/**
* 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);
}
}
Dry Cake Discharge - Sparkler Filters, Inc. - Liquid Filtration
The Sparkler ® MCRO (DCD) Filter is cleaned with speed and efficiency by means of a pneumatic vibrator, but can also be cleaned manually. After the filtration cycle is finished, the filter cake is dried on the filter plates using air or gas and the tank is opened. The pneumatic vibrator is actuated and the vibrations are transmitted through the vibrator bar which is mounted alongside of the filter plate bundle. The filter plates are vibrated and the cake falls off in pieces. Since the plates have a vibrator connection on the side, the top side shakes and the bottom side shakes. The vibrator should be operated for a minute at a time. Vibrator operation continues until cake is discharged.
The above picture shows a MCRO-DCD Filter which has dual vibrators, a sectional outlet manifold, and a quick opening closure