includes/libs/rdbms/lbfactory/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 namespace Wikimedia\Rdbms;
  25
  26 use LoadBalancerSingle;
  27 use IDatabase;
  28 use InvalidArgumentException;
  29 use BadMethodCallException;
  30
  31 /**
  32  * An LBFactory class that always returns a single database object.
  33  */
  34 class LBFactorySingle extends LBFactory {
  35         /** @var LoadBalancerSingle */
  36         private $lb;
  37
  38         /**
  39          * @param array $conf An associative array with one member:
  40          *  - connection: The IDatabase connection object
  41          */
  42         public function __construct( array $conf ) {
  43                 parent::__construct( $conf );
  44
  45                 if ( !isset( $conf['connection'] ) ) {
  46                         throw new InvalidArgumentException( "Missing 'connection' argument." );
  47                 }
  48
  49                 $lb = new LoadBalancerSingle( array_merge( $this->baseLoadBalancerParams(), $conf ) );
  50                 $this->initLoadBalancer( $lb );
  51                 $this->lb = $lb;
  52         }
  53
  54         /**
  55          * @param IDatabase $db Live connection handle
  56          * @param array $params Parameter map to LBFactorySingle::__constructs()
  57          * @return LBFactorySingle
  58          * @since 1.28
  59          */
  60         public static function newFromConnection( IDatabase $db, array $params = [] ) {
  61                 return new static( [ 'connection' => $db ] + $params );
  62         }
  63
  64         /**
  65          * @param bool|string $domain (unused)
  66          * @return LoadBalancerSingle
  67          */
  68         public function newMainLB( $domain = false ) {
  69                 return $this->lb;
  70         }
  71
  72         /**
  73          * @param bool|string $domain (unused)
  74          * @return LoadBalancerSingle
  75          */
  76         public function getMainLB( $domain = false ) {
  77                 return $this->lb;
  78         }
  79
  80         public function newExternalLB( $cluster ) {
  81                 throw new BadMethodCallException( "Method is not supported." );
  82         }
  83
  84         public function getExternalLB( $cluster ) {
  85                 throw new BadMethodCallException( "Method is not supported." );
  86         }
  87
  88         /**
  89          * @return LoadBalancerSingle[] Map of (cluster name => LoadBalancer)
  90          */
  91         public function getAllMainLBs() {
  92                 return [ 'DEFAULT' => $this->lb ];
  93         }
  94
  95         /**
  96          * @return LoadBalancerSingle[] Map of (cluster name => LoadBalancer)
  97          */
  98         public function getAllExternalLBs() {
  99                 return [];
 100         }
 101
 102         /**
 103          * @param string|callable $callback
 104          * @param array $params
 105          */
 106         public function forEachLB( $callback, array $params = [] ) {
 107                 call_user_func_array( $callback, array_merge( [ $this->lb ], $params ) );
 108         }
 109 }