simple_server.py

""" WebSocket test resource.

This code will run a websocket resource on 8080 and reachable at ws://localhost:8080/test.
For compatibility with web-socket-js (a fallback to Flash for browsers that do not yet support
WebSockets) a policy server will also start on port 843.
See: http://github.com/gimite/web-socket-js
"""

__author__ = 'Reza Lotun'


from datetime import datetime

from twisted.internet.protocol import Protocol, Factory
from twisted.web import resource
from twisted.web.static import File
from twisted.internet import task

from websocket import WebSocketHandler, WebSocketSite, WebSocketWrapperFactory

class Echo(Protocol):
    def dataReceived(self, data):
        print "Received data '%s'" % data.strip()
        self.transport.write(data)

class EchoFactory(Factory):
    protocol = Echo

class Testhandler(WebSocketHandler):
    def __init__(self, transport):
        WebSocketHandler.__init__(self, transport)
        self.periodic_call = task.LoopingCall(self.send_time)

    def __del__(self):
        print 'Deleting handler'

    def send_time(self):
        # send current time as an ISO8601 string
        data = datetime.utcnow().isoformat().encode('utf8')
        self.transport.write(data)

    def frameReceived(self, frame):
        print 'Peer: ', self.transport.getPeer()
        self.transport.write(frame)
        self.periodic_call.start(0.5)

    def connectionMade(self):
        print 'Connected to client.'
        # here would be a good place to register this specific handler
        # in a dictionary mapping some client identifier (like IPs) against
        # self (this handler object)

    def connectionLost(self, reason):
        print 'Lost connection.'
        self.periodic_call.stop()
        del self.periodic_call
        # here is a good place to deregister this handler object


class FlashSocketPolicy(Protocol):
    """ A simple Flash socket policy server.
    See: http://www.adobe.com/devnet/flashplayer/articles/socket_policy_files.html
    """
    def connectionMade(self):
        policy = '<?xml version="1.0"?><!DOCTYPE cross-domain-policy SYSTEM ' \
                 '"http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">' \
                 '<cross-domain-policy><allow-access-from domain="*" to-ports="*" /></cross-domain-policy>'
        self.transport.write(policy)
        self.transport.loseConnection()



if __name__ == "__main__":
    from twisted.internet import reactor

    # run our websocket server
    # serve index.html from the local directory
    root = File('.')
    site = WebSocketSite(root)

    # test handler
    site.addHandler('/test', Testhandler)

    # example of wrapping a factory in order to provide WebSockets transport
    echo_factory_wrapped = WebSocketWrapperFactory(EchoFactory())
    site.addHandler('/echo', echo_factory_wrapped.buildHandler)

    reactor.listenTCP(8080, site)
    # run policy file server
    #factory = Factory()
    #factory.protocol = FlashSocketPolicy
    #reactor.listenTCP(843, factory)
    reactor.run()