Issue #1814496 by Berdir, deviance, Lars Toomre: Make queue a container service.

core/includes/bootstrap.inc

@@ -958,7 +958,7 @@ function drupal_get_filename($type, $name, $filename = NULL) {
  *   The settings object.
  */
 function settings() {
-  return Settings::$singleton;
+  return Settings::getSingleton();
 }
 
 /**

core/includes/common.inc

@@ -6719,9 +6719,9 @@ function drupal_get_filetransfer_info() {
  * @param string $name
  *   The name of the queue to work with.
  * @param bool $reliable
- *   TRUE if the ordering of items and guaranteeing every item executes at
- *   least once is important, FALSE if scalability is the main concern. Defaults
- *   to FALSE.
+ *   (optional) TRUE if the ordering of items and guaranteeing every item
+ *   executes at least once is important, FALSE if scalability is the main
+ *   concern. Defaults to FALSE.
  *
  * @return Drupal\Core\Queue\QueueInterface
  *   The queue object for a given name.
@@ -6729,18 +6729,7 @@ function drupal_get_filetransfer_info() {
  * @see Drupal\Core\Queue\QueueInterface
  */
 function queue($name, $reliable = FALSE) {
-  static $queues;
-  if (!isset($queues[$name])) {
-    $class = variable_get('queue_class_' . $name, NULL);
-    if ($class && $reliable && in_array('Drupal\Core\Queue\ReliableQueueInterface', class_implements($class))) {
-      $class = variable_get('queue_default_reliable_class', 'Drupal\Core\Queue\System');
-    }
-    elseif (!$class) {
-      $class = variable_get('queue_default_class', 'Drupal\Core\Queue\System');
-    }
-    $queues[$name] = new $class($name);
-  }
-  return $queues[$name];
+  return drupal_container()->get('queue')->get($name, $reliable);
 }
 
 /**

core/includes/form.inc

@@ -6,8 +6,9 @@
  */
 
 use Drupal\Component\Utility\NestedArray;
-use Drupal\Core\Utility\Color;
+use Drupal\Core\Database\Database;
 use Drupal\Core\Template\Attribute;
+use Drupal\Core\Utility\Color;
 
 /**
  * @defgroup forms Form builder functions
@@ -5204,7 +5205,7 @@ function _batch_queue($batch_set) {
     $class = $batch_set['queue']['class'];
 
     if (!isset($queues[$class][$name])) {
-      $queues[$class][$name] = new $class($name);
+      $queues[$class][$name] = new $class($name, Database::getConnection());
     }
     return $queues[$class][$name];
   }

core/lib/Drupal/Component/Utility/Settings.php

@@ -2,29 +2,51 @@
 
 /**
  * @file
- * Contains Drupal\Component\Utility\Settings.
+ * Contains \Drupal\Component\Utility\Settings.
  */
 
 namespace Drupal\Component\Utility;
 
-class Settings {
+/**
+ * Read only settings that are initialized with the class.
+ */
+final class Settings {
 
   /**
+   * Array with the settings.
+   *
    * @var array
    */
-  protected $storage;
+  private $storage = array();
 
   /**
-   * @var Settings
+   * Singleton instance.
+   *
+   * @var \Drupal\Component\Utility\Settings
    */
-  static $singleton;
+  private static $instance;
 
   /**
+   * Returns the settings instance.
+   *
+   * A singleton is used because this class is used before the container is
+   * available.
+   *
+   * @return \Drupal\Component\Utility\Settings
+   */
+  public static function getSingleton() {
+    return self::$instance;
+  }
+
+  /**
+   * Constructor.
+   *
    * @param array $settings
+   *   Array with the settings.
    */
   function __construct(array $settings) {
     $this->storage = $settings;
-    self::$singleton = $this;
+    self::$instance = $this;
   }
 
   /**

core/lib/Drupal/Core/CoreBundle.php

@@ -73,6 +73,19 @@ public function build(ContainerBuilder $container) {
       ->register('keyvalue.database', 'Drupal\Core\KeyValueStore\KeyValueDatabaseFactory')
       ->addArgument(new Reference('database'));
 
+    $container->register('settings', 'Drupal\Component\Utility\Settings')
+      ->setFactoryClass('Drupal\Component\Utility\Settings')
+      ->setFactoryMethod('getSingleton');
+
+    // Register the Queue factory.
+    $container
+      ->register('queue', 'Drupal\Core\Queue\QueueFactory')
+      ->addArgument(new Reference('settings'))
+      ->addMethodCall('setContainer', array(new Reference('service_container')));
+    $container
+      ->register('queue.database', 'Drupal\Core\Queue\QueueDatabaseFactory')
+      ->addArgument(new Reference('database'));
+
     $container->register('path.alias_manager', 'Drupal\Core\Path\AliasManager')
       ->addArgument(new Reference('database'))
       ->addArgument(new Reference('keyvalue'));

core/lib/Drupal/Core/Queue/Batch.php

@@ -18,7 +18,7 @@
  * Stale items from failed batches are cleaned from the {queue} table on cron
  * using the 'created' date.
  */
-class Batch extends System {
+class Batch extends DatabaseQueue {
 
   /**
    * Overrides Drupal\Core\Queue\System::claimItem().

core/lib/Drupal/Core/Queue/System.php → core/lib/Drupal/Core/Queue/DatabaseQueue.php

@@ -2,15 +2,18 @@
 
 /**
  * @file
- * Definition of Drupal\Core\Queue\System.
+ * Contains \Drupal\Core\Queue\DatabaseQueue.
  */
 
 namespace Drupal\Core\Queue;
 
+use Drupal\Core\Database\Connection;
+
 /**
  * Default queue implementation.
  */
-class System implements ReliableQueueInterface {
+class DatabaseQueue implements ReliableQueueInterface {
+
   /**
    * The name of the queue this instance is working with.
    *
@@ -19,22 +22,30 @@ class System implements ReliableQueueInterface {
   protected $name;
 
   /**
-   * Constructs a System object.
+   * The database connection.
+   *
+   * @var \Drupal\Core\Database\Connection $connection
+   */
+  protected $connection;
+
+  /**
+   * Constructs this factory object.
    *
    * @param string $name
-   *   An arbitrary string. The name of the queue to work with.
+   *   The name of the queue.
+   * @param \Drupal\Core\Database\Connection $connection
+   *   The Connection object containing the key-value tables.
    */
-  public function __construct($name) {
+  function __construct($name, Connection $connection) {
     $this->name = $name;
+    $this->connection = $connection;
   }
 
   /**
    * Implements Drupal\Core\Queue\QueueInterface::createItem().
    */
   public function createItem($data) {
-    // During a Drupal 6.x to 8.x update, drupal_get_schema() does not contain
-    // the queue table yet, so we cannot rely on drupal_write_record().
-    $query = db_insert('queue')
+    $query = $this->connection->insert('queue')
       ->fields(array(
         'name' => $this->name,
         'data' => serialize($data),
@@ -49,7 +60,7 @@ public function createItem($data) {
    * Implements Drupal\Core\Queue\QueueInterface::numberOfItems().
    */
   public function numberOfItems() {
-    return db_query('SELECT COUNT(item_id) FROM {queue} WHERE name = :name', array(':name' => $this->name))->fetchField();
+    return $this->connection->query('SELECT COUNT(item_id) FROM {queue} WHERE name = :name', array(':name' => $this->name))->fetchField();
   }
 
   /**
@@ -61,7 +72,7 @@ public function claimItem($lease_time = 30) {
     // until an item is successfully claimed or we are reasonably sure there
     // are no unclaimed items left.
     while (TRUE) {
-      $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE expire = 0 AND name = :name ORDER BY created ASC', 0, 1, array(':name' => $this->name))->fetchObject();
+      $item = $this->connection->queryRange('SELECT data, item_id FROM {queue} q WHERE expire = 0 AND name = :name ORDER BY created ASC', 0, 1, array(':name' => $this->name))->fetchObject();
       if ($item) {
         // Try to update the item. Only one thread can succeed in UPDATEing the
         // same row. We cannot rely on REQUEST_TIME because items might be
@@ -69,7 +80,7 @@ public function claimItem($lease_time = 30) {
         // continue to use REQUEST_TIME instead of the current time(), we steal
         // time from the lease, and will tend to reset items before the lease
         // should really expire.
-        $update = db_update('queue')
+        $update = $this->connection->update('queue')
           ->fields(array(
             'expire' => time() + $lease_time,
           ))
@@ -92,7 +103,7 @@ public function claimItem($lease_time = 30) {
    * Implements Drupal\Core\Queue\QueueInterface::releaseItem().
    */
   public function releaseItem($item) {
-    $update = db_update('queue')
+    $update = $this->connection->update('queue')
       ->fields(array(
         'expire' => 0,
       ))
@@ -104,7 +115,7 @@ public function releaseItem($item) {
    * Implements Drupal\Core\Queue\QueueInterface::deleteItem().
    */
   public function deleteItem($item) {
-    db_delete('queue')
+    $this->connection->delete('queue')
       ->condition('item_id', $item->item_id)
       ->execute();
   }
@@ -122,7 +133,7 @@ public function createQueue() {
    * Implements Drupal\Core\Queue\QueueInterface::deleteQueue().
    */
   public function deleteQueue() {
-    db_delete('queue')
+    $this->connection->delete('queue')
       ->condition('name', $this->name)
       ->execute();
   }

core/lib/Drupal/Core/Queue/QueueDatabaseFactory.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Queue\QueueDatabaseFactory.
+ */
+
+namespace Drupal\Core\Queue;
+
+use Drupal\Core\Database\Connection;
+
+/**
+ * Defines the key/value store factory for the database backend.
+ */
+class QueueDatabaseFactory {
+
+  /**
+   * The database connection.
+   *
+   * @var \Drupal\Core\Database\Connection $connection
+   */
+  protected $connection;
+
+  /**
+   * Constructs this factory object.
+   *
+   * @param \Drupal\Core\Database\Connection $connection
+   *   The Connection object containing the key-value tables.
+   */
+  function __construct(Connection $connection) {
+    $this->connection = $connection;
+  }
+
+  /**
+   * Constructs a new queue object for a given name.
+   *
+   * @param string $name
+   *   The name of the collection holding key and value pairs.
+   * @param \Drupal\Core\Database\Connection $connection
+   *   The connection to run against.
+   *
+   * @return \Drupal\Core\QueueStore\DatabaseStorage
+   *   A key/value store implementation for the given $collection.
+   */
+  public function get($name) {
+    return new DatabaseQueue($name, $this->connection);
+  }
+}

core/lib/Drupal/Core/Queue/QueueFactory.php

+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Queue\QueueFactory.
+ */
+
+namespace Drupal\Core\Queue;
+
+use Drupal\Component\Utility\Settings;
+use Symfony\Component\DependencyInjection\ContainerAware;
+
+/**
+ * Defines the queue factory.
+ */
+class QueueFactory extends ContainerAware {
+
+  /**
+   * Instantiated queues, keyed by name.
+   *
+   * @var array
+   */
+  protected $queues = array();
+
+  /**
+   * The settings object.
+   *
+   * @var \Drupal\Component\Utility\Settings
+   */
+  protected $settings;
+
+
+  /**
+   * Constructs a queue factory.
+   */
+  function __construct(Settings $settings) {
+    $this->settings = $settings;
+  }
+
+  /**
+   * Constructs a new queue.
+   *
+   * @param string $name
+   *   The name of the queue to work with.
+   * @param bool $reliable
+   *   (optional) TRUE if the ordering of items and guaranteeing every item executes at
+   *   least once is important, FALSE if scalability is the main concern. Defaults
+   *   to FALSE.
+   *
+   * @return \Drupal\Core\QueueStore\QueueInterface
+   *   A queue implementation for the given name.
+   */
+  public function get($name, $reliable = FALSE) {
+    if (!isset($this->queues[$name])) {
+      // If it is a reliable queue, check the specific settings first.
+      if ($reliable) {
+        $service_name = $this->settings->get('queue_reliable_service_' . $name);
+      }
+      // If no reliable queue was defined, check the service and global
+      // settings, fall back to queue.database.
+      if (empty($service_name)) {
+        $service_name = $this->settings->get('queue_service_' . $name, $this->settings->get('queue_default', 'queue.database'));
+      }
+      $this->queues[$name] = $this->container->get($service_name)->get($name);
+    }
+    return $this->queues[$name];
+  }
+}
+

core/modules/system/lib/Drupal/system/Tests/Queue/QueueTest.php

@@ -7,14 +7,23 @@
 
 namespace Drupal\system\Tests\Queue;
 
+use Drupal\Core\Database\Database;
+use Drupal\Core\Queue\DatabaseQueue;
 use Drupal\Core\Queue\Memory;
-use Drupal\Core\Queue\System;
-use Drupal\simpletest\WebTestBase;
+use Drupal\simpletest\DrupalUnitTestBase;
 
 /**
  * Tests the basic queue functionality.
  */
-class QueueTest extends WebTestBase {
+class QueueTest extends DrupalUnitTestBase {
+
+  /**
+   * The modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('system');
+
   public static function getInfo() {
     return array(
       'name' => 'Queue functionality',
@@ -27,10 +36,11 @@ public static function getInfo() {
    * Tests the System queue.
    */
   public function testSystemQueue() {
+    $this->installSchema('system', 'queue');
     // Create two queues.
-    $queue1 = new System($this->randomName());
+    $queue1 = new DatabaseQueue($this->randomName(), Database::getConnection());
     $queue1->createQueue();
-    $queue2 = new System($this->randomName());
+    $queue2 = new DatabaseQueue($this->randomName(), Database::getConnection());
     $queue2->createQueue();
 
     $this->queueTest($queue1, $queue2);