hook_expire_cache passes <front>: Feature or bug?

I pass along a fully qualified URL as that has all the info one needs; if I pass along less info then something might be missing. I see that you are already using parse_url() in your code. This is the correct way to extract what you need.

Another reason I pass full URL's is so an external crawler can be used for expiration (hit the url to refresh the cache) instead of a hard flush like varnish does. At work we use boost because of the boost_cache database table. It works with views and panels. We have a crawler (not written in php) that checks for urls that need to be re-crawled every 30 seconds. By going this route we almost always have every page in our varnish cache & we support a cache lifetime of 10 days.

I'm keeping the Cache Expiration module very light but I plan on supporting more cache expiration features from boost once I get the performance and memory usage under control when using views and panels expiration. To see what I'm talking about give the latest dev version of boost a try; I find it works very well in terms of detecting what pages a node shows up on (node create/update) or used to show up on (node deletion).

EDIT:
helps to read the title. <front> shouldn't be passed along; it should be the actual URL.

committed