cache.rst

@Cache

The @Cache annotation makes it easy to define HTTP caching headers for expiration and validation.

HTTP Expiration Strategies

The @Cache annotation makes it easy to define HTTP caching:

use Sensio\Bundle\FrameworkExtraBundle\Configuration\Cache;

/**
 * @Cache(expires="tomorrow", public=true)
 */
public function index()
{
}

You can also use the annotation on a class to define caching for all actions of a controller:

/**
 * @Cache(expires="tomorrow", public=true)
 */
class BlogController extends Controller
{
}

When there is a conflict between the class configuration and the method configuration, the latter overrides the former:

/**
 * @Cache(expires="tomorrow")
 */
class BlogController extends Controller
{
    /**
     * @Cache(expires="+2 days")
     */
    public function index()
    {
    }
}

Note

The expires attribute takes any valid date understood by the PHP strtotime() function.

HTTP Validation Strategies

The lastModified and Etag attributes manage the HTTP validation cache headers. lastModified adds a Last-Modified header to Responses and Etag adds an Etag header.

Both automatically trigger the logic to return a 304 response when the response is not modified (in this case, the controller is not called):

use Sensio\Bundle\FrameworkExtraBundle\Configuration\Cache;

/**
 * @Cache(lastModified="post.getUpdatedAt()", Etag="'Post' ~ post.getId() ~ post.getUpdatedAt().getTimestamp()")
 */
public function index(Post $post)
{
    // your code
    // won't be called in case of a 304
}

It's roughly doing the same as the following code:

public function my(Request $request, Post $post)
{
    $response = new Response();
    $response->setLastModified($post->getUpdatedAt());
    if ($response->isNotModified($request)) {
        return $response;
    }

    // your code
}

Note

The Etag HTTP header value is the result of the expression hashed with the sha256 algorithm.

Attributes

Here is a list of accepted attributes and their HTTP header equivalent:

Annotation	Response Method
@Cache(expires="tomorrow")	$response->setExpires()
@Cache(smaxage="15")	$response->setSharedMaxAge()
@Cache(maxage="15")	$response->setMaxAge()
@Cache(maxstale="15")	$response->headers->addCacheControlDirective('max-stale', 15)
@Cache(vary={"Cookie"})	$response->setVary()
@Cache(public=true)	$response->setPublic()
@Cache(lastModified="post.getUpdatedAt()")	$response->setLastModified()
@Cache(Etag="post.getId() ~ post.getUpdatedAt().getTimestamp()")	$response->setEtag()
@Cache(mustRevalidate=true)	$response->headers->addCacheControlDirective('must-revalidate')

Note

smaxage, maxage and maxstale attributes can also get a string with relative time format (1 day, 2 weeks, ...).