04/04: gx-download (DRAFT)

[Pierre Neidhardt]

ambrevar pushed a commit to branch wip-ipfs2
in repository guix.

commit 376a9fa08fa3ffb5a5ab0980acf75abdfc797486
Author: Pierre Neidhardt <address@hidden>
Date:   Wed Oct 17 18:56:38 2018 +0200

    gx-download (DRAFT)
---
 guix/build/gx.scm    |  60 +++++++++++++++++++++++
 guix/gx-download.scm | 131 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 191 insertions(+)

diff --git a/guix/build/gx.scm b/guix/build/gx.scm
new file mode 100644
index 0000000..4ba0197
--- /dev/null
+++ b/guix/build/gx.scm
@@ -0,0 +1,60 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2018 Pierre Neidhardt <address@hidden>
+;;;
+;;; 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 build gx)
+  #:use-module (guix build utils)
+  #:use-module (ice-9 popen)
+  #:export (gx-fetch))
+
+;;; Commentary:
+;;;
+;;; This is the build-side support code of (guix gx-download).  It allows a
+;;; gx hash to be fetched.
+;;;
+;;; Code:
+
+(define* (gx-fetch hash directory
+                   #:key (gx-command "gx"))
+  "Fetch IPFS HASH into DIRECTORY.  HASH must be a valid IPFS hash.
+Return #t on success, #f otherwise."
+
+  (mkdir-p directory)
+
+  (with-directory-excursion directory
+    ;; TODO: Silence verbose output.
+
+    ;; Initialization is interactive, but we can shut it up by piping it to
+    ;; nothing.
+    (let ((port (open-pipe* OPEN_WRITE gx-command "init")))
+      (display "\n" port)
+      (if (not (eqv? 0 (status:exit-val (close-pipe port))))
+          (error "Cannot initialize gx package")))
+
+    ;; Fetch to the "vendor" directory.
+    (let ((port (open-pipe* OPEN_WRITE gx-command "import" "--local" hash)))
+      (display "N\n" port)
+      (if (not (eqv? 0 (status:exit-val (close-pipe port))))
+          (error "Cannot import gx package")))
+
+    (delete-file "package.json")
+    (mkdir-p   "gx/ipfs")
+    (rename-file (string-append  "vendor/gx/ipfs/" hash) (string-append 
"gx/ipfs/" hash))
+    (delete-file-recursively "vendor")
+    #t))
+
+;;; gx.scm ends here
diff --git a/guix/gx-download.scm b/guix/gx-download.scm
new file mode 100644
index 0000000..4acf7bf
--- /dev/null
+++ b/guix/gx-download.scm
@@ -0,0 +1,131 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2018 Pierre Neidhardt <address@hidden>
+;;;
+;;; 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 gx-download)
+  #:use-module (guix gexp)
+  #:use-module (guix store)
+  #:use-module (guix monads)
+  #:use-module (guix records)
+  #:use-module (guix packages)
+  #:use-module (guix utils)
+  #:use-module (guix modules)
+  ;; #:autoload   (guix build-system gnu) (standard-packages)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 vlist)
+  #:use-module (srfi srfi-1)
+  #:export (gx-reference
+            gx-reference?
+            gx-reference-hash
+
+            gx-fetch
+            gx-version
+            gx-file-name))
+
+;;; Commentary:
+;;;
+;;; An <origin> method that uses gx to fetch a specific hash over IPFS.
+;;; See https://github.com/whyrusleeping/gx.
+;;; The hash is specified with a <gx-reference> object.
+;;;
+;;; Code:
+
+(define-record-type* <gx-reference>
+  gx-reference make-gx-reference
+  gx-reference?
+  (hash gx-reference-hash))
+
+(define (gx-package)
+  "Return the default gx package."
+  (let ((distro (resolve-interface '(gnu packages ipfs))))
+    (module-ref distro 'gx)))
+
+(define* (gx-fetch ref hash-algo hash
+                    #:optional name
+                    #:key (system (%current-system)) (guile (default-guile))
+                    (gx (gx-package)))
+  "Return a fixed-output derivation that fetches REF, a <gx-reference>
+object.  The output is expected to have recursive hash HASH of type
+HASH-ALGO (a symbol).  Use NAME as the file name, or a generic name if #f."
+  ;; (define inputs
+  ;;   ;; When doing 'git clone --recursive', we need sed, grep, etc. to be
+  ;;   ;; available so that 'git submodule' works.
+  ;;   ;; (if (git-reference-recursive? ref)
+  ;;   ;;     (standard-packages)
+  ;;   ;;     '())
+  ;;   )
+
+  ;; (define zlib
+  ;;   (module-ref (resolve-interface '(gnu packages compression)) 'zlib))
+
+  ;; (define config.scm
+  ;;   (scheme-file "config.scm"
+  ;;                #~(begin
+  ;;                    (define-module (guix config)
+  ;;                      #:export (%libz))
+
+  ;;                    (define %libz
+  ;;                      #+(file-append zlib "/lib/libz")))))
+
+  ;; (define modules
+  ;;   (cons `((guix config) => ,config.scm)
+  ;;         (delete '(guix config)
+  ;;                 (source-module-closure '((guix build git)
+  ;;                                          (guix build utils)
+  ;;                                          (guix build download-nar))))))
+
+  (define build
+    (with-imported-modules '((guix build gx)
+                             (guix build utils))
+      #~(begin
+          (use-modules (guix build gx)
+                       ;; (guix build utils)
+                       ;; (guix build download-nar)
+                       ;; (ice-9 match)
+                       )
+
+          ;; The 'git submodule' commands expects Coreutils, sed,
+          ;; grep, etc. to be in $PATH.
+          ;; (set-path-environment-variable "PATH" '("bin")
+          ;;                                (match '#+inputs
+          ;;                                  (((names dirs outputs ...) ...)
+          ;;                                   dirs)))
+
+          (or (gx-fetch '#$(gx-reference-hash ref)
+                         #$output
+                         #:gx-command (string-append #+gx "/bin/gx"))
+              ;; (download-nar #$output)
+              ))))
+
+  (mlet %store-monad ((guile (package->derivation guile system)))
+    (gexp->derivation (or name "gx-checkout") build
+                      #:system system
+                      #:local-build? #t
+                      #:hash-algo hash-algo
+                      #:hash hash
+                      #:recursive? #t
+                      #:guile-for-build guile)))
+
+(define (gx-version version revision hash)
+  "Return the version string for packages using gx-download."
+  (string-append version "-" revision "." (string-take hash 7)))
+
+(define (gx-file-name name version)
+  "Return the file-name for packages using gx-download."
+  (string-append name "-" version "-checkout"))
+
+;;; gx-download.scm ends here