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class Drupal in Drupal 9

Same name and namespace in other branches
  1. 8 core/lib/Drupal.php \Drupal

Static Service Container wrapper.

Generally, code in Drupal should accept its dependencies via either constructor injection or setter method injection. However, there are cases, particularly in legacy procedural code, where that is infeasible. This class acts as a unified global accessor to arbitrary services within the system in order to ease the transition from procedural code to injected OO code.

The container is built by the kernel and passed in to this class which stores it statically. The container always contains the services from \Drupal\Core\CoreServiceProvider, the service providers of enabled modules and any other service providers defined in $GLOBALS['conf']['container_service_providers'].

This class exists only to support legacy code that cannot be dependency injected. If your code needs it, consider refactoring it to be object oriented, if possible. When this is not possible, for instance in the case of hook implementations, and your code is more than a few non-reusable lines, it is recommended to instantiate an object implementing the actual logic.

// Legacy procedural code.
function hook_do_stuff() {
  $lock = lock()
    ->acquire('stuff_lock');

  // ...
}

// Correct procedural code.
function hook_do_stuff() {
  $lock = \Drupal::lock()
    ->acquire('stuff_lock');

  // ...
}

// The preferred way: dependency injected code.
function hook_do_stuff() {

  // Move the actual implementation to a class and instantiate it.
  $instance = new StuffDoingClass(\Drupal::lock());
  $instance
    ->doStuff();

  // Or, even better, rely on the service container to avoid hard coding a
  // specific interface implementation, so that the actual logic can be
  // swapped. This might not always make sense, but in general it is a good
  // practice.
  \Drupal::service('stuff.doing')
    ->doStuff();
}
interface StuffDoingInterface {
  public function doStuff();

}
class StuffDoingClass implements StuffDoingInterface {
  protected $lockBackend;
  public function __construct(LockBackendInterface $lock_backend) {
    $this->lockBackend = $lock_backend;
  }
  public function doStuff() {
    $lock = $this->lockBackend
      ->acquire('stuff_lock');

    // ...
  }

}

Hierarchy

Expanded class hierarchy of Drupal

See also

\Drupal\Core\DrupalKernel

36 string references to 'Drupal'
common_test_drupal_alter_alter in core/modules/system/tests/modules/common_test/common_test.module
Implements hook_TYPE_alter().
ConfigAccessTest::testBlockConfigAccess in core/modules/settings_tray/tests/src/FunctionalJavascript/ConfigAccessTest.php
Tests access to block forms with related configuration is correct.
ConfigFormOverrideTest::testFormsWithOverrides in core/modules/config/tests/src/Functional/ConfigFormOverrideTest.php
Tests that overrides do not affect forms.
ConfigInstallProfileOverrideTest::testInstallProfileConfigOverwrite in core/modules/config/tests/src/Functional/ConfigInstallProfileOverrideTest.php
Tests install profile config changes.
ConfigNamesMapperTest::testGetConfigData in core/modules/config_translation/tests/src/Unit/ConfigNamesMapperTest.php
Tests ConfigNamesMapper::getConfigData().

... See full list

File

core/lib/Drupal.php, line 73

View source 
class Drupal {

  /**
   * The current system version.
   */
  const VERSION = '9.3.0-dev';

  /**
   * Core API compatibility.
   */
  const CORE_COMPATIBILITY = '8.x';

  /**
   * Core minimum schema version.
   */
  const CORE_MINIMUM_SCHEMA_VERSION = 8000;

  /**
   * Minimum supported version of PHP.
   *
   * Below this version:
   * - New sites cannot be installed, except from within tests.
   * - Updates from previous Drupal versions can be run, but users are warned
   *   that Drupal no longer supports that PHP version.
   * - An error is shown in the status report that the PHP version is too old.
   */
  const MINIMUM_SUPPORTED_PHP = '7.3.0';

  /**
   * Minimum allowed version of PHP for Drupal to be bootstrapped.
   *
   * Below this version:
   * - The installer cannot be run.
   * - Updates cannot be run.
   * - Modules and themes cannot be enabled.
   * - If a site managed to bypass all of the above, then an error is shown in
   *   the status report and various fatal errors occur on various pages.
   *
   * Note: To prevent the installer from having fatal errors on older versions
   * of PHP, the value of this constant is hardcoded twice in core/install.php:
   * - Once as a parameter of version_compare()
   * - Once in the error message printed to the user immediately after.
   * Remember to update both whenever this constant is updated.
   */
  const MINIMUM_PHP = '7.3.0';

  /**
   * Minimum recommended value of PHP memory_limit.
   *
   * 64M was chosen as a minimum requirement in order to allow for additional
   * contributed modules to be installed prior to hitting the limit. However,
   * 40M is the target for the Standard installation profile.
   */
  const MINIMUM_PHP_MEMORY_LIMIT = '64M';

  /**
   * Minimum recommended version of PHP.
   *
   * Sites installing Drupal on PHP versions lower than this will see a warning
   * message, but Drupal can still be installed. Used for (e.g.) PHP versions
   * that have reached their EOL or will in the near future.
   */
  const RECOMMENDED_PHP = '7.4';

  /**
   * The currently active container object, or NULL if not initialized yet.
   *
   * @var \Symfony\Component\DependencyInjection\ContainerInterface|null
   */
  protected static $container;

  /**
   * Sets a new global container.
   *
   * @param \Symfony\Component\DependencyInjection\ContainerInterface $container
   *   A new container instance to replace the current.
   */
  public static function setContainer(ContainerInterface $container) {
    static::$container = $container;
  }

  /**
   * Unsets the global container.
   */
  public static function unsetContainer() {
    static::$container = NULL;
  }

  /**
   * Returns the currently active global container.
   *
   * @return \Symfony\Component\DependencyInjection\ContainerInterface
   *
   * @throws \Drupal\Core\DependencyInjection\ContainerNotInitializedException
   */
  public static function getContainer() {
    if (static::$container === NULL) {
      throw new ContainerNotInitializedException('\\Drupal::$container is not initialized yet. \\Drupal::setContainer() must be called with a real container.');
    }
    return static::$container;
  }

  /**
   * Returns TRUE if the container has been initialized, FALSE otherwise.
   *
   * @return bool
   */
  public static function hasContainer() {
    return static::$container !== NULL;
  }

  /**
   * Retrieves a service from the container.
   *
   * Use this method if the desired service is not one of those with a dedicated
   * accessor method below. If it is listed below, those methods are preferred
   * as they can return useful type hints.
   *
   * @param string $id
   *   The ID of the service to retrieve.
   *
   * @return mixed
   *   The specified service.
   */
  public static function service($id) {
    return static::getContainer()
      ->get($id);
  }

  /**
   * Indicates if a service is defined in the container.
   *
   * @param string $id
   *   The ID of the service to check.
   *
   * @return bool
   *   TRUE if the specified service exists, FALSE otherwise.
   */
  public static function hasService($id) {

    // Check hasContainer() first in order to always return a Boolean.
    return static::hasContainer() && static::getContainer()
      ->has($id);
  }

  /**
   * Gets the app root.
   *
   * @return string
   */
  public static function root() {
    return static::getContainer()
      ->getParameter('app.root');
  }

  /**
   * Gets the active install profile.
   *
   * @return string|null
   *   The name of the active install profile.
   */
  public static function installProfile() {
    return static::getContainer()
      ->getParameter('install_profile');
  }

  /**
   * Indicates if there is a currently active request object.
   *
   * @return bool
   *   TRUE if there is a currently active request object, FALSE otherwise.
   */
  public static function hasRequest() {

    // Check hasContainer() first in order to always return a Boolean.
    return static::hasContainer() && static::getContainer()
      ->has('request_stack') && static::getContainer()
      ->get('request_stack')
      ->getCurrentRequest() !== NULL;
  }

  /**
   * Retrieves the currently active request object.
   *
   * Note: The use of this wrapper in particular is especially discouraged. Most
   * code should not need to access the request directly.  Doing so means it
   * will only function when handling an HTTP request, and will require special
   * modification or wrapping when run from a command line tool, from certain
   * queue processors, or from automated tests.
   *
   * If code must access the request, it is considerably better to register
   * an object with the Service Container and give it a setRequest() method
   * that is configured to run when the service is created.  That way, the
   * correct request object can always be provided by the container and the
   * service can still be unit tested.
   *
   * If this method must be used, never save the request object that is
   * returned.  Doing so may lead to inconsistencies as the request object is
   * volatile and may change at various times, such as during a subrequest.
   *
   * @return \Symfony\Component\HttpFoundation\Request
   *   The currently active request object.
   */
  public static function request() {
    return static::getContainer()
      ->get('request_stack')
      ->getCurrentRequest();
  }

  /**
   * Retrieves the request stack.
   *
   * @return \Symfony\Component\HttpFoundation\RequestStack
   *   The request stack
   */
  public static function requestStack() {
    return static::getContainer()
      ->get('request_stack');
  }

  /**
   * Retrieves the currently active route match object.
   *
   * @return \Drupal\Core\Routing\RouteMatchInterface
   *   The currently active route match object.
   */
  public static function routeMatch() {
    return static::getContainer()
      ->get('current_route_match');
  }

  /**
   * Gets the current active user.
   *
   * This method will return the \Drupal\Core\Session\AccountProxy object of the
   * current user. You can use the \Drupal\user\Entity\User::load() method to
   * load the full user entity object. For example:
   * @code
   *   $user = \Drupal\user\Entity\User::load(\Drupal::currentUser()->id());
   * @endcode
   *
   * @return \Drupal\Core\Session\AccountProxyInterface
   */
  public static function currentUser() {
    return static::getContainer()
      ->get('current_user');
  }

  /**
   * Retrieves the entity type manager.
   *
   * @return \Drupal\Core\Entity\EntityTypeManagerInterface
   *   The entity type manager.
   */
  public static function entityTypeManager() {
    return static::getContainer()
      ->get('entity_type.manager');
  }

  /**
   * Returns the current primary database.
   *
   * @return \Drupal\Core\Database\Connection
   *   The current active database's master connection.
   */
  public static function database() {
    return static::getContainer()
      ->get('database');
  }

  /**
   * Returns the requested cache bin.
   *
   * @param string $bin
   *   (optional) The cache bin for which the cache object should be returned,
   *   defaults to 'default'.
   *
   * @return \Drupal\Core\Cache\CacheBackendInterface
   *   The cache object associated with the specified bin.
   *
   * @ingroup cache
   */
  public static function cache($bin = 'default') {
    return static::getContainer()
      ->get('cache.' . $bin);
  }

  /**
   * Retrieves the class resolver.
   *
   * This is to be used in procedural code such as module files to instantiate
   * an object of a class that implements
   * \Drupal\Core\DependencyInjection\ContainerInjectionInterface.
   *
   * One common usecase is to provide a class which contains the actual code
   * of a hook implementation, without having to create a service.
   *
   * @param string $class
   *   (optional) A class name to instantiate.
   *
   * @return \Drupal\Core\DependencyInjection\ClassResolverInterface|object
   *   The class resolver or if $class is provided, a class instance with a
   *   given class definition.
   *
   * @throws \InvalidArgumentException
   *   If $class does not exist.
   */
  public static function classResolver($class = NULL) {
    if ($class) {
      return static::getContainer()
        ->get('class_resolver')
        ->getInstanceFromDefinition($class);
    }
    return static::getContainer()
      ->get('class_resolver');
  }

  /**
   * Returns an expirable key value store collection.
   *
   * @param string $collection
   *   The name of the collection holding key and value pairs.
   *
   * @return \Drupal\Core\KeyValueStore\KeyValueStoreExpirableInterface
   *   An expirable key value store collection.
   */
  public static function keyValueExpirable($collection) {
    return static::getContainer()
      ->get('keyvalue.expirable')
      ->get($collection);
  }

  /**
   * Returns the locking layer instance.
   *
   * @return \Drupal\Core\Lock\LockBackendInterface
   *
   * @ingroup lock
   */
  public static function lock() {
    return static::getContainer()
      ->get('lock');
  }

  /**
   * Retrieves a configuration object.
   *
   * This is the main entry point to the configuration API. Calling
   * @code \Drupal::config('book.admin') @endcode will return a configuration
   * object the Book module can use to read its administrative settings.
   *
   * @param string $name
   *   The name of the configuration object to retrieve, which typically
   *   corresponds to a configuration file. For
   *   @code \Drupal::config('book.admin') @endcode, the configuration
   *   object returned will contain the content of the book.admin
   *   configuration file.
   *
   * @return \Drupal\Core\Config\ImmutableConfig
   *   An immutable configuration object.
   */
  public static function config($name) {
    return static::getContainer()
      ->get('config.factory')
      ->get($name);
  }

  /**
   * Retrieves the configuration factory.
   *
   * This is mostly used to change the override settings on the configuration
   * factory. For example, changing the language, or turning all overrides on
   * or off.
   *
   * @return \Drupal\Core\Config\ConfigFactoryInterface
   *   The configuration factory service.
   */
  public static function configFactory() {
    return static::getContainer()
      ->get('config.factory');
  }

  /**
   * Returns a queue for the given queue name.
   *
   * The following values can be set in your settings.php file's $settings
   * array to define which services are used for queues:
   * - queue_reliable_service_$name: The container service to use for the
   *   reliable queue $name.
   * - queue_service_$name: The container service to use for the
   *   queue $name.
   * - queue_default: The container service to use by default for queues
   *   without overrides. This defaults to 'queue.database'.
   *
   * @param string $name
   *   The name of the queue to work with.
   * @param bool $reliable
   *   (optional) TRUE if the ordering of items and guaranteeing every item
   *   executes at least once is important, FALSE if scalability is the main
   *   concern. Defaults to FALSE.
   *
   * @return \Drupal\Core\Queue\QueueInterface
   *   The queue object for a given name.
   */
  public static function queue($name, $reliable = FALSE) {
    return static::getContainer()
      ->get('queue')
      ->get($name, $reliable);
  }

  /**
   * Returns a key/value storage collection.
   *
   * @param string $collection
   *   Name of the key/value collection to return.
   *
   * @return \Drupal\Core\KeyValueStore\KeyValueStoreInterface
   */
  public static function keyValue($collection) {
    return static::getContainer()
      ->get('keyvalue')
      ->get($collection);
  }

  /**
   * Returns the state storage service.
   *
   * Use this to store machine-generated data, local to a specific environment
   * that does not need deploying and does not need human editing; for example,
   * the last time cron was run. Data which needs to be edited by humans and
   * needs to be the same across development, production, etc. environments
   * (for example, the system maintenance message) should use \Drupal::config() instead.
   *
   * @return \Drupal\Core\State\StateInterface
   */
  public static function state() {
    return static::getContainer()
      ->get('state');
  }

  /**
   * Returns the default http client.
   *
   * @return \GuzzleHttp\Client
   *   A guzzle http client instance.
   */
  public static function httpClient() {
    return static::getContainer()
      ->get('http_client');
  }

  /**
   * Returns the entity query object for this entity type.
   *
   * @param string $entity_type
   *   The entity type (for example, node) for which the query object should be
   *   returned.
   * @param string $conjunction
   *   (optional) Either 'AND' if all conditions in the query need to apply, or
   *   'OR' if any of them is sufficient. Defaults to 'AND'.
   *
   * @return \Drupal\Core\Entity\Query\QueryInterface
   *   The query object that can query the given entity type.
   */
  public static function entityQuery($entity_type, $conjunction = 'AND') {
    return static::entityTypeManager()
      ->getStorage($entity_type)
      ->getQuery($conjunction);
  }

  /**
   * Returns the entity query aggregate object for this entity type.
   *
   * @param string $entity_type
   *   The entity type (for example, node) for which the query object should be
   *   returned.
   * @param string $conjunction
   *   (optional) Either 'AND' if all conditions in the query need to apply, or
   *   'OR' if any of them is sufficient. Defaults to 'AND'.
   *
   * @return \Drupal\Core\Entity\Query\QueryAggregateInterface
   *   The query object that can query the given entity type.
   */
  public static function entityQueryAggregate($entity_type, $conjunction = 'AND') {
    return static::entityTypeManager()
      ->getStorage($entity_type)
      ->getAggregateQuery($conjunction);
  }

  /**
   * Returns the flood instance.
   *
   * @return \Drupal\Core\Flood\FloodInterface
   */
  public static function flood() {
    return static::getContainer()
      ->get('flood');
  }

  /**
   * Returns the module handler.
   *
   * @return \Drupal\Core\Extension\ModuleHandlerInterface
   */
  public static function moduleHandler() {
    return static::getContainer()
      ->get('module_handler');
  }

  /**
   * Returns the typed data manager service.
   *
   * Use the typed data manager service for creating typed data objects.
   *
   * @return \Drupal\Core\TypedData\TypedDataManagerInterface
   *   The typed data manager.
   *
   * @see \Drupal\Core\TypedData\TypedDataManager::create()
   */
  public static function typedDataManager() {
    return static::getContainer()
      ->get('typed_data_manager');
  }

  /**
   * Returns the token service.
   *
   * @return \Drupal\Core\Utility\Token
   *   The token service.
   */
  public static function token() {
    return static::getContainer()
      ->get('token');
  }

  /**
   * Returns the url generator service.
   *
   * @return \Drupal\Core\Routing\UrlGeneratorInterface
   *   The url generator service.
   */
  public static function urlGenerator() {
    return static::getContainer()
      ->get('url_generator');
  }

  /**
   * Returns the link generator service.
   *
   * @return \Drupal\Core\Utility\LinkGeneratorInterface
   */
  public static function linkGenerator() {
    return static::getContainer()
      ->get('link_generator');
  }

  /**
   * Returns the string translation service.
   *
   * @return \Drupal\Core\StringTranslation\TranslationManager
   *   The string translation manager.
   */
  public static function translation() {
    return static::getContainer()
      ->get('string_translation');
  }

  /**
   * Returns the language manager service.
   *
   * @return \Drupal\Core\Language\LanguageManagerInterface
   *   The language manager.
   */
  public static function languageManager() {
    return static::getContainer()
      ->get('language_manager');
  }

  /**
   * Returns the CSRF token manager service.
   *
   * The generated token is based on the session ID of the current user. Normally,
   * anonymous users do not have a session, so the generated token will be
   * different on every page request. To generate a token for users without a
   * session, manually start a session prior to calling this function.
   *
   * @return \Drupal\Core\Access\CsrfTokenGenerator
   *   The CSRF token manager.
   *
   * @see \Drupal\Core\Session\SessionManager::start()
   */
  public static function csrfToken() {
    return static::getContainer()
      ->get('csrf_token');
  }

  /**
   * Returns the transliteration service.
   *
   * @return \Drupal\Core\Transliteration\PhpTransliteration
   *   The transliteration manager.
   */
  public static function transliteration() {
    return static::getContainer()
      ->get('transliteration');
  }

  /**
   * Returns the form builder service.
   *
   * @return \Drupal\Core\Form\FormBuilderInterface
   *   The form builder.
   */
  public static function formBuilder() {
    return static::getContainer()
      ->get('form_builder');
  }

  /**
   * Gets the theme service.
   *
   * @return \Drupal\Core\Theme\ThemeManagerInterface
   */
  public static function theme() {
    return static::getContainer()
      ->get('theme.manager');
  }

  /**
   * Gets the syncing state.
   *
   * @return bool
   *   Returns TRUE is syncing flag set.
   */
  public static function isConfigSyncing() {
    return static::getContainer()
      ->get('config.installer')
      ->isSyncing();
  }

  /**
   * Returns a channel logger object.
   *
   * @param string $channel
   *   The name of the channel. Can be any string, but the general practice is
   *   to use the name of the subsystem calling this.
   *
   * @return \Psr\Log\LoggerInterface
   *   The logger for this channel.
   */
  public static function logger($channel) {
    return static::getContainer()
      ->get('logger.factory')
      ->get($channel);
  }

  /**
   * Returns the menu tree.
   *
   * @return \Drupal\Core\Menu\MenuLinkTreeInterface
   *   The menu tree.
   */
  public static function menuTree() {
    return static::getContainer()
      ->get('menu.link_tree');
  }

  /**
   * Returns the path validator.
   *
   * @return \Drupal\Core\Path\PathValidatorInterface
   */
  public static function pathValidator() {
    return static::getContainer()
      ->get('path.validator');
  }

  /**
   * Returns the access manager service.
   *
   * @return \Drupal\Core\Access\AccessManagerInterface
   *   The access manager service.
   */
  public static function accessManager() {
    return static::getContainer()
      ->get('access_manager');
  }

  /**
   * Returns the redirect destination helper.
   *
   * @return \Drupal\Core\Routing\RedirectDestinationInterface
   *   The redirect destination helper.
   */
  public static function destination() {
    return static::getContainer()
      ->get('redirect.destination');
  }

  /**
   * Returns the entity definition update manager.
   *
   * @return \Drupal\Core\Entity\EntityDefinitionUpdateManagerInterface
   *   The entity definition update manager.
   */
  public static function entityDefinitionUpdateManager() {
    return static::getContainer()
      ->get('entity.definition_update_manager');
  }

  /**
   * Returns the time service.
   *
   * @return \Drupal\Component\Datetime\TimeInterface
   *   The time service.
   */
  public static function time() {
    return static::getContainer()
      ->get('datetime.time');
  }

  /**
   * Returns the messenger.
   *
   * @return \Drupal\Core\Messenger\MessengerInterface
   *   The messenger.
   */
  public static function messenger() {
    return static::getContainer()
      ->get('messenger');
  }

}

Members

Namesort descending Modifiers Type Description Overrides
Drupal::$container protected static property The currently active container object, or NULL if not initialized yet.
Drupal::accessManager public static function Returns the access manager service.
Drupal::cache public static function Returns the requested cache bin.
Drupal::classResolver public static function Retrieves the class resolver.
Drupal::config public static function Retrieves a configuration object.
Drupal::configFactory public static function Retrieves the configuration factory.
Drupal::CORE_COMPATIBILITY constant Core API compatibility.
Drupal::CORE_MINIMUM_SCHEMA_VERSION constant Core minimum schema version.
Drupal::csrfToken public static function Returns the CSRF token manager service.
Drupal::currentUser public static function Gets the current active user.
Drupal::database public static function Returns the current primary database.
Drupal::destination public static function Returns the redirect destination helper.
Drupal::entityDefinitionUpdateManager public static function Returns the entity definition update manager.
Drupal::entityQuery public static function Returns the entity query object for this entity type.
Drupal::entityQueryAggregate public static function Returns the entity query aggregate object for this entity type.
Drupal::entityTypeManager public static function Retrieves the entity type manager.
Drupal::flood public static function Returns the flood instance.
Drupal::formBuilder public static function Returns the form builder service.
Drupal::getContainer public static function Returns the currently active global container.
Drupal::hasContainer public static function Returns TRUE if the container has been initialized, FALSE otherwise.
Drupal::hasRequest public static function Indicates if there is a currently active request object.
Drupal::hasService public static function Indicates if a service is defined in the container.
Drupal::httpClient public static function Returns the default http client.
Drupal::installProfile public static function Gets the active install profile.
Drupal::isConfigSyncing public static function Gets the syncing state.
Drupal::keyValue public static function Returns a key/value storage collection.
Drupal::keyValueExpirable public static function Returns an expirable key value store collection.
Drupal::languageManager public static function Returns the language manager service.
Drupal::linkGenerator public static function Returns the link generator service.
Drupal::lock public static function Returns the locking layer instance.
Drupal::logger public static function Returns a channel logger object.
Drupal::menuTree public static function Returns the menu tree.
Drupal::messenger public static function Returns the messenger.
Drupal::MINIMUM_PHP constant Minimum allowed version of PHP for Drupal to be bootstrapped.
Drupal::MINIMUM_PHP_MEMORY_LIMIT constant Minimum recommended value of PHP memory_limit.
Drupal::MINIMUM_SUPPORTED_PHP constant Minimum supported version of PHP.
Drupal::moduleHandler public static function Returns the module handler.
Drupal::pathValidator public static function Returns the path validator.
Drupal::queue public static function Returns a queue for the given queue name.
Drupal::RECOMMENDED_PHP constant Minimum recommended version of PHP.
Drupal::request public static function Retrieves the currently active request object.
Drupal::requestStack public static function Retrieves the request stack.
Drupal::root public static function Gets the app root.
Drupal::routeMatch public static function Retrieves the currently active route match object.
Drupal::service public static function Retrieves a service from the container.
Drupal::setContainer public static function Sets a new global container.
Drupal::state public static function Returns the state storage service.
Drupal::theme public static function Gets the theme service.
Drupal::time public static function Returns the time service.
Drupal::token public static function Returns the token service.
Drupal::translation public static function Returns the string translation service.
Drupal::transliteration public static function Returns the transliteration service.
Drupal::typedDataManager public static function Returns the typed data manager service.
Drupal::unsetContainer public static function Unsets the global container.
Drupal::urlGenerator public static function Returns the url generator service.
Drupal::VERSION constant The current system version.