The web server I use at work are multi homed with the default route being the internal management network. We came across an issue where we wanted make a XMLHTTPRequest for a data feed from another company into our web app. We all know due to cross-site scripting attacks this is no longer possible so we had to write a little proxy script to pull the data and serve it from our own site. The standard python httplib doesn’t have the ability to bind to a specific interface so I have done a little sub-classing and now have a HTTPConnection which allows me to bind to a specific interface. Hope this helps someone as from my searching it seems to be a common request. You will meed to change the IP address to match your setup :-)

import httplib
import socket



class HTTPConnectionInterfaceBound(httplib.HTTPConnection):
    """This class allows communication via a bound interface for
       multi network interface machines."""

    def __init__(self, host, port=None, strict=None, bindip=None):
        httplib.HTTPConnection.__init__(self, host, port, strict)
        self.bindip = bindip


    def connect(self):
        """Connect to the host and port specified in __init__."""
        msg = "getaddrinfo returns an empty list"
        for res in socket.getaddrinfo(self.host, self.port, 0,
                                      socket.SOCK_STREAM):
            af, socktype, proto, canonname, sa = res
            try:
                self.sock = socket.socket(af, socktype, proto)
                if self.debuglevel > 0:
                    print "connect: (%s, %s)" % (self.host, self.port)
                if self.bindip != None :
                    self.sock.bind ((self.bindip, 0))
                self.sock.connect(sa)
            except socket.error, msg:
                if self.debuglevel > 0:
                    print 'connect fail:', (self.host, self.port)
                if self.sock:
                    self.sock.close()
                self.sock = None
                continue
            break
        if not self.sock:
            raise socket.error, msg



conn = HTTPConnectionInterfaceBound('www.thegoldfish.org', 80, bindip='192.168.56.83')
conn.request("GET", "/")
r1 = conn.getresponse()
print r1.status, r1.reason
print r1.read()