includes/db/loadbalancer/LBFactoryMW.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 use MediaWiki\MediaWikiServices;
  25 use MediaWiki\Services\DestructibleService;
  26 use MediaWiki\Logger\LoggerFactory;
  27
  28 /**
  29  * Legacy MediaWiki-specific class for generating database load balancers
  30  * @ingroup Database
  31  */
  32 abstract class LBFactoryMW extends LBFactory implements DestructibleService {
  33         /** @noinspection PhpMissingParentConstructorInspection */
  34         /**
  35          * Construct a factory based on a configuration array (typically from $wgLBFactoryConf)
  36          * @param array $conf
  37          * @TODO: inject objects via dependency framework
  38          */
  39         public function __construct( array $conf ) {
  40                 global $wgCommandLineMode, $wgSQLMode, $wgDBmysql5;
  41
  42                 $defaults = [
  43                         'localDomain' => wfWikiID(),
  44                         'hostname' => wfHostname(),
  45                         'trxProfiler' => Profiler::instance()->getTransactionProfiler(),
  46                         'replLogger' => LoggerFactory::getInstance( 'DBReplication' ),
  47                         'queryLogger' => LoggerFactory::getInstance( 'wfLogDBError' ),
  48                         'connLogger' => LoggerFactory::getInstance( 'wfLogDBError' ),
  49                         'perfLogger' => LoggerFactory::getInstance( 'DBPerformance' ),
  50                         'errorLogger' => [ MWExceptionHandler::class, 'logException' ]
  51                 ];
  52                 // Use APC/memcached style caching, but avoids loops with CACHE_DB (T141804)
  53                 $sCache = ObjectCache::getLocalServerInstance();
  54                 if ( $sCache->getQoS( $sCache::ATTR_EMULATION ) > $sCache::QOS_EMULATION_SQL ) {
  55                         $defaults['srvCache'] = $sCache;
  56                 }
  57                 $cCache = ObjectCache::getLocalClusterInstance();
  58                 if ( $cCache->getQoS( $cCache::ATTR_EMULATION ) > $cCache::QOS_EMULATION_SQL ) {
  59                         $defaults['memCache'] = $cCache;
  60                 }
  61                 $wCache = ObjectCache::getMainWANInstance();
  62                 if ( $wCache->getQoS( $wCache::ATTR_EMULATION ) > $wCache::QOS_EMULATION_SQL ) {
  63                         $defaults['wanCache'] = $wCache;
  64                 }
  65
  66                 $this->agent = isset( $params['agent'] ) ? $params['agent'] : '';
  67                 $this->cliMode = isset( $params['cliMode'] ) ? $params['cliMode'] : $wgCommandLineMode;
  68
  69                 if ( isset( $conf['serverTemplate'] ) ) { // LBFactoryMulti
  70                         $conf['serverTemplate']['sqlMode'] = $wgSQLMode;
  71                         $conf['serverTemplate']['utf8Mode'] = $wgDBmysql5;
  72                 }
  73
  74                 parent::__construct( $conf + $defaults );
  75         }
  76
  77         /**
  78          * Returns the LBFactory class to use and the load balancer configuration.
  79          *
  80          * @todo instead of this, use a ServiceContainer for managing the different implementations.
  81          *
  82          * @param array $config (e.g. $wgLBFactoryConf)
  83          * @return string Class name
  84          */
  85         public static function getLBFactoryClass( array $config ) {
  86                 // For configuration backward compatibility after removing
  87                 // underscores from class names in MediaWiki 1.23.
  88                 $bcClasses = [
  89                         'LBFactory_Simple' => 'LBFactorySimple',
  90                         'LBFactory_Single' => 'LBFactorySingle',
  91                         'LBFactory_Multi' => 'LBFactoryMulti'
  92                 ];
  93
  94                 $class = $config['class'];
  95
  96                 if ( isset( $bcClasses[$class] ) ) {
  97                         $class = $bcClasses[$class];
  98                         wfDeprecated(
  99                                 '$wgLBFactoryConf must be updated. See RELEASE-NOTES for details',
 100                                 '1.23'
 101                         );
 102                 }
 103
 104                 return $class;
 105         }
 106
 107         /**
 108          * @return bool
 109          * @since 1.27
 110          * @deprecated Since 1.28; use laggedReplicaUsed()
 111          */
 112         public function laggedSlaveUsed() {
 113                 return $this->laggedReplicaUsed();
 114         }
 115
 116         protected function newChronologyProtector() {
 117                 $request = RequestContext::getMain()->getRequest();
 118                 $chronProt = new ChronologyProtector(
 119                         ObjectCache::getMainStashInstance(),
 120                         [
 121                                 'ip' => $request->getIP(),
 122                                 'agent' => $request->getHeader( 'User-Agent' ),
 123                         ],
 124                         $request->getFloat( 'cpPosTime', $request->getCookie( 'cpPosTime', '' ) )
 125                 );
 126                 if ( PHP_SAPI === 'cli' ) {
 127                         $chronProt->setEnabled( false );
 128                 } elseif ( $request->getHeader( 'ChronologyProtection' ) === 'false' ) {
 129                         // Request opted out of using position wait logic. This is useful for requests
 130                         // done by the job queue or background ETL that do not have a meaningful session.
 131                         $chronProt->setWaitEnabled( false );
 132                 }
 133
 134                 return $chronProt;
 135         }
 136
 137         /**
 138          * Append ?cpPosTime parameter to a URL for ChronologyProtector purposes if needed
 139          *
 140          * Note that unlike cookies, this works accross domains
 141          *
 142          * @param string $url
 143          * @param float $time UNIX timestamp just before shutdown() was called
 144          * @return string
 145          * @since 1.28
 146          */
 147         public function appendPreShutdownTimeAsQuery( $url, $time ) {
 148                 $usedCluster = 0;
 149                 $this->forEachLB( function ( LoadBalancer $lb ) use ( &$usedCluster ) {
 150                         $usedCluster |= ( $lb->getServerCount() > 1 );
 151                 } );
 152
 153                 if ( !$usedCluster ) {
 154                         return $url; // no master/replica clusters touched
 155                 }
 156
 157                 return wfAppendQuery( $url, [ 'cpPosTime' => $time ] );
 158         }
 159 }