homework/js/06_chat/index.js

var app = require("express")();
var http = require("http").Server(app);
var io = require("socket.io")(http);
const cors = require("cors");

app.use(cors());

app.get("/", function (req, res) {
    res.sendFile(__dirname + "/index.html");
});

io.on("connection", function (socket) {
    console.log("an user connected with id", socket.id);

    io.emit("msg", {
        nick: "--Администрация--",
        message: `у нас новенький (socket.id: ${socket.id})`,
    });

    socket.on("msg", function (msg) {
        if (msg && msg.message && msg.nick) {
            io.emit("msg", msg);
        } else {
            console.log("WRONG MESSAGE", msg);
        }
    });

    socket.on("disconnect", function () {
        console.log("user disconnected " + socket.id);

        io.emit("msg", {
            nick: "--Администрация--",
            message: `пользователь покинул чат (socket.id: ${socket.id})`,
        });
    });
});

http.listen(4000, function () {
    console.log("listening on *:4000");
});