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POAlways an Error on the First Message
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copied!<p>Currently I'm working on setting up a basic WebSockets script. I can get the client to connect to the server, but whenever the server sends the first message to the client the client registers and error, and from what I can tell the readyState is open, and should allow the message to come through. The message has the correct beginning of /x00 and /xff. I can't figure out what's wrong.</p> <p>EDIT: Here are the codes that seem to be causing whatever the error is. data.js just holds what the Python server used to set up the server so I only have to change one file when I test it out and the port hasn't timed out yet.</p> <p>Client-side:</p> <pre><code><html> <head> <script type="text/javascript" src="data.js"> </script> <script type="text/javascript"> var ws, error init = function() { ws = new WebSocket("ws://127.0.0.1:"+port+"/websockets/main.py") ws.onopen = function() { console.log("Connected") log("Connected") } ws.onmessage = function(e) { console.log("Received data") log(e.data) } ws.onerror = function(e) { console.log(e) ws.send("Error occurred. Resend") } } log = function(msg) { document.getElementById("log").appendChild(document.createElement("br")) document.getElementById("log").innerHTML = document.getElementById("log").innerHTML+msg } </script> </head> <body onload="init()"> <div id="log"> </div> </body> </html> </code></pre> <p>Server-side:</p> <pre><code>import threading, hashlib, socket, time, re, struct class WebSocketThread(threading.Thread): def __init__(self, channel, details, websocket): self.channel = channel self.details = details self.websocket = websocket threading.Thread.__init__(self) def run(self): print("> Received connection ", self.details[0]) self.handshake(self.channel) while True: self.interact(self.channel) def finduser(self, client): for user in self.websocket.users: if user.socket == client: return user return 0 def send_data(self, user, data): user.socket.send(self.wrap(data)) print ("> Sent data", data, "to", user) def recv_data(self, client, count): data = client.recv(count) return data def handshake(self, client): shake = self.recv_data(client, 256) our_handshake = self.create_response(shake) client.send(our_handshake) print ("> Accepted client ", self.finduser(client)) self.send_data(self.finduser(client), "Test") def interact(self, client): users = self.websocket.users this_user = self.finduser(client) data = self.unwrap(self.recv_data(client, 256)) print ("> Received data ", data, "from", this_user) def create_response(self, data): key3 = "" lines = data.splitlines() resource = re.compile("GET (.*) HTTP").findall(data) resource = resource[0] for line in lines: parts = line.partition(": ") if parts[0] == "Host": host = parts[2] elif parts[0] == "Origin": origin = parts[2] elif parts[0] == "Sec-WebSocket-Key1": key1 = parts[2] elif parts[0] == "Sec-WebSocket-Key2": key2 = parts[2] key3 = 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, key3)).digest() return "HTTP/1.1 101 WebSocket Protocol Handshake\r\nUpgrade: WebSocket\r\nConnection: Upgrade\r\nSec-WebSocket-Origin: %s\r\nSec-WebSocket-Location: ws://%s%s\r\nSec-WebSocket-Protocol: sample\r\n\r\n%s\r\n"% (origin, host, resource, token) def unwrap(self, data): return data[1:-1] def wrap(self, data): return ("\x00"+data+"\xff") </code></pre>

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