How to connect to poloniex.com websocket api using a python library

Question

I am trying to connect to wss://api.poloniex.com and subscribe to ticker. I can't find any working example in python. I have tried to use autobahn/twisted and websocket-client 0.32.0.

The purpose of this is to get real time ticker data and store it in a mysql database.

So far I have tried to use examples provided in library documentation. They work for localhost or the test server but if I change to wss://api.poloniex.com I get a bunch of errors.

here is my attempt using websocket-client 0.32.0:

from websocket import create_connection
ws = create_connection("wss://api.poloniex.com")
ws.send("ticker")
result = ws.recv()
print "Received '%s'" % result
ws.close()

and this is using autobahn/twisted:

from autobahn.twisted.websocket import WebSocketClientProtocol
from autobahn.twisted.websocket import WebSocketClientFactory


class MyClientProtocol(WebSocketClientProtocol):

    def onConnect(self, response):
        print("Server connected: {0}".format(response.peer))

    def onOpen(self):
        print("WebSocket connection open.")

        def hello():
            self.sendMessage(u"ticker".encode('utf8'))
            self.sendMessage(b"\x00\x01\x03\x04", isBinary=True)
            self.factory.reactor.callLater(1, hello)

        # start sending messages every second ..
        hello()

    def onMessage(self, payload, isBinary):
        if isBinary:
            print("Binary message received: {0} bytes".format(len(payload)))
        else:
            print("Text message received: {0}".format(payload.decode('utf8')))

    def onClose(self, wasClean, code, reason):
        print("WebSocket connection closed: {0}".format(reason))


if __name__ == '__main__':

    import sys

    from twisted.python import log
    from twisted.internet import reactor

    log.startLogging(sys.stdout)

    factory = WebSocketClientFactory("wss://api.poloniex.com", debug=False)
    factory.protocol = MyClientProtocol

    reactor.connectTCP("wss://api.poloniex.com", 9000, factory)
    reactor.run()

A complete but simple example showing how to connect and subscribe to to a websocket push api using any python library would be greatly appreciated.

Answer 1

This uses the undocumented websocket endpoint because Poloniex has pulled support for the original WAMP socket endpoint.

import websocket
import thread
import time
import json

def on_message(ws, message):
    print(message)

def on_error(ws, error):
    print(error)

def on_close(ws):
    print("### closed ###")

def on_open(ws):
    print("ONOPEN")
    def run(*args):
        ws.send(json.dumps({'command':'subscribe','channel':1001}))
        ws.send(json.dumps({'command':'subscribe','channel':1002}))
        ws.send(json.dumps({'command':'subscribe','channel':1003}))
        ws.send(json.dumps({'command':'subscribe','channel':'BTC_XMR'}))
        while True:
            time.sleep(1)
        ws.close()
        print("thread terminating...")
    thread.start_new_thread(run, ())


if __name__ == "__main__":
    websocket.enableTrace(True)
    ws = websocket.WebSocketApp("wss://api2.poloniex.com/",
                              on_message = on_message,
                              on_error = on_error,
                              on_close = on_close)
    ws.on_open = on_open
    ws.run_forever()

The channels are:

1001 = trollbox (you will get nothing but a heartbeat)
1002 = ticker
1003 = base coin 24h volume stats
1010 = heartbeat
'MARKET_PAIR' = market order books