ssdp_upnp

Introduction

The acticle Exploring UPnP with Python gives a realy good insight of UPNP. SSDP is one of it's implementation.

The packege includes three individual Classes, ssdp server, ssdp client, nat upnp class. They first two class inherits from Class threading.Thread class, thus the two class instance runs on a single thread of own. They will not block main thread. After the ssdp client find a peer with same product name, it can communicate with main thread by queue. Nat upnp class is running on main thread, thus it will not block I/O, it will just search for LAN GDI (router with upnp nap forwarding function), and bind internal port with external port.

The logic of server is just listen a broadcast address with port 1900. If it received a "M-SEARCH" message, it will responce it's service infomation. The client just send a broadcast message with "M-SEARCH", and get server's service infomation.

The package can be used in blockchain solution where peers to find each other in LAN environment.

API

Server Class

run(): run the server in main thread with I/O blocking
start(): run the server in other thread with I/O nonblocking
stop(): stop the server

Client

run(): run the client in main thread with I/O blocking
start(): run the client in other thread with I/O nonblocking
stop(): stop the client

Nat

addPortForward(internal_port, external_port): run the function in main thread. It returns None if fail to bind, returns a tuple (external_ip, external_port) if succeed.
removePortForward(external_port): run the function in main thread. It returns True if succeed, and returns False if failed.

example

pip install ssdp-upnp

    import sys
    from ssdp_upnp.ssdp import Server, Client, Nat
    from ssdp_upnp.ssdp import gen_logger
    from queue import Queue

    logger = gen_logger('sample')

    if __name__ == '__main__':
        try:
            if sys.argv[1] == 'server':
                upnpServer  = Server(8048, 'blockchain', 'main')
                upnpServer.start()
            elif sys.argv[1] == 'client':
                queue = Queue()
                upnpClient = Client('blockchain', 'main', queue)
                upnpClient.start()
                logger.info(queue.get())
            elif sys.argv[1] == 'nat':
                nat = Nat()
                print(nat.addPortForward(8011, 8015))
            else:
                logger.warning('need params server or clinet')
        except Exception as e:
            logger.error(e)