dotenv
//first install this
npm install dotenv
//then add this on the top of the your code
require("dotenv").config();
//first create file with name of .env
DB_HOST=localhost
DB_USER=root
DB_PASS=s1mpl3
//then use it
const db = require('db')
db.connect({
host: process.env.DB_HOST,
username: process.env.DB_USER,
password: process.env.DB_PASS
})