Question

Let’s have a simple xmlrpc server defined as in the following code:

from SimpleXMLRPCServer import SimpleXMLRPCServer

def add(x,y):
    return x+y

server = SimpleXMLRPCServer(("localhost", 8000))
server.register_function(add, 'addthem')
server.register_function(add, 'add.numbers')
server.register_function(add, 'sum.two.numbers')
server.serve_forever()

which you can connect to via

import xmlrpclib
dev = xmlrpclib.ServerProxy("http://localhost:8000/RPC2")

With the dev object, you cann access the (for reasons of simplicity same) function add in the server, like

print dev.addthem(1,2)
print dev.add.numbers(1,2)
print dev.sum.two.numbers(1,2)

My question: What are the pieces of those calls? What is dev (I suppose an instance of xmlrpclib.ServerProxy), what is sum in dev.sum (a function? a callable? a class? an instance?). What is two in dev.sum.two …

For example, the following syntax

print dev.add

results in an error

xmlrpclib.Fault: <Fault 1: '<type \'exceptions.Exception\'>:method "add.__str__" is not supported'>

Shouldn’t that print something always? What is dev.add and the other pieces?

Answer 1

In order to “log” requests, you could (for example) implements a custom Transport in your client.

From the doc (adapted):

import xmlrpclib, httplib, gzip

class LogTransport(xmlrpclib.Transport):
    def send_request(self, connection, handler, request_body):
        # log here.
        print handler, request_body
        if (self.accept_gzip_encoding and gzip):
            connection.putrequest("POST", handler, skip_accept_encoding=True)
            connection.putheader("Accept-Encoding", "gzip")
        else:
            connection.putrequest("POST", handler)

p = LogTransport()
server = xmlrpclib.Server('http://time.xmlrpc.com/RPC2', transport=p)
print server.currentTime.getCurrentTime()

Output:

/RPC2 <?xml version='1.0'?>
<methodCall>
<methodName>currentTime.getCurrentTime</methodName>
<params>
</params>
</methodCall>

and a server error (because it doesn’t exists)