Request Client
Class declared in SYSPATH/classes/request/client.php on line 3.
boolean $_allow_private_cacheDefines whether this client should cache private cache directives
Cache $_cacheCaching library for request caching
int $_request_timeThe timestamp of the request
int $_response_timeThe timestamp of the response
Creates a new Request_Client object,
allows for dependency injection.
array
$params
= array(0) - Paramspublic function __construct(array $params = array())
{
if ($params)
{
foreach ($params as $key => $value)
{
if (method_exists($this, $key))
{
if (property_exists($this, $key) OR property_exists($this, '_'.$key))
{
$method = trim($key, '_');
$this->$method($value);
}
}
}
}
}Gets or sets the Request_Client::allow_private_cache setting.
If set to TRUE, the client will also cache cache-control directives
that have the private setting.
boolean
$setting
= NULL - Allow caching of privately marked responsesboolean[Request_Client]public function allow_private_cache($setting = NULL)
{
if ($setting === NULL)
return $this->_allow_private_cache;
$this->_allow_private_cache = (bool) $setting;
return $this;
}Getter and setter for the internal caching engine, used to cache responses if available and valid.
Kohana_Cache
$cache
= NULL - Cache engine to use for cachingKohana_CacheKohana_Request_Clientpublic function cache(Cache $cache = NULL)
{
if ($cache === NULL)
return $this->_cache;
$this->_cache = $cache;
return $this;
}Calculates the total Time To Live based on the specification RFC 2616 cache lifetime rules.
Response
$response
required - Response to evaluatemixed - TTL value or false if the response should not be cachedpublic function cache_lifetime(Response $response)
{
// Get out of here if this cannot be cached
if ( ! $this->set_cache($response))
return FALSE;
// Calculate apparent age
if ($date = $response->headers('date'))
{
$apparent_age = max(0, $this->_response_time - strtotime( (string) $date));
}
else
{
$apparent_age = max(0, $this->_response_time);
}
// Calculate corrected received age
if ($age = $response->headers('age'))
{
$corrected_received_age = max($apparent_age, intval( (string) $age));
}
else
{
$corrected_received_age = $apparent_age;
}
// Corrected initial age
$corrected_initial_age = $corrected_received_age + $this->request_execution_time();
// Resident time
$resident_time = time() - $this->_response_time;
// Current age
$current_age = $corrected_initial_age + $resident_time;
// Prepare the cache freshness lifetime
$ttl = NULL;
// Cache control overrides
if ($cache_control = $response->headers('cache-control'))
{
// Parse the cache control header
$cache_control = Response::parse_cache_control( (string) $cache_control);
if (isset($cache_control['max-age']))
{
$ttl = (int) $cache_control['max-age'];
}
if (isset($cache_control['s-maxage']) AND isset($cache_control['private']) AND $this->_allow_private_cache)
{
$ttl = (int) $cache_control['s-maxage'];
}
if (isset($cache_control['max-stale']) AND ! isset($cache_control['must-revalidate']))
{
$ttl = $current_age + (int) $cache_control['max-stale'];
}
}
// If we have a TTL at this point, return
if ($ttl !== NULL)
return $ttl;
if ($expires = $response->headers('expires'))
return strtotime( (string) $expires) - $current_age;
return FALSE;
}Caches a Response using the supplied Cache and the key generated by Request_Client::_create_cache_key.
If not response is supplied, the cache will be checked for an existing one that is available.
Request
$request
required - The requestResponse
$response
= NULL - Responsemixedpublic function cache_response(Request $request, Response $response = NULL)
{
if ( ! $this->_cache instanceof Cache)
return FALSE;
// Check for Pragma: no-cache
if ($pragma = $request->headers('pragma'))
{
if ($pragma instanceof HTTP_Header_Value and $pragma->key == 'no-cache')
return FALSE;
elseif (is_array($pragma) and isset($pragma['no-cache']))
return FALSE;
}
if ( ! $response)
{
$response = $this->_cache->get($this->create_cache_key($request));
return ($response !== NULL) ? $response : FALSE;
}
else
{
if (($ttl = $this->cache_lifetime($response)) === FALSE)
return FALSE;
return $this->_cache->set($this->create_cache_key($request), $response, $ttl);
}
}Creates a cache key for the request to use for caching Kohana_Response returned by Request::execute.
Request
$request
required - Requeststringbooleanpublic function create_cache_key(Request $request)
{
return sha1($request->url());
}Processes the request, executing the controller action that handles this request, determined by the Route.
By default, the output from the controller is captured and returned, and no headers are sent.
$request->execute();
Request
$request
required - $requestResponseabstract public function execute(Request $request);Invalidate a cached response for the Request supplied. This has the effect of deleting the response from the Cache entry.
Request
$request
required - Response to remove from cachevoidpublic function invalidate_cache(Request $request)
{
if ( ! $this->_cache instanceof Cache)
return;
$this->_cache->delete($this->_create_cache_key($request));
return;
}Returns the duration of the last request execution.
Either returns the time of completed requests or
FALSE if the request hasn't finished executing, or
is yet to be run.
mixedpublic function request_execution_time()
{
if ($this->_request_time === NULL OR $this->_response_time === NULL)
return FALSE;
return $this->_response_time - $this->_request_time;
}Controls whether the response can be cached. Uses HTTP protocol to determine whether the response can be cached.
Response
$response
required - The Responsebooleanpublic function set_cache(Response $response)
{
$headers = (array) $response->headers();
if ($cache_control = arr::get($headers, 'cache-control'))
{
// Parse the cache control
$cache_control = Response::parse_cache_control( (string) $cache_control);
// If the no-cache or no-store directive is set, return
if (array_intersect_key($cache_control, array('no-cache' => NULL, 'no-store' => NULL)))
return FALSE;
// Get the directives
$directives = array_keys($cache_control);
// Check for private cache and get out of here if invalid
if ( ! $this->_allow_private_cache and in_array('private', $directives))
{
if ( ! isset($cache_control['s-maxage']))
return FALSE;
// If there is a s-maxage directive we can use that
$cache_control['max-age'] = $cache_control['s-maxage'];
}
// Check that max-age has been set and if it is valid for caching
if (isset($cache_control['max-age']) and (int) $cache_control['max-age'] < 1)
return FALSE;
}
if ($expires = arr::get($headers, 'expires') and ! isset($cache_control['max-age']))
{
// Can't cache things that have expired already
if (strtotime( (string) $expires) <= time())
return FALSE;
}
return TRUE;
}