TwistedWebsocket 0.0.6.2

Websocket protocol implementation based on Twisted

Websocket server protocol implementation based on Twisted.

Requirements

• Python 2.7+

• Twisted

Installation

pip install TwistedWebsocket

Testing

python setup.py test

Built-in broadcast server

A server is already integrated into TwistedWebsocket package. Default listening port is 9999

python -m TwistedWebsocket.server [PORT]

API

Frame manager

• TwistedWebsocket.frame.Frame(buf): Create Frame instance

• TwistedWebsocket.frame.Frame.message(): Return decoded message from frame instance

• TwistedWebsocket.frame.Frame.length(): Return frame length from frame instance

• TwistedWebsocket.frame.Frame.buildMessage(msg, mask=True): (@staticmethod) Create a websocket compatible frame. If mask == True, it will be a client->server frame.

Server Protocol

• TwistedWebsocket.server.Protocol.onHandshake(header): Callback when HTTP-like client header is received

• TwistedWebsocket.server.Protocol.onConnect(): Callback when the client is connected

• TwistedWebsocket.server.Protocol.onDisconnect(): Callback when the client is disconnected

• TwistedWebsocket.server.Protocol.onMessage(msg): Callback when the client receive a message

• TwistedWebsocket.server.Protocol.sendMessage(msg): Send a message to the client

• TwistedWebsocket.server.Protocol.users: Dictionnary ( self == self.clients[self.id] ) off all the clients connected to the server

• TwistedWebsocket.server.Protocol.id: Client UUID4 id

Exceptions

• TwistedWebsocket.exception.FrameError

• TwistedWebsocket.exception.ProtocolError

Default Implementation

Broadcast server example:

from twisted.internet.protocol import Factory
from twisted.internet import reactor
from TwistedWebsocket.server import Protocol
import re


class WebSocketHandler(Protocol):

  def onHandshake(self, header):
    g = re.search('Origin\s*:\s*(\S+)', header)
    if not g: return
    print "\n[HANDSHAKE] %s origin : %s" % (self.id, g.group(1))

  def onConnect(self):
    print "\n[CONNEXION] %s connected" % self.id
    for _id, user in self.users.items():
      user.sendMessage("%s connected" % self.id)
      print "\n[FRAME] from %s to %s:\n%s connected" % (self.id, _id, self.id)

  def onDisconnect(self):
    print "\n[DISCONNEXION] %s disconnected" % self.id
    for _id, user in self.users.items():
      user.sendMessage("%s disconnected" % self.id)
      print "\n[FRAME] from %s to %s:\n%s disconnected" % (self.id, _id, self.id)

  def onMessage(self, msg):
    for _id, user in  self.users.items():
      user.sendMessage(msg)
      print "\n[FRAME] from %s to %s:\n%s" % (self.id, _id, msg)


class WebSocketFactory(Factory):

  def __init__(self):
    self.users = {}

  def buildProtocol(self, addr):
    return WebSocketHandler(self.users)


reactor.listenTCP(9999, WebSocketFactory())
reactor.run()

WSS support

from twisted.internet.protocol import Factory
from twisted.internet import reactor, ssl
from TwistedWebsocket.server import Protocol
import re

class WebSocketHandler(Protocol):
  ...

class WebSocketFactory(Factory):
  ...

with open("./keys/ssl.localhost.key") as keyFile:
    with open("./keys/ssl.localhost.cert") as certFile:
      cert = ssl.PrivateCertificate.loadPEM(keyFile.read() + certFile.read())

reactor.listenSSL(PORT, WebSocketFactory(), cert.options())
reactor.run()

Generate self-signed SSL certificates:

$> openssl genrsa -out ./keys/ssl.localhost.key 2048
$> openssl req -new -x509 -key ./keys/ssl.localhost.key \
   -out ./keys/ssl.localhost.cert -days 3650 -subj /CN=ssl.localhost

TODO

• Improve frame building

• Add WSS example with self-signed certificates