gnu: Add restic.

* gnu/packages/backup.scm (restic): New variable.

gnu/packages/backup.scm

@@ -10,6 +10,7 @@
 ;;; Copyright © 2017 Christopher Allan Webber <cwebber@dustycloud.org>
 ;;; Copyright © 2017 Rutger Helling <rhelling@mykolab.com>
 ;;; Copyright © 2018 Mark H Weaver <mhw@netris.org>
+;;; Copyright © 2018 Oleg Pykhalov <go.wigust@gmail.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -32,6 +33,7 @@ (define-module (gnu packages backup)
   #:use-module (guix download)
   #:use-module (guix utils)
   #:use-module (guix build-system gnu)
+  #:use-module (guix build-system go)
   #:use-module (guix build-system python)
   #:use-module (gnu packages)
   #:use-module (gnu packages acl)
@@ -45,6 +47,7 @@ (define-module (gnu packages backup)
   #:use-module (gnu packages ftp)
   #:use-module (gnu packages glib)
   #:use-module (gnu packages gnupg)
+  #:use-module (gnu packages golang)
   #:use-module (gnu packages gperf)
   #:use-module (gnu packages guile)
   #:use-module (gnu packages linux)
@@ -822,3 +825,112 @@ (define write-man
 is like a time machine for your data. ")
     (license (license:fsf-free "file://COPYING"
                                "Open Software License 2.0"))))
+
+(define-public restic ; bundled / vendored dependencies
+  (package
+    (name "restic")
+    (version "0.9.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append
+                    "https://github.com/restic/restic/releases/download/"
+                    "v" version "/restic-" version ".tar.gz"))
+              (file-name (string-append name "-" version ".tar.gz"))
+              (sha256
+               (base32
+                "15f0rsm2lxk4lmn4773q28g49p68pqyyx0ccp7r556asan73p79m"))))
+    (build-system go-build-system)
+    (arguments
+     `(#:import-path "github.com/restic/restic"
+       #:unpack-path "github.com/restic"
+      ;; We don't need to install the source code for end-user applications.
+       #:install-source? #f
+       #:phases
+       (modify-phases %standard-phases
+         (replace 'build
+           (lambda* (#:key inputs #:allow-other-keys)
+             (with-directory-excursion (string-append
+                                        "src/github.com/restic/restic-"
+                                        ,version)
+               (invoke "go" "run" "build.go"))))
+
+         (replace 'install
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let ((out (assoc-ref outputs "out"))
+                   (src (string-append "src/github.com/restic/restic-"
+                                       ,version)))
+               (install-file (string-append src "/restic")
+                             (string-append out "/bin"))
+               #t)))
+
+         (add-after 'install 'install-docs
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (man "/share/man")
+                    (man-section (string-append man "/man"))
+                    (src (string-append "src/github.com/restic/restic-"
+                                        ,version "/doc/man/")))
+               ;; Install all the man pages to "out".
+               (for-each
+                 (lambda (file)
+                   (install-file file
+                                 (string-append out man-section
+                                                (string-take-right file 1))))
+                 (find-files src "\\.[1-9]"))
+               #t)))
+
+         (add-after 'install-docs 'install-shell-completion
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (bin (string-append out "/bin"))
+                    (etc (string-append out "/etc"))
+                    (share (string-append out "/share")))
+               (for-each
+                (lambda (shell)
+                  (let* ((shell-name (symbol->string shell))
+                         (dir (string-append "etc/completion/" shell-name)))
+                    (mkdir-p dir)
+                    (invoke (string-append bin "/restic") "generate"
+                            (string-append "--" shell-name "-completion")
+                            (string-append dir "/"
+                                           (case shell
+                                             ((bash) "restic")
+                                             ((zsh) "_restic"))))))
+                '(bash zsh))
+               (with-directory-excursion "etc/completion"
+                 (install-file "bash/restic"
+                               (string-append etc "/bash_completion.d"))
+                 (install-file "zsh/_restic"
+                               (string-append share "/zsh/site-functions")))
+               #t))))))
+    (home-page "https://restic.net/")
+    (synopsis "Backup program with multiple revisions, encryption and more")
+    (description "Restic is a program that does backups right and was designed
+with the following principles in mind:
+
+@itemize
+@item Easy: Doing backups should be a frictionless process, otherwise you
+might be tempted to skip it.  Restic should be easy to configure and use, so
+that, in the event of a data loss, you can just restore it.  Likewise,
+restoring data should not be complicated.
+
+@item Fast: Backing up your data with restic should only be limited by your
+network or hard disk bandwidth so that you can backup your files every day.
+Nobody does backups if it takes too much time.  Restoring backups should only
+transfer data that is needed for the files that are to be restored, so that
+this process is also fast.
+
+@item Verifiable: Much more important than backup is restore, so restic
+enables you to easily verify that all data can be restored.  @item Secure:
+Restic uses cryptography to guarantee confidentiality and integrity of your
+data.  The location the backup data is stored is assumed not to be a trusted
+environment (e.g.  a shared space where others like system administrators are
+able to access your backups).  Restic is built to secure your data against
+such attackers.
+
+@item Efficient: With the growth of data, additional snapshots should only
+take the storage of the actual increment.  Even more, duplicate data should be
+de-duplicated before it is actually written to the storage back end to save
+precious backup space.
+@end itemize")
+    (license license:bsd-2)))