includes/db/LBFactorySingle.php

   1 <?php
   2 /**
   3  * Simple generator of database connections that always returns the same object.
   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 Database
  22  */
  23
  24 /**
  25  * An LBFactory class that always returns a single database object.
  26  */
  27 class LBFactorySingle extends LBFactory {
  28         /** @var LoadBalancerSingle */
  29         private $lb;
  30
  31         /**
  32          * @param array $conf An associative array with one member:
  33          *  - connection: The DatabaseBase connection object
  34          */
  35         public function __construct( array $conf ) {
  36                 $this->lb = new LoadBalancerSingle( $conf );
  37         }
  38
  39         /**
  40          * @param bool|string $wiki
  41          * @return LoadBalancerSingle
  42          */
  43         public function newMainLB( $wiki = false ) {
  44                 return $this->lb;
  45         }
  46
  47         /**
  48          * @param bool|string $wiki
  49          * @return LoadBalancerSingle
  50          */
  51         public function getMainLB( $wiki = false ) {
  52                 return $this->lb;
  53         }
  54
  55         /**
  56          * @param string $cluster External storage cluster, or false for core
  57          * @param bool|string $wiki Wiki ID, or false for the current wiki
  58          * @return LoadBalancerSingle
  59          */
  60         protected function newExternalLB( $cluster, $wiki = false ) {
  61                 return $this->lb;
  62         }
  63
  64         /**
  65          * @param string $cluster External storage cluster, or false for core
  66          * @param bool|string $wiki Wiki ID, or false for the current wiki
  67          * @return LoadBalancerSingle
  68          */
  69         public function &getExternalLB( $cluster, $wiki = false ) {
  70                 return $this->lb;
  71         }
  72
  73         /**
  74          * @param string|callable $callback
  75          * @param array $params
  76          */
  77         public function forEachLB( $callback, array $params = array() ) {
  78                 call_user_func_array( $callback, array_merge( array( $this->lb ), $params ) );
  79         }
  80 }
  81
  82 /**
  83  * Helper class for LBFactorySingle.
  84  */
  85 class LoadBalancerSingle extends LoadBalancer {
  86         /** @var DatabaseBase */
  87         private $db;
  88
  89         /**
  90          * @param array $params
  91          */
  92         public function __construct( array $params ) {
  93                 $this->db = $params['connection'];
  94                 parent::__construct( array( 'servers' => array( array(
  95                         'type' => $this->db->getType(),
  96                         'host' => $this->db->getServer(),
  97                         'dbname' => $this->db->getDBname(),
  98                         'load' => 1,
  99                 ) ) ) );
 100         }
 101
 102         /**
 103          *
 104          * @param string $server
 105          * @param bool $dbNameOverride
 106          *
 107          * @return DatabaseBase
 108          */
 109         protected function reallyOpenConnection( $server, $dbNameOverride = false ) {
 110                 return $this->db;
 111         }
 112 }