don't immediately reply to the request, wait a random time [0, MX]

before repling as per draft-goland-http-udp-04.txt

[git-p4: depot-paths = "//depot/": change = 720]

SSDP.py

@@ -7,10 +7,12 @@
 # Implementation of SSDP server under Twisted Python.
 #
 
+import random
 import string
 
 from twisted.python import log
 from twisted.internet.protocol import DatagramProtocol
+from twisted.internet import reactor
 
 # TODO: Is there a better way of hooking the SSDPServer into a reactor
 # without having to know the default SSDP port and multicast address?
@@ -45,7 +47,7 @@ class SSDPServer(DatagramProtocol):
 	lines = map(lambda x: x.replace(': ', ':', 1), lines[1:])
         lines = filter(lambda x: len(x) > 0, lines)
 
-	headers = [string.split(x, ':', 1) for x in lines[1:]]
+	headers = [string.split(x, ':', 1) for x in lines]
         headers = dict(map(lambda x: (x[0].lower(), x[1]), headers))
 
         if cmd[0] == 'M-SEARCH' and cmd[1] == '*':
@@ -82,11 +84,12 @@ class SSDPServer(DatagramProtocol):
         for k, v in self.known[headers['st']].items():
             response.append('%s: %s' % (k, v))
 
-        log.msg('responding with: %s' % response)
+	delay = random.randint(0, int(headers['mx']))
+        log.msg('responding in %d with: %s' % (delay, response))
 
 	# TODO: we should wait random(headers['mx'])
-        self.transport.write(
-            string.join(response, '\r\n') + '\r\n\r\n', (host, port))
+	reactor.callLater(delay, self.transport.write,
+	    string.join(response, '\r\n') + '\r\n\r\n', (host, port))
 
     def register(self, usn, st, location):
         """Register a service or device that this SSDP server will