blob: 92bf5d37e712f4358146bb6509dbe314e3f46778 (
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
|
;;; guile-xapian --- Guile bindings for Xapian
;;; Copyright © 2020 Arun Isaac <arunisaac@systemreboot.net>
;;;
;;; This file is part of guile-xapian.
;;;
;;; guile-xapian 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 2 of the
;;; License, or (at your option) any later version.
;;;
;;; guile-xapian 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 guile-xapian. If not, see
;;; <https://www.gnu.org/licenses/>.
(define-module (xapian xapian)
#:use-module (rnrs arithmetic bitwise)
#:use-module (ice-9 match)
#:use-module (srfi srfi-26)
#:use-module (xapian wrap)
#:export (xapian-open
xapian-close
call-with-database
database-document-count
xapian-open-writable
xapian-close-writable
call-with-writable-database
add-document!
replace-document!
make-document
document-data
document-slot-ref
make-stem
make-term-generator
index-text!
increase-termpos!
parse-query
enquire
enquire-mset
mset-item-docid
mset-item-document
mset-item-rank
mset-item-weight
mset-fold
mset-snippet))
(define xapian-open new-Database)
(define xapian-close delete-Database)
(define (call-with-database dbpath proc)
(let ((db (xapian-open dbpath)))
(dynamic-wind noop (cut proc db) (cut xapian-close db))))
(define database-document-count Database-get-doccount)
(define xapian-open-writable new-WritableDatabase)
(define xapian-close-writable delete-WritableDatabase)
(define (call-with-writable-database dbpath proc)
(let ((db (xapian-open-writable dbpath)))
(dynamic-wind noop (cut proc db) (cut xapian-close-writable db))))
(define add-document! WritableDatabase-add-document)
(define replace-document! WritableDatabase-replace-document)
(define* (make-document #:key data (terms '()) (values '()))
(let ((doc (new-Document)))
(when data
(Document-set-data doc data))
(for-each (match-lambda
((term . wdf-increment)
(Document-add-term doc term wdf-increment)))
terms)
(for-each (match-lambda
((slot . value)
(Document-add-value doc slot value)))
values)
doc))
(define document-data Document-get-data)
(define document-slot-ref Document-get-value)
(define make-stem new-Stem)
(define* (make-term-generator #:key stem document)
(let ((term-generator (new-TermGenerator)))
(TermGenerator-set-stemmer term-generator stem)
(TermGenerator-set-document term-generator document)
term-generator))
(define* (index-text! term-generator text #:key (wdf-increment 1) prefix)
(apply TermGenerator-index-text term-generator text wdf-increment
(if prefix (list prefix) '())))
(define increase-termpos! TermGenerator-increase-termpos)
(define* (parse-query querystring #:key stemmer stemming-strategy (prefixes '()))
(let ((queryparser (new-QueryParser)))
(QueryParser-set-stemmer queryparser stemmer)
(when stemming-strategy
(QueryParser-set-stemming-strategy queryparser stemming-strategy))
(for-each (match-lambda
((field . prefix)
(QueryParser-add-prefix queryparser field prefix)))
prefixes)
(let ((query (QueryParser-parse-query queryparser querystring)))
(delete-QueryParser queryparser)
query)))
(define* (enquire db query #:key weighting-scheme)
(let ((enquire (new-Enquire db)))
(Enquire-set-query enquire query)
(when weighting-scheme
(Enquire-set-weighting-scheme enquire weighting-scheme))
enquire))
(define* (enquire-mset enquire #:key (offset 0) maximum-items)
"Run a query using the settings in the ENQUIRE object and return an
mset object.
OFFSET specifies the number of items to ignore at the beginning of the
result set.
MAXIMUM-ITEMS specifies the maximum number of items to return. To
return all matches, pass the result of calling database-document-count
on the database object."
(Enquire-get-mset enquire offset maximum-items))
(define mset-item-docid MSetIterator-get-docid)
(define mset-item-document MSetIterator-get-document)
(define mset-item-rank MSetIterator-get-rank)
(define mset-item-weight MSetIterator-get-weight)
(define (mset-fold proc init mset)
(let loop ((head (MSet-begin mset))
(result init))
(cond
((MSetIterator-equals head (MSet-end mset)) result)
(else (let ((result (proc head result)))
(MSetIterator-next head)
(loop head result))))))
(define (get-flag flag-thunk value)
(if value (flag-thunk) 0))
;; TODO: Support cjk-words?
(define* (mset-snippet mset text
#:key (length 500) (stemmer (make-stem "none"))
(highlight-start "<b>") (highlight-end "</b>") (omit "...")
(background-model? #t) (exhaustive? #t)
(empty-without-match? #t)
(cjk-ngram? #t))
(MSet-snippet mset text length stemmer
(bitwise-ior (get-flag MSet-SNIPPET-BACKGROUND-MODEL background-model?)
(get-flag MSet-SNIPPET-EXHAUSTIVE exhaustive?)
(get-flag MSet-SNIPPET-EMPTY-WITHOUT-MATCH empty-without-match?)
(get-flag MSet-SNIPPET-CJK-NGRAM cjk-ngram?))
highlight-start highlight-end omit))
|
