MongoDBCache.php in Plug 7

Namespace

Doctrine\Common\Cache

File

lib/doctrine/cache/lib/Doctrine/Common/Cache/MongoDBCache.php

<?php

/*
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the MIT license. For more information, see
 * <http://www.doctrine-project.org>.
 */
namespace Doctrine\Common\Cache;

use MongoBinData;
use MongoCollection;
use MongoDate;

/**
 * MongoDB cache provider.
 *
 * @since  1.1
 * @author Jeremy Mikola <[e-mail]>
 */
class MongoDBCache extends CacheProvider {

  /**
   * The data field will store the serialized PHP value.
   */
  const DATA_FIELD = 'd';

  /**
   * The expiration field will store a MongoDate value indicating when the
   * cache entry should expire.
   *
   * With MongoDB 2.2+, entries can be automatically deleted by MongoDB by
   * indexing this field wit the "expireAfterSeconds" option equal to zero.
   * This will direct MongoDB to regularly query for and delete any entries
   * whose date is older than the current time. Entries without a date value
   * in this field will be ignored.
   *
   * The cache provider will also check dates on its own, in case expired
   * entries are fetched before MongoDB's TTLMonitor pass can expire them.
   *
   * @see http://docs.mongodb.org/manual/tutorial/expire-data/
   */
  const EXPIRATION_FIELD = 'e';

  /**
   * @var MongoCollection
   */
  private $collection;

  /**
   * Constructor.
   *
   * This provider will default to the write concern and read preference
   * options set on the MongoCollection instance (or inherited from MongoDB or
   * MongoClient). Using an unacknowledged write concern (< 1) may make the
   * return values of delete() and save() unreliable. Reading from secondaries
   * may make contain() and fetch() unreliable.
   *
   * @see http://www.php.net/manual/en/mongo.readpreferences.php
   * @see http://www.php.net/manual/en/mongo.writeconcerns.php
   * @param MongoCollection $collection
   */
  public function __construct(MongoCollection $collection) {
    $this->collection = $collection;
  }

  /**
   * {@inheritdoc}
   */
  protected function doFetch($id) {
    $document = $this->collection
      ->findOne(array(
      '_id' => $id,
    ), array(
      self::DATA_FIELD,
      self::EXPIRATION_FIELD,
    ));
    if ($document === null) {
      return false;
    }
    if ($this
      ->isExpired($document)) {
      $this
        ->doDelete($id);
      return false;
    }
    return unserialize($document[self::DATA_FIELD]->bin);
  }

  /**
   * {@inheritdoc}
   */
  protected function doContains($id) {
    $document = $this->collection
      ->findOne(array(
      '_id' => $id,
    ), array(
      self::EXPIRATION_FIELD,
    ));
    if ($document === null) {
      return false;
    }
    if ($this
      ->isExpired($document)) {
      $this
        ->doDelete($id);
      return false;
    }
    return true;
  }

  /**
   * {@inheritdoc}
   */
  protected function doSave($id, $data, $lifeTime = 0) {
    $result = $this->collection
      ->update(array(
      '_id' => $id,
    ), array(
      '$set' => array(
        self::EXPIRATION_FIELD => $lifeTime > 0 ? new MongoDate(time() + $lifeTime) : null,
        self::DATA_FIELD => new MongoBinData(serialize($data), MongoBinData::BYTE_ARRAY),
      ),
    ), array(
      'upsert' => true,
      'multiple' => false,
    ));
    return isset($result['ok']) ? $result['ok'] == 1 : true;
  }

  /**
   * {@inheritdoc}
   */
  protected function doDelete($id) {
    $result = $this->collection
      ->remove(array(
      '_id' => $id,
    ));
    return isset($result['n']) ? $result['n'] == 1 : true;
  }

  /**
   * {@inheritdoc}
   */
  protected function doFlush() {

    // Use remove() in lieu of drop() to maintain any collection indexes
    $result = $this->collection
      ->remove();
    return isset($result['ok']) ? $result['ok'] == 1 : true;
  }

  /**
   * {@inheritdoc}
   */
  protected function doGetStats() {
    $serverStatus = $this->collection->db
      ->command(array(
      'serverStatus' => 1,
      'locks' => 0,
      'metrics' => 0,
      'recordStats' => 0,
      'repl' => 0,
    ));
    $collStats = $this->collection->db
      ->command(array(
      'collStats' => 1,
    ));
    return array(
      Cache::STATS_HITS => null,
      Cache::STATS_MISSES => null,
      Cache::STATS_UPTIME => isset($serverStatus['uptime']) ? (int) $serverStatus['uptime'] : null,
      Cache::STATS_MEMORY_USAGE => isset($collStats['size']) ? (int) $collStats['size'] : null,
      Cache::STATS_MEMORY_AVAILABLE => null,
    );
  }

  /**
   * Check if the document is expired.
   *
   * @param array $document
   * @return boolean
   */
  private function isExpired(array $document) {
    return isset($document[self::EXPIRATION_FIELD]) && $document[self::EXPIRATION_FIELD] instanceof MongoDate && $document[self::EXPIRATION_FIELD]->sec < time();
  }

}

Classes

Name	Description
MongoDBCache	MongoDB cache provider.