summaryrefslogtreecommitdiff
path: root/guix/scripts/time-machine.scm
blob: 87000d82ec007d7b0d91b6b0e82486dd7458d7fc (about) (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2019 Konrad Hinsen <konrad.hinsen@fastmail.net>
;;; Copyright © 2019, 2020, 2021, 2023 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2021 Simon Tournier <zimon.toutoune@gmail.com>
;;; Copyright © 2023 Maxim Cournoyer <maxim.cournoyer@gmail.com>
;;;
;;; 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 time-machine)
  #:use-module (guix channels)
  #:use-module (guix diagnostics)
  #:use-module (guix ui)
  #:use-module (guix scripts)
  #:use-module (guix inferior)
  #:use-module (guix store)
  #:use-module (guix status)
  #:use-module ((guix git)
                #:select (update-cached-checkout with-git-error-handling))
  #:use-module ((guix utils)
                #:select (%current-system))
  #:use-module ((guix scripts pull)
                #:select (channel-list))
  #:use-module ((guix scripts build)
                #:select (%standard-build-options
                          show-build-options-help
                          set-build-options-from-command-line))
  #:use-module (ice-9 match)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-26)
  #:use-module (srfi srfi-34)
  #:use-module (srfi srfi-37)
  #:use-module (srfi srfi-71)
  #:export (guix-time-machine))

;;; The required inferiors mechanism relied on by 'guix time-machine' was
;;; firmed up in v1.0.0; it is the oldest, safest commit that can be travelled
;;; to.
(define %oldest-possible-commit
  "6298c3ffd9654d3231a6f25390b056483e8f407c") ;v1.0.0


;;;
;;; Command-line options.
;;;

(define (show-help)
  (display (G_ "Usage: guix time-machine [OPTION] -- COMMAND ARGS...
Execute COMMAND ARGS... in an older version of Guix.\n"))
  (display (G_ "
  -C, --channels=FILE    deploy the channels defined in FILE"))
  (display (G_ "
  -q, --no-channel-files
                         inhibit loading of user and system 'channels.scm'"))
  (display (G_ "
      --url=URL          use the Git repository at URL"))
  (display (G_ "
      --commit=COMMIT    use the specified COMMIT"))
  (display (G_ "
      --branch=BRANCH    use the tip of the specified BRANCH"))
  (display (G_ "
      --disable-authentication
                         disable channel authentication"))
  (newline)
  (show-build-options-help)
  (newline)
  (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
  ;; Specifications of the command-line options.
  (cons* (option '(#\C "channels") #t #f
                 (lambda (opt name arg result)
                   (alist-cons 'channel-file arg result)))
         (option '(#\q "no-channel-files") #f #f
                 (lambda (opt name arg result)
                   (alist-cons 'ignore-channel-files? #t result)))
         (option '("url") #t #f
                 (lambda (opt name arg result)
                   (alist-cons 'repository-url arg
                               (alist-delete 'repository-url result))))
         (option '("commit") #t #f
                 (lambda (opt name arg result)
                   (alist-cons 'ref `(tag-or-commit . ,arg) result)))
         (option '("branch") #t #f
                 (lambda (opt name arg result)
                   (alist-cons 'ref `(branch . ,arg) result)))
         (option '("disable-authentication") #f #f
                 (lambda (opt name arg result)
                   (alist-cons 'authenticate-channels? #f result)))
         (option '(#\h "help") #f #f
                 (lambda args
                   (show-help)
                   (exit 0)))
         (option '(#\V "version") #f #f
                 (lambda args
                   (show-version-and-exit "guix time-machine")))

         %standard-build-options))

(define %default-options
  ;; Alist of default option values.
  `((system . ,(%current-system))
    (substitutes? . #t)
    (offload? . #t)
    (print-build-trace? . #t)
    (print-extended-build-trace? . #t)
    (multiplexed-build-output? . #t)
    (authenticate-channels? . #t)
    (graft? . #t)
    (debug . 0)
    (verbosity . 1)))

(define (parse-args args)
  "Parse the list of command line arguments ARGS."
  ;; The '--' token is used to separate the command to run from the rest of
  ;; the operands.
  (let-values (((args command) (break (cut string=? "--" <>) args)))
    (let ((opts (parse-command-line args %options
                                    (list %default-options))))
      (when (assoc-ref opts 'argument)
        (leave (G_ "~A: extraneous argument~%")
               (assoc-ref opts 'argument)))

      (match command
        (() opts)
        (("--") opts)
        (("--" command ...) (alist-cons 'exec command opts))))))


;;;
;;; Entry point.
;;;

(define-command (guix-time-machine . args)
  (synopsis "run commands from a different revision")

  (with-error-handling
    (with-git-error-handling
     (let* ((opts         (parse-args args))
            (channels     (channel-list opts))
            (command-line (assoc-ref opts 'exec))
            (ref          (assoc-ref opts 'ref))
            (substitutes?  (assoc-ref opts 'substitutes?))
            (authenticate? (assoc-ref opts 'authenticate-channels?)))

       (define (validate-guix-channel channels)
         "Finds the Guix channel among CHANNELS, and validates that REF as
captured from the closure, a git reference specification such as a commit hash
or tag associated to CHANNEL, is valid and new enough to satisfy the 'guix
time-machine' requirements.  A `formatted-message' condition is raised
otherwise."
         (let* ((guix-channel (find guix-channel? channels))
                (checkout commit relation (update-cached-checkout
                                           (channel-url guix-channel)
                                           #:ref (or ref '())
                                           #:starting-commit
                                           %oldest-possible-commit)))
           (unless (memq relation '(ancestor self))
             (raise (formatted-message
                     (G_ "cannot travel past commit `~a' from May 1st, 2019")
                     (string-take %oldest-possible-commit 12))))))

       (when command-line
         (let* ((directory
                 (with-store store
                   (with-status-verbosity (assoc-ref opts 'verbosity)
                     (with-build-handler (build-notifier #:use-substitutes?
                                                         substitutes?
                                                         #:verbosity
                                                         (assoc-ref opts 'verbosity)
                                                         #:dry-run? #f)
                       (set-build-options-from-command-line store opts)
                       (cached-channel-instance store channels
                                                #:authenticate? authenticate?
                                                #:validate-channels
                                                validate-guix-channel)))))
                (executable (string-append directory "/bin/guix")))
           (apply execl (cons* executable executable command-line))))))))