trying to connect to mongodb Atlas using nodeJs - node.js

Question

I am working on a small project(REST API) using nodeJs + MongoDB. I have been able to install MongoDB locally and connect to it using mongoose. However for some reason, when I try to connect using MongoDB Atlas it fails. It looks like it connects but then after 2 seconds, I get an error message saying sockets closed(see error below). I have no clue what is going on. I have whitelisted my IP, checked my login info to make sure I am using the correct password and indeed I am using because I am able to connect using MongoDB compass. Any help is greatly appreciated.
My current local ENV package versions are:
nodeJs:V9.7.1
mongoose:V6.1
=== MongoDb Atlas ===
mongodb:3.6
Below is the code that I am using to connect to the database:
var express = require('express'),
port = process.env.PORT || 3000,
mongoose = require('mongoose'),
user = require('./api/models/userModel'),
config = require('./api/config');
bodyParser = require('body-parser');
var authRoutes = require('./api/routes/authRoutes'),
userRoutes = require('./api/routes/userRoutes'),
reviewRoutes = require('./api/routes/reviewRoutes');
const swaggerUi = require('swagger-ui-express');
const swaggerDocument = require('./swagger.json');
mongoose.Promise = global.Promise;
mongoose.connect('mongodb://user:myPass#cluster0-shard-00-00 zd6jq.mongodb.net/myDb');
app.use(bodyParser.urlencoded({extended: true}));
app.use(bodyParser.json());
//Swagger Info
var options = {
explorer : true
};
app.use('/swagger', swaggerUi.serve, swaggerUi.setup(swaggerDocument, options));
//END Swagger Info
//REGISTER ROUTES
userRoutes(app);
authRoutes(app);
reviewRoutes(app);
app.listen(port);
console.log('iReview RESTful API server listenning on port: ' + port);
module.exports = app;
====ERROR MESSAGE ===
/Users/mdiez/node_test/node_modules/mongodb/lib/server.js:228
process.nextTick(function() { throw err; })
^
MongoError: server cluster0-shard-00-00-zd6jq.mongodb.net:27017 sockets closed
at Pool.<anonymous> (/Users/mdiez/node_test/node_modules/mongodb-core/lib/topologies/server.js:325:47)
at Object.onceWrapper (events.js:219:13)
at Pool.emit (events.js:127:13)
at Connection.<anonymous> (/Users/mdiez/node_test/node_modules/mongodb-core/lib/connection/pool.js:101:12)
at Object.onceWrapper (events.js:219:13)
at Connection.emit (events.js:127:13)
at Socket.<anonymous> (/Users/mdiez/node_test/node_modules/mongodb-core/lib/connection/connection.js:142:12)
at Object.onceWrapper (events.js:219:13)
at Socket.emit (events.js:127:13)
at TCP._handle.close [as _onclose] (net.js:558:12)

Answer 1

var uri = 'mongodb://<usernamr>:<password>#<clustername>/<dbname>?ssl=true&replicaSet=<replica setname>&authSource=admin';
var db = mongoose.connect(uri).catch((error) => { console.log(error); });
Specify the replica set name, ssl true and authentication database. This is based on reference from Atlas documentation.

Answer 2

You can use this code to connect to Compass and Application. You just need to the following:
replace all the three primary and secondary shard from Cluster -> Overview
replace natours-app with your cluster name.
Compass:
mongodb://babar_bahadur:PASSWORD#natours-app-shard-00-00-ybksz.mongodb.net:27017,natours-app-shard-00-01-ybksz.mongodb.net:27017,natours-app-shard-00-02-ybksz.mongodb.net:27017/test?authSource=admin&replicaSet=natours-app1-shard-0&readPreference=primary&appname=MongoDB%20Compass&retryWrites=true&ssl=true
Application:
mongodb://babar_bahadur:PASSWORD#natours-app-shard-00-00-ybksz.mongodb.net:27017,natours-app-shard-00-01-ybksz.mongodb.net:27017,natours-app-shard-00-02-ybksz.mongodb.net:27017/test?ssl=true&replicaSet=natours-app-shard-0&authSource=admin&retryWrites=true