+ /**
+ * 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();
+ }
+