Here is the solution for disabling FPC for a specific controller by listen on the controller_action_predispatch event:
public function processPreDispatch(Varien_Event_Observer $observer) { $action = $observer->getEvent()->getControllerAction(); if($action instanceof Mage_Catalog_ProductController) { $cache = Mage::app()->getCacheInstance(); $cache->banUse('full_page'); } }
Then add the following to your config.xml file for the module. This goes in the <frontend> section:
YOURMODULE/observer processPreDispatch
Now Magento will server up your page every time and bypass FPC for the request.