includes/db/loadbalancer/LBFactorySimple.php

   1 <?php
   2 /**
   3  * Generator of database load balancing objects.
   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  * A simple single-master LBFactory that gets its configuration from the b/c globals
  26  */
  27 class LBFactorySimple extends LBFactory {
  28         /** @var LoadBalancer */
  29         private $mainLB;
  30         /** @var LoadBalancer[] */
  31         private $extLBs = [];
  32
  33         /** @var string */
  34         private $loadMonitorClass;
  35
  36         public function __construct( array $conf ) {
  37                 parent::__construct( $conf );
  38
  39                 $this->loadMonitorClass = isset( $conf['loadMonitorClass'] )
  40                         ? $conf['loadMonitorClass']
  41                         : null;
  42         }
  43
  44         /**
  45          * @param bool|string $wiki
  46          * @return LoadBalancer
  47          */
  48         public function newMainLB( $wiki = false ) {
  49                 global $wgDBservers, $wgDBprefix, $wgDBmwschema;
  50
  51                 if ( is_array( $wgDBservers ) ) {
  52                         $servers = $wgDBservers;
  53                         foreach ( $servers as $i => &$server ) {
  54                                 if ( $i == 0 ) {
  55                                         $server['master'] = true;
  56                                 } else {
  57                                         $server['replica'] = true;
  58                                 }
  59                                 $server += [
  60                                         'schema' => $wgDBmwschema,
  61                                         'tablePrefix' => $wgDBprefix,
  62                                         'flags' => DBO_DEFAULT
  63                                 ];
  64                         }
  65                 } else {
  66                         global $wgDBserver, $wgDBuser, $wgDBpassword, $wgDBname, $wgDBtype, $wgDebugDumpSql;
  67                         global $wgDBssl, $wgDBcompress;
  68
  69                         $flags = DBO_DEFAULT;
  70                         if ( $wgDebugDumpSql ) {
  71                                 $flags |= DBO_DEBUG;
  72                         }
  73                         if ( $wgDBssl ) {
  74                                 $flags |= DBO_SSL;
  75                         }
  76                         if ( $wgDBcompress ) {
  77                                 $flags |= DBO_COMPRESS;
  78                         }
  79
  80                         $servers = [ [
  81                                 'host' => $wgDBserver,
  82                                 'user' => $wgDBuser,
  83                                 'password' => $wgDBpassword,
  84                                 'dbname' => $wgDBname,
  85                                 'schema' => $wgDBmwschema,
  86                                 'tablePrefix' => $wgDBprefix,
  87                                 'type' => $wgDBtype,
  88                                 'load' => 1,
  89                                 'flags' => $flags,
  90                                 'master' => true
  91                         ] ];
  92                 }
  93
  94                 return $this->newLoadBalancer( $servers );
  95         }
  96
  97         /**
  98          * @param bool|string $wiki
  99          * @return LoadBalancer
 100          */
 101         public function getMainLB( $wiki = false ) {
 102                 if ( !isset( $this->mainLB ) ) {
 103                         $this->mainLB = $this->newMainLB( $wiki );
 104                         $this->chronProt->initLB( $this->mainLB );
 105                 }
 106
 107                 return $this->mainLB;
 108         }
 109
 110         /**
 111          * @param string $cluster
 112          * @param bool|string $wiki
 113          * @return LoadBalancer
 114          * @throws InvalidArgumentException
 115          */
 116         protected function newExternalLB( $cluster, $wiki = false ) {
 117                 global $wgExternalServers;
 118                 if ( !isset( $wgExternalServers[$cluster] ) ) {
 119                         throw new InvalidArgumentException( __METHOD__ . ": Unknown cluster \"$cluster\"" );
 120                 }
 121
 122                 return $this->newLoadBalancer( $wgExternalServers[$cluster] );
 123         }
 124
 125         /**
 126          * @param string $cluster
 127          * @param bool|string $wiki
 128          * @return array
 129          */
 130         public function getExternalLB( $cluster, $wiki = false ) {
 131                 if ( !isset( $this->extLBs[$cluster] ) ) {
 132                         $this->extLBs[$cluster] = $this->newExternalLB( $cluster, $wiki );
 133                         $this->chronProt->initLB( $this->extLBs[$cluster] );
 134                 }
 135
 136                 return $this->extLBs[$cluster];
 137         }
 138
 139         private function newLoadBalancer( array $servers ) {
 140                 $lb = new LoadBalancer( array_merge(
 141                         $this->baseLoadBalancerParams(),
 142                         [
 143                                 'servers' => $servers,
 144                                 'loadMonitor' => $this->loadMonitorClass,
 145                         ]
 146                 ) );
 147                 $this->initLoadBalancer( $lb );
 148
 149                 return $lb;
 150         }
 151
 152         /**
 153          * Execute a function for each tracked load balancer
 154          * The callback is called with the load balancer as the first parameter,
 155          * and $params passed as the subsequent parameters.
 156          *
 157          * @param callable $callback
 158          * @param array $params
 159          */
 160         public function forEachLB( $callback, array $params = [] ) {
 161                 if ( isset( $this->mainLB ) ) {
 162                         call_user_func_array( $callback, array_merge( [ $this->mainLB ], $params ) );
 163                 }
 164                 foreach ( $this->extLBs as $lb ) {
 165                         call_user_func_array( $callback, array_merge( [ $lb ], $params ) );
 166                 }
 167         }
 168 }