/**
* Siteground Joomla Cache Plugin
*
* Flushes varnish cache when certain data change actions are invoked. Disables varnish cache
* on SiteGround servers when users are logged in.
*
* @author George Penkov
* @category Siteground Joomla Plugins
* @package Siteground Joomla Cache Plugin
*/
defined('_JEXEC') or die();
JLoader::import('joomla.plugin.plugin');
JLoader::import('joomla.error.log');
/**
* jSGCache Plugin
*
* @package jSGCache
* @subpackage System
*/
class plgSystemjSGCache extends JPlugin
{
/**
* JRegistry parameter object for the plugin.
* @var JRegistry
*/
public $params = null;
/**
* Web path to the joomla application.
* @var string
*/
private $_applicationPath = null;
/**
* Global cache flag.
* @var bool
*/
private $_cacheEnabled = false;
/**
* Auto flush flag
* @var bool
*/
private $_autoflush = false;
/**
* 3rd party auto flush flag
* @var bool
*/
private $_autoflush3rdParty = false;
/**
* Client side auto flush flag
* @var bool
*/
private $_autoflushClientSide = false;
/**
* Which tasks to ignore in the flush monitor
* @var array
*/
private static $_ignoreTasks = array('login','logout','user.login','user.logout');
/**
* Constructor
*
* @access public
* @param object &$subject The object to observe
*/
public function __construct( &$subject )
{
if(isset($_GET['sgCacheCheck']) && $_GET['sgCacheCheck'] == md5('joomlaCheck'))
die('OK');
parent::__construct( $subject );
$plugin = JPluginHelper::getPlugin('system','jSGCache');
$this->params= new JRegistry();
$this->params->loadString($plugin->params, 'JSON');
$this->_cacheEnabled = $this->params->get('cache_enabled');
if ($this->_cacheEnabled === null)
$this->_cacheEnabled == 1;
$this->_autoflush = $this->params->get('autoFlush');
if ($this->_autoflush === null)
$this->_autoflush = 1;
$this->_autoflush3rdParty = $this->params->get('autoFlush-ThirdParty');
if ($this->_autoflush3rdParty === null)
$this->_autoflush3rdParty = 1;
$this->_autoflushClientSide = $this->params->get('autoFlush-ClientSide');
if ($this->_autoflushClientSide === null)
$this->_autoflushClientSide = 0;
}
/**
* Heartbeat cache checking function. Will also monitor $_GET for the jSGCache parameter
* (pressing the purge cache button in admin)
*
*
* @access public
* @return null
*/
public function onAfterInitialise()
{
if (!$this->_cacheEnabled || $this->_isBlacklisted($this->_applicationPath))
{
JResponse::setHeader('X-Cache-Enabled','False',true);
return;
}
if ($this->_cacheEnabled)
{
JResponse::setHeader('X-Cache-Enabled','True',true);
}
//Init the application url
$this->_applicationPath = str_replace(array('administrator/index.php','index.php'),'',str_replace($_SERVER['DOCUMENT_ROOT'],'',$_SERVER['SCRIPT_FILENAME']));
//Check for any admin action and proceed to flushMonitor and 3rd party plugins
if ( isset($_POST['task']) || isset($_GET['task']) || isset($_GET['cart_virtuemart_product_id']))
{
$this->_flushMonitor();
if ($this->_autoflush3rdParty)
$this->_monitorThirdPartyPlugins();
}
//Check if we have a logged in user and enable cache bypass cookie 'task' => string 'user.login'
$user = JFactory::getUser();
if (!$user->guest || (isset($_POST['task']) && preg_match('/login/i', $_POST['task'])))
{
$_POST[JSession::getFormToken()] = 1; //Force the correct token, since the login box on the page is cached with the 1st visitors' token
//Enable the cache bypass for logged users by setting a cache bypass cookie
setcookie('jSGCacheBypass',1,time() + 6000,'/');
}
if ($user->guest || (isset($_POST['task']) && $_POST['task'] == 'user.logout'))
{
//Remove the bypass cookie if not a logged user
if (isset($_COOKIE['jSGCacheBypass']))
setcookie('jSGCacheBypass',0, time() - 3600,'/');
}
// Handle purge button press when get has jSGCache=purge, but only in admin with a logged user
if(isset($_GET['jSGCache']) && $_GET['jSGCache'] == 'purge' && JFactory::getApplication()->isAdmin() && !$user->guest )
$this->_purgeCache(true);
}
/**
* Admin panel icon display
*
* @access public
* @param string $context
* @return array
*/
public function onGetIcons( $context )
{
return array(array(
'link'=>'?jSGCache=purge',
'image'=>'header/icon-48-purge.png',
'text'=>JText::_('Purge jSGCache'),
'id'=>'jSGCache'
));
}
/**
* Calls the cache server to purge the cache
*
* @access public
* @param string|bool $message Message to be displayed if purge is successful. If this param is false no output would be done
* @return null
*/
private function _purgeCache( $message = true )
{
$purgeRequest = $this->_applicationPath . '(.*)';
// Check if caching server is varnish or nginx.
$sgcache_ip = '/etc/sgcache_ip';
$hostname = $_SERVER['SERVER_ADDR'];
$purge_method = "PURGE";
if (file_exists($sgcache_ip)) {
$hostname = trim( file_get_contents( $sgcache_ip, true ) );
$purge_method = "BAN";
}
$cacheServerSocket = fsockopen($hostname, 80, $errno, $errstr, 2);
if(!$cacheServerSocket)
{
JError::raise(E_ERROR,500,JText::_('Connection to cache server failed!'));
JError::raise(E_ERROR,500,JText::_($errstr ($errno)));
return;
}
$request = "$purge_method {$purgeRequest} HTTP/1.0\r\nHost: {$_SERVER['SERVER_NAME']}\r\nConnection: Close\r\n\r\n";
if (preg_match('/^www\./',$_SERVER['SERVER_NAME']))
{
$domain_no_www = preg_replace('/^www\./', '', $_SERVER['SERVER_NAME']);
$request2 = "$purge_method {$purgeRequest} HTTP/1.0\r\nHost: {$domain_no_www}\r\nConnection: Close\r\n\r\n";
}
else
$request2 = "$purge_method {$purgeRequest} HTTP/1.0\r\nHost: www.{$_SERVER['SERVER_NAME']}\r\nConnection: Close\r\n\r\n";
fwrite($cacheServerSocket, $request);
$response = fgets($cacheServerSocket);
fclose($cacheServerSocket);
$cacheServerSocket = fsockopen($hostname, 80, $errno, $errstr, 2);
fwrite($cacheServerSocket, $request2);
fclose($cacheServerSocket);
if($message !== false)
{
if(preg_match('/200/',$response))
{
if ($message === true)
JFactory::getApplication()->enqueueMessage(JText::_('SG Cache Successfully Purged!'));
else
JFactory::getApplication()->enqueueMessage(JText::_( $message ));
}
else
{
JError::raise(E_NOTICE,501, JText::_('SG Cache: Purge was not successful!'));
JError::raise(E_NOTICE,501, jText::_('Error: ' . $response));
}
}
}
/**
* Check if url is in caching blacklist
*
* @param string $applicationPath
*
* @return bool
*/
private function _isBlacklisted($applicationPath)
{
$blacklistArray = explode("\n",$this->params->get('blacklist'));
$blacklistRegexArray = array();
$indexIsBlacklisted = false;
foreach($blacklistArray as $key=>$row)
{
$row = trim($row);
if ($row != '/' && $quoted = preg_quote($row,'/'))
$blacklistRegexArray[$key] = $quoted;
if ($row == '/')
$indexIsBlacklisted = true;
}
if ($indexIsBlacklisted && $_SERVER['REQUEST_URI'] == $applicationPath)
return true;
if (empty($blacklistRegexArray))
return false;
$blacklistRegex = '/('.implode('|',$blacklistRegexArray) . ')/i';
return preg_match($blacklistRegex, $_SERVER['REQUEST_URI']);
}
/**
* 3rd party plugin monitor
*
* @access private
* @return null
*/
private function _monitorThirdPartyPlugins()
{
// Kunena & K2
if ($this->params->get('autoFlush-ThirdParty') == 1 && isset($_POST['option']) &&
($_POST['option']=='com_k2' || $_POST['option' ]== 'com_kunena'))
{
$this->_purgeCache(false);
}
// VirtueMart
if ( (isset($_POST['option']) && $_POST['option'] == 'com_virtuemart') ||
( isset($_GET['option']) && $_GET['option'] == 'com_virtuemart' ) ||
isset($_GET['cart_virtuemart_product_id']) )
{
if($this->params->get('autoFlush-ThirdParty') == 1)
$this->_purgeCache(false);
}
}
/**
* Action monitor
*
* @access private
* @return null
*/
private function _flushMonitor()
{
$user = JFactory::getUser();
if ((!JFactory::getApplication()->isAdmin() && !$this->_autoflushClientSide) || $user->guest)
return;
$autoflush = $this->params->get('autoFlush');
if ($autoflush === null)
$autoflush = 1;
if (isset($_POST['task']) && $_POST['task'] && !in_array($_POST['task'],self::$_ignoreTasks) && $autoflush == 1)
$this->_purgeCache(false);
}
}
Vertical Filter - Sparkler Filters, Inc. - Liquid Filtration
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