const express = require('express'); const { createServer } = require("http"); const { Server } = require("socket.io"); const { instrument } = require("@socket.io/admin-ui"); const app = express(); const httpServer = createServer(app); const io = new Server(httpServer, { cors: { origin: 'https://admin.socket.io', credentials: true }, }); const port = process.env.PORT || 5000; app.use(express.static(__dirname + '/fiddle_public')); io.on('connection', socket => { console.log(`connect auth=${JSON.stringify(socket.handshake.auth)} sid=${socket.id}`); socket.emit('hello', 1, '2', { hello: 'you' }); socket.on('disconnect', (reason) => { console.log(`disconnect ${socket.id}, reason: ${reason}`); }); }); instrument(io, {auth: false, mode: 'development'}); httpServer.listen(port, () => console.log(`server listening on port ${port}`));