summaryrefslogtreecommitdiff
path: root/guix/scripts/system/search.scm
blob: b4f790c9bf567197bc23b82a0b8828656abdbbc9 (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
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017 Ludovic Courtès <ludo@gnu.org>
;;;
;;; 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 system search)
  #:use-module (guix ui)
  #:use-module (guix utils)
  #:use-module (gnu services)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-11)
  #:use-module (srfi srfi-26)
  #:use-module (ice-9 regex)
  #:use-module (ice-9 match)
  #:export (service-type->recutils
            find-service-types
            guix-system-search))

;;; Commentary:
;;;
;;; Implement the 'guix system search' command, which searches among the
;;; available service types.
;;;
;;; Code:

(define service-type-name*
  (compose symbol->string service-type-name))

(define* (service-type->recutils type port
                                 #:optional (width (%text-width))
                                 #:key (extra-fields '()))
  "Write to PORT a recutils record of TYPE, arranging to fit within WIDTH
columns."
  (define width*
    ;; The available number of columns once we've taken into account space for
    ;; the initial "+ " prefix.
    (if (> width 2) (- width 2) width))

  (define (extensions->recutils extensions)
    (let ((list (string-join (map (compose service-type-name*
                                           service-extension-target)
                                  extensions))))
      (string->recutils
       (fill-paragraph list width*
                       (string-length "extends: ")))))

  ;; Note: Don't i18n field names so that people can post-process it.
  (format port "name: ~a~%" (service-type-name type))
  (format port "location: ~a~%"
          (or (and=> (service-type-location type) location->string)
              (G_ "unknown")))

  (format port "extends: ~a~%"
          (extensions->recutils (service-type-extensions type)))

  (when (service-type-description type)
    (format port "~a~%"
            (string->recutils
             (string-trim-right
              (parameterize ((%text-width width*))
                (texi->plain-text
                 (string-append "description: "
                                (or (and=> (service-type-description type) P_)
                                    ""))))
              #\newline))))

  (for-each (match-lambda
              ((field . value)
               (let ((field (symbol->string field)))
                 (format port "~a: ~a~%"
                         field
                         (fill-paragraph (object->string value) width*
                                         (string-length field))))))
            extra-fields)
  (newline port))

(define (service-type-description-string type)
  "Return the rendered and localised description of TYPE, a service type."
  (and=> (service-type-description type)
         (compose texi->plain-text P_)))

(define %service-type-metrics
  ;; Metrics used to estimate the relevance of a search result.
  `((,service-type-name* . 3)
    (,service-type-description-string . 2)
    (,(lambda (type)
        (match (and=> (service-type-location type) location-file)
          ((? string? file)
           (basename file ".scm"))
          (#f
           "")))
     . 1)))

(define (find-service-types regexps)
  "Return two values: the list of service types whose name or description
matches at least one of REGEXPS sorted by relevance, and the list of relevance
scores."
  (let ((matches (fold-service-types
                  (lambda (type result)
                    (match (relevance type regexps
                                      %service-type-metrics)
                      ((? zero?)
                       result)
                      (score
                       (cons (list type score) result))))
                  '())))
    (unzip2 (sort matches
                  (lambda (m1 m2)
                    (match m1
                      ((type1 score1)
                       (match m2
                         ((type2 score2)
                          (if (= score1 score2)
                              (string>? (service-type-name* type1)
                                        (service-type-name* type2))
                              (> score1 score2)))))))))))


(define (guix-system-search . args)
  (with-error-handling
    (let ((regexps (map (cut make-regexp* <> regexp/icase) args)))
      (leave-on-EPIPE
       (let-values (((services scores)
                     (find-service-types regexps)))
         (for-each (lambda (service score)
                     (service-type->recutils service
                                             (current-output-port)
                                             #:extra-fields
                                             `((relevance . ,score))))
                   services
                   scores))))))