ((line (read-line port)))
+      (cond
+       ((eof-object? line)              ; EOF
+        (begin
+          (close-port port)
+          "XXX"))
+       ((string-match tag line)         ; Match tag
+        (let ((commit (car (string-split (transform-string line #\tab " ")
+                                         #\ ))))
+          commit))
+       (else                            ; Else
+        (loop port)))))
+
+  (let ((file (if (file-exists? (string-append path "/.git/packed-refs"))
+                  (string-append path "/.git/packed-refs")
+                  (string-append path "/.git/FETCH_HEAD"))))
+    (loop (open-input-file file))))
+
+(define* (git-fetch url commit directory
+                    #:key (git-command "git") recursive?)
+  "Fetch COMMIT from URL into DIRECTORY.  COMMIT must be a valid Git commit
+identifier.  When RECURSIVE? is true, all the sub-modules of URL are fetched,
+recursively.  Return #t on success, #f otherwise."
+  (mkdir-p directory)
+  
+  (with-directory-excursion directory
+    (invoke git-command "init")
+    (invoke git-command "remote" "add" "origin" url)
+    (if (zero? (system* git-command "fetch" "--depth" "1" "origin" commit))
+        (invoke git-command "checkout" "FETCH_HEAD")
+        (begin
+          (invoke git-command "fetch" "origin")
+          (if (not (zero? (system* git-command "checkout" commit)))
+              (let ((commit-hash (git-ref->commit directory commit)))
+                (invoke git-command "checkout" "master")
+                (if (not (equal? "XXX" commit-hash)) ;HACK else stay on master
+                    (zero? (system* git-command "checkout" commit-hash))))
+              #t)))))
+
+;;
+;; Append attributes.
+;;
+
+(define (append-inputs inputs name)
+  "Return list with new input corresponding to package NAME."
+  (let ((unquote-name (list 'unquote (string->symbol name))))
+    (append inputs (list (list name unquote-name)))))
+
+;;
+;; Parse attributes.
+;;
+
+(define (url->package-name url)
+  "Compute URL and return package name."
+  (let* ((url-no-slash (string-replace-substring url "/" "-"))
+         (url-no-slash-no-dot (string-replace-substring url-no-slash
+                                                        "." "-")))
+    (string-downcase (string-append "go-" url-no-slash-no-dot))))
+
+(define (cut-url url)
+  "Return URL without protocol prefix and git file extension."
+  (string-replace-substring
+   (cond
+    ((string-match "http://"  url)
+     (string-replace-substring url "http://" ""))
+    ((string-match "https://" url)
+     (string-replace-substring url "https://" ""))
+    ((string-match "git://"   url)
+     (string-replace-substring url "git://" ""))
+    (else
+     url))
+   ".git" ""))
+
+(define (url->dn url)
+  "Return the web site DN form url 'gnu.org/software/guix' --> 'gnu.org'"
+  (car (string-split url #\/)))
+
+(define (url->git-url url)
+  (string-append "https://" url ".git"))
+
+(define (comment? line)
+  "Return #t if LINE start with comment delimiter, else return #f."
+  (eq? (string-ref (string-trim line) 0) #\#))
+
+(define (empty-line? line)
+  "Return #t if LINE is empty, else #f."
+  (string-null? (string-trim line)))
+
+(define (attribute? line attribute)
+  "Return #t if LINE contain ATTRIBUTE."
+  (equal? (string-trim-right
+           (string-trim
+            (car (string-split line #\=)))) attribute))
+
+(define (attribute-by-name line name)
+  "Return attribute value corresponding to NAME."
+  (let* ((line-no-attribut-name (string-replace-substring
+                                 line
+                                 (string-append name " = ") ""))
+         (value-no-double-quote (string-replace-substring
+                                 line-no-attribut-name
+                                 "\"" "")))
+    (string-trim value-no-double-quote)))
+
+;;
+;; Packages functions.
+;;
+
+(define (make-go-sexp->package packages dependencies
+                               name url version revision
+                               commit str-license home-page
+                               git-url is-dep? hash)
+  "Create Guix sexp package for Go software NAME. Return new package sexp."
+  (define (package-inputs)
+    (if (not is-dep?)
+        `((native-inputs ,(list 'quasiquote dependencies)))
+        '()))
+
+  (values
+   `(define-public ,(string->symbol name)
+      (let ((commit ,commit)
+            (revision ,revision))
+        (package
+          (name ,name)
+          (version (git-version ,version revision commit))
+          (source (origin
+                    (method git-fetch)
+                    (uri (git-reference
+                          (url ,git-url)
+                          (commit commit)))
+                    (file-name (git-file-name name version))
+                    (sha256
+                     (base32
+                      ,hash))))
+          (build-system go-build-system)
+          (arguments
+           '(#:import-path ,url))
+          ,@(package-inputs)
+          (home-page ,home-page)
+          (synopsis "XXX")
+          (description "XXX")
+          (license #f))))))
+
+(define (create-package->packages+dependencies packages dependencies
+                                               url version directory
+                                               revision commit
+                                               constraint? is-dep?)
+  "Return packages and dependencies with new package sexp corresponding to
+URL."
+  (call-with-temporary-directory
+   (lambda (dir)
+     (let ((name      (url->package-name url))
+           (home-page (string-append "https://" url))
+           (git-url   (url->git-url url))
+           (synopsis    "XXX")
+           (description "XXX")
+           (license     "XXX"))
+       (let ((hash (git->hash (url->git-url url)
+                              commit
+                              dir))
+             (commit-hash (if (< (string-length commit) 40)
+                              (git-ref->commit dir
+                                               commit)
+                              commit)))
+         (values
+          (append packages
+                  (list
+                   (make-go-sexp->package packages dependencies
+                                          name url version
+                                          revision commit-hash
+                                          license home-page
+                                          git-url is-dep? hash)))
+          (if constraint?
+              (append-inputs dependencies name)
+              dependencies)))))))
+
+(define (parse-dependencies->packages+dependencies port constraint?
+                                                   packages dependencies)
+  "Parse one dependencies in PORT, and return packages and dependencies list."
+  (let ((url "XXX")
+        (version "0.0.0")
+        (revision "0")
+        (commit "XXX"))
+    (define (loop port url commit packages dependencies)
+      (let ((line (read-line port)))
+        (cond
+         ((eof-object? line)            ; EOF
+          (values packages dependencies))
+         ((empty-line? line)                               ; Empty line
+          (if (not (or (equal? "k8s.io" (url->dn url))     ; HACK bypass k8s
+                       (equal? "golang.org" (url->dn url)) ; HACK bypass golang
+                       (equal? "cloud.google.com" (url->dn url)))) ; HACK bypass cloud.google
+              (create-package->packages+dependencies packages dependencies
+                                                     url version port revision
+                                                     commit
+                                                     constraint? #t)
+              (values packages dependencies)))
+         ((comment? line)               ; Comment
+          (loop port url commit
+                packages dependencies))
+         ((attribute? line "name")      ; Name
+          (loop port
+                (attribute-by-name line "name")
+                commit
+                packages dependencies))
+         ((attribute? line "revision")  ; Revision
+          (loop port
+                url
+                (attribute-by-name line "revision")
+                packages dependencies))
+         ((attribute? line "version")   ; Version
+          (loop port
+                url
+                (attribute-by-name line "version")
+                packages dependencies))
+         ((attribute? line "branch")    ; Branch
+          (loop port
+                url
+                (attribute-by-name line "branch")
+                packages dependencies))
+         ((string-match "=" line)       ; Other options
+          (loop port url commit
+                packages dependencies))
+         (else (loop port url commit
+                     packages dependencies)))))
+    (loop port url commit
+          packages dependencies)))
+
+(define (parse-toml->packages+dependencies port packages dependencies)
+  "Read toml file on PORT and return all dependencies packages sexp and list
+of constraint dependencies."
+  (define (loop port packages dependencies)
+    (let ((line (read-line port)))
+      (cond
+       ((eof-object? line)              ; EOF
+        (values packages dependencies))
+       ((empty-line? line)              ; Empty line
+        (loop port packages dependencies))
+       ((comment? line)                 ; Comment
+        (loop port packages dependencies))
+       ((equal? line "[prune]")         ; Ignored
+        (loop port packages dependencies))
+       ((equal? "[[constraint]]" line)  ; Direct dependencies
+        (let-values (((packages dependencies)
+                      (parse-dependencies->packages+dependencies port #t
+                                                                 packages
+                                                                 dependencies)))
+          (loop port packages dependencies)))
+       ((equal? "[[override]]" line)    ; Dependencies of dependencies
+        (let-values (((packages dependencies)
+                      (parse-dependencies->packages+dependencies port #f
+                                                                 packages
+                                                                 dependencies)))
+          (loop port packages dependencies)))
+       (else (loop port packages dependencies)))))
+  (loop port packages dependencies))
+
+(define (gopkg-dep->packages+dependencies path)
+  "Open toml file if exist and parse it and return packages sexp and
+dependencies list. Or return two empty list if file not found."
+  (if (file-exists? path)
+      (let ((port (open-input-file path)))
+        (let-values (((packages dependencies)
+                      (parse-toml->packages+dependencies port
+                                                         '() '())))
+          (close-port port)
+          (values packages dependencies)))
+      (values '() '())))
+
+;;
+;; Entry point.
+;;
+
+(define (gopkg->guix-package url branch)
+  "Create package for git repository dans branch verison and all dependencies
+sexp packages with Gopkg.toml file."
+  (let ((name (url->package-name (cut-url url)))
+        (version "0.0.0")
+        (revision "0"))
+    (call-with-temporary-directory
+     (lambda (directory)
+       (git-fetch url branch directory #:recursive? #f)
+
+       (let-values (((packages dependencies)
+                     (gopkg-dep->packages+dependencies
+                      (string-append directory
+                                     "/Gopkg.toml"))))
+         (let-values (((packages dependencies)
+                       (create-package->packages+dependencies packages dependencies
+                                                              (cut-url url) version
+                                                              directory
+                                                              revision branch
+                                                              #f #f)))
+           (values packages)))))))
diff --git a/guix/scripts/import.scm b/guix/scripts/import.scm
index 0b326e1049..56b34971e3 100644
--- a/guix/scripts/import.scm
+++ b/guix/scripts/import.scm
@@ -75,7 +75,7 @@ rather than \\n."
 ;;;
 
 (define importers '("gnu" "nix" "pypi" "cpan" "hackage" "stackage" "elpa" "gem"
-                    "cran" "crate" "texlive" "json" "opam"))
+                    "cran" "crate" "texlive" "json" "opam" "gopkg"))
 
 (define (resolve-importer name)
   (let ((module (resolve-interface
diff --git a/guix/scripts/import/gopkg.scm b/guix/scripts/import/gopkg.scm
new file mode 100644
index 0000000000..9a39e58d78
--- /dev/null
+++ b/guix/scripts/import/gopkg.scm
@@ -0,0 +1,99 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2018 Pierre-Antoine Rouby <pierre-antoine.rouby@inria.fr>
+;;;
+;;; 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/>.
+
+(define-module (guix scripts import gopkg)
+  #:use-module (guix ui)
+  #:use-module (guix utils)
+  #:use-module (guix scripts)
+  #:use-module (guix import gopkg)
+  #:use-module (guix scripts import)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-11)
+  #:use-module (srfi srfi-37)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 format)
+  #:export (guix-import-gopkg))
+
+
+;;;
+;;; Command-line options.
+;;;
+
+(define %default-options
+  '())
+
+(define (show-help)
+  (display (G_ "Usage: guix import gopkg PACKAGE-URL BRANCH
+Import and convert the Git repository with TOML file to a Guix package
+using PACKAGE-URL and matching BRANCH.\n"))
+  (display (G_ "
+  -h, --help             display this help and exit"))
+  (display (G_ "
+  -V, --version          display version information and exit"))
+  (newline)
+  (show-bug-report-information))
+
+(define %options
+  ;; Specification of the command-line options.
+  (cons* (option '(#\h "help") #f #f
+                 (lambda args
+                   (show-help)
+                   (exit 0)))
+         (option '(#\V "version") #f #f
+                 (lambda args
+                   (show-version-and-exit "guix import gopkg")))
+         %standard-import-options))
+
+
+;;;
+;;; Entry point.
+;;;
+
+(define (guix-import-gopkg . args)
+  (define (parse-options)
+    ;; Return the alist of option values.
+    (args-fold* args %options
+                (lambda (opt name arg result)
+                  (leave (G_ "~A: unrecognized option~%") name))
+                (lambda (arg result)
+                  (alist-cons 'argument arg result))
+                %default-options))
+
+  (let* ((opts (parse-options))
+         (args (filter-map (match-lambda
+                            (('argument . value)
+                             value)
+                            (_ #f))
+                           (reverse opts))))
+    (match args
+      ((package-url branch)
+       (let ((sexp (gopkg->guix-package package-url branch)))
+         (unless sexp
+           (leave (G_ "failed to download meta-data for package '~a'~%")
+                  package-url))
+         sexp))
+      ((package-url)
+       (let ((sexp (gopkg->guix-package package-url "master")))
+         (unless sexp
+           (leave (G_ "failed to download meta-data for package '~a'~%")
+                  package-url))
+         sexp))
+      (()
+       (leave (G_ "too few arguments~%")))
+      ((many ...)
+       (leave (G_ "too many arguments~%"))))))