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copied!<p>Here is a working example of a WebSocket client/server (client in Javascript, server in Python 2.6)</p> <p>It used examples from various places (including kanaka's answer/noVNC, and <a href="http://blog.new-bamboo.co.uk/2010/6/7/living-on-the-edge-of-the-websocket-protocol" rel="nofollow">this page</a> and <a href="http://dev.enekoalonso.com/2010/05/22/more-websockets-now-with-python/" rel="nofollow">this page</a>)</p> <p>Works with Chrome 10.0.648.127, Safari 5.0.3 and MobileSafari on iPad from iOS 4.3</p> <p>It's by no means well written code (the example HTML page is especially terrible) - use at your own risk and so on..</p> <pre><code>#!/usr/bin/env python import socket import threading import struct import hashlib PORT = 9876 def create_handshake_resp(handshake): final_line = "" lines = handshake.splitlines() for line in lines: parts = line.partition(": ") if parts[0] == "Sec-WebSocket-Key1": key1 = parts[2] elif parts[0] == "Sec-WebSocket-Key2": key2 = parts[2] elif parts[0] == "Host": host = parts[2] elif parts[0] == "Origin": origin = parts[2] final_line = line spaces1 = key1.count(" ") spaces2 = key2.count(" ") num1 = int("".join([c for c in key1 if c.isdigit()])) / spaces1 num2 = int("".join([c for c in key2 if c.isdigit()])) / spaces2 token = hashlib.md5(struct.pack('>II8s', num1, num2, final_line)).digest() return ( "HTTP/1.1 101 WebSocket Protocol Handshake\r\n" "Upgrade: WebSocket\r\n" "Connection: Upgrade\r\n" "Sec-WebSocket-Origin: %s\r\n" "Sec-WebSocket-Location: ws://%s/\r\n" "\r\n" "%s") % ( origin, host, token) def handle(s, addr): data = s.recv(1024) s.send(create_handshake_resp(data)) lock = threading.Lock() while 1: print "Waiting for data from", s, addr data = s.recv(1024) print "Done" if not data: print "No data" break print 'Data from', addr, ':', data # Broadcast received data to all clients lock.acquire() [conn.send(data) for conn in clients] lock.release() print 'Client closed:', addr lock.acquire() clients.remove(s) lock.release() s.close() def start_server(): s = socket.socket() s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.bind(('', PORT)) s.listen(1) while 1: conn, addr = s.accept() print 'Connected by', addr clients.append(conn) threading.Thread(target = handle, args = (conn, addr)).start() clients = [] start_server() </code></pre> <p>Also, a crappy example HTML page to show it working:</p> <pre><code><!DOCTYPE html> <html lang="en"> <head> <title>Test</title> <script type="application/javascript"> var ws; function init() { var servermsg = document.getElementById("servermsg"); ws = new WebSocket("ws://localhost:9876/"); ws.onopen = function(){ servermsg.innerHTML = servermsg.innerHTML + "<br>Server connected"; servermsg.innerHTML = servermsg.innerHTML + "<br>Sending message to server"; ws.send("Hello Mr. Server!"); }; ws.onmessage = function(e){ servermsg.innerHTML = servermsg.innerHTML + "<br>Recieved data: " + e.data; }; ws.onclose = function(){ console.log("Server disconnected"); servermsg.innerHTML = servermsg.innerHTML + "<br>Connected"; }; } function postmsg(){ var text = document.getElementById("message").value; ws.send(text); servermsg.innerHTML = servermsg.innerHTML + "<br>Sent: " + text; return false; } </script> </head> <body onload="init();"> <form action="" onSubmit="postmsg()"> <input type="text" name="message" value="" id="message"> <input type="submit" name="submit" value="" id="submit"> </form> <div id="servermsg"><h1>Message log:</h1></div> </body> </html> </code></pre>

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