5 * Copyright (C) 2004 Brion Vibber <brion@pobox.com>
6 * https://www.mediawiki.org/
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 * http://www.gnu.org/copyleft/gpl.html
27 use MediaWiki\MediaWikiServices
;
30 * Search engine hook for MySQL 4+
33 class SearchMySQL
extends SearchDatabase
{
34 protected $strictMatching = true;
36 private static $mMinSearchLength;
39 * Parse the user's query and transform it into two SQL fragments:
40 * a WHERE condition and an ORDER BY expression
42 * @param string $filteredText
43 * @param string $fulltext
47 private function parseQuery( $filteredText, $fulltext ) {
48 $lc = $this->legalSearchChars( self
::CHARS_NO_SYNTAX
); // Minus syntax chars (" and *)
50 $this->searchTerms
= [];
52 # @todo FIXME: This doesn't handle parenthetical expressions.
54 if ( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
55 $filteredText, $m, PREG_SET_ORDER
) ) {
56 foreach ( $m as $bits ) {
57 Wikimedia\
suppressWarnings();
58 list( /* all */, $modifier, $term, $nonQuoted, $wildcard ) = $bits;
59 Wikimedia\restoreWarnings
();
61 if ( $nonQuoted != '' ) {
65 $term = str_replace( '"', '', $term );
69 if ( $searchon !== '' ) {
72 if ( $this->strictMatching
&& ( $modifier == '' ) ) {
73 // If we leave this out, boolean op defaults to OR which is rarely helpful.
77 // Some languages such as Serbian store the input form in the search index,
78 // so we may need to search for matches in multiple writing system variants.
79 $contLang = MediaWikiServices
::getInstance()->getContentLanguage();
80 $convertedVariants = $contLang->autoConvertToAllVariants( $term );
81 if ( is_array( $convertedVariants ) ) {
82 $variants = array_unique( array_values( $convertedVariants ) );
84 $variants = [ $term ];
87 // The low-level search index does some processing on input to work
88 // around problems with minimum lengths and encoding in MySQL's
90 // For Chinese this also inserts spaces between adjacent Han characters.
91 $strippedVariants = array_map( [ $contLang, 'normalizeForSearch' ], $variants );
93 // Some languages such as Chinese force all variants to a canonical
94 // form when stripping to the low-level search index, so to be sure
95 // let's check our variants list for unique items after stripping.
96 $strippedVariants = array_unique( $strippedVariants );
98 $searchon .= $modifier;
99 if ( count( $strippedVariants ) > 1 ) {
102 foreach ( $strippedVariants as $stripped ) {
103 $stripped = $this->normalizeText( $stripped );
104 if ( $nonQuoted && strpos( $stripped, ' ' ) !== false ) {
105 // Hack for Chinese: we need to toss in quotes for
106 // multiple-character phrases since normalizeForSearch()
107 // added spaces between them to make word breaks.
108 $stripped = '"' . trim( $stripped ) . '"';
110 $searchon .= "$quote$stripped$quote$wildcard ";
112 if ( count( $strippedVariants ) > 1 ) {
116 // Match individual terms or quoted phrase in result highlighting...
117 // Note that variants will be introduced in a later stage for highlighting!
118 $regexp = $this->regexTerm( $term, $wildcard );
119 $this->searchTerms
[] = $regexp;
121 wfDebug( __METHOD__
. ": Would search with '$searchon'\n" );
122 wfDebug( __METHOD__
. ': Match with /' . implode( '|', $this->searchTerms
) . "/\n" );
124 wfDebug( __METHOD__
. ": Can't understand search query '{$filteredText}'\n" );
127 $dbr = $this->lb
->getConnectionRef( DB_REPLICA
);
128 $searchon = $dbr->addQuotes( $searchon );
129 $field = $this->getIndexField( $fulltext );
131 " MATCH($field) AGAINST($searchon IN BOOLEAN MODE) ",
132 " MATCH($field) AGAINST($searchon IN NATURAL LANGUAGE MODE) DESC "
136 private function regexTerm( $string, $wildcard ) {
137 $regex = preg_quote( $string, '/' );
138 if ( MediaWikiServices
::getInstance()->getContentLanguage()->hasWordBreaks() ) {
140 // Don't cut off the final bit!
143 $regex = "\b$regex\b";
146 // For Chinese, words may legitimately abut other words in the text literal.
147 // Don't add \b boundary checks... note this could cause false positives
153 public function legalSearchChars( $type = self
::CHARS_ALL
) {
154 $searchChars = parent
::legalSearchChars( $type );
155 if ( $type === self
::CHARS_ALL
) {
156 // " for phrase, * for wildcard
157 $searchChars = "\"*" . $searchChars;
163 * Perform a full text search query and return a result set.
165 * @param string $term Raw search term
166 * @return SqlSearchResultSet
168 protected function doSearchTextInDB( $term ) {
169 return $this->searchInternal( $term, true );
173 * Perform a title-only search query and return a result set.
175 * @param string $term Raw search term
176 * @return SqlSearchResultSet
178 protected function doSearchTitleInDB( $term ) {
179 return $this->searchInternal( $term, false );
182 protected function searchInternal( $term, $fulltext ) {
183 // This seems out of place, why is this called with empty term?
184 if ( trim( $term ) === '' ) {
188 $filteredTerm = $this->filter( $term );
189 $query = $this->getQuery( $filteredTerm, $fulltext );
190 $dbr = $this->lb
->getConnectionRef( DB_REPLICA
);
191 $resultSet = $dbr->select(
192 $query['tables'], $query['fields'], $query['conds'],
193 __METHOD__
, $query['options'], $query['joins']
197 $query = $this->getCountQuery( $filteredTerm, $fulltext );
198 $totalResult = $dbr->select(
199 $query['tables'], $query['fields'], $query['conds'],
200 __METHOD__
, $query['options'], $query['joins']
203 $row = $totalResult->fetchObject();
205 $total = intval( $row->c
);
207 $totalResult->free();
209 return new SqlSearchResultSet( $resultSet, $this->searchTerms
, $total );
212 public function supports( $feature ) {
213 switch ( $feature ) {
214 case 'title-suffix-filter':
217 return parent
::supports( $feature );
222 * Add special conditions
223 * @param array &$query
226 protected function queryFeatures( &$query ) {
227 foreach ( $this->features
as $feature => $value ) {
228 if ( $feature === 'title-suffix-filter' && $value ) {
229 $dbr = $this->lb
->getConnectionRef( DB_REPLICA
);
230 $query['conds'][] = 'page_title' . $dbr->buildLike( $dbr->anyString(), $value );
236 * Add namespace conditions
237 * @param array &$query
238 * @since 1.18 (changed)
240 function queryNamespaces( &$query ) {
241 if ( is_array( $this->namespaces
) ) {
242 if ( count( $this->namespaces
) === 0 ) {
243 $this->namespaces
[] = '0';
245 $query['conds']['page_namespace'] = $this->namespaces
;
251 * @param array &$query
254 protected function limitResult( &$query ) {
255 $query['options']['LIMIT'] = $this->limit
;
256 $query['options']['OFFSET'] = $this->offset
;
260 * Construct the SQL query to do the search.
261 * The guts shoulds be constructed in queryMain()
262 * @param string $filteredTerm
263 * @param bool $fulltext
265 * @since 1.18 (changed)
267 private function getQuery( $filteredTerm, $fulltext ) {
276 $this->queryMain( $query, $filteredTerm, $fulltext );
277 $this->queryFeatures( $query );
278 $this->queryNamespaces( $query );
279 $this->limitResult( $query );
285 * Picks which field to index on, depending on what type of query.
286 * @param bool $fulltext
289 private function getIndexField( $fulltext ) {
290 return $fulltext ?
'si_text' : 'si_title';
294 * Get the base part of the search query.
296 * @param array &$query Search query array
297 * @param string $filteredTerm
298 * @param bool $fulltext
299 * @since 1.18 (changed)
301 private function queryMain( &$query, $filteredTerm, $fulltext ) {
302 $match = $this->parseQuery( $filteredTerm, $fulltext );
303 $query['tables'][] = 'page';
304 $query['tables'][] = 'searchindex';
305 $query['fields'][] = 'page_id';
306 $query['fields'][] = 'page_namespace';
307 $query['fields'][] = 'page_title';
308 $query['conds'][] = 'page_id=si_page';
309 $query['conds'][] = $match[0];
310 $query['options']['ORDER BY'] = $match[1];
314 * @since 1.18 (changed)
315 * @param string $filteredTerm
316 * @param bool $fulltext
319 private function getCountQuery( $filteredTerm, $fulltext ) {
320 $match = $this->parseQuery( $filteredTerm, $fulltext );
323 'tables' => [ 'page', 'searchindex' ],
324 'fields' => [ 'COUNT(*) as c' ],
325 'conds' => [ 'page_id=si_page', $match[0] ],
330 $this->queryFeatures( $query );
331 $this->queryNamespaces( $query );
337 * Create or update the search index record for the given page.
338 * Title and text should be pre-processed.
341 * @param string $title
342 * @param string $text
344 function update( $id, $title, $text ) {
345 $dbw = $this->lb
->getConnectionRef( DB_MASTER
);
346 $dbw->replace( 'searchindex',
350 'si_title' => $this->normalizeText( $title ),
351 'si_text' => $this->normalizeText( $text )
356 * Update a search index record's title only.
357 * Title should be pre-processed.
360 * @param string $title
362 function updateTitle( $id, $title ) {
363 $dbw = $this->lb
->getConnectionRef( DB_MASTER
);
364 $dbw->update( 'searchindex',
365 [ 'si_title' => $this->normalizeText( $title ) ],
366 [ 'si_page' => $id ],
372 * Delete an indexed page
373 * Title should be pre-processed.
375 * @param int $id Page id that was deleted
376 * @param string $title Title of page that was deleted
378 function delete( $id, $title ) {
379 $dbw = $this->lb
->getConnectionRef( DB_MASTER
);
380 $dbw->delete( 'searchindex', [ 'si_page' => $id ], __METHOD__
);
384 * Converts some characters for MySQL's indexing to grok it correctly,
385 * and pads short words to overcome limitations.
386 * @param string $string
387 * @return mixed|string
389 function normalizeText( $string ) {
390 $out = parent
::normalizeText( $string );
392 // MySQL fulltext index doesn't grok utf-8, so we
393 // need to fold cases and convert to hex
394 $out = preg_replace_callback(
395 "/([\\xc0-\\xff][\\x80-\\xbf]*)/",
396 [ $this, 'stripForSearchCallback' ],
397 MediaWikiServices
::getInstance()->getContentLanguage()->lc( $out ) );
399 // And to add insult to injury, the default indexing
400 // ignores short words... Pad them so we can pass them
401 // through without reconfiguring the server...
402 $minLength = $this->minSearchLength();
403 if ( $minLength > 1 ) {
411 // Periods within things like hostnames and IP addresses
412 // are also important -- we want a search for "example.com"
413 // or "192.168.1.1" to work sanely.
414 // MySQL's search seems to ignore them, so you'd match on
415 // "example.wikipedia.com" and "192.168.83.1" as well.
425 * Armor a case-folded UTF-8 string to get through MySQL's
426 * fulltext search without being mucked up by funny charset
427 * settings or anything else of the sort.
428 * @param array $matches
431 protected function stripForSearchCallback( $matches ) {
432 return 'u8' . bin2hex( $matches[1] );
436 * Check MySQL server's ft_min_word_len setting so we know
437 * if we need to pad short words...
441 protected function minSearchLength() {
442 if ( is_null( self
::$mMinSearchLength ) ) {
443 $sql = "SHOW GLOBAL VARIABLES LIKE 'ft\\_min\\_word\\_len'";
445 $dbr = $this->lb
->getConnectionRef( DB_REPLICA
);
446 $result = $dbr->query( $sql, __METHOD__
);
447 $row = $result->fetchObject();
450 if ( $row && $row->Variable_name
== 'ft_min_word_len' ) {
451 self
::$mMinSearchLength = intval( $row->Value
);
453 self
::$mMinSearchLength = 0;
456 return self
::$mMinSearchLength;