On Thu, 2007-09-20 at 22:19 +0200, Stefan Arentz wrote:

I need to let Objective-C (OS X / Cocoa) clients speak to a Twisted server. The protocol needs to be a pretty simple request/response style protocol on a persistent TCP connection. Possible over SSL.

Before I start inventing a wheel, does anyone know if there is something simple available already? Would the Perspective Broker be a good start? I haven't looked at the internals but maybe it is not too difficult to create a non-python client for it?

This is sort of an FAQ. The PB wire protocol assumes full asynchronous and symmetry; either side of the connection can issue any callRemote at any time. The responses may take milliseconds, minutes or days to come back. Effectively, the PB wire protocol *is* deferreds. If your client-side environment can support that, then it'll work. If (as seems likely) it can't, then it won't. If you only need simple RPC-like semantics (no callbacks from server to client) with simple objects (strings, ints, list, dicts) XMLRPC is an option. Or, you could run a Twisted reactor in a thread on the client side, and call from the main/gui thread into Twisted, let it do the PB and call you back when it's done. Or you could write the client in Python ;o)