This extension will help in getting better performances out of eZ publish by making cache-blocks clearing much more efficient.

More efficient ?

While ViewCaching is very powerful and can be customized heavily thanks to SmartCacheClear, cache-blocks clearing is quite... basic. The only available parameter is subtree_expiry, that lets you define a subtree that will trigger cache clearing for this block. Navigations menu being one of the main uses of this feature, we end up with a nasty situation: to get your menu to update when new content is published, you have to set it's subtree expiry to the root of your contents. Usually, the content's root contains items that are not displayed in the menu. Publishing them should not affect this cache-block.

What the extension does

This is where eZ cache-block expirer helps. It lets you define a subtree (or a list of subtrees), as well as list of content classes that affects your cache-block. When an object that is an instance of one of these classes and belongs to one of the subtrees is published, the cache-block is cleared. If an item of these subtrees is published and is not an instance of one of the classes, the cache-block is not cleared.

Is it documented

Haha, good one. This first version is not really documented, but a specifications document can be found in doc/specs.txt. It should help you get started.

What's next ?

I didn't have much time to spend on this extension right now, but the idea had been around for a while. The next major step is the implementation of the second major feature of the extension: administration from the backoffice. How ? The extension relies on a content object that is used to clear a cache-block. The idea is to create a datatype that will replace the current INI configuration. In this datatype, one will be able to add subtrees and select content classes that affect the current object.