<?php
namespace MediaWiki;
-use ApiQueryInfo;
-use CentralIdLookup;
-use Config;
use ConfigFactory;
-use DeferredUpdates;
-use FileBackendGroup;
use GlobalVarConfig;
+use Config;
use Hooks;
-use IP;
-use JobQueueAggregator;
-use Language;
use LBFactory;
-use LinkCache;
use LoadBalancer;
-use LockManagerGroup;
-use MagicWord;
-use MediaHandler;
use MediaWiki\Services\ServiceContainer;
-use MediaWiki\Session\SessionManager;
-use MessageCache;
-use MWException;
-use MWNamespace;
-use MWTidy;
-use ObjectCache;
-use RedisConnectionPool;
-use RepoGroup;
-use RequestContext;
-use ResourceLoader;
use SiteLookup;
use SiteStore;
-use SpecialPageFactory;
-use Title;
-use User;
/**
* Service locator for MediaWiki core services.
*/
class MediaWikiServices extends ServiceContainer {
- /**
- * @var MediaWikiServices|null
- */
- private static $instance = null;
-
/**
* Returns the global default instance of the top level service locator.
*
* @return MediaWikiServices
*/
public static function getInstance() {
- if ( self::$instance === null ) {
+ static $instance = null;
+
+ if ( $instance === null ) {
// NOTE: constructing GlobalVarConfig here is not particularly pretty,
// but some information from the global scope has to be injected here,
// even if it's just a file name or database credentials to load
// configuration from.
- $bootstrapConfig = new GlobalVarConfig();
- self::$instance = self::newInstance( $bootstrapConfig );
- }
+ $config = new GlobalVarConfig();
+ $instance = new self( $config );
- return self::$instance;
- }
+ // Load the default wiring from the specified files.
+ $wiringFiles = $config->get( 'ServiceWiringFiles' );
+ $instance->loadWiringFiles( $wiringFiles );
- /**
- * Replaces the global MediaWikiServices instance.
- *
- * @note This is for use in PHPUnit tests only!
- *
- * @throws MWException if called outside of PHPUnit tests.
- *
- * @param MediaWikiServices $services The new MediaWikiServices object.
- *
- * @return MediaWikiServices The old MediaWikiServices object, so it can be restored later.
- */
- public static function forceGlobalInstance( MediaWikiServices $services ) {
- if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
- throw new MWException( __METHOD__ . ' must not be used outside unit tests.' );
- }
-
- $old = self::getInstance();
- self::$instance = $services;
-
- self::resetLegacyServices();
-
- return $old;
- }
-
- /**
- * Creates a new instance of MediaWikiServices and sets it as the global default
- * instance. getInstance() will return a different MediaWikiServices object
- * after every call to resetGlobalServiceLocator().
- *
- * @warning This should not be used during normal operation. It is intended for use
- * when the configuration has changed significantly since bootstrap time, e.g.
- * during the installation process or during testing.
- *
- * @warning Calling resetGlobalServiceLocator() may leave the application in an inconsistent
- * state. Calling this is only safe under the ASSUMPTION that NO REFERENCE to
- * any of the services managed by MediaWikiServices exist. If any service objects
- * managed by the old MediaWikiServices instance remain in use, they may INTERFERE
- * with the operation of the services managed by the new MediaWikiServices.
- * Operating with a mix of services created by the old and the new
- * MediaWikiServices instance may lead to INCONSISTENCIES and even DATA LOSS!
- * Any class implementing LAZY LOADING is especially prone to this problem,
- * since instances would typically retain a reference to a storage layer service.
- *
- * @see forceGlobalInstance()
- * @see resetGlobalInstance()
- * @see resetBetweenTest()
- *
- * @param Config|null $bootstrapConfig The Config object to be registered as the
- * 'BootstrapConfig' service. This has to contain at least the information
- * needed to set up the 'ConfigFactory' service. If not given, the bootstrap
- * config of the old instance of MediaWikiServices will be re-used. If there
- * was no previous instance, a new GlobalVarConfig object will be used to
- * bootstrap the services.
- *
- * @throws MWException
- */
- public static function resetGlobalInstance( Config $bootstrapConfig = null ) {
- if ( self::$instance === null ) {
- // no global instance yet, nothing to reset
- return;
+ // Provide a traditional hook point to allow extensions to configure services.
+ Hooks::run( 'MediaWikiServices', [ $instance ] );
}
- if ( $bootstrapConfig === null ) {
- $bootstrapConfig = self::$instance->getBootstrapConfig();
- }
-
- self::$instance->destroy();
-
- self::$instance = self::newInstance( $bootstrapConfig );
-
- self::resetLegacyServices();
- }
-
- /**
- * Creates a new MediaWikiServices instance and initializes it according to the
- * given $bootstrapConfig. In particular, all wiring files defined in the
- * ServiceWiringFiles setting are loaded, and the MediaWikiServices hook is called.
- *
- * @param Config|null $bootstrapConfig The Config object to be registered as the
- * 'BootstrapConfig' service. This has to contain at least the information
- * needed to set up the 'ConfigFactory' service. If not provided, any call
- * to getBootstrapConfig(), getConfigFactory, or getMainConfig will fail.
- * A MediaWikiServices instance without access to configuration is called
- * "primordial".
- *
- * @return MediaWikiServices
- * @throws MWException
- */
- private static function newInstance( Config $bootstrapConfig ) {
- $instance = new self( $bootstrapConfig );
-
- // Load the default wiring from the specified files.
- $wiringFiles = $bootstrapConfig->get( 'ServiceWiringFiles' );
- $instance->loadWiringFiles( $wiringFiles );
-
- // Provide a traditional hook point to allow extensions to configure services.
- Hooks::run( 'MediaWikiServices', [ $instance ] );
-
return $instance;
}
- /**
- * Resets global instances of services that have not yet been ported to using
- * MediaWikiServices to manage their default instance.
- *
- * @note eventually, all global service instances are to be managed by MediaWikiServices.
- * To emulate the effect of resetting the global service locator, we reset the individual
- * static singletons for now.
- *
- * @note As long as we don't know the interdependencies between the services, the only way
- * to reset services consistently is to reset all services at once. This should be ok since
- * there should rarely be a need to reset all processes.
- */
- private static function resetLegacyServices() {
- global $wgContLang, $wgUser, $wgMemc, $wgRequest;
-
- $services = self::getInstance();
- $config = $services->getMainConfig();
-
- // NOTE: all the services instance that get reset below should be migrated
- // to be managed by MediaWikiServices. Eventually, this method can then be
- // removed.
-
- User::resetIdByNameCache();
- LinkCache::singleton()->clear();
- Title::clearCaches();
-
- MWTidy::destroySingleton();
- MagicWord::clearCache();
- SpecialPageFactory::resetList();
- JobQueueAggregator::destroySingleton();
- DeferredUpdates::clearPendingUpdates();
- CentralIdLookup::resetCache();
- MediaHandler::resetCache();
- IP::clearCaches();
- ResourceLoader::clearCache();
-
- ApiQueryInfo::resetTokenCache();
-
- RepoGroup::destroySingleton();
-
- MessageCache::destroyInstance();
-
- MWNamespace::getCanonicalNamespaces( true ); # reset namespace cache
- Language::$mLangObjCache = [];
- Language::getLocalisationCache()->unloadAll();
-
- ObjectCache::clear();
- RedisConnectionPool::destroySingletons();
- FileBackendGroup::destroySingleton();
- LockManagerGroup::destroySingletons();
-
- RequestContext::resetMain();
- $wgRequest = RequestContext::getMain()->getRequest(); // BackCompat
-
- $wgContLang = Language::factory( $config->get( 'LanguageCode' ) );
- $wgContLang->resetNamespaces(); # reset namespace cache
-
- $wgMemc = ObjectCache::getLocalClusterInstance();
- $wgUser = RequestContext::getMain()->getUser();
-
- SessionManager::resetCache();
-
- // Provide a hook point for extensions that need to reset global service instances.
- Hooks::run( 'MediaWikiServices::resetLegacyServices', [ $services ] );
- }
-
- /**
- * Disables all storage layer services. After calling this, any attempt to access the
- * storage layer will result in an error. Use resetGlobalInstance() to restore normal
- * operation.
- *
- * @warning This is intended for extreme situations only and should never be used
- * while serving normal web requests. Legitimate use cases for this method include
- * the installation process. Test fixtures may also use this, if the fixture relies
- * on globalState.
- *
- * @see resetGlobalInstance()
- * @see resetChildProcessServices()
- */
- public static function disableStorageBackend() {
- // TODO: also disable some Caches, JobQueues, etc
- $destroy = [ 'DBLoadBalancer', 'DBLoadBalancerFactory' ];
- $services = self::getInstance();
-
- foreach ( $destroy as $name ) {
- $services->disableService( $name );
- }
- }
-
- /**
- * Resets any services that may have become stale after a child process
- * returns from after pcntl_fork(). It's also safe, but generally unnecessary,
- * to call this method from the parent process.
- *
- * @note This is intended for use in the context of process forking only!
- *
- * @see resetGlobalInstance()
- * @see disableStorageBackend()
- */
- public static function resetChildProcessServices() {
- // NOTE: for now, just reset everything. Since we don't know the interdependencies
- // between services, we can't do this more selectively at this time.
- self::resetGlobalInstance();
-
- // Child, reseed because there is no bug in PHP:
- // http://bugs.php.net/bug.php?id=42465
- mt_srand( getmypid() );
- }
-
- /**
- * Resets the given service for testing purposes.
- *
- * @warning This is generally unsafe! Other services may still retain references
- * to the stale service instance, leading to failures and inconsistencies. Subclasses
- * may use this method to reset specific services under specific instances, but
- * it should not be exposed to application logic.
- *
- * @note With proper dependency injection used throughout the codebase, this method
- * should not be needed. It is provided to allow tests that pollute global service
- * instances to clean up.
- *
- * @param string $name
- * @param string $destroy Whether the service instance should be destroyed if it exists.
- * When set to false, any existing service instance will effectively be detached
- * from the container.
- *
- * @throws MWException if called outside of PHPUnit tests.
- */
- public function resetServiceForTesting( $name, $destroy = true ) {
- if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
- throw new MWException( 'resetServiceForTesting() must not be used outside unit tests.' );
- }
-
- $this->resetService( $name, $destroy );
- }
-
- /**
- * Convenience method that throws an exception if called outside the service bootstrapping
- * phase as indicated by the MW_SERVICE_BOOTSTRAP_COMPLETE constant - that is, after
- * Setup.php has called resetGlobalInstance(). Additionally, no exception is thrown if
- * this method is called during unit testing (as indicated by MW_PHPUNIT_TEST) or
- * during installation (as indicated by MEDIAWIKI_INSTALL).
- *
- * This method is intended to be used to safeguard against accidentally resetting
- * global service instances that are not yet managed by MediaWikiServices. It is
- * defined here in the MediaWikiServices services class to keep the knowledge about
- * how the bootstrapping phase is managed central.
- *
- * @param string $method the name of the caller method, as given by __METHOD__.
- *
- * @throws MWException if called outside bootstrap mode.
- *
- * @see resetGlobalInstance()
- * @see forceGlobalInstance()
- * @see disableStorageBackend()
- */
- public static function failUnlessBootstrapping( $method ) {
- if ( !defined( 'MW_PHPUNIT_TEST' )
- && !defined( 'MEDIAWIKI_INSTALL' )
- && defined( 'MW_SERVICE_BOOTSTRAP_COMPLETE' )
- ) {
- throw new MWException( $method . ' may only be called during bootstrapping unit tests!' );
- }
-
- ObjectCache::clear();
- }
-
/**
* @param Config $config The Config object to be registered as the 'BootstrapConfig' service.
* This has to contain at least the information needed to set up the 'ConfigFactory'
public function __construct( Config $config ) {
parent::__construct();
- // Register the given Config object as the bootstrap config service.
+ // register the given Config object as the bootstrap config service.
$this->defineService( 'BootstrapConfig', function() use ( $config ) {
return $config;
} );
}
- // CONVENIENCE GETTERS ////////////////////////////////////////////////////
-
/**
* Returns the Config object containing the bootstrap configuration.
* Bootstrap configuration would typically include database credentials
return $this->getService( 'SiteStore' );
}
- /**
- * @return LBFactory
- */
- public function getDBLoadBalancerFactory() {
- return $this->getService( 'DBLoadBalancerFactory' );
- }
-
- /**
- * @return LoadBalancer The main DB load balancer for the local wiki.
- */
- public function getDBLoadBalancer() {
- return $this->getService( 'DBLoadBalancer' );
- }
-
///////////////////////////////////////////////////////////////////////////
// NOTE: When adding a service getter here, don't forget to add a test
// case for it in MediaWikiServicesTest::provideGetters() and in