How do I fix a server side socket.io error?

问题

I have the following lines of code in my index.js file:

    const express = require('express');
    const app = express();
    const server = require('http').Server(app);
    const io = require('socket.io').listen(server);

When I start my server with: node --inspect server/index.js

I get: TypeError: require(...).listen is not a function.

Any and all help appreciated!

回答1:

You need http server. The correct way to start a socket server is,

const express = require("express");
const http = require("http");
const app = express();
const server = http.createServer(app)
const socketio = require('socket.io')
const io = socketio(server);

io.on("connection", socket => {
    console.log("connected");
    socket.on("welcome", (data) => {
        console.log("welcome message", data);
    })
});
server.listen(3000, () => console.log(`listen on port ${port}`)) 

The client,

const io =  require("socket.io-client");
let socket = io.connect("http://localhost:3000");
socket.emit("welcome", "Hi");

来源：https://stackoverflow.com/questions/65265662/how-do-i-fix-a-server-side-socket-io-error