I tried to build a Flask application including socket io server. It works well on local side. But when I deployed on aws ec2 instance(ubuntu system), I got following error.

websocket connection issue

Here is my nginx configuration.

nginx configuration

Client side code snippet is as follows.

var socket = io.connect('/', {
        transports: ["websocket"],
        cors: {
          origin: "*",
        },
      });

Server side code snippet is as follows.

from flask_socketio import SocketIO
from flask_cors import CORS

app = Flask(__name__)
CORS(app,resources={r"/*":{"origins":"*"}})
socketio = SocketIO(app,cors_allowed_origins="*")

I am not sure how to fix

I tried to figure it out by adding nginx configuration, but it didn’t work.