/includes/search/SearchSqlite.php
PHP | 344 lines | 270 code | 15 blank | 59 comment | 14 complexity | 1b09de88073273cb383cbecb3e15f3d2 MD5 | raw file
Possible License(s): GPL-2.0, Apache-2.0, LGPL-3.0
- <?php
- /**
- * SQLite search backend, based upon SearchMysql
- *
- * This program 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.
- *
- * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
- * http://www.gnu.org/copyleft/gpl.html
- *
- * @file
- * @ingroup Search
- */
- /**
- * Search engine hook for SQLite
- * @ingroup Search
- */
- class SearchSqlite extends SearchEngine {
- /**
- * @var DatabaseSqlite
- */
- protected $db;
- /**
- * Creates an instance of this class
- * @param $db DatabaseSqlite: database object
- */
- function __construct( $db ) {
- parent::__construct( $db );
- }
- /**
- * Whether fulltext search is supported by current schema
- * @return Boolean
- */
- function fulltextSearchSupported() {
- return $this->db->checkForEnabledSearch();
- }
- /**
- * Parse the user's query and transform it into an SQL fragment which will
- * become part of a WHERE clause
- *
- * @return string
- */
- function parseQuery( $filteredText, $fulltext ) {
- global $wgContLang;
- $lc = SearchEngine::legalSearchChars(); // Minus format chars
- $searchon = '';
- $this->searchTerms = array();
- $m = array();
- if( preg_match_all( '/([-+<>~]?)(([' . $lc . ']+)(\*?)|"[^"]*")/',
- $filteredText, $m, PREG_SET_ORDER ) ) {
- foreach( $m as $bits ) {
- @list( /* all */, $modifier, $term, $nonQuoted, $wildcard ) = $bits;
- if( $nonQuoted != '' ) {
- $term = $nonQuoted;
- $quote = '';
- } else {
- $term = str_replace( '"', '', $term );
- $quote = '"';
- }
- if( $searchon !== '' ) {
- $searchon .= ' ';
- }
- // Some languages such as Serbian store the input form in the search index,
- // so we may need to search for matches in multiple writing system variants.
- $convertedVariants = $wgContLang->autoConvertToAllVariants( $term );
- if( is_array( $convertedVariants ) ) {
- $variants = array_unique( array_values( $convertedVariants ) );
- } else {
- $variants = array( $term );
- }
- // The low-level search index does some processing on input to work
- // around problems with minimum lengths and encoding in MySQL's
- // fulltext engine.
- // For Chinese this also inserts spaces between adjacent Han characters.
- $strippedVariants = array_map(
- array( $wgContLang, 'normalizeForSearch' ),
- $variants );
- // Some languages such as Chinese force all variants to a canonical
- // form when stripping to the low-level search index, so to be sure
- // let's check our variants list for unique items after stripping.
- $strippedVariants = array_unique( $strippedVariants );
- $searchon .= $modifier;
- if( count( $strippedVariants) > 1 )
- $searchon .= '(';
- foreach( $strippedVariants as $stripped ) {
- if( $nonQuoted && strpos( $stripped, ' ' ) !== false ) {
- // Hack for Chinese: we need to toss in quotes for
- // multiple-character phrases since normalizeForSearch()
- // added spaces between them to make word breaks.
- $stripped = '"' . trim( $stripped ) . '"';
- }
- $searchon .= "$quote$stripped$quote$wildcard ";
- }
- if( count( $strippedVariants) > 1 )
- $searchon .= ')';
- // Match individual terms or quoted phrase in result highlighting...
- // Note that variants will be introduced in a later stage for highlighting!
- $regexp = $this->regexTerm( $term, $wildcard );
- $this->searchTerms[] = $regexp;
- }
- } else {
- wfDebug( __METHOD__ . ": Can't understand search query '{$filteredText}'\n" );
- }
- $searchon = $this->db->strencode( $searchon );
- $field = $this->getIndexField( $fulltext );
- return " $field MATCH '$searchon' ";
- }
- function regexTerm( $string, $wildcard ) {
- global $wgContLang;
- $regex = preg_quote( $string, '/' );
- if( $wgContLang->hasWordBreaks() ) {
- if( $wildcard ) {
- // Don't cut off the final bit!
- $regex = "\b$regex";
- } else {
- $regex = "\b$regex\b";
- }
- } else {
- // For Chinese, words may legitimately abut other words in the text literal.
- // Don't add \b boundary checks... note this could cause false positives
- // for latin chars.
- }
- return $regex;
- }
- public static function legalSearchChars() {
- return "\"*" . parent::legalSearchChars();
- }
- /**
- * Perform a full text search query and return a result set.
- *
- * @param $term String: raw search term
- * @return SqliteSearchResultSet
- */
- function searchText( $term ) {
- return $this->searchInternal( $term, true );
- }
- /**
- * Perform a title-only search query and return a result set.
- *
- * @param $term String: raw search term
- * @return SqliteSearchResultSet
- */
- function searchTitle( $term ) {
- return $this->searchInternal( $term, false );
- }
- protected function searchInternal( $term, $fulltext ) {
- global $wgCountTotalSearchHits, $wgContLang;
- if ( !$this->fulltextSearchSupported() ) {
- return null;
- }
- $filteredTerm = $this->filter( $wgContLang->lc( $term ) );
- $resultSet = $this->db->query( $this->getQuery( $filteredTerm, $fulltext ) );
- $total = null;
- if( $wgCountTotalSearchHits ) {
- $totalResult = $this->db->query( $this->getCountQuery( $filteredTerm, $fulltext ) );
- $row = $totalResult->fetchObject();
- if( $row ) {
- $total = intval( $row->c );
- }
- $totalResult->free();
- }
- return new SqliteSearchResultSet( $resultSet, $this->searchTerms, $total );
- }
- /**
- * Return a partial WHERE clause to exclude redirects, if so set
- * @return String
- */
- function queryRedirect() {
- if( $this->showRedirects ) {
- return '';
- } else {
- return 'AND page_is_redirect=0';
- }
- }
- /**
- * Return a partial WHERE clause to limit the search to the given namespaces
- * @return String
- */
- function queryNamespaces() {
- if( is_null($this->namespaces) )
- return ''; # search all
- if ( !count( $this->namespaces ) ) {
- $namespaces = '0';
- } else {
- $namespaces = $this->db->makeList( $this->namespaces );
- }
- return 'AND page_namespace IN (' . $namespaces . ')';
- }
- /**
- * Returns a query with limit for number of results set.
- * @param $sql String:
- * @return String
- */
- function limitResult( $sql ) {
- return $this->db->limitResult( $sql, $this->limit, $this->offset );
- }
- /**
- * Construct the full SQL query to do the search.
- * The guts shoulds be constructed in queryMain()
- * @param $filteredTerm String
- * @param $fulltext Boolean
- */
- function getQuery( $filteredTerm, $fulltext ) {
- return $this->limitResult(
- $this->queryMain( $filteredTerm, $fulltext ) . ' ' .
- $this->queryRedirect() . ' ' .
- $this->queryNamespaces()
- );
- }
- /**
- * Picks which field to index on, depending on what type of query.
- * @param $fulltext Boolean
- * @return String
- */
- function getIndexField( $fulltext ) {
- return $fulltext ? 'si_text' : 'si_title';
- }
- /**
- * Get the base part of the search query.
- *
- * @param $filteredTerm String
- * @param $fulltext Boolean
- * @return String
- */
- function queryMain( $filteredTerm, $fulltext ) {
- $match = $this->parseQuery( $filteredTerm, $fulltext );
- $page = $this->db->tableName( 'page' );
- $searchindex = $this->db->tableName( 'searchindex' );
- return "SELECT $searchindex.rowid, page_namespace, page_title " .
- "FROM $page,$searchindex " .
- "WHERE page_id=$searchindex.rowid AND $match";
- }
- function getCountQuery( $filteredTerm, $fulltext ) {
- $match = $this->parseQuery( $filteredTerm, $fulltext );
- $page = $this->db->tableName( 'page' );
- $searchindex = $this->db->tableName( 'searchindex' );
- return "SELECT COUNT(*) AS c " .
- "FROM $page,$searchindex " .
- "WHERE page_id=$searchindex.rowid AND $match" .
- $this->queryRedirect() . ' ' .
- $this->queryNamespaces();
- }
- /**
- * Create or update the search index record for the given page.
- * Title and text should be pre-processed.
- *
- * @param $id Integer
- * @param $title String
- * @param $text String
- */
- function update( $id, $title, $text ) {
- if ( !$this->fulltextSearchSupported() ) {
- return;
- }
- // @todo: find a method to do it in a single request,
- // couldn't do it so far due to typelessness of FTS3 tables.
- $dbw = wfGetDB( DB_MASTER );
- $dbw->delete( 'searchindex', array( 'rowid' => $id ), __METHOD__ );
- $dbw->insert( 'searchindex',
- array(
- 'rowid' => $id,
- 'si_title' => $title,
- 'si_text' => $text
- ), __METHOD__ );
- }
- /**
- * Update a search index record's title only.
- * Title should be pre-processed.
- *
- * @param $id Integer
- * @param $title String
- */
- function updateTitle( $id, $title ) {
- if ( !$this->fulltextSearchSupported() ) {
- return;
- }
- $dbw = wfGetDB( DB_MASTER );
- $dbw->update( 'searchindex',
- array( 'si_title' => $title ),
- array( 'rowid' => $id ),
- __METHOD__ );
- }
- }
- /**
- * @ingroup Search
- */
- class SqliteSearchResultSet extends SqlSearchResultSet {
- function __construct( $resultSet, $terms, $totalHits=null ) {
- parent::__construct( $resultSet, $terms );
- $this->mTotalHits = $totalHits;
- }
- function getTotalHits() {
- return $this->mTotalHits;
- }
- }