class DatabaseStorage in Drupal 8

Defines a default key/value store implementation.

This is Drupal's default key/value store implementation. It uses the database to store key/value data.

Hierarchy

• class \Drupal\Core\KeyValueStore\StorageBase implements KeyValueStoreInterface
  • class \Drupal\Core\KeyValueStore\DatabaseStorage uses DependencySerializationTrait

File

core/lib/Drupal/Core/KeyValueStore/DatabaseStorage.php, line 16

Namespace

Drupal\Core\KeyValueStore

class DatabaseStorage extends StorageBase {
  use DependencySerializationTrait;

  /**
   * The serialization class to use.
   *
   * @var \Drupal\Component\Serialization\SerializationInterface
   */
  protected $serializer;

  /**
   * The database connection.
   *
   * @var \Drupal\Core\Database\Connection
   */
  protected $connection;

  /**
   * The name of the SQL table to use.
   *
   * @var string
   */
  protected $table;

  /**
   * Overrides Drupal\Core\KeyValueStore\StorageBase::__construct().
   *
   * @param string $collection
   *   The name of the collection holding key and value pairs.
   * @param \Drupal\Component\Serialization\SerializationInterface $serializer
   *   The serialization class to use.
   * @param \Drupal\Core\Database\Connection $connection
   *   The database connection to use.
   * @param string $table
   *   The name of the SQL table to use, defaults to key_value.
   */
  public function __construct($collection, SerializationInterface $serializer, Connection $connection, $table = 'key_value') {
    parent::__construct($collection);
    $this->serializer = $serializer;
    $this->connection = $connection;
    $this->table = $table;
  }

  /**
   * {@inheritdoc}
   */
  public function has($key) {
    return (bool) $this->connection
      ->query('SELECT 1 FROM {' . $this->connection
      ->escapeTable($this->table) . '} WHERE collection = :collection AND name = :key', [
      ':collection' => $this->collection,
      ':key' => $key,
    ])
      ->fetchField();
  }

  /**
   * {@inheritdoc}
   */
  public function getMultiple(array $keys) {
    $values = [];
    try {
      $result = $this->connection
        ->query('SELECT name, value FROM {' . $this->connection
        ->escapeTable($this->table) . '} WHERE name IN ( :keys[] ) AND collection = :collection', [
        ':keys[]' => $keys,
        ':collection' => $this->collection,
      ])
        ->fetchAllAssoc('name');
      foreach ($keys as $key) {
        if (isset($result[$key])) {
          $values[$key] = $this->serializer
            ->decode($result[$key]->value);
        }
      }
    } catch (\Exception $e) {

      // @todo: Perhaps if the database is never going to be available,
      // key/value requests should return FALSE in order to allow exception
      // handling to occur but for now, keep it an array, always.
    }
    return $values;
  }

  /**
   * {@inheritdoc}
   */
  public function getAll() {
    $result = $this->connection
      ->query('SELECT name, value FROM {' . $this->connection
      ->escapeTable($this->table) . '} WHERE collection = :collection', [
      ':collection' => $this->collection,
    ]);
    $values = [];
    foreach ($result as $item) {
      if ($item) {
        $values[$item->name] = $this->serializer
          ->decode($item->value);
      }
    }
    return $values;
  }

  /**
   * {@inheritdoc}
   */
  public function set($key, $value) {
    $this->connection
      ->merge($this->table)
      ->keys([
      'name' => $key,
      'collection' => $this->collection,
    ])
      ->fields([
      'value' => $this->serializer
        ->encode($value),
    ])
      ->execute();
  }

  /**
   * {@inheritdoc}
   */
  public function setIfNotExists($key, $value) {
    $result = $this->connection
      ->merge($this->table)
      ->insertFields([
      'collection' => $this->collection,
      'name' => $key,
      'value' => $this->serializer
        ->encode($value),
    ])
      ->condition('collection', $this->collection)
      ->condition('name', $key)
      ->execute();
    return $result == Merge::STATUS_INSERT;
  }

  /**
   * {@inheritdoc}
   */
  public function rename($key, $new_key) {
    $this->connection
      ->update($this->table)
      ->fields([
      'name' => $new_key,
    ])
      ->condition('collection', $this->collection)
      ->condition('name', $key)
      ->execute();
  }

  /**
   * {@inheritdoc}
   */
  public function deleteMultiple(array $keys) {

    // Delete in chunks when a large array is passed.
    while ($keys) {
      $this->connection
        ->delete($this->table)
        ->condition('name', array_splice($keys, 0, 1000), 'IN')
        ->condition('collection', $this->collection)
        ->execute();
    }
  }

  /**
   * {@inheritdoc}
   */
  public function deleteAll() {
    $this->connection
      ->delete($this->table)
      ->condition('collection', $this->collection)
      ->execute();
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DatabaseStorage::$connection	protected	property	The database connection.
DatabaseStorage::$serializer	protected	property	The serialization class to use.
DatabaseStorage::$table	protected	property	The name of the SQL table to use.
DatabaseStorage::deleteAll	public	function	Deletes all items from the key/value store. Overrides KeyValueStoreInterface::deleteAll
DatabaseStorage::deleteMultiple	public	function	Deletes multiple items from the key/value store. Overrides KeyValueStoreInterface::deleteMultiple	1
DatabaseStorage::getAll	public	function	Returns all stored key/value pairs in the collection. Overrides KeyValueStoreInterface::getAll	1
DatabaseStorage::getMultiple	public	function	Returns the stored key/value pairs for a given set of keys. Overrides KeyValueStoreInterface::getMultiple	1
DatabaseStorage::has	public	function	Returns whether a given key exists in the store. Overrides KeyValueStoreInterface::has	1
DatabaseStorage::rename	public	function	Renames a key. Overrides KeyValueStoreInterface::rename
DatabaseStorage::set	public	function	Saves a value for a given key. Overrides KeyValueStoreInterface::set
DatabaseStorage::setIfNotExists	public	function	Saves a value for a given key if it does not exist yet. Overrides KeyValueStoreInterface::setIfNotExists
DatabaseStorage::__construct	public	function	Overrides Drupal\Core\KeyValueStore\StorageBase::__construct(). Overrides StorageBase::__construct	1
DependencySerializationTrait::$_entityStorages	protected	property	An array of entity type IDs keyed by the property name of their storages.
DependencySerializationTrait::$_serviceIds	protected	property	An array of service IDs keyed by property name used for serialization.
DependencySerializationTrait::__sleep	public	function		1
DependencySerializationTrait::__wakeup	public	function		2
StorageBase::$collection	protected	property	The name of the collection holding key and value pairs.
StorageBase::delete	public	function	Deletes an item from the key/value store. Overrides KeyValueStoreInterface::delete	1
StorageBase::get	public	function	Returns the stored value for a given key. Overrides KeyValueStoreInterface::get	1
StorageBase::getCollectionName	public	function	Returns the name of this collection. Overrides KeyValueStoreInterface::getCollectionName
StorageBase::setMultiple	public	function	Saves key/value pairs. Overrides KeyValueStoreInterface::setMultiple	1