/**
* Check Cache
*
* Checks the browser cache to see the response needs to be returned
*
* @param string $etag Resource ETag [Optional]
* @param Request $request The request to test against [Optional]
*
* @return Response
*
* @throws Request_Exception
*/
public function check_cache($etag = NULL, Request $request = NULL)
{
if (!$etag) {
$etag = $this->generate_etag();
}
if (!$request) {
throw new Request_Exception('A Request object must be supplied with an etag for evaluation');
}
// Set the ETag header
$this->_header['etag'] = $etag;
// Add the Cache-Control header if it is not already set
// This allows etags to be used with max-age, etc
if ($this->_header->offsetExists('cache-control')) {
if (is_array($this->_header['cache-control'])) {
// @todo
$this->_header['cache-control'][] = new HTTP_Header_Value('must-revalidate');
} else {
$this->_header['cache-control'] = $this->_header['cache-control'] . ', must-revalidate';
}
} else {
$this->_header['cache-control'] = 'must-revalidate';
}
if ($request->headers('if-none-match') and (string) $request->headers('if-none-match') === $etag) {
// No need to send data again
$this->_status = 304;
$this->send_headers();
// Stop execution
exit;
}
return $this;
}
public function test_offsetExists(array $state, $key, $expected)
{
$header = new HTTP_Header($state);
$this->assertSame($expected, $header->offsetExists($key));
}
/**
* Gets or sets HTTP headers to the request or response. All headers
* are included immediately after the HTTP protocol definition during
* transmission. This method provides a simple array or key/value
* interface to the headers.
*
* @param mixed $key Key or array of key/value pairs to set
* @param string $value Value to set to the supplied key
*
* @return Request|HTTP_Header|mixed
*/
public function headers($key = NULL, $value = NULL)
{
if ($key instanceof HTTP_Header) {
// Act a setter, replace all headers
$this->_header = $key;
return $this;
}
if (is_array($key)) {
// Act as a setter, replace all headers
$this->_header->exchangeArray($key);
return $this;
}
if ($this->_header->count() === 0 and $this->is_initial()) {
// Lazy load the request headers
$this->_header = HTTP::request_headers();
}
if ($key === NULL) {
// Act as a getter, return all headers
return $this->_header;
} elseif ($value === NULL) {
// Act as a getter, single header
return $this->_header->offsetExists($key) ? $this->_header->offsetGet($key) : NULL;
}
// Act as a setter for a single header
$this->_header[$key] = $value;
return $this;
}