MediaWikiServices::newSearchEngine() - Code Metrics - Inspection of "Daily Inspection: Merge "Make LBFactoryTest.php pa..." - wikimedia/mediawiki - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Branch — master (9ca75b)

unknown

created 2016-10-29 17:16 UTC

MediaWikiServices::newSearchEngine() A

↳ Parent: MediaWikiServices

Complexity

Conditions	1
Paths	1

Size

Total Lines	4
Code Lines	2

Duplication

Lines	0
Ratio	0 %

Importance

Changes

Metric	Value
cc	1
eloc	2
nc	1
nop	0
dl	0
loc	4
rs	10
c	0
b	0
f	0

<?php
namespace MediaWiki;

use Config;
use ConfigFactory;
use CryptHKDF;
use CryptRand;
use EventRelayerGroup;
use GenderCache;
use GlobalVarConfig;
use Hooks;
use LBFactory;
use LinkCache;
use Liuggio\StatsdClient\Factory\StatsdDataFactory;
use LoadBalancer;
use MediaHandlerFactory;
use MediaWiki\Linker\LinkRenderer;
use MediaWiki\Linker\LinkRendererFactory;
use MediaWiki\Services\SalvageableService;
use MediaWiki\Services\ServiceContainer;
use MediaWiki\Services\NoSuchServiceException;
use MWException;
use MimeAnalyzer;
use ObjectCache;
use Parser;
use ProxyLookup;
use SearchEngine;
use SearchEngineConfig;
use SearchEngineFactory;
use SiteLookup;
use SiteStore;
use WatchedItemStore;
use WatchedItemQueryService;
use SkinFactory;
use TitleFormatter;
use TitleParser;
use VirtualRESTServiceClient;
use MediaWiki\Interwiki\InterwikiLookup;

/**
 * Service locator for MediaWiki core services.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 *
 * @since 1.27
 */

/**
 * MediaWikiServices is the service locator for the application scope of MediaWiki.
 * Its implemented as a simple configurable DI container.
 * MediaWikiServices acts as a top level factory/registry for top level services, and builds
 * the network of service objects that defines MediaWiki's application logic.
 * It acts as an entry point to MediaWiki's dependency injection mechanism.
 *
 * Services are defined in the "wiring" array passed to the constructor,
 * or by calling defineService().
 *
 * @see docs/injection.txt for an overview of using dependency injection in the
 *      MediaWiki code base.
 */
class MediaWikiServices extends ServiceContainer {

	/**
	 * @var MediaWikiServices|null
	 */
	private static $instance = null;

	/**
	 * Returns the global default instance of the top level service locator.
	 *
	 * @since 1.27
	 *
	 * The default instance is initialized using the service instantiator functions
	 * defined in ServiceWiring.php.
	 *
	 * @note This should only be called by static functions! The instance returned here
	 * should not be passed around! Objects that need access to a service should have
	 * that service injected into the constructor, never a service locator!
	 *
	 * @return MediaWikiServices
	 */
	public static function getInstance() {
		if ( self::$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, 'load' );
		}

		return self::$instance;
	}

	/**
	 * Replaces the global MediaWikiServices instance.
	 *
	 * @since 1.28
	 *
	 * @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;

		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 resetGlobalInstance().
	 *
	 * @since 1.28
	 *
	 * @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 resetGlobalInstance() 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.
	 *
	 * @param string $quick Set this to "quick" to allow expensive resources to be re-used.
	 * See SalvageableService for details.
	 *
	 * @throws MWException If called after MW_SERVICE_BOOTSTRAP_COMPLETE has been defined in
	 *         Setup.php (unless MW_PHPUNIT_TEST or MEDIAWIKI_INSTALL or RUN_MAINTENANCE_IF_MAIN
	 *          is defined).
	 */
	public static function resetGlobalInstance( Config $bootstrapConfig = null, $quick = '' ) {
		if ( self::$instance === null ) {
			// no global instance yet, nothing to reset
			return;
		}

		self::failIfResetNotAllowed( __METHOD__ );

		if ( $bootstrapConfig === null ) {
			$bootstrapConfig = self::$instance->getBootstrapConfig();
		}

		$oldInstance = self::$instance;

		self::$instance = self::newInstance( $bootstrapConfig, 'load' );
		self::$instance->importWiring( $oldInstance, [ 'BootstrapConfig' ] );

		if ( $quick === 'quick' ) {
			self::$instance->salvage( $oldInstance );
		} else {
			$oldInstance->destroy();
		}

	}

	/**
	 * Salvages the state of any salvageable service instances in $other.
	 *
	 * @note $other will have been destroyed when salvage() returns.
	 *
	 * @param MediaWikiServices $other
	 */
	private function salvage( self $other ) {
		foreach ( $this->getServiceNames() as $name ) {
			// The service could be new in the new instance and not registered in the
			// other instance (e.g. an extension that was loaded after the instantiation of
			// the other instance. Skip this service in this case. See T143974
			try {
				$oldService = $other->peekService( $name );
			} catch ( NoSuchServiceException $e ) {
				continue;
			}

			if ( $oldService instanceof SalvageableService ) {
				/** @var SalvageableService $newService */
				$newService = $this->getService( $name );
				$newService->salvage( $oldService );
			}
		}

		$other->destroy();
	}

	/**
	 * 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.
	 *
	 * @param string $loadWiring set this to 'load' to load the wiring files specified
	 *        in the 'ServiceWiringFiles' setting in $bootstrapConfig.
	 *
	 * @return MediaWikiServices
	 * @throws MWException
	 * @throws \FatalError
	 */
	private static function newInstance( Config $bootstrapConfig, $loadWiring = '' ) {
		$instance = new self( $bootstrapConfig );

		// Load the default wiring from the specified files.
		if ( $loadWiring === 'load' ) {
			$wiringFiles = $bootstrapConfig->get( 'ServiceWiringFiles' );
			$instance->loadWiringFiles( $wiringFiles );
		}

		// Provide a traditional hook point to allow extensions to configure services.
		Hooks::run( 'MediaWikiServices', [ $instance ] );

		return $instance;
	}

	/**
	 * 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.
	 *
	 * @since 1.28
	 *
	 * @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 );
		}

		ObjectCache::clear();
	}

	/**
	 * 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.
	 *
	 * @since 1.28
	 *
	 * @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.
	 *
	 * @since 1.28
	 *
	 * @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 bool $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' ) && !defined( 'MW_PARSER_TEST' ) ) {
			throw new MWException( 'resetServiceForTesting() must not be used outside unit tests.' );
		}

		$this->resetService( $name, $destroy );
	}

	/**
	 * Convenience method that throws an exception unless it is called during a phase in which
	 * resetting of global services is allowed. In general, services should not be reset
	 * individually, since that may introduce inconsistencies.
	 *
	 * @since 1.28
	 *
	 * This method will throw an exception if:
	 *
	 * - self::$resetInProgress is false (to allow all services to be reset together
	 *   via resetGlobalInstance)
	 * - and MEDIAWIKI_INSTALL is not defined (to allow services to be reset during installation)
	 * - and MW_PHPUNIT_TEST is not defined (to allow services to be reset during testing)
	 *
	 * 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 have a central place
	 * for managing service bootstrapping and resetting.
	 *
	 * @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 failIfResetNotAllowed( $method ) {
		if ( !defined( 'MW_PHPUNIT_TEST' )
			&& !defined( 'MW_PARSER_TEST' )
			&& !defined( 'MEDIAWIKI_INSTALL' )
			&& !defined( 'RUN_MAINTENANCE_IF_MAIN' )
			&& defined( 'MW_SERVICE_BOOTSTRAP_COMPLETE' )
		) {
			throw new MWException( $method . ' may only be called during bootstrapping and unit tests!' );
		}
	}

	/**
	 * @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'
	 *        service.
	 */
	public function __construct( Config $config ) {
		parent::__construct();

		// 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
	 * and other information that may be needed before the ConfigFactory
	 * service can be instantiated.
	 *
	 * @note This should only be used during bootstrapping, in particular
	 * when creating the MainConfig service. Application logic should
	 * use getMainConfig() to get a Config instances.
	 *
	 * @since 1.27
	 * @return Config
	 */
	public function getBootstrapConfig() {
		return $this->getService( 'BootstrapConfig' );
	}

	/**
	 * @since 1.27
	 * @return ConfigFactory
	 */
	public function getConfigFactory() {
		return $this->getService( 'ConfigFactory' );
	}

	/**
	 * Returns the Config object that provides configuration for MediaWiki core.
	 * This may or may not be the same object that is returned by getBootstrapConfig().
	 *
	 * @since 1.27
	 * @return Config
	 */
	public function getMainConfig() {
		return $this->getService( 'MainConfig' );
	}

	/**
	 * @since 1.27
	 * @return SiteLookup
	 */
	public function getSiteLookup() {
		return $this->getService( 'SiteLookup' );
	}

	/**
	 * @since 1.27
	 * @return SiteStore
	 */
	public function getSiteStore() {
		return $this->getService( 'SiteStore' );
	}

	/**
	 * @since 1.28
	 * @return InterwikiLookup
	 */
	public function getInterwikiLookup() {
		return $this->getService( 'InterwikiLookup' );
	}

	/**
	 * @since 1.27
	 * @return StatsdDataFactory
	 */
	public function getStatsdDataFactory() {
		return $this->getService( 'StatsdDataFactory' );
	}

	/**
	 * @since 1.27
	 * @return EventRelayerGroup
	 */
	public function getEventRelayerGroup() {
		return $this->getService( 'EventRelayerGroup' );
	}

	/**
	 * @since 1.27
	 * @return SearchEngine
	 */
	public function newSearchEngine() {
		// New engine object every time, since they keep state
		return $this->getService( 'SearchEngineFactory' )->create();
	}

	/**
	 * @since 1.27
	 * @return SearchEngineFactory
	 */
	public function getSearchEngineFactory() {
		return $this->getService( 'SearchEngineFactory' );
	}

	/**
	 * @since 1.27
	 * @return SearchEngineConfig
	 */
	public function getSearchEngineConfig() {
		return $this->getService( 'SearchEngineConfig' );
	}

	/**
	 * @since 1.27
	 * @return SkinFactory
	 */
	public function getSkinFactory() {
		return $this->getService( 'SkinFactory' );
	}

	/**
	 * @since 1.28
	 * @return LBFactory
	 */
	public function getDBLoadBalancerFactory() {
		return $this->getService( 'DBLoadBalancerFactory' );
	}

	/**
	 * @since 1.28
	 * @return LoadBalancer The main DB load balancer for the local wiki.
	 */
	public function getDBLoadBalancer() {
		return $this->getService( 'DBLoadBalancer' );
	}

	/**
	 * @since 1.28
	 * @return WatchedItemStore
	 */
	public function getWatchedItemStore() {
		return $this->getService( 'WatchedItemStore' );
	}

	/**
	 * @since 1.28
	 * @return WatchedItemQueryService
	 */
	public function getWatchedItemQueryService() {
		return $this->getService( 'WatchedItemQueryService' );
	}

	/**
	 * @since 1.28
	 * @return CryptRand
	 */
	public function getCryptRand() {
		return $this->getService( 'CryptRand' );
	}

	/**
	 * @since 1.28
	 * @return CryptHKDF
	 */
	public function getCryptHKDF() {
		return $this->getService( 'CryptHKDF' );
	}

	/**
	 * @since 1.28
	 * @return MediaHandlerFactory
	 */
	public function getMediaHandlerFactory() {
		return $this->getService( 'MediaHandlerFactory' );
	}

	/**
	 * @since 1.28
	 * @return MimeAnalyzer
	 */
	public function getMimeAnalyzer() {
		return $this->getService( 'MimeAnalyzer' );
	}

	/**
	 * @since 1.28
	 * @return ProxyLookup
	 */
	public function getProxyLookup() {
		return $this->getService( 'ProxyLookup' );
	}

	/**
	 * @since 1.28
	 * @return Parser
	 */
	public function getParser() {
		return $this->getService( 'Parser' );
	}

	/**
	 * @since 1.28
	 * @return GenderCache
	 */
	public function getGenderCache() {
		return $this->getService( 'GenderCache' );
	}

	/**
	 * @since 1.28
	 * @return LinkCache
	 */
	public function getLinkCache() {
		return $this->getService( 'LinkCache' );
	}

	/**
	 * @since 1.28
	 * @return LinkRendererFactory
	 */
	public function getLinkRendererFactory() {
		return $this->getService( 'LinkRendererFactory' );
	}

	/**
	 * LinkRenderer instance that can be used
	 * if no custom options are needed
	 *
	 * @since 1.28
	 * @return LinkRenderer
	 */
	public function getLinkRenderer() {
		return $this->getService( 'LinkRenderer' );
	}

	/**
	 * @since 1.28
	 * @return TitleFormatter
	 */
	public function getTitleFormatter() {
		return $this->getService( 'TitleFormatter' );
	}

	/**
	 * @since 1.28
	 * @return TitleParser
	 */
	public function getTitleParser() {
		return $this->getService( 'TitleParser' );
	}

	/**
	 * @since 1.28
	 * @return \BagOStuff
	 */
	public function getMainObjectStash() {
		return $this->getService( 'MainObjectStash' );
	}

	/**
	 * @since 1.28
	 * @return \WANObjectCache
	 */
	public function getMainWANObjectCache() {
		return $this->getService( 'MainWANObjectCache' );
	}

	/**
	 * @since 1.28
	 * @return \BagOStuff
	 */
	public function getLocalServerObjectCache() {
		return $this->getService( 'LocalServerObjectCache' );
	}

	/**
	 * @since 1.28
	 * @return VirtualRESTServiceClient
	 */
	public function getVirtualRESTServiceClient() {
		return $this->getService( 'VirtualRESTServiceClient' );
	}

	///////////////////////////////////////////////////////////////////////////
	// NOTE: When adding a service getter here, don't forget to add a test
	// case for it in MediaWikiServicesTest::provideGetters() and in
	// MediaWikiServicesTest::provideGetService()!
	///////////////////////////////////////////////////////////////////////////

}


1		<?php
2		namespace MediaWiki;
3
4		use Config;
5		use ConfigFactory;
6		use CryptHKDF;
7		use CryptRand;
8		use EventRelayerGroup;
9		use GenderCache;
10		use GlobalVarConfig;
11		use Hooks;
12		use LBFactory;
13		use LinkCache;
14		use Liuggio\StatsdClient\Factory\StatsdDataFactory;
15		use LoadBalancer;
16		use MediaHandlerFactory;
17		use MediaWiki\Linker\LinkRenderer;
18		use MediaWiki\Linker\LinkRendererFactory;
19		use MediaWiki\Services\SalvageableService;
20		use MediaWiki\Services\ServiceContainer;
21		use MediaWiki\Services\NoSuchServiceException;
22		use MWException;
23		use MimeAnalyzer;
24		use ObjectCache;
25		use Parser;
26		use ProxyLookup;
27		use SearchEngine;
28		use SearchEngineConfig;
29		use SearchEngineFactory;
30		use SiteLookup;
31		use SiteStore;
32		use WatchedItemStore;
33		use WatchedItemQueryService;
34		use SkinFactory;
35		use TitleFormatter;
36		use TitleParser;
37		use VirtualRESTServiceClient;
38		use MediaWiki\Interwiki\InterwikiLookup;
39
40		/**
41		* Service locator for MediaWiki core services.
42		*
43		* This program is free software; you can redistribute it and/or modify
44		* it under the terms of the GNU General Public License as published by
45		* the Free Software Foundation; either version 2 of the License, or
46		* (at your option) any later version.
47		*
48		* This program is distributed in the hope that it will be useful,
49		* but WITHOUT ANY WARRANTY; without even the implied warranty of
50		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
51		* GNU General Public License for more details.
52		*
53		* You should have received a copy of the GNU General Public License along
54		* with this program; if not, write to the Free Software Foundation, Inc.,
55		* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
56		* http://www.gnu.org/copyleft/gpl.html
57		*
58		* @file
59		*
60		* @since 1.27
61		*/
62
63		/**
64		* MediaWikiServices is the service locator for the application scope of MediaWiki.
65		* Its implemented as a simple configurable DI container.
66		* MediaWikiServices acts as a top level factory/registry for top level services, and builds
67		* the network of service objects that defines MediaWiki's application logic.
68		* It acts as an entry point to MediaWiki's dependency injection mechanism.
69		*
70		* Services are defined in the "wiring" array passed to the constructor,
71		* or by calling defineService().
72		*
73		* @see docs/injection.txt for an overview of using dependency injection in the
74		* MediaWiki code base.
75		*/
76		class MediaWikiServices extends ServiceContainer {
77
78		/**
79		* @var MediaWikiServices\|null
80		*/
81		private static $instance = null;
82
83		/**
84		* Returns the global default instance of the top level service locator.
85		*
86		* @since 1.27
87		*
88		* The default instance is initialized using the service instantiator functions
89		* defined in ServiceWiring.php.
90		*
91		* @note This should only be called by static functions! The instance returned here
92		* should not be passed around! Objects that need access to a service should have
93		* that service injected into the constructor, never a service locator!
94		*
95		* @return MediaWikiServices
96		*/
97		public static function getInstance() {
98		if ( self::$instance === null ) {
99		// NOTE: constructing GlobalVarConfig here is not particularly pretty,
100		// but some information from the global scope has to be injected here,
101		// even if it's just a file name or database credentials to load
102		// configuration from.
103		$bootstrapConfig = new GlobalVarConfig();
104		self::$instance = self::newInstance( $bootstrapConfig, 'load' );
105		}
106
107		return self::$instance;
108		}
109
110		/**
111		* Replaces the global MediaWikiServices instance.
112		*
113		* @since 1.28
114		*
115		* @note This is for use in PHPUnit tests only!
116		*
117		* @throws MWException if called outside of PHPUnit tests.
118		*
119		* @param MediaWikiServices $services The new MediaWikiServices object.
120		*
121		* @return MediaWikiServices The old MediaWikiServices object, so it can be restored later.
122		*/
123		public static function forceGlobalInstance( MediaWikiServices $services ) {
124		if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
125		throw new MWException( __METHOD__ . ' must not be used outside unit tests.' );
126		}
127
128		$old = self::getInstance();
129		self::$instance = $services;
130
131		return $old;
132		}
133
134		/**
135		* Creates a new instance of MediaWikiServices and sets it as the global default
136		* instance. getInstance() will return a different MediaWikiServices object
137		* after every call to resetGlobalInstance().
138		*
139		* @since 1.28
140		*
141		* @warning This should not be used during normal operation. It is intended for use
142		* when the configuration has changed significantly since bootstrap time, e.g.
143		* during the installation process or during testing.
144		*
145		* @warning Calling resetGlobalInstance() may leave the application in an inconsistent
146		* state. Calling this is only safe under the ASSUMPTION that NO REFERENCE to
147		* any of the services managed by MediaWikiServices exist. If any service objects
148		* managed by the old MediaWikiServices instance remain in use, they may INTERFERE
149		* with the operation of the services managed by the new MediaWikiServices.
150		* Operating with a mix of services created by the old and the new
151		* MediaWikiServices instance may lead to INCONSISTENCIES and even DATA LOSS!
152		* Any class implementing LAZY LOADING is especially prone to this problem,
153		* since instances would typically retain a reference to a storage layer service.
154		*
155		* @see forceGlobalInstance()
156		* @see resetGlobalInstance()
157		* @see resetBetweenTest()
158		*
159		* @param Config\|null $bootstrapConfig The Config object to be registered as the
160		* 'BootstrapConfig' service. This has to contain at least the information
161		* needed to set up the 'ConfigFactory' service. If not given, the bootstrap
162		* config of the old instance of MediaWikiServices will be re-used. If there
163		* was no previous instance, a new GlobalVarConfig object will be used to
164		* bootstrap the services.
165		*
166		* @param string $quick Set this to "quick" to allow expensive resources to be re-used.
167		* See SalvageableService for details.
168		*
169		* @throws MWException If called after MW_SERVICE_BOOTSTRAP_COMPLETE has been defined in
170		* Setup.php (unless MW_PHPUNIT_TEST or MEDIAWIKI_INSTALL or RUN_MAINTENANCE_IF_MAIN
171		* is defined).
172		*/
173		public static function resetGlobalInstance( Config $bootstrapConfig = null, $quick = '' ) {
174		if ( self::$instance === null ) {
175		// no global instance yet, nothing to reset
176		return;
177		}
178
179		self::failIfResetNotAllowed( __METHOD__ );
180
181		if ( $bootstrapConfig === null ) {
182		$bootstrapConfig = self::$instance->getBootstrapConfig();
183		}
184
185		$oldInstance = self::$instance;
186
187		self::$instance = self::newInstance( $bootstrapConfig, 'load' );
188		self::$instance->importWiring( $oldInstance, [ 'BootstrapConfig' ] );
189
190		if ( $quick === 'quick' ) {
191		self::$instance->salvage( $oldInstance );
192		} else {
193		$oldInstance->destroy();
194		}
195
196		}
197
198		/**
199		* Salvages the state of any salvageable service instances in $other.
200		*
201		* @note $other will have been destroyed when salvage() returns.
202		*
203		* @param MediaWikiServices $other
204		*/
205		private function salvage( self $other ) {
206		foreach ( $this->getServiceNames() as $name ) {
207		// The service could be new in the new instance and not registered in the
208		// other instance (e.g. an extension that was loaded after the instantiation of
209		// the other instance. Skip this service in this case. See T143974
210		try {
211		$oldService = $other->peekService( $name );
212		} catch ( NoSuchServiceException $e ) {
213		continue;
214		}
215
216		if ( $oldService instanceof SalvageableService ) {
217		/** @var SalvageableService $newService */
218		$newService = $this->getService( $name );
219		$newService->salvage( $oldService );
220		}
221		}
222
223		$other->destroy();
224		}
225
226		/**
227		* Creates a new MediaWikiServices instance and initializes it according to the
228		* given $bootstrapConfig. In particular, all wiring files defined in the
229		* ServiceWiringFiles setting are loaded, and the MediaWikiServices hook is called.
230		*
231		* @param Config\|null $bootstrapConfig The Config object to be registered as the
232		* 'BootstrapConfig' service.
233		*
234		* @param string $loadWiring set this to 'load' to load the wiring files specified
235		* in the 'ServiceWiringFiles' setting in $bootstrapConfig.
236		*
237		* @return MediaWikiServices
238		* @throws MWException
239		* @throws \FatalError
240		*/
241		private static function newInstance( Config $bootstrapConfig, $loadWiring = '' ) {
242		$instance = new self( $bootstrapConfig );
243
244		// Load the default wiring from the specified files.
245		if ( $loadWiring === 'load' ) {
246		$wiringFiles = $bootstrapConfig->get( 'ServiceWiringFiles' );
247		$instance->loadWiringFiles( $wiringFiles );
248		}
249
250		// Provide a traditional hook point to allow extensions to configure services.
251		Hooks::run( 'MediaWikiServices', [ $instance ] );
252
253		return $instance;
254		}
255
256		/**
257		* Disables all storage layer services. After calling this, any attempt to access the
258		* storage layer will result in an error. Use resetGlobalInstance() to restore normal
259		* operation.
260		*
261		* @since 1.28
262		*
263		* @warning This is intended for extreme situations only and should never be used
264		* while serving normal web requests. Legitimate use cases for this method include
265		* the installation process. Test fixtures may also use this, if the fixture relies
266		* on globalState.
267		*
268		* @see resetGlobalInstance()
269		* @see resetChildProcessServices()
270		*/
271		public static function disableStorageBackend() {
272		// TODO: also disable some Caches, JobQueues, etc
273		$destroy = [ 'DBLoadBalancer', 'DBLoadBalancerFactory' ];
274		$services = self::getInstance();
275
276		foreach ( $destroy as $name ) {
277		$services->disableService( $name );
278		}
279
280		ObjectCache::clear();
281		}
282
283		/**
284		* Resets any services that may have become stale after a child process
285		* returns from after pcntl_fork(). It's also safe, but generally unnecessary,
286		* to call this method from the parent process.
287		*
288		* @since 1.28
289		*
290		* @note This is intended for use in the context of process forking only!
291		*
292		* @see resetGlobalInstance()
293		* @see disableStorageBackend()
294		*/
295		public static function resetChildProcessServices() {
296		// NOTE: for now, just reset everything. Since we don't know the interdependencies
297		// between services, we can't do this more selectively at this time.
298		self::resetGlobalInstance();
299
300		// Child, reseed because there is no bug in PHP:
301		// http://bugs.php.net/bug.php?id=42465
302		mt_srand( getmypid() );
303		}
304
305		/**
306		* Resets the given service for testing purposes.
307		*
308		* @since 1.28
309		*
310		* @warning This is generally unsafe! Other services may still retain references
311		* to the stale service instance, leading to failures and inconsistencies. Subclasses
312		* may use this method to reset specific services under specific instances, but
313		* it should not be exposed to application logic.
314		*
315		* @note With proper dependency injection used throughout the codebase, this method
316		* should not be needed. It is provided to allow tests that pollute global service
317		* instances to clean up.
318		*
319		* @param string $name
320		* @param bool $destroy Whether the service instance should be destroyed if it exists.
321		* When set to false, any existing service instance will effectively be detached
322		* from the container.
323		*
324		* @throws MWException if called outside of PHPUnit tests.
325		*/
326	View Code Duplication	public function resetServiceForTesting( $name, $destroy = true ) {
327		if ( !defined( 'MW_PHPUNIT_TEST' ) && !defined( 'MW_PARSER_TEST' ) ) {
328		throw new MWException( 'resetServiceForTesting() must not be used outside unit tests.' );
329		}
330
331		$this->resetService( $name, $destroy );
332		}
333
334		/**
335		* Convenience method that throws an exception unless it is called during a phase in which
336		* resetting of global services is allowed. In general, services should not be reset
337		* individually, since that may introduce inconsistencies.
338		*
339		* @since 1.28
340		*
341		* This method will throw an exception if:
342		*
343		* - self::$resetInProgress is false (to allow all services to be reset together
344		* via resetGlobalInstance)
345		* - and MEDIAWIKI_INSTALL is not defined (to allow services to be reset during installation)
346		* - and MW_PHPUNIT_TEST is not defined (to allow services to be reset during testing)
347		*
348		* This method is intended to be used to safeguard against accidentally resetting
349		* global service instances that are not yet managed by MediaWikiServices. It is
350		* defined here in the MediaWikiServices services class to have a central place
351		* for managing service bootstrapping and resetting.
352		*
353		* @param string $method the name of the caller method, as given by __METHOD__.
354		*
355		* @throws MWException if called outside bootstrap mode.
356		*
357		* @see resetGlobalInstance()
358		* @see forceGlobalInstance()
359		* @see disableStorageBackend()
360		*/
361		public static function failIfResetNotAllowed( $method ) {
362		if ( !defined( 'MW_PHPUNIT_TEST' )
363		&& !defined( 'MW_PARSER_TEST' )
364		&& !defined( 'MEDIAWIKI_INSTALL' )
365		&& !defined( 'RUN_MAINTENANCE_IF_MAIN' )
366		&& defined( 'MW_SERVICE_BOOTSTRAP_COMPLETE' )
367		) {
368		throw new MWException( $method . ' may only be called during bootstrapping and unit tests!' );
369		}
370		}
371
372		/**
373		* @param Config $config The Config object to be registered as the 'BootstrapConfig' service.
374		* This has to contain at least the information needed to set up the 'ConfigFactory'
375		* service.
376		*/
377		public function __construct( Config $config ) {
378		parent::__construct();
379
380		// Register the given Config object as the bootstrap config service.
381		$this->defineService( 'BootstrapConfig', function() use ( $config ) {
382		return $config;
383		} );
384		}
385
386		// CONVENIENCE GETTERS ////////////////////////////////////////////////////
387
388		/**
389		* Returns the Config object containing the bootstrap configuration.
390		* Bootstrap configuration would typically include database credentials
391		* and other information that may be needed before the ConfigFactory
392		* service can be instantiated.
393		*
394		* @note This should only be used during bootstrapping, in particular
395		* when creating the MainConfig service. Application logic should
396		* use getMainConfig() to get a Config instances.
397		*
398		* @since 1.27
399		* @return Config
400		*/
401		public function getBootstrapConfig() {
402		return $this->getService( 'BootstrapConfig' );
403		}
404
405		/**
406		* @since 1.27
407		* @return ConfigFactory
408		*/
409		public function getConfigFactory() {
410		return $this->getService( 'ConfigFactory' );
411		}
412
413		/**
414		* Returns the Config object that provides configuration for MediaWiki core.
415		* This may or may not be the same object that is returned by getBootstrapConfig().
416		*
417		* @since 1.27
418		* @return Config
419		*/
420		public function getMainConfig() {
421		return $this->getService( 'MainConfig' );
422		}
423
424		/**
425		* @since 1.27
426		* @return SiteLookup
427		*/
428		public function getSiteLookup() {
429		return $this->getService( 'SiteLookup' );
430		}
431
432		/**
433		* @since 1.27
434		* @return SiteStore
435		*/
436		public function getSiteStore() {
437		return $this->getService( 'SiteStore' );
438		}
439
440		/**
441		* @since 1.28
442		* @return InterwikiLookup
443		*/
444		public function getInterwikiLookup() {
445		return $this->getService( 'InterwikiLookup' );
446		}
447
448		/**
449		* @since 1.27
450		* @return StatsdDataFactory
451		*/
452		public function getStatsdDataFactory() {
453		return $this->getService( 'StatsdDataFactory' );
454		}
455
456		/**
457		* @since 1.27
458		* @return EventRelayerGroup
459		*/
460		public function getEventRelayerGroup() {
461		return $this->getService( 'EventRelayerGroup' );
462		}
463
464		/**
465		* @since 1.27
466		* @return SearchEngine
467		*/
468		public function newSearchEngine() {
469		// New engine object every time, since they keep state
470		return $this->getService( 'SearchEngineFactory' )->create();
471		}
472
473		/**
474		* @since 1.27
475		* @return SearchEngineFactory
476		*/
477		public function getSearchEngineFactory() {
478		return $this->getService( 'SearchEngineFactory' );
479		}
480
481		/**
482		* @since 1.27
483		* @return SearchEngineConfig
484		*/
485		public function getSearchEngineConfig() {
486		return $this->getService( 'SearchEngineConfig' );
487		}
488
489		/**
490		* @since 1.27
491		* @return SkinFactory
492		*/
493		public function getSkinFactory() {
494		return $this->getService( 'SkinFactory' );
495		}
496
497		/**
498		* @since 1.28
499		* @return LBFactory
500		*/
501		public function getDBLoadBalancerFactory() {
502		return $this->getService( 'DBLoadBalancerFactory' );
503		}
504
505		/**
506		* @since 1.28
507		* @return LoadBalancer The main DB load balancer for the local wiki.
508		*/
509		public function getDBLoadBalancer() {
510		return $this->getService( 'DBLoadBalancer' );
511		}
512
513		/**
514		* @since 1.28
515		* @return WatchedItemStore
516		*/
517		public function getWatchedItemStore() {
518		return $this->getService( 'WatchedItemStore' );
519		}
520
521		/**
522		* @since 1.28
523		* @return WatchedItemQueryService
524		*/
525		public function getWatchedItemQueryService() {
526		return $this->getService( 'WatchedItemQueryService' );
527		}
528
529		/**
530		* @since 1.28
531		* @return CryptRand
532		*/
533		public function getCryptRand() {
534		return $this->getService( 'CryptRand' );
535		}
536
537		/**
538		* @since 1.28
539		* @return CryptHKDF
540		*/
541		public function getCryptHKDF() {
542		return $this->getService( 'CryptHKDF' );
543		}
544
545		/**
546		* @since 1.28
547		* @return MediaHandlerFactory
548		*/
549		public function getMediaHandlerFactory() {
550		return $this->getService( 'MediaHandlerFactory' );
551		}
552
553		/**
554		* @since 1.28
555		* @return MimeAnalyzer
556		*/
557		public function getMimeAnalyzer() {
558		return $this->getService( 'MimeAnalyzer' );
559		}
560
561		/**
562		* @since 1.28
563		* @return ProxyLookup
564		*/
565		public function getProxyLookup() {
566		return $this->getService( 'ProxyLookup' );
567		}
568
569		/**
570		* @since 1.28
571		* @return Parser
572		*/
573		public function getParser() {
574		return $this->getService( 'Parser' );
575		}
576
577		/**
578		* @since 1.28
579		* @return GenderCache
580		*/
581		public function getGenderCache() {
582		return $this->getService( 'GenderCache' );
583		}
584
585		/**
586		* @since 1.28
587		* @return LinkCache
588		*/
589		public function getLinkCache() {
590		return $this->getService( 'LinkCache' );
591		}
592
593		/**
594		* @since 1.28
595		* @return LinkRendererFactory
596		*/
597		public function getLinkRendererFactory() {
598		return $this->getService( 'LinkRendererFactory' );
599		}
600
601		/**
602		* LinkRenderer instance that can be used
603		* if no custom options are needed
604		*
605		* @since 1.28
606		* @return LinkRenderer
607		*/
608		public function getLinkRenderer() {
609		return $this->getService( 'LinkRenderer' );
610		}
611
612		/**
613		* @since 1.28
614		* @return TitleFormatter
615		*/
616		public function getTitleFormatter() {
617		return $this->getService( 'TitleFormatter' );
618		}
619
620		/**
621		* @since 1.28
622		* @return TitleParser
623		*/
624		public function getTitleParser() {
625		return $this->getService( 'TitleParser' );
626		}
627
628		/**
629		* @since 1.28
630		* @return \BagOStuff
631		*/
632		public function getMainObjectStash() {
633		return $this->getService( 'MainObjectStash' );
634		}
635
636		/**
637		* @since 1.28
638		* @return \WANObjectCache
639		*/
640		public function getMainWANObjectCache() {
641		return $this->getService( 'MainWANObjectCache' );
642		}
643
644		/**
645		* @since 1.28
646		* @return \BagOStuff
647		*/
648		public function getLocalServerObjectCache() {
649		return $this->getService( 'LocalServerObjectCache' );
650		}
651
652		/**
653		* @since 1.28
654		* @return VirtualRESTServiceClient
655		*/
656		public function getVirtualRESTServiceClient() {
657		return $this->getService( 'VirtualRESTServiceClient' );
658		}
659
660		///////////////////////////////////////////////////////////////////////////
661		// NOTE: When adding a service getter here, don't forget to add a test
662		// case for it in MediaWikiServicesTest::provideGetters() and in
663		// MediaWikiServicesTest::provideGetService()!
664		///////////////////////////////////////////////////////////////////////////
665
666		}
667

wikimedia / mediawiki

Branch — master (9ca75b)

MediaWikiServices::newSearchEngine() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like