Should be eminently doable with generators. Just have the filter processing be a generator "stack" that passes/and `yield up()s" a standard envelope type--you'd design this envelope and roll your own mini-filtering-framework depending on what kind of data you need wrapped.
A close analog in the Python world is WSGI, and the WSGI middleware concept. Check out PEP 333 (http://www.python.org/dev/peps/pep-0333/) for some details about how that particular pluggable/chaining/ filtering system was designed. - Jamie On Jan 3, 6:36 pm, falcon <[email protected]> wrote: > I like what I see in diesel. I am not a python programmer, so please > excuse me if the question has an obvious answer. I am looking to use > this framework to implement a text based protocol. As with most > protocols, I need to parse incoming data, dispatch it to some handler > function, maintain sessions, use heartbeats, etc., etc. Java > frameworks such as netty, mina and grizzly use a pattern called > "intercepting filters," (java servlets make light use of them as > well). The idea is simple, I break up various parts of my logic into > different pieces of code, then connect them to each other in a chain. > > For example, the "log in/out" filter tests to see if the connection is > valid, and nothing else. All subsequent filter never have to worry > about authentication, if a request gets to them, then the login/out > filter approved. > > As far as I can tell, Python's generators should make such a pattern > far easier than Java, but I don't see relevant examples in the > literature (python or diesel). > > Any pointers? > > Thanks
