set database and collection using mongoose - node.js

Question

How do I set my database and collection using mongoose ? I am trying to connect to a mongodb atlas database using mongoose. My database is called "test_db" and collection name is "users" where would I specify that information ?
This is my shema (data.js):
// /backend/data.js
const mongoose = require("mongoose");
const Schema = mongoose.Schema;
// this will be our data base's data structure
const DataSchema = new Schema(
{
_id: Number,
name: String,
password: String
}
);
// export the new Schema so we could modify it using Node.js
module.exports = mongoose.model("users", DataSchema);
and this is server.js:
const mongoose = require('mongoose');
const express = require('express');
var cors = require('cors');
const bodyParser = require('body-parser');
const logger = require('morgan');
const Data = require('./data');
const API_PORT = 3001;
const app = express();
app.use(cors());
const router = express.Router();
// this is our MongoDB database
const dbRoute = 'mongodb+srv://<user>:<password>#cluster0-bmihj.mongodb.net/test?retryWrites=true&w=majority';
;
// connects our back end code with the database
const conn = mongoose.connect(dbRoute, { useNewUrlParser: true });
//let db = mongoose.connection;
const db = conn.db('test_db');
var MyModel = mongoose.model('Test', new Schema({ name: String }));
db.once('open', () => console.log('connected to the database'));
// checks if connection with the database is successful
db.on('error', console.error.bind(console, 'MongoDB connection error:'));
// this is our get method
// this method fetches all available data in our database
router.get('/getData', (req, res) => {
Data.find((err, data) => {
if (err) return res.json({ success: false, error: err });
return res.json({ success: true, data: data });
});
});

Answer 1

Through this line, you are connected to MongoDB:
const conn = mongoose.connect(dbRoute, { useNewUrlParser: true })
Consider:
dbRoute = mongodb://DB-username:DBpassword#ds245901.mlab.com:44422/Database-Name";
Here is your data information
DB-username = Your database user name
DBpassword = Your database password
Database-Name = Your database name (which database you want to use)
Therefore, no need to connect to your desired database like this:
const db = conn.db('test_db');