I am studying the implementation of twisted UDP-related classes, and I do not understand the point of the "numPorts" attribute of AbstractDatagramProtocol.
It is clearly designed to avoid multiple calls to startProtocol() from doStart(), but I fail in imagining a scenario where this may happen since, as the comment states, doStart() should only be called by makeConnection(), which has an explicit "assert self.transport == None" guard which, indeed, prevents multiple calls. So why bother to count calls? Moreover, makeConnection() could be called multiple times on the same DatagramProtocol instance if it was "bound" to multiple ports (multiple calls to listenUDP), which can be an interesting scenario but is prevented by : - the above assertion, - the fact that AbstractDatagramProtocol.transport is not a collection, so only the last Port would be available anyway. Is my reasoning wrong or incomplete? If not, couldn't we simplify AbstractDatagramProtocol implementation by removing numPorts? Two other small remarks regarding documentation / understandability : - The note "This does not actually implement IListeningPort" on udp.Port lead me to think that IReactorUDP.listenUDP should not be declared as returning an object implementing IListeningPort in the first place (confused me!). - I had to read the code to understand that a "transport" and a "port" are exactly the same thing in the UDP implementation. The tutorial and the documentation were not clear about this point, so I did not make the link between the "self.transport" available in DatagramProtocol and the value returned by listenUDP (confused me!). Regards, Olivier. _______________________________________________ Twisted-Python mailing list Twisted-Python@twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
