<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Wildfire
* @subpackage Channel
* @copyright Copyright (c) 2005-2014 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
* @version $Id$
*/
/** Zend_Wildfire_Channel_Interface */
require_once 'Zend/Wildfire/Channel/Interface.php';
/** Zend_Controller_Request_Abstract */
require_once('Zend/Controller/Request/Abstract.php');
/** Zend_Controller_Response_Abstract */
require_once('Zend/Controller/Response/Abstract.php');
/** Zend_Controller_Plugin_Abstract */
require_once 'Zend/Controller/Plugin/Abstract.php';
/** Zend_Wildfire_Protocol_JsonStream */
require_once 'Zend/Wildfire/Protocol/JsonStream.php';
/** Zend_Controller_Front **/
require_once 'Zend/Controller/Front.php';
/**
* Implements communication via HTTP request and response headers for Wildfire Protocols.
*
* @category Zend
* @package Zend_Wildfire
* @subpackage Channel
* @copyright Copyright (c) 2005-2014 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
class Zend_Wildfire_Channel_HttpHeaders extends Zend_Controller_Plugin_Abstract implements Zend_Wildfire_Channel_Interface
{
/**
* The string to be used to prefix the headers.
* @var string
*/
protected static $_headerPrefix = 'X-WF-';
/**
* Singleton instance
* @var Zend_Wildfire_Channel_HttpHeaders
*/
protected static $_instance = null;
/**
* The index of the plugin in the controller dispatch loop plugin stack
* @var integer
*/
protected static $_controllerPluginStackIndex = 999;
/**
* The protocol instances for this channel
* @var array
*/
protected $_protocols = null;
/**
* Initialize singleton instance.
*
* @param string $class OPTIONAL Subclass of Zend_Wildfire_Channel_HttpHeaders
* @return Zend_Wildfire_Channel_HttpHeaders Returns the singleton Zend_Wildfire_Channel_HttpHeaders instance
* @throws Zend_Wildfire_Exception
*/
public static function init($class = null)
{
if (self::$_instance !== null) {
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Singleton instance of Zend_Wildfire_Channel_HttpHeaders already exists!');
}
if ($class !== null) {
if (!is_string($class)) {
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Third argument is not a class string');
}
if (!class_exists($class)) {
require_once 'Zend/Loader.php';
Zend_Loader::loadClass($class);
}
self::$_instance = new $class();
if (!self::$_instance instanceof Zend_Wildfire_Channel_HttpHeaders) {
self::$_instance = null;
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Invalid class to third argument. Must be subclass of Zend_Wildfire_Channel_HttpHeaders.');
}
} else {
self::$_instance = new self();
}
return self::$_instance;
}
/**
* Get or create singleton instance
*
* @param bool $skipCreate True if an instance should not be created
* @return Zend_Wildfire_Channel_HttpHeaders
*/
public static function getInstance($skipCreate=false)
{
if (self::$_instance===null && $skipCreate!==true) {
return self::init();
}
return self::$_instance;
}
/**
* Destroys the singleton instance
*
* Primarily used for testing.
*
* @return void
*/
public static function destroyInstance()
{
self::$_instance = null;
}
/**
* Get the instance of a give protocol for this channel
*
* @param string $uri The URI for the protocol
* @return object Returns the protocol instance for the diven URI
*/
public function getProtocol($uri)
{
if (!isset($this->_protocols[$uri])) {
$this->_protocols[$uri] = $this->_initProtocol($uri);
}
$this->_registerControllerPlugin();
return $this->_protocols[$uri];
}
/**
* Initialize a new protocol
*
* @param string $uri The URI for the protocol to be initialized
* @return object Returns the new initialized protocol instance
* @throws Zend_Wildfire_Exception
*/
protected function _initProtocol($uri)
{
switch ($uri) {
case Zend_Wildfire_Protocol_JsonStream::PROTOCOL_URI;
return new Zend_Wildfire_Protocol_JsonStream();
}
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Tyring to initialize unknown protocol for URI "'.$uri.'".');
}
/**
* Flush all data from all protocols and send all data to response headers.
*
* @return boolean Returns TRUE if data was flushed
*/
public function flush()
{
if (!$this->_protocols || !$this->isReady()) {
return false;
}
foreach ( $this->_protocols as $protocol ) {
$payload = $protocol->getPayload($this);
if ($payload) {
foreach( $payload as $message ) {
$this->getResponse()->setHeader(self::$_headerPrefix.$message[0],
$message[1], true);
}
}
}
return true;
}
/**
* Set the index of the plugin in the controller dispatch loop plugin stack
*
* @param integer $index The index of the plugin in the stack
* @return integer The previous index.
*/
public static function setControllerPluginStackIndex($index)
{
$previous = self::$_controllerPluginStackIndex;
self::$_controllerPluginStackIndex = $index;
return $previous;
}
/**
* Register this object as a controller plugin.
*
* @return void
*/
protected function _registerControllerPlugin()
{
$controller = Zend_Controller_Front::getInstance();
if (!$controller->hasPlugin(get_class($this))) {
$controller->registerPlugin($this, self::$_controllerPluginStackIndex);
}
}
/*
* Zend_Wildfire_Channel_Interface
*/
/**
* Determine if channel is ready.
*
* The channel is ready as long as the request and response objects are initialized,
* can send headers and the FirePHP header exists in the User-Agent.
*
* If the header does not exist in the User-Agent, no appropriate client
* is making this request and the messages should not be sent.
*
* A timing issue arises when messages are logged before the request/response
* objects are initialized. In this case we do not yet know if the client
* will be able to accept the messages. If we consequently indicate that
* the channel is not ready, these messages will be dropped which is in
* most cases not the intended behaviour. The intent is to send them at the
* end of the request when the request/response objects will be available
* for sure.
*
* If the request/response objects are not yet initialized we assume if messages are
* logged, the client will be able to receive them. As soon as the request/response
* objects are availoable and a message is logged this assumption is challenged.
* If the client cannot accept the messages any further messages are dropped
* and messages sent prior are kept but discarded when the channel is finally
* flushed at the end of the request.
*
* When the channel is flushed the $forceCheckRequest option is used to force
* a check of the request/response objects. This is the last verification to ensure
* messages are only sent when the client can accept them.
*
* @param boolean $forceCheckRequest OPTIONAL Set to TRUE if the request must be checked
* @return boolean Returns TRUE if channel is ready.
*/
public function isReady($forceCheckRequest=false)
{
if (!$forceCheckRequest
&& !$this->_request
&& !$this->_response
) {
return true;
}
if (!($this->getRequest() instanceof Zend_Controller_Request_Http)) {
return false;
}
return ($this->getResponse()->canSendHeaders()
&& (preg_match_all(
'/\s?FirePHP\/([\.\d]*)\s?/si',
$this->getRequest()->getHeader('User-Agent'),
$m
) ||
(($header = $this->getRequest()->getHeader('X-FirePHP-Version'))
&& preg_match_all('/^([\.\d]*)$/si', $header, $m)
))
);
}
/*
* Zend_Controller_Plugin_Abstract
*/
/**
* Flush messages to headers as late as possible but before headers have been sent.
*
* @return void
*/
public function dispatchLoopShutdown()
{
$this->flush();
}
/**
* Get the request object
*
* @return Zend_Controller_Request_Abstract
* @throws Zend_Wildfire_Exception
*/
public function getRequest()
{
if (!$this->_request) {
$controller = Zend_Controller_Front::getInstance();
$this->setRequest($controller->getRequest());
}
if (!$this->_request) {
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Request objects not initialized.');
}
return $this->_request;
}
/**
* Get the response object
*
* @return Zend_Controller_Response_Abstract
* @throws Zend_Wildfire_Exception
*/
public function getResponse()
{
if (!$this->_response) {
$response = Zend_Controller_Front::getInstance()->getResponse();
if ($response) {
$this->setResponse($response);
}
}
if (!$this->_response) {
require_once 'Zend/Wildfire/Exception.php';
throw new Zend_Wildfire_Exception('Response objects not initialized.');
}
return $this->_response;
}
}