class DatabaseFileUsageBackend in Zircon Profile 8

Defines the database file usage backend. This is the default Drupal backend.

Hierarchy

• class \Drupal\file\FileUsage\FileUsageBase implements FileUsageInterface
  • class \Drupal\file\FileUsage\DatabaseFileUsageBackend

1 string reference to 'DatabaseFileUsageBackend'

file.services.yml in core/modules/file/file.services.yml

core/modules/file/file.services.yml

1 service uses DatabaseFileUsageBackend

file.usage in core/modules/file/file.services.yml

Drupal\file\FileUsage\DatabaseFileUsageBackend

File

core/modules/file/src/FileUsage/DatabaseFileUsageBackend.php, line 16

Contains \Drupal\file\FileUsage\DatabaseFileUsageBackend.

Namespace

Drupal\file\FileUsage

class DatabaseFileUsageBackend extends FileUsageBase {

  /**
   * The database connection used to store file usage information.
   *
   * @var \Drupal\Core\Database\Connection
   */
  protected $connection;

  /**
   * The name of the SQL table used to store file usage information.
   *
   * @var string
   */
  protected $tableName;

  /**
   * Construct the DatabaseFileUsageBackend.
   *
   * @param \Drupal\Core\Database\Connection $connection
   *   The database connection which will be used to store the file usage
   *   information.
   * @param string $table
   *   (optional) The table to store file usage info. Defaults to 'file_usage'.
   */
  public function __construct(Connection $connection, $table = 'file_usage') {
    $this->connection = $connection;
    $this->tableName = $table;
  }

  /**
   * {@inheritdoc}
   */
  public function add(FileInterface $file, $module, $type, $id, $count = 1) {
    $this->connection
      ->merge($this->tableName)
      ->keys(array(
      'fid' => $file
        ->id(),
      'module' => $module,
      'type' => $type,
      'id' => $id,
    ))
      ->fields(array(
      'count' => $count,
    ))
      ->expression('count', 'count + :count', array(
      ':count' => $count,
    ))
      ->execute();
    parent::add($file, $module, $type, $id, $count);
  }

  /**
   * {@inheritdoc}
   */
  public function delete(FileInterface $file, $module, $type = NULL, $id = NULL, $count = 1) {

    // Delete rows that have a exact or less value to prevent empty rows.
    $query = $this->connection
      ->delete($this->tableName)
      ->condition('module', $module)
      ->condition('fid', $file
      ->id());
    if ($type && $id) {
      $query
        ->condition('type', $type)
        ->condition('id', $id);
    }
    if ($count) {
      $query
        ->condition('count', $count, '<=');
    }
    $result = $query
      ->execute();

    // If the row has more than the specified count decrement it by that number.
    if (!$result && $count > 0) {
      $query = $this->connection
        ->update($this->tableName)
        ->condition('module', $module)
        ->condition('fid', $file
        ->id());
      if ($type && $id) {
        $query
          ->condition('type', $type)
          ->condition('id', $id);
      }
      $query
        ->expression('count', 'count - :count', array(
        ':count' => $count,
      ));
      $query
        ->execute();
    }
    parent::delete($file, $module, $type, $id, $count);
  }

  /**
   * {@inheritdoc}
   */
  public function listUsage(FileInterface $file) {
    $result = $this->connection
      ->select($this->tableName, 'f')
      ->fields('f', array(
      'module',
      'type',
      'id',
      'count',
    ))
      ->condition('fid', $file
      ->id())
      ->condition('count', 0, '>')
      ->execute();
    $references = array();
    foreach ($result as $usage) {
      $references[$usage->module][$usage->type][$usage->id] = $usage->count;
    }
    return $references;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DatabaseFileUsageBackend::$connection	protected	property	The database connection used to store file usage information.
DatabaseFileUsageBackend::$tableName	protected	property	The name of the SQL table used to store file usage information.
DatabaseFileUsageBackend::add	public	function	Records that a module is using a file. Overrides FileUsageBase::add
DatabaseFileUsageBackend::delete	public	function	Removes a record to indicate that a module is no longer using a file. Overrides FileUsageBase::delete
DatabaseFileUsageBackend::listUsage	public	function	Determines where a file is used. Overrides FileUsageInterface::listUsage
DatabaseFileUsageBackend::__construct	public	function	Construct the DatabaseFileUsageBackend.