includes/dao/DBAccessBase.php

   1 <?php
   2
   3 /**
   4  * Base class for objects that allow access to other wiki's databases using
   5  * the foreign database access mechanism implemented by LBFactoryMulti.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @since 1.21
  23  *
  24  * @file
  25  * @ingroup Database
  26  *
  27  * @licence GNU GPL v2+
  28  * @author Daniel Kinzler
  29  */
  30 abstract class DBAccessBase implements IDBAccessObject {
  31         /**
  32          * @var string|bool $wiki The target wiki's name. This must be an ID
  33          * that LBFactory can understand.
  34          */
  35         protected $wiki = false;
  36
  37         /**
  38          * @param string|bool $wiki The target wiki's name. This must be an ID
  39          * that LBFactory can understand.
  40          */
  41         public function __construct( $wiki = false ) {
  42                 $this->wiki = $wiki;
  43         }
  44
  45         /**
  46          * Returns a database connection.
  47          *
  48          * @see wfGetDB()
  49          * @see LoadBalancer::getConnection()
  50          *
  51          * @since 1.21
  52          *
  53          * @param int $id Which connection to use
  54          * @param array $groups Query groups
  55          *
  56          * @return DatabaseBase
  57          */
  58         protected function getConnection( $id, $groups = array() ) {
  59                 $loadBalancer = wfGetLB( $this->wiki );
  60
  61                 return $loadBalancer->getConnection( $id, $groups, $this->wiki );
  62         }
  63
  64         /**
  65          * Releases a database connection and makes it available for recycling.
  66          *
  67          * @see LoadBalancer::reuseConnection()
  68          *
  69          * @since 1.21
  70          *
  71          * @param DatabaseBase $db The database connection to release.
  72          */
  73         protected function releaseConnection( DatabaseBase $db ) {
  74                 if ( $this->wiki !== false ) {
  75                         $loadBalancer = $this->getLoadBalancer();
  76                         $loadBalancer->reuseConnection( $db );
  77                 }
  78         }
  79
  80         /**
  81          * Get the database type used for read operations.
  82          *
  83          * @see wfGetLB
  84          *
  85          * @since 1.21
  86          *
  87          * @return LoadBalancer The database load balancer object
  88          */
  89         public function getLoadBalancer() {
  90                 return wfGetLB( $this->wiki );
  91         }
  92 }