Websockets not working over TLS (wss)

[ianhalpern]

Hi,

I've been trying to debug the issue with a simple socket.io app on GKE. Websockets/Socket.io works fine over HTTP (ws://) but when switching to HTTPS (wss://) the client does receive a valid response with a Sec-WebSocket-Accept header but within a second or two after the handshake the connection gets closed and no messages are relayed. Below is the configuration. I tried to keep it plain and simple.

Ingress:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: flask-ws-ingress
spec:
  rules:
  - host: my-domain.com
    http:
      paths:
      - path: /*
        backend:
          serviceName: flask-ws-app-svc
          servicePort: 80
  tls:
    - hosts:
      - my-domain.com
      secretName: domain-tls-cert

Service:

apiVersion: v1
kind: Service
metadata:
  name: flask-ws-app-svc
  labels:
    name: flask-ws-app
spec:
  ports:
  - port: 80
    targetPort: 8080
    protocol: TCP
    name: http
  type: ClusterIP
  selector:
    name: flask-ws-app

Deployment

apiVersion: apps/v1beta2
kind: Deployment
metadata:
  name: flask-ws-app
  labels:
    name: flask-ws-app
spec:
  replicas: 1
  selector:
    matchLabels:
      name: flask-ws-app
  template:
    metadata:
      name: flask-ws-app
      labels:
        name: flask-ws-app
    spec:
      containers:
        - name: flask-ws-app
          image: gcr.io/project/flask-ws-app:v3
          ports:
            - containerPort: 8080

Flask App

from flask import Flask, send_from_directory
from flask_socketio import SocketIO, send
import config

app = Flask(__name__)
app.config.from_object('config')
app.config["SECRET_KEY"] = "secret!"
socketio = SocketIO(app)

@socketio.on('message')
def handle_message(message):
    send('echo from server: '+message)

if __name__ == "__main__":
    socketio.run(app, port=config.PORT, debug=True)

[nisharma2023]

hi @ianhalpern how did you fix this issue? I am running into same.