[Twisted-Python] Dynamic listening to UDP ports?

[Jp Calderone]

On Tue, 26 Apr 2005 18:27:05 +0200, Torbjörn Einarsson <torbjorn at einarssons.se> wrote:
>Hi,
>
>
>
>I’m trying to make a server that listens to one TCP socket for commands and
>then starts listening to more or less UDP sockets for data depending on the
>commands. The UDP data shall then be forwarded to one or more outgoing UDP
>ports.
>
>For example, here are some commands with explanations:
>
>addChannel 10000                             should make the server
>listening to UDP port 10000
>
>addChannel 10002                             should make the server
>listening to UDP port 10002
>
>addConnection 10000 10.0.0.2:5000    start forwarding the packet from UDP
>port 10000 to port 5000 on another machine
>
>addConnection 10000 10.0.0.3:5002    start forwarding the packet from UDP
>port 10000 to port 5002 on yet another machine
>
>delConnection  10000 10.0.0.2:5000    stop forwarding packets to the first
>guy
>
>delConnection  10000 10.0.0.3:5002    stop forwarding packets to the second
>guy
>
>delChannel      10000                         stop listening to port 10000
>
>
>
>I’ve been making some rather advanced servers in twisted, but with fixed
>ports. How can I deal with this type of dynamic port bindings?
>
>For adding a port to listen to: reactor.listenUDP(10000,prot) is working,
>but how do I stop listening to a port an unbind it? I’ve found something
>called unlistenUDP but it seems to be deprecated?

  listenUDP returns a udp.Port.  Call stopListening() on that Port and it will shut down.

>
>Alternatively, I could start up a service , like
>
>u = internet.services.UDPServer(10000,UdpProtocol())
>
>but how do I stop this particular service without stopping all others?
>

  Just call stopService() on it.  How you arrange to know which services should have this called on them and how you track your services depends on your specific application.

  Jp