Forward a port via UPnP in Python

Question

I am making a Python application that requires the user to have a port forwarded to his computer in order to communicate with a server or another user. The current implementation works quite great, yet the only thing is that the person who's running the file must forward the port to the local IP manually. I want to automate this. He picks a port, script checks if it can be forwarded, then it forwards it. If it can't, it handles the error respectively.

I've looked into some libraries that claim they can do this in pure Python (since I will need to compile to .exe's [...] after finishing) but didn't manage to find something useful. If you could provide me with a code sample on how to attempt to forward a port and handle success/fail respectively, that would be great.

Thanks in advance for your time.

P.S.:It's Python 2.7.X that I am targeting

Answer 1

Looks like there are a few options:

• Miniupnp has python bindings
• Python bindings for GNUPnP
• miranda-upnp is pure python

There is a nice example of the python bindings for GNUPnP being used to open ports on a router here. In that example the lease time is set to 0, which is unlimited. See here for the definition of add_port.

A simple example might be:

#! /usr/bin/python
import gupnp.igd
import glib
from sys import stderr

my_ip = YOUR_IP

igd = gupnp.igd.Simple()
igd.external_ip = None

main = glib.MainLoop()

def mep(igd, proto, eip, erip, port, localip, lport, msg):
    if port == 80:
        igd.external_ip = eip
        main.quit()

def emp(igd, err, proto, ep, lip, lp, msg):
    print >> stderr, "ERR"
    print >> stderr, err, proto, ep, lip, lp, msg
    main.quit()

igd.connect("mapped-external-port", mep)
igd.connect("error-mapping-port", emp)

#igd.add_port("PROTO", EXTERNAL_PORT, INTERNAL_IP, INTERNAL_PORT, LEASE_DURATION_IN_SECONDS, "NAME")
igd.add_port("TCP", 80, my_ip, 8080, 86400, "web")

main.run()