[Python] How do I use Twisted (or Autobahn) to connect to a socket.io server?

I am trying to figure out a way to connect to a socket.io (node.js) server with a Python Twisted client. The server is a chat server which I didn't write, so I have no control over it. I tried a few things, mainly TCP connections, but I figured that I'll need to use the Websockets interface to communicate successfully.

Just to test out, I used the code from socket.io tutorial, http://socket.io/#how-to-use for the server.

var app = require('http').createServer(handler)
, io = require('socket.io').listen(app)
, fs = require('fs')

app.listen(8080);

function handler (req, res) {
fs.readFile(__dirname + '/index.html',
function (err, data) {
if (err) {
res.writeHead(500);
return res.end('Error loading index.html');
}

res.writeHead(200);
res.end(data);
});
}

io.sockets.on('connection', function (socket) {
socket.emit('news', { hello: 'world' });
socket.on('my other event', function (data) {
console.log(data);
});
});


For the client, I used the example code from this tutorial: (I know the callbacks don't match, but I just want to see if it will connect first, which it doesn't).

from twisted.internet import reactor
from autobahn.websocket import WebSocketClientFactory, \
WebSocketClientProtocol, \
connectWS


class EchoClientProtocol(WebSocketClientProtocol):

def sendHello(self):
self.sendMessage("Hello, world!")

def onOpen(self):
self.sendHello()

def onMessage(self, msg, binary):
print "Got echo: " + msg
reactor.callLater(1, self.sendHello)


if __name__ == '__main__':

factory = WebSocketClientFactory("ws://localhost:8080", debug = False)
factory.protocol = EchoClientProtocol
connectWS(factory)
reactor.run()


This is just to see if it will connect. The problem is, the socket.io server says: destroying non-socket.io upgrade, so I'm guessing the client isn't sending a proper UPGRADE header, but I'm not sure.

Am I missing something, or are Websocket implementations different across libraries, and that I'll need to do some digging in order for them to communicate? I had a feeling it was supposed to be quite easy. My question is, what do I change on the client so it will connect (complete handshake successfully and start accepting/sending frames)?

Finally, I would like to use Twisted, but I'm open to other suggestions. I understand the most straight forward will be making a socket.io client, but I only know Python.

After turning on logging, it shows this:

2013-11-14 22:11:29-0800 [-] Starting factory <autobahn.websocket.WebSocketClientFactory instance at 0xb6812080>
2013-11-14 22:11:30-0800 [Uninitialized]
[('debug', True, 'WebSocketClientFactory'),
('debugCodePaths', False, 'WebSocketClientFactory'),
('logOctets', True, 'WebSocketClientFactory'),
('logFrames', True, 'WebSocketClientFactory'),
('trackTimings', False, 'WebSocketClientFactory'),
('allowHixie76', False, 'WebSocketClientFactory'),
('utf8validateIncoming', True, 'WebSocketClientFactory'),
('applyMask', True, 'WebSocketClientFactory'),
('maxFramePayloadSize', 0, 'WebSocketClientFactory'),
('maxMessagePayloadSize', 0, 'WebSocketClientFactory'),
('autoFragmentSize', 0, 'WebSocketClientFactory'),
('failByDrop', True, 'WebSocketClientFactory'),
('echoCloseCodeReason', False, 'WebSocketClientFactory'),
('openHandshakeTimeout', 5, 'WebSocketClientFactory'),
('closeHandshakeTimeout', 1, 'WebSocketClientFactory'),
('tcpNoDelay', True, 'WebSocketClientFactory'),
('version', 18, 'WebSocketClientFactory'),
('acceptMaskedServerFrames', False, 'WebSocketClientFactory'),
('maskClientFrames', True, 'WebSocketClientFactory'),
('serverConnectionDropTimeout', 1, 'WebSocketClientFactory'),
('perMessageCompressionOffers', [], 'WebSocketClientFactory'),
('perMessageCompressionAccept',
<function <lambda> at 0x177ba30>,
'WebSocketClientFactory')]
2013-11-14 22:11:30-0800 [Uninitialized] connection to 127.0.0.1:8080 established
2013-11-14 22:11:30-0800 [Uninitialized] GET / HTTP/1.1
User-Agent: AutobahnPython/0.6.4
Host: localhost:8080
Upgrade: WebSocket
Connection: Upgrade
Pragma: no-cache
Cache-Control: no-cache
Sec-WebSocket-Key: TOy2OL5T6VwzaiX93cesPw==
Sec-WebSocket-Version: 13

2013-11-14 22:11:30-0800 [Uninitialized] TX Octets to 127.0.0.1:8080 : sync = False, octets = 474554202f20485454502f312e310d0a557365722d4167656e743a204175746f6261686e5079
74686f6e2f302e362e340d0a486f73743a206c6f63616c686f73743a383038300d0a557067726164653a20576562536f636b65740d0a436f6e6e656374696f6e3a20557067726164650d0a507261676d613a206e6f
2d63616368650d0a43616368652d436f6e74726f6c3a206e6f2d63616368650d0a5365632d576562536f636b65742d4b65793a20544f79324f4c35543656777a616958393363657350773d3d0d0a5365632d576562
536f636b65742d56657273696f6e3a2031330d0a0d0a
2013-11-14 22:11:30-0800 [EchoClientProtocol,client] connection to 127.0.0.1:8080 lost
2013-11-14 22:11:30-0800 [EchoClientProtocol,client] Stopping factory <autobahn.websocket.WebSocketClientFactory instance at 0xb6812080>


I take this as socket.io not wanting let non-socket.io connections connect, which is kind of odd. If anyone knows a workaround or any ideas please share them.

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