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@vanous
Forked from jkp/websocketserver.py
Created February 10, 2016 07:43
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A simple WebSockets server with no dependencies
import struct
import SocketServer
from base64 import b64encode
from hashlib import sha1
from mimetools import Message
from StringIO import StringIO
class WebSocketsHandler(SocketServer.StreamRequestHandler):
magic = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
def setup(self):
SocketServer.StreamRequestHandler.setup(self)
print "connection established", self.client_address
self.handshake_done = False
def handle(self):
while True:
if not self.handshake_done:
self.handshake()
else:
self.read_next_message()
def read_next_message(self):
length = ord(self.rfile.read(2)[1]) & 127
if length == 126:
length = struct.unpack(">H", self.rfile.read(2))[0]
elif length == 127:
length = struct.unpack(">Q", self.rfile.read(8))[0]
masks = [ord(byte) for byte in self.rfile.read(4)]
decoded = ""
for char in self.rfile.read(length):
decoded += chr(ord(char) ^ masks[len(decoded) % 4])
self.on_message(decoded)
def send_message(self, message):
self.request.send(chr(129))
length = len(message)
if length <= 125:
self.request.send(chr(length))
elif length >= 126 and length <= 65535:
self.request.send(126)
self.request.send(struct.pack(">H", length))
else:
self.request.send(127)
self.request.send(struct.pack(">Q", length))
self.request.send(message)
def handshake(self):
data = self.request.recv(1024).strip()
headers = Message(StringIO(data.split('\r\n', 1)[1]))
if headers.get("Upgrade", None) != "websocket":
return
print 'Handshaking...'
key = headers['Sec-WebSocket-Key']
digest = b64encode(sha1(key + self.magic).hexdigest().decode('hex'))
response = 'HTTP/1.1 101 Switching Protocols\r\n'
response += 'Upgrade: websocket\r\n'
response += 'Connection: Upgrade\r\n'
response += 'Sec-WebSocket-Accept: %s\r\n\r\n' % digest
self.handshake_done = self.request.send(response)
def on_message(self, message):
print messsage
if __name__ == "__main__":
server = SocketServer.TCPServer(
("localhost", 9999), WebSocketsHandler)
server.serve_forever()
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