StoreInterface.php

<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * This code is partially based on the Rack-Cache library by Ryan Tomayko,
 * which is released under the MIT license.
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace Symfony\Component\HttpKernel\HttpCache;

use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

/**
 * Interface implemented by HTTP cache stores.
 *
 * @author Fabien Potencier <fabien@symfony.com>
 */
interface StoreInterface {

  /**
   * Locates a cached Response for the Request provided.
   *
   * @param Request $request A Request instance
   *
   * @return Response|null A Response instance, or null if no cache entry was found
   */
  public function lookup(Request $request);

  /**
   * Writes a cache entry to the store for the given Request and Response.
   *
   * Existing entries are read and any that match the response are removed. This
   * method calls write with the new list of cache entries.
   *
   * @param Request  $request  A Request instance
   * @param Response $response A Response instance
   *
   * @return string The key under which the response is stored
   */
  public function write(Request $request, Response $response);

  /**
   * Invalidates all cache entries that match the request.
   *
   * @param Request $request A Request instance
   */
  public function invalidate(Request $request);

  /**
   * Locks the cache for a given Request.
   *
   * @param Request $request A Request instance
   *
   * @return Boolean|string true if the lock is acquired, the path to the current lock otherwise
   */
  public function lock(Request $request);

  /**
   * Releases the lock for the given Request.
   *
   * @param Request $request A Request instance
   *
   * @return Boolean False if the lock file does not exist or cannot be unlocked, true otherwise
   */
  public function unlock(Request $request);

  /**
   * Returns whether or not a lock exists.
   *
   * @param Request $request A Request instance
   *
   * @return Boolean true if lock exists, false otherwise
   */
  public function isLocked(Request $request);

  /**
   * Purges data for the given URL.
   *
   * @param string $url A URL
   *
   * @return Boolean true if the URL exists and has been purged, false otherwise
   */
  public function purge($url);

  /**
   * Cleanups storage.
   */
  public function cleanup();

}