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 LBFactory;
  10 use Liuggio\StatsdClient\Factory\StatsdDataFactory;
  11 use LoadBalancer;
  12 use MediaWiki\Services\ServiceContainer;
  13 use SearchEngine;
  14 use SearchEngineConfig;
  15 use SearchEngineFactory;
  16 use SiteLookup;
  17 use SiteStore;
  18 use SkinFactory;
  19
  20 /**
  21  * Service locator for MediaWiki core services.
  22  *
  23  * This program is free software; you can redistribute it and/or modify
  24  * it under the terms of the GNU General Public License as published by
  25  * the Free Software Foundation; either version 2 of the License, or
  26  * (at your option) any later version.
  27  *
  28  * This program is distributed in the hope that it will be useful,
  29  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  30  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  31  * GNU General Public License for more details.
  32  *
  33  * You should have received a copy of the GNU General Public License along
  34  * with this program; if not, write to the Free Software Foundation, Inc.,
  35  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  36  * http://www.gnu.org/copyleft/gpl.html
  37  *
  38  * @file
  39  *
  40  * @since 1.27
  41  */
  42
  43 /**
  44  * MediaWikiServices is the service locator for the application scope of MediaWiki.
  45  * Its implemented as a simple configurable DI container.
  46  * MediaWikiServices acts as a top level factory/registry for top level services, and builds
  47  * the network of service objects that defines MediaWiki's application logic.
  48  * It acts as an entry point to MediaWiki's dependency injection mechanism.
  49  *
  50  * Services are defined in the "wiring" array passed to the constructor,
  51  * or by calling defineService().
  52  *
  53  * @see docs/injection.txt for an overview of using dependency injection in the
  54  *      MediaWiki code base.
  55  */
  56 class MediaWikiServices extends ServiceContainer {
  57
  58         /**
  59          * Returns the global default instance of the top level service locator.
  60          *
  61          * The default instance is initialized using the service instantiator functions
  62          * defined in ServiceWiring.php.
  63          *
  64          * @note This should only be called by static functions! The instance returned here
  65          * should not be passed around! Objects that need access to a service should have
  66          * that service injected into the constructor, never a service locator!
  67          *
  68          * @return MediaWikiServices
  69          */
  70         public static function getInstance() {
  71                 static $instance = null;
  72
  73                 if ( $instance === null ) {
  74                         // NOTE: constructing GlobalVarConfig here is not particularly pretty,
  75                         // but some information from the global scope has to be injected here,
  76                         // even if it's just a file name or database credentials to load
  77                         // configuration from.
  78                         $config = new GlobalVarConfig();
  79                         $instance = new self( $config );
  80
  81                         // Load the default wiring from the specified files.
  82                         $wiringFiles = $config->get( 'ServiceWiringFiles' );
  83                         $instance->loadWiringFiles( $wiringFiles );
  84
  85                         // Provide a traditional hook point to allow extensions to configure services.
  86                         Hooks::run( 'MediaWikiServices', [ $instance ] );
  87                 }
  88
  89                 return $instance;
  90         }
  91
  92         /**
  93          * @param Config $config The Config object to be registered as the 'BootstrapConfig' service.
  94          *        This has to contain at least the information needed to set up the 'ConfigFactory'
  95          *        service.
  96          */
  97         public function __construct( Config $config ) {
  98                 parent::__construct();
  99
 100                 // register the given Config object as the bootstrap config service.
 101                 $this->defineService( 'BootstrapConfig', function() use ( $config ) {
 102                         return $config;
 103                 } );
 104         }
 105
 106         /**
 107          * Returns the Config object containing the bootstrap configuration.
 108          * Bootstrap configuration would typically include database credentials
 109          * and other information that may be needed before the ConfigFactory
 110          * service can be instantiated.
 111          *
 112          * @note This should only be used during bootstrapping, in particular
 113          * when creating the MainConfig service. Application logic should
 114          * use getMainConfig() to get a Config instances.
 115          *
 116          * @return Config
 117          */
 118         public function getBootstrapConfig() {
 119                 return $this->getService( 'BootstrapConfig' );
 120         }
 121
 122         /**
 123          * @return ConfigFactory
 124          */
 125         public function getConfigFactory() {
 126                 return $this->getService( 'ConfigFactory' );
 127         }
 128
 129         /**
 130          * Returns the Config object that provides configuration for MediaWiki core.
 131          * This may or may not be the same object that is returned by getBootstrapConfig().
 132          *
 133          * @return Config
 134          */
 135         public function getMainConfig() {
 136                 return $this->getService( 'MainConfig' );
 137         }
 138
 139         /**
 140          * @return SiteLookup
 141          */
 142         public function getSiteLookup() {
 143                 return $this->getService( 'SiteLookup' );
 144         }
 145
 146         /**
 147          * @return SiteStore
 148          */
 149         public function getSiteStore() {
 150                 return $this->getService( 'SiteStore' );
 151         }
 152
 153         /**
 154          * @return StatsdDataFactory
 155          */
 156         public function getStatsdDataFactory() {
 157                 return $this->getService( 'StatsdDataFactory' );
 158         }
 159
 160         /**
 161          * @return EventRelayerGroup
 162          */
 163         public function getEventRelayerGroup() {
 164                 return $this->getService( 'EventRelayerGroup' );
 165         }
 166
 167         /**
 168          * @return SearchEngine
 169          */
 170         public function newSearchEngine() {
 171                 // New engine object every time, since they keep state
 172                 return $this->getService( 'SearchEngineFactory' )->create();
 173         }
 174
 175         /**
 176          * @return SearchEngineFactory
 177          */
 178         public function getSearchEngineFactory() {
 179                 return $this->getService( 'SearchEngineFactory' );
 180         }
 181
 182         /**
 183          * @return SearchEngineConfig
 184          */
 185         public function getSearchEngineConfig() {
 186                 return $this->getService( 'SearchEngineConfig' );
 187         }
 188
 189         /**
 190          * @return SkinFactory
 191          */
 192         public function getSkinFactory() {
 193                 return $this->getService( 'SkinFactory' );
 194         }
 195
 196         ///////////////////////////////////////////////////////////////////////////
 197         // NOTE: When adding a service getter here, don't forget to add a test
 198         // case for it in MediaWikiServicesTest::provideGetters() and in
 199         // MediaWikiServicesTest::provideGetService()!
 200         ///////////////////////////////////////////////////////////////////////////
 201
 202 }