includes/search/SearchDatabase.php

   1 <?php
   2 /**
   3  * Database search engine
   4  *
   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.
   9  *
  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.
  14  *
  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
  19  *
  20  * @file
  21  * @ingroup Search
  22  */
  23
  24 use MediaWiki\Status\Status;
  25 use Wikimedia\Rdbms\DBQueryError;
  26 use Wikimedia\Rdbms\IConnectionProvider;
  27
  28 /**
  29  * Base search engine base class for database-backed searches
  30  * @stable to extend
  31  * @ingroup Search
  32  * @since 1.23
  33  */
  34 abstract class SearchDatabase extends SearchEngine {
  35         /**
  36          * @var string[] search terms
  37          */
  38         protected $searchTerms = [];
  39         protected IConnectionProvider $dbProvider;
  40
  41         /**
  42          * @param IConnectionProvider $dbProvider
  43          */
  44         public function __construct( IConnectionProvider $dbProvider ) {
  45                 $this->dbProvider = $dbProvider;
  46         }
  47
  48         /**
  49          * @param string $term
  50          * @return ISearchResultSet|Status|null
  51          */
  52         final public function doSearchText( $term ) {
  53                 return $this->doSearchTextInDB( $this->extractNamespacePrefix( $term ) );
  54         }
  55
  56         /**
  57          * Perform a full text search query and return a result set.
  58          *
  59          * @param string $term Raw search term
  60          * @return SqlSearchResultSet|null
  61          */
  62         abstract protected function doSearchTextInDB( $term );
  63
  64         /**
  65          * @param string $term
  66          * @return ISearchResultSet|null
  67          */
  68         final public function doSearchTitle( $term ) {
  69                 try {
  70                         return $this->doSearchTitleInDB( $this->extractNamespacePrefix( $term ) );
  71                 } catch ( DBQueryError $dqe ) {
  72                         if ( $dqe->errno == 1064 ) {
  73                                 throw new DBQueryError(
  74                                         $dqe->db,
  75                                         "Query incompatible with database engine. For more information: " .
  76                                         "https://bugs.mysql.com/bug.php?id=78485 https://jira.mariadb.org/browse/MDEV-21750 / " .
  77                                         "https://phabricator.wikimedia.org/T355096",
  78                                         1064, $dqe->sql, __METHOD__
  79                                         );
  80                         } else {
  81                                 throw $dqe;
  82                         }
  83                 }
  84         }
  85
  86         /**
  87          * Perform a title-only search query and return a result set.
  88          *
  89          * @param string $term Raw search term
  90          * @return SqlSearchResultSet|null
  91          */
  92         abstract protected function doSearchTitleInDB( $term );
  93
  94         /**
  95          * Return a 'cleaned up' search string
  96          *
  97          * @param string $text
  98          * @return string
  99          */
 100         protected function filter( $text ) {
 101                 // List of chars allowed in the search query.
 102                 // This must include chars used in the search syntax.
 103                 // Usually " (phrase) or * (wildcards) if supported by the engine
 104                 $lc = $this->legalSearchChars( self::CHARS_ALL );
 105                 return trim( preg_replace( "/[^{$lc}]/", " ", $text ) );
 106         }
 107
 108         /**
 109          * Extract the optional namespace prefix and set self::namespaces
 110          * accordingly and return the query string
 111          * @param string $term
 112          * @return string the query string without any namespace prefix
 113          */
 114         final protected function extractNamespacePrefix( $term ) {
 115                 $queryAndNs = self::parseNamespacePrefixes( $term );
 116                 if ( $queryAndNs === false ) {
 117                         return $term;
 118                 }
 119                 $this->namespaces = $queryAndNs[1];
 120                 return $queryAndNs[0];
 121         }
 122 }