MERN Stack
MERN Full Form
How to Become a MERN Stack Developer?
Difference between MEAN Stack and MERN Stack
Best Hosting Platforms for MERN Projects
Getting Started with React & Frontend
• React Introduction
• React Environment Setup
• React Components
• ReactJS Props - Set 1
• ReactJS State
• React Forms
• ReactJS Lists
• Create ToDo App using ReactJS
Redux Setup and basics
• Introduction to Redux (Action, Reducers and Store)
• Redux and The Flux Architecture
• React Redux Hooks: useSelector and useDispatch.
• What are Action's creators in React Redux?
• What is Redux Thunk?
• Creating custom middlewares in React Redux
• Common middleware libraries used in Redux
Express and Mongo Setup
• Mongo with Express Tutorial
• How to Install MongoDB on Windows?
• How to install Express in a Node project?
• Mongoose Module Introduction
• Mongoose Connections
• Nodejs - Connect MongoDB with Node app using MongooseJS
• Node.js CRUD Operations Using Mongoose and MongoDB Atlas
• Signup Form Using Node.js and MongoDB
API Routing and Authentication
• Routing in Node
• How to create routes using Express and Postman?
• Difference between application level and router level middleware in Express?
• How to handle authentication in Node?
• JWT Authentication with Node.js
• How to implement JWT authentication in Express app ?
Postman- Backend Testing
• Introduction to Postman for API Development
• Basics of API Testing Using Postman
• How to use postman for testing express application
• How to send different types of requests (GET, POST, PUT, DELETE) in Postman.
• How to test GET Method of express with Postman ?
• How to test POST Method of Express with Postman?
• How to test DELETE Method of Express with Postman ?
• How to create and write tests for API requests in Postman?
MERN Stack Projects
• Stock Market Portfolio App using MERN Stack
• Hospital Management Application using MERN Stack
• 35+ MERN Stack Projects with Source Code [2024]
Top MERN Stack Interview Questions

A Mongoose connection is a Node.js module that establishes and manages connections between a Node.js application and a MongoDB database. It optimizes resource utilization, handles connection pooling, and manages errors, facilitating efficient data operations.

Why do we need Mongoose Connections?

Steps to Establishing Mongoose Connections

npm install mongoose

const mongoose = require('mongoose');

mongoose.connect('mongodb://localhost/mydatabase', {
    useNewUrlParser: true,
    useUnifiedTopology: true,
})
.then(() => {
    console.log('Connected to MongoDB');
})
.catch((error) => {
    console.error('Error connecting to MongoDB:', error);
});

const db = mongoose.connection;

db.on('error', (error) => {
    console.error('MongoDB connection error:', error);
});

db.once('open', () => {
    console.log('Connected to MongoDB');
});

db.on('disconnected', () => {
    console.log('Disconnected from MongoDB');
});

process.on('SIGINT', () => {
    mongoose.connection.close(() => {
        console.log('Mongoose connection is disconnected due to application termination');
        process.exit(0);
    });
});

Connection Events and Error Handling

Connection Events in mongoose: In Mongoose, connection events play an important role in monitoring and controlling the interaction between your Node.js application and MongoDB databases. Key connection events include:

const mongoose = require('mongoose');

// MongoDB URI
const dbURI = 'mongodb://localhost/mydatabase';

// Connect to MongoDB
mongoose.connect(dbURI, { useNewUrlParser: true, useUnifiedTopology: true });

// Event handling for successful connection
mongoose.connection.on('connected', () => {
    console.log('Mongoose connected to ' + dbURI);
});

// Event handling for connection error
mongoose.connection.on('error', (err) => {
    console.error('Mongoose connection error: ' + err);
});

// Event handling when the connection is disconnected
mongoose.connection.on('disconnected', () => {
    console.log('Mongoose disconnected');
});

// Close the Mongoose connection when the Node.js process exits
process.on('SIGINT', () => {
    mongoose.connection.close(() => {
        console.log('Mongoose connection closed through app termination');
        process.exit(0);
    });
});

// Or you can close the connection
//explicitly when you're done with it
// mongoose.connection.close();