python implementation of unity socket policy server

SocketSecurityServer

#!/usr/bin/python

#description:python implementation of sockpol.cs for Unity corss domain socket security policy.
#last-modified:2012/4/9 14:03
#author:huliangjie

import socket
import select
import threading
import time

PACKET_SIZE = 512

try:
  policy_file = open("policy.xml")
	FULL_POLICY = ""
	for line in policy_file:
		FULL_POLICY += line
	policy_file.close()
	print("read policy from policy.xml")
except:
	print("no policy file")
	FULL_POLICY = "<?xml version='1.0'?><cross-domain-policy><allow-access-from domain='*' to-ports='*' /></cross-domain-policy>";
POLICY_DATA = FULL_POLICY.encode('ascii')
print(POLICY_DATA)

class SocketSecurityServer:

	def __init__( self, port ):
		self.port = port
		self.srvsock = socket.socket( socket.AF_INET, socket.SOCK_STREAM )
		self.srvsock.setsockopt( socket.SOL_SOCKET, socket.SO_REUSEADDR, 1 )
		self.srvsock.bind( ("", port) )
		self.srvsock.listen( 2000 )
		self.descriptors = [self.srvsock]
		#threading.Thread(target=self.periodMessage).start()
		print("SocketSecurityServer started on port %d" % port)
		
	#def periodMessage(self):
	#	while True:
	#		time.sleep(2)
	#		self.broadcast_string('message from server')
		
	def run( self ):
		while 1:
			# Await an event on a readable socket descriptor
			(sread, swrite, sexc) = select.select( self.descriptors, [], [] )
			
			# Iterate through the tagged read descriptors
			for sock in sread:
				# Received a connect to the server (listening) socket
				if sock == self.srvsock:
					self.accept_new_connection()
				else:
					# Received something on a client socket
					try:
						str = sock.recv(PACKET_SIZE)
					except socket.error:
						print("connection halt")
						str = ''
						
					# Check to see if the peer socket closed
					if str == '':
						host,port = sock.getpeername()
						str = 'connection lost %s:%s' % (host, port)
						#self.broadcast_string( str, sock )
						sock.close
						self.descriptors.remove(sock)
					else:
						if str == b"<policy-file-request/>\x00":
							self.send_policy(sock)
						else:
							print("invalid connection %s:%s" % sock.getpeername())
						sock.close
						self.descriptors.remove(sock)
						#newstr = '[%s:%s] %s' % (host, port, str)
						#self.broadcast_string( newstr, sock )

	def accept_new_connection( self ):
		newsock, (remhost, remport) = self.srvsock.accept()
		#newsock.send("You're connected to the Python chatserver")
		#str = 'Client joined %s:%s' % (remhost, remport)
		#self.broadcast_string( str )
		self.descriptors.append( newsock )
		
	def send_policy(self, sock):
		try:
			sock.send(POLICY_DATA)
			print('policy sent to %s:%s' % sock.getpeername())
		except socket.error:
			print('can not send policy. socket error.')
	
	def broadcast_string( self, str, omit_sock=None ):
		for sock in self.descriptors:
			if sock != self.srvsock and sock != omit_sock:
				#~ print sock.getpeername()
				sock.send(str)

if __name__ == "__main__":
	myServer = SocketSecurityServer(843).run()