class TempStore

TempStoreDatabaseTest::getInfo in drupal/core/modules/user/lib/Drupal/user/Tests/TempStoreDatabaseTest.php

class TempStore {

  /**
   * The key/value storage object used for this data.
   *
   * @var Drupal\Core\KeyValueStore\KeyValueStoreExpireInterface;
   */
  protected $storage;

  /**
   * The lock object used for this data.
   *
   * @var Drupal\Core\Lock\LockBackendInterface
   */
  protected $lockBackend;

  /**
   * The owner key to store along with the data (e.g. a user or session ID).
   *
   * @var mixed
   */
  protected $owner;

  /**
   * The time to live for items in seconds.
   *
   * By default, data is stored for one week (604800 seconds) before expiring.
   *
   * @var int
   *
   * @todo Currently, this property is not exposed anywhere, and so the only
   *   way to override it is by extending the class.
   */
  protected $expire = 604800;

  /**
   * Constructs a new object for accessing data from a key/value store.
   *
   * @param KeyValueStoreExpireInterface $storage
   *   The key/value storage object used for this data. Each storage object
   *   represents a particular collection of data and will contain any number
   *   of key/value pairs.
   * @param Drupal\Core\Lock\LockBackendInterface $lockBackend
   *   The lock object used for this data.
   * @param mixed $owner
   *   The owner key to store along with the data (e.g. a user or session ID).
   */
  function __construct(KeyValueStoreExpirableInterface $storage, LockBackendInterface $lockBackend, $owner) {
    $this->storage = $storage;
    $this->lockBackend = $lockBackend;
    $this->owner = $owner;
  }

  /**
   * Retrieves a value from this TempStore for a given key.
   *
   * @param string $key
   *   The key of the data to retrieve.
   *
   * @return mixed
   *   The data associated with the key, or NULL if the key does not exist.
   */
  function get($key) {
    if ($object = $this->storage
      ->get($key)) {
      return $object->data;
    }
  }

  /**
   * Stores a particular key/value pair only if the key doesn't already exist.
   *
   * @param string $key
   *   The key of the data to check and store.
   * @param mixed $value
   *   The data to store.
   *
   * @return bool
   *   TRUE if the data was set, or FALSE if it already existed.
   */
  function setIfNotExists($key, $value) {
    $value = (object) array(
      'owner' => $this->owner,
      'data' => $value,
      'updated' => REQUEST_TIME,
    );
    return $this->storage
      ->setWithExpireIfNotExists($key, $value, $this->expire);
  }

  /**
   * Stores a particular key/value pair in this TempStore.
   *
   * @param string $key
   *   The key of the data to store.
   * @param mixed $value
   *   The data to store.
   */
  function set($key, $value) {
    if (!$this->lockBackend
      ->acquire($key)) {
      $this->lockBackend
        ->wait($key);
      if (!$this->lockBackend
        ->acquire($key)) {
        throw new TempStoreException(format_string("Couldn't acquire lock to update item %key in %collection temporary storage.", array(
          '%key' => $key,
          '%collection' => $this->storage->collection,
        )));
      }
    }
    $value = (object) array(
      'owner' => $this->owner,
      'data' => $value,
      'updated' => REQUEST_TIME,
    );
    $this->storage
      ->setWithExpire($key, $value, $this->expire);
    $this->lockBackend
      ->release($key);
  }

  /**
   * Returns the metadata associated with a particular key/value pair.
   *
   * @param string $key
   *   The key of the data to store.
   *
   * @return mixed
   *   An object with the owner and updated time if the key has a value, or
   *   NULL otherwise.
   */
  function getMetadata($key) {

    // Fetch the key/value pair and its metadata.
    $object = $this->storage
      ->get($key);
    if ($object) {

      // Don't keep the data itself in memory.
      unset($object->data);
      return $object;
    }
  }

  /**
   * Deletes data from the store for a given key and releases the lock on it.
   *
   * @param string $key
   *   The key of the data to delete.
   */
  function delete($key) {
    if (!$this->lockBackend
      ->acquire($key)) {
      $this->lockBackend
        ->wait($key);
      if (!$this->lockBackend
        ->acquire($key)) {
        throw new TempStoreException(format_string("Couldn't acquire lock to delete item %key from %collection temporary storage.", array(
          '%key' => $key,
          '%collection' => $this->storage->collection,
        )));
      }
    }
    $this->storage
      ->delete($key);
    $this->lockBackend
      ->release($key);
  }

}