I am using web sockets to connect to localhost as seen below. I am using native web sockets on the client and express-ws on the server.

This was working fine and stopped for some reason. The only changes I can remember making were formatting using ESLint.

How can I troubleshoot this further. The server is showing no error. The client error gives no useful info.

CLIENT

const socket = new WebSocket('ws://localhost:3000/echo');

socket.addEventListener('error', function(event) {
  console.log('DEBUG: WebSocket error:', event);
});

SERVER

function ws(app) {
  const expressWs = require('express-ws')(app);
  console.log('DEBUG: websocket server up');
  app.ws('/echo', (ws, req) => {
    ws.on('message', (msg) => {
      ws.send(msg);
    });
  }); 
}
module.exports = ws;

CLIENT ERROR:

WebSocket connection to 'ws://localhost:3000/echo' failed: