/**
* Check if an already cached request must be revalidated, and if so update
* the request with the correct ETag headers.
* @param HttpRequest $cached A previously cached response.
* @param HttpRequest $request The outbound request.
* return bool If the cached object needs to be revalidated, false if it is
* still current and can be re-used.
*/
protected function checkMustRevaliadateCachedRequest($cached, $request)
{
if (Google_CacheParser::mustRevalidate($cached)) {
$addHeaders = array();
if ($cached->getResponseHeader('etag')) {
// [13.3.4] If an entity tag has been provided by the origin server,
// we must use that entity tag in any cache-conditional request.
$addHeaders['If-None-Match'] = $cached->getResponseHeader('etag');
} elseif ($cached->getResponseHeader('date')) {
$addHeaders['If-Modified-Since'] = $cached->getResponseHeader('date');
}
$request->setRequestHeaders($addHeaders);
return true;
} else {
return false;
}
}
/**
* @visible for testing.
* @param Google_HttpRequest $request
* @return Google_HttpRequest|bool Returns the cached object or
* false if the operation was unsuccessful.
*/
public function getCachedRequest(Google_HttpRequest $request)
{
if (false == Google_CacheParser::isRequestCacheable($request)) {
false;
}
return Google_Client::$cache->get($request->getCacheKey());
}
public function testMustRevalidate()
{
$now = time();
// Expires 1 year in the future, and contains the must-revalidate directive.
// Don't revalidate. must-revalidate only applies to expired entries.
$future = $now + 365 * 24 * 60 * 60;
$resp = new Google_HttpRequest('http://localhost', 'GET');
$resp->setResponseHttpCode('200');
$resp->setResponseHeaders(array('Cache-Control' => 'max-age=3600, must-revalidate', 'Expires' => gmdate('D, d M Y H:i:s', $future) . ' GMT', 'Date' => gmdate('D, d M Y H:i:s', $now) . ' GMT'));
$this->assertFalse(Google_CacheParser::mustRevalidate($resp));
// Contains the max-age=3600 directive, but was created 2 hours ago.
// Must revalidate.
$past = $now - 2 * 60 * 60;
$resp = new Google_HttpRequest('http://localhost', 'GET');
$resp->setResponseHttpCode('200');
$resp->setResponseHeaders(array('Cache-Control' => 'max-age=3600', 'Expires' => gmdate('D, d M Y H:i:s', $future) . ' GMT', 'Date' => gmdate('D, d M Y H:i:s', $past) . ' GMT'));
$this->assertTrue(Google_CacheParser::mustRevalidate($resp));
// Contains the max-age=3600 directive, and was created 600 seconds ago.
// No need to revalidate, regardless of the expires header.
$past = $now - 600;
$resp = new Google_HttpRequest('http://localhost', 'GET');
$resp->setResponseHttpCode('200');
$resp->setResponseHeaders(array('Cache-Control' => 'max-age=3600', 'Expires' => gmdate('D, d M Y H:i:s', $past) . ' GMT', 'Date' => gmdate('D, d M Y H:i:s', $past) . ' GMT'));
$this->assertFalse(Google_CacheParser::mustRevalidate($resp));
}