class ResponseCacheStrategy in Zircon Profile 8

ResponseCacheStrategy knows how to compute the Response cache HTTP header based on the different response cache headers.

This implementation changes the master response TTL to the smallest TTL received or force validation if one of the surrogates has validation cache strategy.

@author Fabien Potencier <[e-mail]>

Hierarchy

• class \Symfony\Component\HttpKernel\HttpCache\ResponseCacheStrategy implements ResponseCacheStrategyInterface

File

vendor/symfony/http-kernel/HttpCache/ResponseCacheStrategy.php, line 29

Namespace

Symfony\Component\HttpKernel\HttpCache

class ResponseCacheStrategy implements ResponseCacheStrategyInterface {
  private $cacheable = true;
  private $embeddedResponses = 0;
  private $ttls = array();
  private $maxAges = array();

  /**
   * {@inheritdoc}
   */
  public function add(Response $response) {
    if ($response
      ->isValidateable()) {
      $this->cacheable = false;
    }
    else {
      $this->ttls[] = $response
        ->getTtl();
      $this->maxAges[] = $response
        ->getMaxAge();
    }
    ++$this->embeddedResponses;
  }

  /**
   * {@inheritdoc}
   */
  public function update(Response $response) {

    // if we have no embedded Response, do nothing
    if (0 === $this->embeddedResponses) {
      return;
    }

    // Remove validation related headers in order to avoid browsers using
    // their own cache, because some of the response content comes from
    // at least one embedded response (which likely has a different caching strategy).
    if ($response
      ->isValidateable()) {
      $response
        ->setEtag(null);
      $response
        ->setLastModified(null);
      $this->cacheable = false;
    }
    if (!$this->cacheable) {
      $response->headers
        ->set('Cache-Control', 'no-cache, must-revalidate');
      return;
    }
    $this->ttls[] = $response
      ->getTtl();
    $this->maxAges[] = $response
      ->getMaxAge();
    if (null !== ($maxAge = min($this->maxAges))) {
      $response
        ->setSharedMaxAge($maxAge);
      $response->headers
        ->set('Age', $maxAge - min($this->ttls));
    }
    $response
      ->setMaxAge(0);
  }

}

Members

Name	Modifiers	Type	Description	Overrides
ResponseCacheStrategy::$cacheable	private	property
ResponseCacheStrategy::$embeddedResponses	private	property
ResponseCacheStrategy::$maxAges	private	property
ResponseCacheStrategy::$ttls	private	property
ResponseCacheStrategy::add	public	function	Adds a Response. Overrides ResponseCacheStrategyInterface::add
ResponseCacheStrategy::update	public	function	Updates the Response HTTP headers based on the embedded Responses. Overrides ResponseCacheStrategyInterface::update