The filter architecture periodically gets discussed here, and I've been meaning to write up my thoughts for some time. I'm using a module that implements a slightly different filter API, primarily for filtering in a proxy context.
I've now written a brief discussion document on the subject. It's mostly an abstraction of what I'm currently using, although it does propose some additional improvements, primarily with regard to protocol handling (reflecting the recent byteranges thread here). It generated an interesting discussion, including some interesting alternative ideas, last night on IRC. Perhaps it can lead to a general-purpose module for 2.0 and an architecture update for 2.2? http://www.apachetutor.org/dev/smart-filter -- Nick Kew
