SQLite3Cache.php in Plug 7

Namespace

Doctrine\Common\Cache

File

lib/doctrine/cache/lib/Doctrine/Common/Cache/SQLite3Cache.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 SQLite3;
use SQLite3Result;

/**
 * SQLite3 cache provider.
 *
 * @since  1.4
 * @author Jake Bell <[e-mail]>
 */
class SQLite3Cache extends CacheProvider {

  /**
   * The ID field will store the cache key.
   */
  const ID_FIELD = 'k';

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

  /**
   * The expiration field will store a date value indicating when the
   * cache entry should expire.
   */
  const EXPIRATION_FIELD = 'e';

  /**
   * @var SQLite3
   */
  private $sqlite;

  /**
   * @var string
   */
  private $table;

  /**
   * Constructor.
   *
   * Calling the constructor will ensure that the database file and table
   * exist and will create both if they don't.
   *
   * @param SQLite3 $sqlite
   * @param string $table
   */
  public function __construct(SQLite3 $sqlite, $table) {
    $this->sqlite = $sqlite;
    $this->table = (string) $table;
    list($id, $data, $exp) = $this
      ->getFields();
    return $this->sqlite
      ->exec(sprintf('CREATE TABLE IF NOT EXISTS %s(%s TEXT PRIMARY KEY NOT NULL, %s BLOB, %s INTEGER)', $table, $id, $data, $exp));
  }

  /**
   * {@inheritdoc}
   */
  protected function doFetch($id) {
    if ($item = $this
      ->findById($id)) {
      return unserialize($item[self::DATA_FIELD]);
    }
    return false;
  }

  /**
   * {@inheritdoc}
   */
  protected function doContains($id) {
    return (bool) $this
      ->findById($id, false);
  }

  /**
   * {@inheritdoc}
   */
  protected function doSave($id, $data, $lifeTime = 0) {
    $statement = $this->sqlite
      ->prepare(sprintf('INSERT OR REPLACE INTO %s (%s) VALUES (:id, :data, :expire)', $this->table, implode(',', $this
      ->getFields())));
    $statement
      ->bindValue(':id', $id);
    $statement
      ->bindValue(':data', serialize($data), SQLITE3_BLOB);
    $statement
      ->bindValue(':expire', $lifeTime > 0 ? time() + $lifeTime : null);
    return $statement
      ->execute() instanceof SQLite3Result;
  }

  /**
   * {@inheritdoc}
   */
  protected function doDelete($id) {
    list($idField) = $this
      ->getFields();
    $statement = $this->sqlite
      ->prepare(sprintf('DELETE FROM %s WHERE %s = :id', $this->table, $idField));
    $statement
      ->bindValue(':id', $id);
    return $statement
      ->execute() instanceof SQLite3Result;
  }

  /**
   * {@inheritdoc}
   */
  protected function doFlush() {
    return $this->sqlite
      ->exec(sprintf('DELETE FROM %s', $this->table));
  }

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

    // no-op.
  }

  /**
   * Find a single row by ID.
   *
   * @param mixed $id
   * @param boolean $includeData
   *
   * @return array|null
   */
  private function findById($id, $includeData = true) {
    list($idField) = $fields = $this
      ->getFields();
    if (!$includeData) {
      $key = array_search(static::DATA_FIELD, $fields);
      unset($fields[$key]);
    }
    $statement = $this->sqlite
      ->prepare(sprintf('SELECT %s FROM %s WHERE %s = :id LIMIT 1', implode(',', $fields), $this->table, $idField));
    $statement
      ->bindValue(':id', $id, SQLITE3_TEXT);
    $item = $statement
      ->execute()
      ->fetchArray(SQLITE3_ASSOC);
    if ($item === false) {
      return null;
    }
    if ($this
      ->isExpired($item)) {
      $this
        ->doDelete($id);
      return null;
    }
    return $item;
  }

  /**
   * Gets an array of the fields in our table.
   *
   * @return array
   */
  private function getFields() {
    return array(
      static::ID_FIELD,
      static::DATA_FIELD,
      static::EXPIRATION_FIELD,
    );
  }

  /**
   * Check if the item is expired.
   *
   * @param array $item
   * @return boolean
   */
  private function isExpired(array $item) {
    return isset($item[static::EXPIRATION_FIELD]) && $item[self::EXPIRATION_FIELD] !== null && $item[self::EXPIRATION_FIELD] < time();
  }

}

Classes

Name	Description
SQLite3Cache	SQLite3 cache provider.