Issue to handle mongoDB with nodejs (using express and handlebars) - node.js

Question

Given is:
/routes/index.js
var express = require('express');
var router = express.Router();
//var mongo = require('mongodb').MongoClient;
//var objectId = require('mongodb').ObjectID;
var mongo = require('mongodb');
var assert = require('assert');
var url = 'mongodb://localhost:27017/test';
/* GET home page. */
router.get('/', function(req, res, next) {
res.render('index');
});
router.post('/insert', function(req, res, next) {
var item = {
title: req.body.title,
content: req.body.content,
author: req.body.author
};
mongo.connect(url, function(err, db) {
assert.equal(null, err);
db.collection('userdata').insertOne(item, function(err, result) {
assert.equal(null, err);
console.log('Item inserted');
db.close();
});
});
res.redirect('/');
});
app.js
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var hbs = require('express-handlebars');
var expressValidator = require('express-validator');
var expressSession = require('express-session');
var indexRouter = require('./routes/index');
var usersRouter = require('./routes/users');
var app = express();
// view engine setup
app.engine('hbs', hbs({extname: 'hbs', defaultLayout: 'layout', layoutsDir: __dirname + '/views/layouts/'}));
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'hbs');
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public'))); eingetragen)
app.use(expressValidator());
app.use(express.static(path.join(__dirname, 'public')));
app.use(expressSession({secret: "eefa56_50cacb_34634f", saveUninitialized: false, resave: false})); // dafault storage is RAM, otherwise kann ich in der API von express-session rumwühlen, da der storage serverseitig in einer DB erfolgt
app.use('/', indexRouter);
app.use('/users', usersRouter);
...
package.json
{
"name": "sample_express_app(POST_GET_handlebars)",
"version": "0.0.0",
"private": true,
"scripts": {
"start": "node ./bin/www"
},
"dependencies": {
"assert": "^1.4.1",
"body-parser": "^1.18.3",
"cookie-parser": "~1.4.3",
"debug": "~2.6.9",
"express": "~4.16.0",
"express-handlenter": "^3.0.0",
"express-session": "^1.15.6",
"express-validator": "^5.3.0",
"http-errors": "~1.6.2",
"mongodb": "^3.1.4",
"morgan": "~1.9.0"
}
}
The mongoDB server is running and there is no issue to manipulate the database in the CMD. It especially deals with the router.post('/insert' ... in /routes/index.js. There is something wrong(but maybe at another point too).
I also tried it with this (either I get the error db.collection('userdata').insert(... --> 'db.collection is not a function' or db.userdata.insert(... --> 'cannot read property insert'):
1)
db.runCommand({
insert: "userdata",
documents: [ item ]
}
)
2)
db.collection('userdata').insertOne(item, function(err, result) {
assert.equal(null, err);
console.log('Item inserted');
db.close();
});
3)
db.userdata.insert(item, function(err, result) {
assert.equal(null, err);
console.log('Item inserted');
db.close();
});

Answer 1

Native mongoDB driver works with the help of MongoClient.
Make changes in the index.js file
var mongo = require('mongodb').MongoClient;
var url = 'mongodb://localhost:27017';
mongo.connect(url, function(err, client) {
const db = client.db(dbName);
//your db queries
})
refer mongodb