includes/MediaWikiServices.php

   1 <?php
   2 namespace MediaWiki;
   3
   4 use ConfigFactory;
   5 use EventRelayerGroup;
   6 use GlobalVarConfig;
   7 use Config;
   8 use Hooks;
   9 use Liuggio\StatsdClient\Factory\StatsdDataFactory;
  10 use MediaWiki\Services\ServiceContainer;
  11 use SearchEngine;
  12 use SearchEngineConfig;
  13 use SearchEngineFactory;
  14 use SiteLookup;
  15 use SiteStore;
  16 use SkinFactory;
  17
  18 /**
  19  * Service locator for MediaWiki core services.
  20  *
  21  * This program is free software; you can redistribute it and/or modify
  22  * it under the terms of the GNU General Public License as published by
  23  * the Free Software Foundation; either version 2 of the License, or
  24  * (at your option) any later version.
  25  *
  26  * This program is distributed in the hope that it will be useful,
  27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  29  * GNU General Public License for more details.
  30  *
  31  * You should have received a copy of the GNU General Public License along
  32  * with this program; if not, write to the Free Software Foundation, Inc.,
  33  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  34  * http://www.gnu.org/copyleft/gpl.html
  35  *
  36  * @file
  37  *
  38  * @since 1.27
  39  */
  40
  41 /**
  42  * MediaWikiServices is the service locator for the application scope of MediaWiki.
  43  * Its implemented as a simple configurable DI container.
  44  * MediaWikiServices acts as a top level factory/registry for top level services, and builds
  45  * the network of service objects that defines MediaWiki's application logic.
  46  * It acts as an entry point to MediaWiki's dependency injection mechanism.
  47  *
  48  * Services are defined in the "wiring" array passed to the constructor,
  49  * or by calling defineService().
  50  *
  51  * @see docs/injection.txt for an overview of using dependency injection in the
  52  *      MediaWiki code base.
  53  */
  54 class MediaWikiServices extends ServiceContainer {
  55
  56         /**
  57          * Returns the global default instance of the top level service locator.
  58          *
  59          * The default instance is initialized using the service instantiator functions
  60          * defined in ServiceWiring.php.
  61          *
  62          * @note This should only be called by static functions! The instance returned here
  63          * should not be passed around! Objects that need access to a service should have
  64          * that service injected into the constructor, never a service locator!
  65          *
  66          * @return MediaWikiServices
  67          */
  68         public static function getInstance() {
  69                 static $instance = null;
  70
  71                 if ( $instance === null ) {
  72                         // NOTE: constructing GlobalVarConfig here is not particularly pretty,
  73                         // but some information from the global scope has to be injected here,
  74                         // even if it's just a file name or database credentials to load
  75                         // configuration from.
  76                         $config = new GlobalVarConfig();
  77                         $instance = new self( $config );
  78
  79                         // Load the default wiring from the specified files.
  80                         $wiringFiles = $config->get( 'ServiceWiringFiles' );
  81                         $instance->loadWiringFiles( $wiringFiles );
  82
  83                         // Provide a traditional hook point to allow extensions to configure services.
  84                         Hooks::run( 'MediaWikiServices', [ $instance ] );
  85                 }
  86
  87                 return $instance;
  88         }
  89
  90         /**
  91          * @param Config $config The Config object to be registered as the 'BootstrapConfig' service.
  92          *        This has to contain at least the information needed to set up the 'ConfigFactory'
  93          *        service.
  94          */
  95         public function __construct( Config $config ) {
  96                 parent::__construct();
  97
  98                 // register the given Config object as the bootstrap config service.
  99                 $this->defineService( 'BootstrapConfig', function() use ( $config ) {
 100                         return $config;
 101                 } );
 102         }
 103
 104         /**
 105          * Returns the Config object containing the bootstrap configuration.
 106          * Bootstrap configuration would typically include database credentials
 107          * and other information that may be needed before the ConfigFactory
 108          * service can be instantiated.
 109          *
 110          * @note This should only be used during bootstrapping, in particular
 111          * when creating the MainConfig service. Application logic should
 112          * use getMainConfig() to get a Config instances.
 113          *
 114          * @return Config
 115          */
 116         public function getBootstrapConfig() {
 117                 return $this->getService( 'BootstrapConfig' );
 118         }
 119
 120         /**
 121          * @return ConfigFactory
 122          */
 123         public function getConfigFactory() {
 124                 return $this->getService( 'ConfigFactory' );
 125         }
 126
 127         /**
 128          * Returns the Config object that provides configuration for MediaWiki core.
 129          * This may or may not be the same object that is returned by getBootstrapConfig().
 130          *
 131          * @return Config
 132          */
 133         public function getMainConfig() {
 134                 return $this->getService( 'MainConfig' );
 135         }
 136
 137         /**
 138          * @return SiteLookup
 139          */
 140         public function getSiteLookup() {
 141                 return $this->getService( 'SiteLookup' );
 142         }
 143
 144         /**
 145          * @return SiteStore
 146          */
 147         public function getSiteStore() {
 148                 return $this->getService( 'SiteStore' );
 149         }
 150
 151         /**
 152          * @return StatsdDataFactory
 153          */
 154         public function getStatsdDataFactory() {
 155                 return $this->getService( 'StatsdDataFactory' );
 156         }
 157
 158         /**
 159          * @return EventRelayerGroup
 160          */
 161         public function getEventRelayerGroup() {
 162                 return $this->getService( 'EventRelayerGroup' );
 163         }
 164
 165         /**
 166          * @return SearchEngine
 167          */
 168         public function newSearchEngine() {
 169                 // New engine object every time, since they keep state
 170                 return $this->getService( 'SearchEngineFactory' )->create();
 171         }
 172
 173         /**
 174          * @return SearchEngineFactory
 175          */
 176         public function getSearchEngineFactory() {
 177                 return $this->getService( 'SearchEngineFactory' );
 178         }
 179
 180         /**
 181          * @return SearchEngineConfig
 182          */
 183         public function getSearchEngineConfig() {
 184                 return $this->getService( 'SearchEngineConfig' );
 185         }
 186
 187         /**
 188          * @return SkinFactory
 189          */
 190         public function getSkinFactory() {
 191                 return $this->getService( 'SkinFactory' );
 192         }
 193
 194         ///////////////////////////////////////////////////////////////////////////
 195         // NOTE: When adding a service getter here, don't forget to add a test
 196         // case for it in MediaWikiServicesTest::provideGetters() and in
 197         // MediaWikiServicesTest::provideGetService()!
 198         ///////////////////////////////////////////////////////////////////////////
 199
 200 }