symfony/tests/Symfony/Tests/Component/HttpKernel/Cache/CacheTest.php

<?php

/*
 * This file is part of the symfony package.
 *
 * (c) Fabien Potencier <fabien.potencier@symfony-project.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Tests\Component\HttpKernel\Cache;

require_once __DIR__.'/CacheTestCase.php';

class CacheTest extends CacheTestCase
{
    public function testPassesOnNonGetHeadRequests()
    {
        $this->setNextResponse(200);
        $this->request('POST', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertResponseOk();
        $this->assertTraceContains('pass');
        $this->assertFalse($this->response->headers->has('Age'));
    }

    public function testInvalidatesOnPostPutDeleteRequests()
    {
        foreach (array('post', 'put', 'delete') as $method) {
            $this->setNextResponse(200);
            $this->request($method, '/');

            $this->assertHttpKernelIsCalled();
            $this->assertResponseOk();
            $this->assertTraceContains('invalidate');
            $this->assertTraceContains('pass');
        }
    }

    public function testDoesNotCacheWithAuthorizationRequestHeaderAndNonPublicResponse()
    {
        $this->setNextResponse(200, array('ETag' => '"Foo"'));
        $this->request('GET', '/', array('HTTP_AUTHORIZATION' => 'basic foobarbaz'));

        $this->assertHttpKernelIsCalled();
        $this->assertResponseOk();
        $this->assertEquals('private', $this->response->headers->get('Cache-Control'));

        $this->assertTraceContains('miss');
        $this->assertTraceNotContains('store');
        $this->assertFalse($this->response->headers->has('Age'));
    }

    public function testDoesCacheWithAuthorizationRequestHeaderAndPublicResponse()
    {
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'ETag' => '"Foo"'));
        $this->request('GET', '/', array('HTTP_AUTHORIZATION' => 'basic foobarbaz'));

        $this->assertHttpKernelIsCalled();
        $this->assertResponseOk();
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertTrue($this->response->headers->has('Age'));
        $this->assertEquals('public', $this->response->headers->get('Cache-Control'));
    }

    public function testDoesNotCacheWithCookieHeaderAndNonPublicResponse()
    {
        $this->setNextResponse(200, array('ETag' => '"Foo"'));
        $this->request('GET', '/', array(), array('foo' => 'bar'));

        $this->assertHttpKernelIsCalled();
        $this->assertResponseOk();
        $this->assertEquals('private', $this->response->headers->get('Cache-Control'));
        $this->assertTraceContains('miss');
        $this->assertTraceNotContains('store');
        $this->assertFalse($this->response->headers->has('Age'));
    }

    public function testDoesNotCacheRequestsWithACookieHeader()
    {
        $this->setNextResponse(200);
        $this->request('GET', '/', array(), array('foo' => 'bar'));

        $this->assertHttpKernelIsCalled();
        $this->assertResponseOk();
        $this->assertEquals('private', $this->response->headers->get('Cache-Control'));
        $this->assertTraceContains('miss');
        $this->assertTraceNotContains('store');
        $this->assertFalse($this->response->headers->has('Age'));
    }

    public function testRespondsWith304WhenIfModifiedSinceMatchesLastModified()
    {
        $time = new \DateTime();

        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Last-Modified' => $time->format(DATE_RFC2822), 'Content-Type' => 'text/plain'), 'Hello World');
        $this->request('GET', '/', array('HTTP_IF_MODIFIED_SINCE' => $time->format(DATE_RFC2822)));

        $this->assertHttpKernelIsCalled();
        $this->assertEquals(304, $this->response->getStatusCode());
        $this->assertFalse($this->response->headers->has('Content-Length'));
        $this->assertFalse($this->response->headers->has('Content-Type'));
        $this->assertEmpty($this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
    }

    public function testRespondsWith304WhenIfNoneMatchMatchesETag()
    {
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'ETag' => '12345', 'Content-Type' => 'text/plain'), 'Hello World');
        $this->request('GET', '/', array('HTTP_IF_NONE_MATCH' => '12345'));

        $this->assertHttpKernelIsCalled();
        $this->assertEquals(304, $this->response->getStatusCode());
        $this->assertFalse($this->response->headers->has('Content-Length'));
        $this->assertFalse($this->response->headers->has('Content-Type'));
        $this->assertTrue($this->response->headers->has('ETag'));
        $this->assertEmpty($this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
    }

    public function testRespondsWith304OnlyIfIfNoneMatchAndIfModifiedSinceBothMatch()
    {
        $time = new \DateTime();

        $this->setNextResponse(200, array(), '', function ($request, $response) use ($time)
        {
            $response->setStatusCode(200);
            $response->headers->set('ETag', '12345');
            $response->headers->set('Last-Modified', $time->format(DATE_RFC2822));
            $response->headers->set('Content-Type', 'text/plain');
            $response->setContent('Hello World');
        });

        // only ETag matches
        $t = \DateTime::createFromFormat('U', time() - 3600);
        $this->request('GET', '/', array('HTTP_IF_NONE_MATCH' => '12345', 'HTTP_IF_MODIFIED_SINCE' => $t->format(DATE_RFC2822)));
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());

        // only Last-Modified matches
        $this->request('GET', '/', array('HTTP_IF_NONE_MATCH' => '1234', 'HTTP_IF_MODIFIED_SINCE' => $time->format(DATE_RFC2822)));
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());

        // Both matches
        $this->request('GET', '/', array('HTTP_IF_NONE_MATCH' => '12345', 'HTTP_IF_MODIFIED_SINCE' => $time->format(DATE_RFC2822)));
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(304, $this->response->getStatusCode());
    }

    public function testValidatesPrivateResponsesCachedOnTheClient()
    {
        $this->setNextResponse(200, array(), '', function ($request, $response)
        {
            $etags = preg_split('/\s*,\s*/', $request->headers->get('IF_NONE_MATCH'));
            if ($request->cookies->has('authenticated')) {
                $response->headers->set('Cache-Control', 'private, no-store');
                $response->setETag('"private tag"');
                if (in_array('"private tag"', $etags)) {
                    $response->setStatusCode(304);
                } else {
                    $response->setStatusCode(200);
                    $response->headers->set('Content-Type', 'text/plain');
                    $response->setContent('private data');
                }
            } else {
                $response->setETag('"public tag"');
                if (in_array('"public tag"', $etags)) {
                    $response->setStatusCode(304);
                } else {
                    $response->setStatusCode(200);
                    $response->headers->set('Content-Type', 'text/plain');
                    $response->setContent('public data');
                }
            }
        });

        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('"public tag"', $this->response->headers->get('ETag'));
        $this->assertEquals('public data', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        $this->request('GET', '/', array(), array('authenticated' => ''));
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('"private tag"', $this->response->headers->get('ETag'));
        $this->assertEquals('private data', $this->response->getContent());
        $this->assertTraceContains('stale');
        $this->assertTraceContains('invalid');
        $this->assertTraceNotContains('store');
    }

    public function testStoresResponsesWhenNoCacheRequestDirectivePresent()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);

        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Expires' => $time->format(DATE_RFC2822)));
        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'no-cache'));

        $this->assertHttpKernelIsCalled();
        $this->assertTraceContains('store');
        $this->assertTrue($this->response->headers->has('Age'));
    }

    public function testReloadsResponsesWhenCacheHitsButNoCacheRequestDirectivePresentWhenAllowReloadIsSetTrue()
    {
        $count = 0;

        $this->setNextResponse(200, array('Cache-Control' => 'public, max-age=10000'), '', function ($request, $response) use (&$count)
        {
            ++$count;
            $response->setContent(1 == $count ? 'Hello World' : 'Goodbye World');
        });

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('store');

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('fresh');

        $this->cacheConfig['allow_reload'] = true;
        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'no-cache'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Goodbye World', $this->response->getContent());
        $this->assertTraceContains('reload');
        $this->assertTraceContains('store');
    }

    public function testDoesNotReloadResponsesWhenAllowReloadIsSetFalseDefault()
    {
        $count = 0;

        $this->setNextResponse(200, array('Cache-Control' => 'public, max-age=10000'), '', function ($request, $response) use (&$count)
        {
            ++$count;
            $response->setContent(1 == $count ? 'Hello World' : 'Goodbye World');
        });

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('store');

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('fresh');

        $this->cacheConfig['allow_reload'] = false;
        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'no-cache'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceNotContains('reload');

        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'no-cache'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceNotContains('reload');
    }

    public function testRevalidatesFreshCacheEntryWhenMaxAgeRequestDirectiveIsExceededWhenAllowRevalidateOptionIsSetTrue()
    {
        $count = 0;

        $this->setNextResponse(200, array(), '', function ($request, $response) use (&$count)
        {
            ++$count;
            $response->headers->set('Cache-Control', 'public, max-age=10000');
            $response->setETag($count);
            $response->setContent(1 == $count ? 'Hello World' : 'Goodbye World');
        });

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('store');

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('fresh');

        $this->cacheConfig['allow_revalidate'] = true;
        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'max-age=0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Goodbye World', $this->response->getContent());
        $this->assertTraceContains('stale');
        $this->assertTraceContains('invalid');
        $this->assertTraceContains('store');
    }

    public function testDoesNotRevalidateFreshCacheEntryWhenEnableRevalidateOptionIsSetFalseDefault()
    {
        $count = 0;

        $this->setNextResponse(200, array(), '', function ($request, $response) use (&$count)
        {
            ++$count;
            $response->headers->set('Cache-Control', 'public, max-age=10000');
            $response->setETag($count);
            $response->setContent(1 == $count ? 'Hello World' : 'Goodbye World');
        });

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('store');

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('fresh');

        $this->cacheConfig['allow_revalidate'] = false;
        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'max-age=0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceNotContains('stale');
        $this->assertTraceNotContains('invalid');
        $this->assertTraceContains('fresh');

        $this->request('GET', '/', array('HTTP_CACHE_CONTROL' => 'max-age=0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceNotContains('stale');
        $this->assertTraceNotContains('invalid');
        $this->assertTraceContains('fresh');
    }

    public function testFetchesResponseFromBackendWhenCacheMisses()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Expires' => $time->format(DATE_RFC2822)));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertTraceContains('miss');
        $this->assertTrue($this->response->headers->has('Age'));
    }

    public function testDoesNotCacheSomeStatusCodeResponses()
    {
        foreach (array_merge(range(201, 202), range(204, 206), range(303, 305), range(400, 403), range(405, 409), range(411, 417), range(500, 505)) as $code) {
            $time = \DateTime::createFromFormat('U', time() + 5);
            $this->setNextResponse($code, array('Expires' => $time->format(DATE_RFC2822)));

            $this->request('GET', '/');
            $this->assertEquals($code, $this->response->getStatusCode());
            $this->assertTraceNotContains('store');
            $this->assertFalse($this->response->headers->has('Age'));
        }
    }

    public function testDoesNotCacheResponsesWithExplicitNoStoreDirective()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Expires' => $time->format(DATE_RFC2822), 'Cache-Control' => 'no-store'));

        $this->request('GET', '/');
        $this->assertTraceNotContains('store');
        $this->assertFalse($this->response->headers->has('Age'));
    }

    public function testDoesNotCacheResponsesWithoutFreshnessInformationOrAValidator()
    {
        $this->setNextResponse();

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertTraceNotContains('store');
    }

    public function testCachesResponesWithExplicitNoCacheDirective()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Expires' => $time->format(DATE_RFC2822), 'Cache-Control' => 'public, no-cache'));

        $this->request('GET', '/');
        $this->assertTraceContains('store');
        $this->assertTrue($this->response->headers->has('Age'));
    }

    public function testCachesResponsesWithAnExpirationHeader()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Expires' => $time->format(DATE_RFC2822)));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        $values = $this->getMetaStorageValues();
        $this->assertEquals(1, count($values));
    }

    public function testCachesResponsesWithAMaxAgeDirective()
    {
        $this->setNextResponse(200, array('Cache-Control' => 'public, max-age=5'));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        $values = $this->getMetaStorageValues();
        $this->assertEquals(1, count($values));
    }

    public function testCachesResponsesWithASMaxAgeDirective()
    {
        $this->setNextResponse(200, array('Cache-Control' => 's-maxage=5'));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        $values = $this->getMetaStorageValues();
        $this->assertEquals(1, count($values));
    }

    public function testCachesResponsesWithALastModifiedValidatorButNoFreshnessInformation()
    {
        $time = \DateTime::createFromFormat('U', time());
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Last-Modified' => $time->format(DATE_RFC2822)));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
    }

    public function testCachesResponsesWithAnETagValidatorButNoFreshnessInformation()
    {
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'ETag' => '"123456"'));

        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
    }

    public function testHitsCachedResponsesWithExpiresHeader()
    {
        $time1 = \DateTime::createFromFormat('U', time() - 5);
        $time2 = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Date' => $time1->format(DATE_RFC2822), 'Expires' => $time2->format(DATE_RFC2822)));

        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());

        $this->request('GET', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals($this->responses[0]->headers->get('Date'), $this->response->headers->get('Date'));
        $this->assertTrue($this->response->headers->get('Age') > 0);
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('fresh');
        $this->assertTraceNotContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testHitsCachedResponseWithMaxAgeDirective()
    {
        $time = \DateTime::createFromFormat('U', time() - 5);
        $this->setNextResponse(200, array('Date' => $time->format(DATE_RFC2822), 'Cache-Control' => 'public, max-age=10'));

        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());

        $this->request('GET', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals($this->responses[0]->headers->get('Date'), $this->response->headers->get('Date'));
        $this->assertTrue($this->response->headers->get('Age') > 0);
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('fresh');
        $this->assertTraceNotContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testHitsCachedResponseWithSMaxAgeDirective()
    {
        $time = \DateTime::createFromFormat('U', time() - 5);
        $this->setNextResponse(200, array('Date' => $time->format(DATE_RFC2822), 'Cache-Control' => 's-maxage=10, max-age=0'));

        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());

        $this->request('GET', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals($this->responses[0]->headers->get('Date'), $this->response->headers->get('Date'));
        $this->assertTrue($this->response->headers->get('Age') > 0);
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('fresh');
        $this->assertTraceNotContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testAssignsDefaultTtlWhenResponseHasNoFreshnessInformation()
    {
        $this->setNextResponse();

        $this->cacheConfig['default_ttl'] = 10;
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertRegExp('/s-maxage=10/', $this->response->headers->get('Cache-Control'));

        $this->cacheConfig['default_ttl'] = 10;
        $this->request('GET', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertTraceContains('fresh');
        $this->assertTraceNotContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testDoesNotAssignDefaultTtlWhenResponseHasMustRevalidateDirective()
    {
        $this->setNextResponse(200, array('Cache-Control' => 'must-revalidate'));

        $this->cacheConfig['default_ttl'] = 10;
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertTraceContains('miss');
        $this->assertTraceNotContains('store');
        $this->assertNotRegExp('/s-maxage/', $this->response->headers->get('Cache-Control'));
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testFetchesFullResponseWhenCacheStaleAndNoValidatorsPresent()
    {
        $time = \DateTime::createFromFormat('U', time() + 5);
        $this->setNextResponse(200, array('Cache-Control' => 'public', 'Expires' => $time->format(DATE_RFC2822)));

        // build initial request
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Date'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertNotNull($this->response->headers->get('Age'));
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());

        # go in and play around with the cached metadata directly ...
        $values = $this->getMetaStorageValues();
        $this->assertEquals(1, count($values));
        $tmp = unserialize($values[0]);
        $time = \DateTime::createFromFormat('U', time());
        $tmp[0][1]['expires'] = $time->format(DATE_RFC2822);
        $this->store->save('md'.sha1('http://localhost/'), serialize($tmp));

        // build subsequent request; should be found but miss due to freshness
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals(0, $this->response->headers->get('Age'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertTraceContains('stale');
        $this->assertTraceNotContains('fresh');
        $this->assertTraceNotContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Hello World', $this->response->getContent());
    }

    public function testValidatesCachedResponsesWithLastModifiedAndNoFreshnessInformation()
    {
        $time = \DateTime::createFromFormat('U', time());
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response) use ($time)
        {
            $response->headers->set('Cache-Control', 'public');
            $response->headers->set('Last-Modified', $time->format(DATE_RFC2822));
            if ($time->format(DATE_RFC2822) == $request->headers->get('IF_MODIFIED_SINCE')) {
                $response->setStatusCode(304);
                $response->setContent('');
            }
        });

        // build initial request
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Last-Modified'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertTraceNotContains('stale');

        // build subsequent request; should be found but miss due to freshness
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('Last-Modified'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertEquals(0, $this->response->headers->get('Age'));
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('stale');
        $this->assertTraceContains('valid');
        $this->assertTraceContains('store');
        $this->assertTraceNotContains('miss');
    }

    public function testValidatesCachedResponsesWithETagAndNoFreshnessInformation()
    {
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response)
        {
            $response->headers->set('Cache-Control', 'public');
            $response->headers->set('ETag', '"12345"');
            if ($response->getETag() == $request->headers->get('IF_NONE_MATCH')) {
                $response->setStatusCode(304);
                $response->setContent('');
            }
        });

        // build initial request
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('ETag'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        // build subsequent request; should be found but miss due to freshness
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertNotNull($this->response->headers->get('ETag'));
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
        $this->assertEquals(0, $this->response->headers->get('Age'));
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('stale');
        $this->assertTraceContains('valid');
        $this->assertTraceContains('store');
        $this->assertTraceNotContains('miss');
    }

    public function testReplacesCachedResponsesWhenValidationResultsInNon304Response()
    {
        $time = \DateTime::createFromFormat('U', time());
        $count = 0;
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response) use ($time, &$count)
        {
            $response->headers->set('Last-Modified', $time->format(DATE_RFC2822));
            switch (++$count) {
                case 1:
                    $response->setContent('first response');
                    break;
                case 2:
                    $response->setContent('second response');
                    break;
                case 3:
                    $response->setContent('');
                    $response->setStatusCode(304);
                    break;
            }
        });

        // first request should fetch from backend and store in cache
        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('first response', $this->response->getContent());

        // second request is validated, is invalid, and replaces cached entry
        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('second response', $this->response->getContent());

        // third response is validated, valid, and returns cached entry
        $this->request('GET', '/');
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('second response', $this->response->getContent());

        $this->assertEquals(3, $count);
    }

    public function testPassesHeadRequestsThroughDirectlyOnPass()
    {
        $that = $this;
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response) use ($that)
        {
            $response->setContent('');
            $response->setStatusCode(200);
            $that->assertEquals('HEAD', $request->getMethod());
        });

        $this->request('HEAD', '/', array('HTTP_EXPECT' => 'something ...'));
        $this->assertHttpKernelIsCalled();
        $this->assertEquals('', $this->response->getContent());
    }

    public function testUsesCacheToRespondToHeadRequestsWhenFresh()
    {
        $that = $this;
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response) use ($that)
        {
            $response->headers->set('Cache-Control', 'public, max-age=10');
            $response->setContent('Hello World');
            $response->setStatusCode(200);
            $that->assertNotEquals('HEAD', $request->getMethod());
        });

        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals('Hello World', $this->response->getContent());

        $this->request('HEAD', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('', $this->response->getContent());
        $this->assertEquals(strlen('Hello World'), $this->response->headers->get('Content-Length'));
    }

    public function testInvalidatesCachedResponsesOnPost()
    {
        $this->setNextResponse(200, array(), 'Hello World', function ($request, $response)
        {
            if ('GET' == $request->getMethod()) {
                $response->setStatusCode(200);
                $response->headers->set('Cache-Control', 'public, max-age=500');
                $response->setContent('Hello World');
            } elseif ('POST' == $request->getMethod()) {
                $response->setStatusCode(303);
                $response->headers->set('Location', '/');
                $response->headers->remove('Cache-Control');
                $response->setContent('');
            }
        });

        // build initial request to enter into the cache
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        // make sure it is valid
        $this->request('GET', '/');
        $this->assertHttpKernelIsNotCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('fresh');

        // now POST to same URL
        $this->request('POST', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals('/', $this->response->headers->get('Location'));
        $this->assertTraceContains('invalidate');
        $this->assertTraceContains('pass');
        $this->assertEquals('', $this->response->getContent());

        // now make sure it was actually invalidated
        $this->request('GET', '/');
        $this->assertHttpKernelIsCalled();
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Hello World', $this->response->getContent());
        $this->assertTraceContains('stale');
        $this->assertTraceContains('invalid');
        $this->assertTraceContains('store');
    }

    public function testServesFromCacheWhenHeadersMatch()
    {
        $count = 0;
        $this->setNextResponse(200, array('Cache-Control' => 'max-age=10000'), '', function ($request, $response) use (&$count)
        {
            $response->headers->set('Vary', 'Accept User-Agent Foo');
            $response->headers->set('Cache-Control', 'public, max-age=10');
            $response->headers->set('X-Response-Count', ++$count);
            $response->setContent($request->headers->get('USER_AGENT'));
        });

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/1.0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Bob/1.0', $this->response->getContent());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/1.0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Bob/1.0', $this->response->getContent());
        $this->assertTraceContains('fresh');
        $this->assertTraceNotContains('store');
        $this->assertNotNull($this->response->headers->get('X-Content-Digest'));
    }

    public function testStoresMultipleResponsesWhenHeadersDiffer()
    {
        $count = 0;
        $this->setNextResponse(200, array('Cache-Control' => 'max-age=10000'), '', function ($request, $response) use (&$count)
        {
            $response->headers->set('Vary', 'Accept User-Agent Foo');
            $response->headers->set('Cache-Control', 'public, max-age=10');
            $response->headers->set('X-Response-Count', ++$count);
            $response->setContent($request->headers->get('USER_AGENT'));
        });

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/1.0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertEquals('Bob/1.0', $this->response->getContent());
        $this->assertEquals(1, $this->response->headers->get('X-Response-Count'));

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/2.0'));
        $this->assertEquals(200, $this->response->getStatusCode());
        $this->assertTraceContains('miss');
        $this->assertTraceContains('store');
        $this->assertEquals('Bob/2.0', $this->response->getContent());
        $this->assertEquals(2, $this->response->headers->get('X-Response-Count'));

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/1.0'));
        $this->assertTraceContains('fresh');
        $this->assertEquals('Bob/1.0', $this->response->getContent());
        $this->assertEquals(1, $this->response->headers->get('X-Response-Count'));

        $this->request('GET', '/', array('HTTP_ACCEPT' => 'text/html', 'HTTP_USER_AGENT' => 'Bob/2.0'));
        $this->assertTraceContains('fresh');
        $this->assertEquals('Bob/2.0', $this->response->getContent());
        $this->assertEquals(2, $this->response->headers->get('X-Response-Count'));

        $this->request('GET', '/', array('HTTP_USER_AGENT' => 'Bob/2.0'));
        $this->assertTraceContains('miss');
        $this->assertEquals('Bob/2.0', $this->response->getContent());
        $this->assertEquals(3, $this->response->headers->get('X-Response-Count'));
    }
}