I'm trying to abstract a tutorial for MEAN stack to use MongoAtlas rather than a local instance.
My Mongoose connection to Atlas DB is working (in so far as I can connect to the DB). But I'm not able to do a save(). I believe that this is something to do with the way I'm creating my connection object, but I don't seem to be able to put my finger on the problem.

I assumed that by adding bufferCommands = false that this would tell me that the reason it wasn't working was I'd opened the connection object wrongly, but I'm not seeing any error - just hanging.

product.js

var mongoose = require('mongoose');
var db = mongoose.connection;
var Schema = mongoose.Schema;

var schema = new Schema (
 imagePath: type: String, required: true,
 title: type: String, required: true,
 description: type: String, required: true,
 price: type: Number, required:true
);
var connection = mongoose.createConnection('mongodb+srv://<user>:<password>@cluster0-dpwmr.gcp.mongodb.net/Shopping?retryWrites=true', useNewUrlParser:true)

module.exports = connection.model('Product', schema);

product-seeder.js

var Product = require('../models/product');

var mongoose = require('mongoose');
//mongoose.set('bufferCommands', false);
var products =[ 
 new Product(
 imagePath:'https://picsum.photos/250/?random',
 title: 'Item 1',
 description: 'This is a thing',
 price: 10
 ),
 new Product(
 imagePath:'https://picsum.photos/251/?random',
 title: 'Item 2',
 description: 'This is another thing',
 price: 14
 ),
 new Product(
 imagePath:'https://picsum.photos/253/?random',
 title: 'Item 3',
 description: 'This is a slightly longer description',
 price: 30
 )
];


var done = 0;
for (i=0; i++; i<products.length)
 products[i].save(function(err, res)
 if (err)
 console.log(err);
 exit();
 
 done++;
 if (done === products.length)
 exit();
 
 );


function exit()
 mongoose.disconnect();

I expected this to create a new document 'products' and write to it in the Shopping collection, but that's not happening, just lots of nothing.

I've got this working with a combination of:

• Using mongoose.connect()


• Adding the DB name to the options object


• Making sure that the DB writes are done with proper promises, not weird loops.

var mongoose = require('mongoose');
var db = mongoose.connection;
var Schema = mongoose.Schema;

var schema = new Schema (
 imagePath: type: String, required: true,
 title: type: String, required: true,
 description: type: String, required: true,
 price: type: Number, required:true
);
mongoose.connect('mongodb+srv://<UserName>:<Password>@cluster0-dpwmr.gcp.mongodb.net/', dbName:'Shopping', useNewUrlParser:true)
.then( () => 
 console.log('Connection to the Atlas Cluster is successful!')
 )
 .catch( (err) => console.error(err));

const conn = mongoose.connection;
module.exports = mongoose.model('Product', schema);

var Product = require('../models/product');

var mongoose = require('mongoose');

var products =[ 
 new Product(
 imagePath:'https://picsum.photos/250/?random',
 title: 'Item 1',
 description: 'This is a thing',
 price: 10
 ),
 new Product(
 imagePath:'https://picsum.photos/251/?random',
 title: 'Item 2',
 description: 'This is another thing',
 price: 14
 ),
 new Product(
 imagePath:'https://picsum.photos/253/?random',
 title: 'Item 3',
 description: 'This is a slightly longer description',
 price: 30
 )
];
const conn = mongoose.connection;

processArray(products);

async function processArray (array) 
 for (const item of products)
 console.log (item)
 await item.save();
 
 conn.close();