Why can't create an instance?

Question

css

Here such a small problem was drawn here:

And here is my app.js shit code:

The code

'use strict';

var express = require('express'),
    path = require('path'),
    logger = require('morgan'),
    cookieParser = require('cookie-parser'),
    bodyParser = require('body-parser'),
    app = express(),
    WebSocketServer = new require('ws'),
    clients = {},
    webSocketServer = new WebSocketServer.Server({
        port: 8081
    }),
    msg = require("./bin/msg");

app.use(express.static('public'));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded());
app.use(cookieParser());


webSocketServer.on('connection', function (ws) {

    var id = Math.random();
    clients[id] = ws;

    //console.log("новое соединение " + id);

    ws.on('message', function (message) {
        console.log('получено сообщение ' + message);
        let msg = new Msg("кто-то", "кому-то", "Что-то", null, []);
        msg.send();
        for (var key in clients) {
            clients[key].send(message);
        }
    });

    ws.on('close', function () {
        //console.log('соединение закрыто ' + id);
        delete clients[id];
    });

});

app.get("/", (req, res) => {
    res.sendFile("index.html");
});
module.exports = app;

msg.js:

'use strict';
var db = require("./db"),
    Schema = db.Schema;


class Msg {
    constructor(from, to, text, date, ansewers) {
        this.from = from;
        this.to = to;
        this.text = text;
        this.date = date;
        this.ansewers = ansewers;
    }
    getSchema() {
        return new Schema({
            from: {
                type: String
            },
            to: {
                type: String
            },
            text: {
                type: String,
                default: "..."
            },
            date: {
                type: Date,
                default: Date.now
            },
        });
    }
    getModel() {
        return db.model("Msg", this.getSchema());
    }
    send() {
        let msgModel = this.getModel();
        let msg = new msgModel({
            from: this.from,
            to: this.to,
            text: this.text
        });
        msg.save(function(err, msg, affected){
            if(err)return err;
            console.log(arguments);
        });
    }
}

module.exports = Msg;

Help me please!

Answer 1

Why Msg? You imported it as msg - no wonder it is not defined.