How to i add a cache id into Full Page Cache

Question

i have a categories menu, when i add a new category to it even after i reindex and refresh every cache it doesn't update even though the top navigation has and i can navigate to it via url, it only appears after i flush the cache storage

i get it from the cache using this line of code

Mage::app()->getCache()->load($this->getCacheId());

$this->getCacheId() just returns the string LEFTCATEGORIES

now even if i disable all the caches it still remains until i either flush the storage cache or delete the cache folder (and even the full page cache folder if it's enabled)

now it's not very often that new categories are added into magento but we don't really want to have to flush the storage cache every time we create a new category

so how do i add my LEFTCATEGORIES cache id to the full page cache so that when we refresh it it gets refreshed as well

Answer 1

figured it out, my LEFTCATEGORIES cache didn't have any tags when i saved it, so when i did Mage::app()->getCache()->save($output, $this->getCacheId()); i just needed to add , array("FPC") to add it to the full page cache so it now refreshes, i just had to clear the cache storage again to get the new cache and now when i make a change and refresh the full page cache it updates aswell