How to securely connect to Bitstamp Websocket v2.0 API with python websockets? Certrificate verification error

Question

I'm trying to get real time bitcoin price data from the Bitstamp Websocket v2.0 API. Where can I get the certificate if needed? If download of the certificate is automatic, how can I make sure that it is possible for python to verify the received certificate?

The documentation on the Bitstamp website is rather scarce on this matter. Here's a quote from Bitstamp api documentation:

"Once you open a connection via websocket handshake (using HTTP upgrade header), you can subscribe to desired channels."

Bitstamp api docs: https://www.bitstamp.net/websocket/v2/

Tried searching in websockets documentation: https://websockets.readthedocs.io/en/stable/

I have looked into websockets and ssl. Now I know a bit about the handshake but still after much trying and searching I can't figure out what to do.

import asyncio
import websockets

async def bitstamp_ticker():
    async with websockets.connect(
            'wss://ws.bitstamp.net', ssl=True) as websocket:
        pass

asyncio.get_event_loop().run_until_complete(bitstamp_ticker())

From what I understand in the websocket documentation adding ssl=True should be enough to establish a secure connection. But it seems that maybe the bitstamp certificate is not recognized by a Certificate Authority built into Python 3.6. and this is why the error occurs?

ssl.SSLError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:852)

Answer 1

I didn't spend time looking into this ssl cert issue for Bitstamp. But I just disabled ssl cert verification to make the web-socket market data push work. Below is the sample code, and appreciated if you could share your future progress on this issue.

# -*- coding: utf-8 -*-
import websocket
import json
import ssl

bitstamp_endpoint = 'wss://ws.bitstamp.net'


def subscribe_marketdata(ws):
    params = {
        'event': 'bts:subscribe',
        'data': {
            'channel': 'order_book_btcusd'
        }
    }
    market_depth_subscription = json.dumps(params)

    ws.send(market_depth_subscription)


def on_open(ws):
    print('web-socket connected.')
    subscribe_marketdata(ws)


def on_message(ws, data):
    data = json.loads(data)
    print(data)


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


if __name__ == '__main__':
    marketdata_ws = websocket.WebSocketApp(bitstamp_endpoint, on_open=on_open, on_message=on_message, on_error=on_error)
    marketdata_ws.run_forever(sslopt={'cert_reqs': ssl.CERT_NONE})