diff options
| -rw-r--r-- | Makefile.am | 1 | ||||
| -rw-r--r-- | doc/guix.texi | 18 | ||||
| -rw-r--r-- | guix/docker.scm | 127 | ||||
| -rw-r--r-- | guix/scripts/archive.scm | 17 |
4 files changed, 161 insertions, 2 deletions
diff --git a/Makefile.am b/Makefile.am index 1a66fff505..3e147df2e0 100644 --- a/Makefile.am +++ b/Makefile.am @@ -160,6 +160,7 @@ MODULES = \ if HAVE_GUILE_JSON MODULES += \ + guix/docker.scm \ guix/import/github.scm \ guix/import/json.scm \ guix/import/crate.scm \ diff --git a/doc/guix.texi b/doc/guix.texi index adc7fefcae..e52382e976 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -2394,7 +2394,7 @@ what you should use in this case (@pxref{Invoking guix copy}). @cindex nar, archive format @cindex normalized archive (nar) -Archives are stored in the ``normalized archive'' or ``nar'' format, which is +By default archives are stored in the ``normalized archive'' or ``nar'' format, which is comparable in spirit to `tar', but with differences that make it more appropriate for our purposes. First, rather than recording all Unix metadata for each file, the nar format only mentions @@ -2410,6 +2410,9 @@ verifies the signature and rejects the import in case of an invalid signature or if the signing key is not authorized. @c FIXME: Add xref to daemon doc about signatures. +Optionally, archives can be exported as a Docker image in the tar +archive format using @code{--format=docker}. + The main options are: @table @code @@ -2438,6 +2441,19 @@ Read a list of store file names from the standard input, one per line, and write on the standard output the subset of these files missing from the store. +@item -f +@item --format=@var{FMT} +@cindex docker, export +@cindex export format +Specify the export format. Acceptable arguments are @code{nar} and +@code{docker}. The default is the nar format. When the format is +@code{docker}, recursively export the specified store directory as a +Docker image in tar archive format, as specified in +@uref{https://github.com/docker/docker/blob/master/image/spec/v1.2.md, +version 1.2.0 of the Docker Image Specification}. Using +@code{--format=docker} implies @code{--recursive}. The generated +archive can be loaded by Docker using @command{docker load}. + @item --generate-key[=@var{parameters}] @cindex signing, archives Generate a new key pair for the daemon. This is a prerequisite before diff --git a/guix/docker.scm b/guix/docker.scm new file mode 100644 index 0000000000..dbe1e5351c --- /dev/null +++ b/guix/docker.scm @@ -0,0 +1,127 @@ +;;; GNU Guix --- Functional package management for GNU +;;; Copyright © 2017 Ricardo Wurmus <rekado@elephly.net> +;;; +;;; 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 docker) + #:use-module (guix hash) + #:use-module (guix store) + #:use-module (guix utils) + #:use-module ((guix build utils) + #:select (delete-file-recursively + with-directory-excursion)) + #:use-module (json) + #:use-module (rnrs bytevectors) + #:use-module (ice-9 match) + #:export (build-docker-image)) + +;; Generate a 256-bit identifier in hexadecimal encoding for the Docker image +;; containing the closure at PATH. +(define docker-id + (compose bytevector->base16-string sha256 string->utf8)) + +(define (layer-diff-id layer) + "Generate a layer DiffID for the given LAYER archive." + (string-append "sha256:" (bytevector->base16-string (file-sha256 layer)))) + +;; This is the semantic version of the JSON metadata schema according to +;; https://github.com/docker/docker/blob/master/image/spec/v1.2.md +;; It is NOT the version of the image specification. +(define schema-version "1.0") + +(define (image-description id time) + "Generate a simple image description." + `((id . ,id) + (created . ,time) + (container_config . #nil))) + +(define (generate-tag path) + "Generate an image tag for the given PATH." + (match (string-split (basename path) #\-) + ((hash name . rest) (string-append name ":" hash)))) + +(define (manifest path id) + "Generate a simple image manifest." + `(((Config . "config.json") + (RepoTags . (,(generate-tag path))) + (Layers . (,(string-append id "/layer.tar")))))) + +;; According to the specifications this is required for backwards +;; compatibility. It duplicates information provided by the manifest. +(define (repositories path id) + "Generate a repositories file referencing PATH and the image ID." + `((,(generate-tag path) . ((latest . ,id))))) + +;; See https://github.com/opencontainers/image-spec/blob/master/config.md +(define (config layer time arch) + "Generate a minimal image configuration for the given LAYER file." + ;; "architecture" must be values matching "platform.arch" in the + ;; runtime-spec at + ;; https://github.com/opencontainers/runtime-spec/blob/v1.0.0-rc2/config.md#platform + `((architecture . ,arch) + (comment . "Generated by GNU Guix") + (created . ,time) + (config . #nil) + (container_config . #nil) + (os . "linux") + (rootfs . ((type . "layers") + (diff_ids . (,(layer-diff-id layer))))))) + +(define* (build-docker-image path #:key system) + "Generate a Docker image archive from the given store PATH. The image +contains the closure of the given store item." + (let ((id (docker-id path)) + (time (strftime "%FT%TZ" (localtime (current-time)))) + (name (string-append (getcwd) + "/docker-image-" (basename path) ".tar")) + (arch (match system + ("x86_64-linux" "amd64") + ("i686-linux" "386") + ("armhf-linux" "arm") + ("mips64el-linux" "mips64le")))) + (and (call-with-temporary-directory + (lambda (directory) + (with-directory-excursion directory + ;; Add symlink from /bin to /gnu/store/.../bin + (symlink (string-append path "/bin") "bin") + + (mkdir id) + (with-directory-excursion id + (with-output-to-file "VERSION" + (lambda () (display schema-version))) + (with-output-to-file "json" + (lambda () (scm->json (image-description id time)))) + + ;; Wrap it up + (let ((items (with-store store + (requisites store (list path))))) + (and (zero? (apply system* "tar" "-cf" "layer.tar" + (cons "../bin" items))) + (delete-file "../bin")))) + + (with-output-to-file "config.json" + (lambda () + (scm->json (config (string-append id "/layer.tar") + time arch)))) + (with-output-to-file "manifest.json" + (lambda () + (scm->json (manifest path id)))) + (with-output-to-file "repositories" + (lambda () + (scm->json (repositories path id))))) + (and (zero? (system* "tar" "-C" directory "-cf" name ".")) + (begin (delete-file-recursively directory) #t)))) + name))) diff --git a/guix/scripts/archive.scm b/guix/scripts/archive.scm index 7e432351ed..6eba9e0008 100644 --- a/guix/scripts/archive.scm +++ b/guix/scripts/archive.scm @@ -1,5 +1,6 @@ ;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2013, 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2017 Ricardo Wurmus <rekado@elephly.net> ;;; ;;; This file is part of GNU Guix. ;;; @@ -30,6 +31,7 @@ #:use-module (guix ui) #:use-module (guix pki) #:use-module (guix pk-crypto) + #:use-module (guix docker) #:use-module (guix scripts) #:use-module (guix scripts build) #:use-module (gnu packages) @@ -63,6 +65,8 @@ Export/import one or more packages from/to the store.\n")) (display (_ " --export export the specified files/packages to stdout")) (display (_ " + --format=FMT export files/packages in the specified format FMT")) + (display (_ " -r, --recursive combined with '--export', include dependencies")) (display (_ " --import import from the archive passed on stdin")) @@ -117,6 +121,9 @@ Export/import one or more packages from/to the store.\n")) (option '("export") #f #f (lambda (opt name arg result) (alist-cons 'export #t result))) + (option '(#\f "format") #t #f + (lambda (opt name arg result . rest) + (alist-cons 'format arg result))) (option '(#\r "recursive") #f #f (lambda (opt name arg result) (alist-cons 'export-recursive? #t result))) @@ -331,7 +338,15 @@ the input port." (else (with-store store (cond ((assoc-ref opts 'export) - (export-from-store store opts)) + (cond ((equal? (assoc-ref opts 'format) "docker") + (match (car opts) + (('argument . (? store-path? item)) + (format #t "~a\n" + (build-docker-image + item + #:system (assoc-ref opts 'system)))) + (_ (leave (_ "argument must be a direct store path~%"))))) + (_ (export-from-store store opts)))) ((assoc-ref opts 'import) (import-paths store (current-input-port))) ((assoc-ref opts 'missing) |