Thanks for the answer! I was hoping to avoid having to put something like AMP in place, because it looked a bit overkill for my case. I think I actually found a way :-) I guess I can use the same factory to start all my servers. So I start my sniffer (in a thread) in my ServerFactory and I keep a dictionary of deferred for each line (corresponds to an emitter and a server port). It allows me to call the messageToSend method corresponding to the proper server when receiving data. Here is a code extract of what I implemented: class Oldimon(Protocol): def __init__(self, factory): self.factory = factory self.line = None def connectionMade(self): # Check the server port to get the line # associated to this protocol port = self.transport.getHost().port self.line = LINES_PORT[port] # Add the callback for this line self.factory.deferred[self.line] = defer.Deferred() self.factory.deferred[self.line].addCallback(self.messageToSend) class OldimonFactory(ServerFactory): def __init__(self, device, pcap_filter): # pcapDataReceived callback is called everytime a message # is received reactor.callInThread(run_pcap, device, pcap_filter, self.pcapDataReceived) # Dict with a deferred for each line self.deferred = dict(zip(LINES_PORT.values(), [None] * len(LINES_PORT))) def buildProtocol(self, addr): return Oldimon(self) def pcapDataReceived(self, data, line): if self.deferred[line] is not None: # Fire the callback for line d, self.deferred[line] = self.deferred[line], None d.callback(data) oldimon_factory = OldimonFactory(device, pcap_filter) for port in LINES_PORT.keys(): reactor.listenTCP(port, oldimon_factory) reactor.run() Le 1 mars 2013 à 15:31, Laurens Van Houtven <_@lvh.cc> a écrit :
Well, you'd presumably have a connection to each of the servers in the form of a client factory and a protocol instance. Then, every time you get a message, you figure out which protocol instance you want (the one for the appropriate server) and send a message to it. You could do that with self.transport.write, of course, but it would be much easier to just use a ready-made RPC thing.
One such RPC thing is AMP, which comes with Twisted. You can read more about it here:
http://amp-protocol.net/ https://twistedmatrix.com/documents/current/core/howto/amp.html
You will probably end up having a command like HandlePacket or something (presumably you can come up with a more apt domain-specific name), and something close to self.servers[serverFor(packet.origin)].callRemote(HandlePacket, packet.data), or whatever.
I realize this is still pretty vague and high level, so feel free to ask more questions about the parts that are unclear :)
On Thu, Feb 28, 2013 at 10:59 PM, Benjamin BERTRAND <beenje@gmail.com> wrote: Hi,
I have to replace a piece of software that sniffs the traffic on one interface. It gets different messages that are each associated to a specific emitter. On the same machine, one server is started for each emitter (on a different port). And the application is just supposed to use the proper server to send the messages captured (to a client on another machine).
Not sure if it's clear, but basically if I have 2 emitters A and B, I'll start 2 servers (a and b). My sniffer will get messages A1, A2, B1, B2, B3... I have to pass messages A1, A2 to server a, that will just send them to the client (if it is connected of course). And B1, B2, B3 to server b. I don't need any buffering. If no client is connected, messages captured are just discarded.
To sniff the network, I want to use pylibpcap or pcapy. I found this example to make it work with twisted: http://dound.com/2009/09/integrating-twisted-with-a-pcap-based-python-packet...
Starting several servers that use the same protocol is not a problem. But how do I pass the messages captured to the right server? How do I make the link between the function sniffing the network and the servers?
Thanks
Benjamin _______________________________________________ Twisted-Python mailing list Twisted-Python@twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python
-- cheers lvh _______________________________________________ Twisted-Python mailing list Twisted-Python@twistedmatrix.com http://twistedmatrix.com/cgi-bin/mailman/listinfo/twisted-python