3 * Database search engine
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
24 use Wikimedia\Rdbms\IDatabase
;
27 * Base search engine base class for database-backed searches
31 abstract class SearchDatabase
extends SearchEngine
{
33 * @var IDatabase Replica database from which to read results
38 * @param IDatabase|null $db The database to search from
40 public function __construct( IDatabase
$db = null ) {
41 $this->db
= $db ?
: wfGetDB( DB_REPLICA
);
46 * @return SearchResultSet|Status|null
48 final public function doSearchText( $term ) {
49 return $this->doSearchTextInDB( $this->extractNamespacePrefix( $term ) );
53 * Perform a full text search query and return a result set.
55 * @param string $term Raw search term
56 * @return SqlSearchResultSet
58 abstract protected function doSearchTextInDB( $term );
62 * @return SearchResultSet|null
64 final public function doSearchTitle( $term ) {
65 return $this->doSearchTitleInDB( $this->extractNamespacePrefix( $term ) );
69 * Perform a title-only search query and return a result set.
71 * @param string $term Raw search term
72 * @return SqlSearchResultSet
74 abstract protected function doSearchTitleInDB( $term );
77 * Return a 'cleaned up' search string
82 protected function filter( $text ) {
83 // List of chars allowed in the search query.
84 // This must include chars used in the search syntax.
85 // Usually " (phrase) or * (wildcards) if supported by the engine
86 $lc = $this->legalSearchChars( self
::CHARS_ALL
);
87 return trim( preg_replace( "/[^{$lc}]/", " ", $text ) );
91 * Extract the optional namespace prefix and set self::namespaces
92 * accordingly and return the query string
94 * @return string the query string without any namespace prefix
96 final protected function extractNamespacePrefix( $term ) {
97 $queryAndNs = self
::parseNamespacePrefixes( $term );
98 if ( $queryAndNs === false ) {
101 $this->namespaces
= $queryAndNs[1];
102 return $queryAndNs[0];