includes/filebackend/lockmanager/LockManagerGroup.php

   1 <?php
   2 /**
   3  * Lock manager registration handling.
   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 LockManager
  22  */
  23 use MediaWiki\MediaWikiServices;
  24 use MediaWiki\Logger\LoggerFactory;
  25
  26 /**
  27  * Class to handle file lock manager registration
  28  *
  29  * @ingroup LockManager
  30  * @since 1.19
  31  */
  32 class LockManagerGroup {
  33         /** @var LockManagerGroup[] (domain => LockManagerGroup) */
  34         protected static $instances = [];
  35
  36         protected $domain; // string; domain (usually wiki ID)
  37
  38         /** @var array Array of (name => ('class' => ..., 'config' => ..., 'instance' => ...)) */
  39         protected $managers = [];
  40
  41         /**
  42          * @param string $domain Domain (usually wiki ID)
  43          */
  44         protected function __construct( $domain ) {
  45                 $this->domain = $domain;
  46         }
  47
  48         /**
  49          * @param bool|string $domain Domain (usually wiki ID). Default: false.
  50          * @return LockManagerGroup
  51          */
  52         public static function singleton( $domain = false ) {
  53                 if ( $domain === false ) {
  54                         $domain = WikiMap::getCurrentWikiDomain()->getId();
  55                 }
  56
  57                 if ( !isset( self::$instances[$domain] ) ) {
  58                         self::$instances[$domain] = new self( $domain );
  59                         self::$instances[$domain]->initFromGlobals();
  60                 }
  61
  62                 return self::$instances[$domain];
  63         }
  64
  65         /**
  66          * Destroy the singleton instances
  67          */
  68         public static function destroySingletons() {
  69                 self::$instances = [];
  70         }
  71
  72         /**
  73          * Register lock managers from the global variables
  74          */
  75         protected function initFromGlobals() {
  76                 global $wgLockManagers;
  77
  78                 $this->register( $wgLockManagers );
  79         }
  80
  81         /**
  82          * Register an array of file lock manager configurations
  83          *
  84          * @param array $configs
  85          * @throws Exception
  86          */
  87         protected function register( array $configs ) {
  88                 foreach ( $configs as $config ) {
  89                         $config['domain'] = $this->domain;
  90                         if ( !isset( $config['name'] ) ) {
  91                                 throw new Exception( "Cannot register a lock manager with no name." );
  92                         }
  93                         $name = $config['name'];
  94                         if ( !isset( $config['class'] ) ) {
  95                                 throw new Exception( "Cannot register lock manager `{$name}` with no class." );
  96                         }
  97                         $class = $config['class'];
  98                         unset( $config['class'] ); // lock manager won't need this
  99                         $this->managers[$name] = [
 100                                 'class' => $class,
 101                                 'config' => $config,
 102                                 'instance' => null
 103                         ];
 104                 }
 105         }
 106
 107         /**
 108          * Get the lock manager object with a given name
 109          *
 110          * @param string $name
 111          * @return LockManager
 112          * @throws Exception
 113          */
 114         public function get( $name ) {
 115                 if ( !isset( $this->managers[$name] ) ) {
 116                         throw new Exception( "No lock manager defined with the name `$name`." );
 117                 }
 118                 // Lazy-load the actual lock manager instance
 119                 if ( !isset( $this->managers[$name]['instance'] ) ) {
 120                         $class = $this->managers[$name]['class'];
 121                         $config = $this->managers[$name]['config'];
 122                         if ( $class === DBLockManager::class ) {
 123                                 $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
 124                                 $lb = $lbFactory->newMainLB( $config['domain'] );
 125                                 $dbw = $lb->getLazyConnectionRef( DB_MASTER, [], $config['domain'] );
 126
 127                                 $config['dbServers']['localDBMaster'] = $dbw;
 128                                 $config['srvCache'] = ObjectCache::getLocalServerInstance( 'hash' );
 129                         }
 130                         $config['logger'] = LoggerFactory::getInstance( 'LockManager' );
 131
 132                         $this->managers[$name]['instance'] = new $class( $config );
 133                 }
 134
 135                 return $this->managers[$name]['instance'];
 136         }
 137
 138         /**
 139          * Get the config array for a lock manager object with a given name
 140          *
 141          * @param string $name
 142          * @return array
 143          * @throws Exception
 144          */
 145         public function config( $name ) {
 146                 if ( !isset( $this->managers[$name] ) ) {
 147                         throw new Exception( "No lock manager defined with the name `$name`." );
 148                 }
 149                 $class = $this->managers[$name]['class'];
 150
 151                 return [ 'class' => $class ] + $this->managers[$name]['config'];
 152         }
 153
 154         /**
 155          * Get the default lock manager configured for the site.
 156          * Returns NullLockManager if no lock manager could be found.
 157          *
 158          * @return LockManager
 159          */
 160         public function getDefault() {
 161                 return isset( $this->managers['default'] )
 162                         ? $this->get( 'default' )
 163                         : new NullLockManager( [] );
 164         }
 165
 166         /**
 167          * Get the default lock manager configured for the site
 168          * or at least some other effective configured lock manager.
 169          * Throws an exception if no lock manager could be found.
 170          *
 171          * @return LockManager
 172          * @throws Exception
 173          */
 174         public function getAny() {
 175                 return isset( $this->managers['default'] )
 176                         ? $this->get( 'default' )
 177                         : $this->get( 'fsLockManager' );
 178         }
 179 }