I want to create a module that will hook events for images being added to products or vendors etc so that when it's saved and was already an existing image (image was being updated) - that it would invalidate that image (in cloudfront).
What events would allow me to detect this; maybe extend the image.php where it saves the image? Currently I don't see any dispatched events that will help me;
Mage::dispatchEvent('catalog_product_media_add_image', array('product' => $product, 'image' => $file));
But found that the event is not dispatched when adding an image to a product. But technically - I only need to know about changed images - is there a way for me to detect (by hooking the before or after product save event) what properties have been updated?
Any direction would be greatly appreciated.