blob: 32bf6085a5e219c532062d16754c92595526c10c (
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
|
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2020, 2021 Mathieu Othacehe <othacehe@gnu.org>
;;; Copyright © 2021 Simon Tournier <zimon.toutoune@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 discover)
#:use-module (guix avahi)
#:use-module (guix config)
#:use-module (guix scripts)
#:use-module (guix ui)
#:use-module (guix utils)
#:use-module (guix build utils)
#:use-module (guix scripts publish)
#:use-module (avahi)
#:use-module (ice-9 rdelim)
#:use-module (srfi srfi-37)
#:export (read-substitute-urls
guix-discover))
(define (show-help)
(format #t (G_ "Usage: guix discover [OPTION]...
Discover Guix related services using Avahi.\n"))
(display (G_ "
-c, --cache=DIRECTORY cache discovery results in DIRECTORY"))
(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
(list (option '(#\c "cache") #t #f
(lambda (opt name arg result)
(alist-cons 'cache arg result)))
(option '(#\h "help") #f #f
(lambda _
(leave-on-EPIPE (show-help))
(exit 0)))
(option '(#\V "version") #f #f
(lambda _
(show-version-and-exit "guix discover")))))
(define %default-options
`((cache . ,%state-directory)))
;;;
;;; Publish servers.
;;;
(define %publish-services
;; Set of discovered publish services.
(make-hash-table))
(define (publish-file cache-directory)
"Return the name of the file storing the discovered publish services inside
CACHE-DIRECTORY."
(let ((directory (string-append cache-directory "/discover")))
(string-append directory "/publish")))
(define %publish-file
(make-parameter (publish-file %state-directory)))
(define* (write-publish-file #:key (file (%publish-file)))
"Dump the content of %PUBLISH-SERVICES hash table into FILE. Use a write
lock on FILE to synchronize with any potential readers."
(with-atomic-file-output file
(lambda (port)
(hash-for-each
(lambda (name service)
(format port "http://~a:~a~%"
(avahi-service-address service)
(avahi-service-port service)))
%publish-services)))
(chmod file #o644))
(define* (read-substitute-urls #:key (file (%publish-file)))
"Read substitute urls list from FILE and return it. Use a read lock on FILE
to synchronize with the writer."
(if (file-exists? file)
(call-with-input-file file
(lambda (port)
(let loop ((url (read-line port))
(urls '()))
(if (eof-object? url)
urls
(loop (read-line port) (cons url urls))))))
'()))
;;;
;;; Entry point.
;;;
(define %services
;; List of services we want to discover.
(list publish-service-type))
(define (service-proc action service)
(let ((name (avahi-service-name service))
(type (avahi-service-type service)))
(when (string=? type publish-service-type)
(case action
((new-service)
(hash-set! %publish-services name service))
((remove-service)
(hash-remove! %publish-services name)))
(write-publish-file))))
(define-command (guix-discover . args)
(category internal)
(synopsis "discover Guix related services using Avahi")
(with-error-handling
(let* ((opts (parse-command-line args %options (list %default-options)
#:build-options? #f
#:argument-handler
(lambda (arg result)
(leave (G_ "~A: extraneous argument~%") arg))))
(cache (assoc-ref opts 'cache))
(publish-file (publish-file cache)))
(parameterize ((%publish-file publish-file))
(mkdir-p (dirname publish-file))
(false-if-exception (delete-file publish-file))
(catch 'avahi-error
(lambda ()
(avahi-browse-service-thread service-proc
#:types %services))
(lambda (key err function . _)
(cond
((eq? err error/no-daemon)
(warning (G_ "Avahi daemon is not running, \
cannot auto-discover substitutes servers.~%")))
(else
(report-error (G_ "an Avahi error was raised by `~a': ~a~%")
function (error->string err))))
(exit 1)))))))
|
