example of an express session

index.js

const express = require("express");
const morgan = require("morgan");
const expressSession = require("express-session");
const mongoose = require('mongoose');
const MongoStore = require('connect-mongo')(expressSession);

const app = express();

const dbOptions = { useNewUrlParser: true, useUnifiedTopology: true }
mongoose.connect("mongodb://localhost:27017/test-with-mongo-store", dbOptions, (err) => {
  if (err) {
    console.log('not connected ❌')
  } else {
    console.log('connected ✅')
  }
})

app.use(expressSession({
  secret: 'secret',
  resave: false,
  saveUninitialized: false
}));

app.use(morgan('dev'));

app.get("/increment", (req, res) => {
  req.session.pageCount = req.session.pageCount ? req.session.pageCount + 1 : 1;
  res.send({viewed: req.session.pageCount});
})

app.listen(5000, () => console.log('listening on port 5000'));

package.json

{
  "name": "backend",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "nodemon index.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "connect-mongo": "^3.0.0",
    "express": "^4.17.1",
    "express-session": "^1.17.0",
    "mongoose": "^5.7.5",
    "morgan": "^1.9.1"
  }
}