Chaz. wrote:
radix@twistedmatrix.com wrote:
On 03:49 pm, eprparadocs@gmail.com wrote:
I have a XMLPRC client that works well under TCP and I am now trying to get it to work under Multicast conditions.
It is unlikely that you will be able to get the XMLRPC protocol to work over multicast, given that multicast is an unreliable transport, like UDP. HTTP and XMLRPC don't know how to deal with that.
Here is the "TCP" code I used:
class StorageService(internet.TCPServer): def __init__(self,tcpPort,configInfo): r = StoragePeer(configInfo) xmlrpc.addIntrospection(r) internet.TCPServer.__init__(self,tcpPort,server.Site(r))
Subclassing the thinks in twisted.application.internet is not really how those classes are meant to be used. Why did you do this instead of just instantiating a TCPServer with the appropriate port and factory?
I changed the call to TCPServer to:
class StorageService(internet.TCPServer): def __init__(self,tcpPort,configInfo): r = StoragePeer(configInfo) xmlrpc.addIntrospection(r) internet.MulticastServer.__init__(self,tcpPort,server.Site(r))
I thought this would work since, but it doesn't. What I get returned is the following error message:
Failed to load application: unbound method __init__() must be called with MulticastServer instance as first argument (got StorageService instance instead)
This is a trivial error in your Python. You can't call methods of classes directly unless the first argument is an instance of that class.
I know how much work I will need to do to get any UDP-like protocol to work with EXACTLY-ONCE semantics.
It seems my one problem was that in the definition of my class... class StorageService(internet.TCPServer) I should have used class StorageService(internet.MulticastServer) That solved my immediate problem, though I did find out that XMLRPC does in fact assume that you have a connection oriented protocol underneath it. Now I will just have to fix that problem. Also for those of you that said you can't do: internet.TCPServer.__init__(self,...) I would suggest you are wrong. In fact that is exactly how subclassing works in Python. But that is for another time. Once again thanks! Chaz.