How to implement SSDP / UPnP? Trying to use Sony's camera API

Question

I'm a total beginner to HTTP requests, but I'd like to write a Python app that uses Sony's API for controlling its Wi-Fi cameras. For now, I'm just trying to talk to the camera at all, but my get request keeps failing. I have all the docs (the UPnP documentation, SSDP doc, user's manual, etc.) but I think I'm missing something really fundamental. According to Sony's doc, I need to:

1. Connect to the camera as an access point (i.e., log in like any other Wi-Fi router)
2. Send a request to a certain URL and port

Does anyone have any idea what might be going wrong here? Any good resources on getting started with UPnP / SSDP? I got the formatting for the DISCOVERY_MSG string from here.

#!/usr/bin/python

def main():
    import requests

    DISCOVERY_MSG = ('M-SEARCH * HTTP/1.1\r\n' +
                 'HOST: 239.255.255.250:1900\r\n' +
                 'MAN: "ssdp:discover"\r\n' +
                 'MX: 3\r\n' +
                 'ST: urn:schemas-sony-com:service:ScalarWebAPI:1\r\n' +
                 'USER-AGENT: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_5) AppleWebKit/536.30.1 (KHTML, like Gecko) Version/6.0.5 Safari/536.30.1\r\n\r\n')

    try:
        r = requests.get(DISCOVERY_MSG)
    except:
        print('Didn\'t work')


if __name__ == '__main__':
  main()

Answer 1

import sys
import socket

SSDP_ADDR = "239.255.255.250";
SSDP_PORT = 1900;
SSDP_MX = 1;
SSDP_ST = "urn:schemas-sony-com:service:ScalarWebAPI:1";

ssdpRequest = "M-SEARCH * HTTP/1.1\r\n" + \
                "HOST: %s:%d\r\n" % (SSDP_ADDR, SSDP_PORT) + \
                "MAN: \"ssdp:discover\"\r\n" + \
                "MX: %d\r\n" % (SSDP_MX, ) + \
                "ST: %s\r\n" % (SSDP_ST, ) + "\r\n";

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.sendto(ssdpRequest, (SSDP_ADDR, SSDP_PORT))
print sock.recv(1000)

https://github.com/crquan/work-on-sony-apis/blob/master/search-nex.py