Node Js Express Study Notes

API Versioning and Best Practices

Learn common strategies for versioning Express APIs and best practices for building maintainable endpoints.

Async/Await in Node.js

Writing asynchronous code that reads like synchronous code using the async/await syntax built on Promises.

Authentication Basics and JWT

Learn how authentication works in web APIs and how JSON Web Tokens (JWT) provide a stateless way to verify user identity.

Callbacks in Node.js

How Node.js uses callback functions to handle asynchronous operations without blocking the main thread.

Common Node.js & Express Pitfalls

Real-world mistakes developers make with Node.js and Express, why they're harmful, and how to fix them.

Connecting to MongoDB with Mongoose

Learn how to connect an Express app to MongoDB using Mongoose schemas, models, and connection management.

Connecting to SQL Databases in Node.js

Learn how to connect Node.js to SQL databases like PostgreSQL and MySQL using connection pools and parameterized queries.

CRUD Operations in Express

Build complete Create, Read, Update, and Delete route handlers in Express using a database model.

Data Validation in Express

Validate incoming request data in Express using schema-based validation before it reaches your database layer.

Debugging Node.js Applications

Learn to debug Node.js apps using the built-in inspector, console methods, and Chrome DevTools.

Deploying Node.js Apps

Understand process managers, containerization, and common hosting options for deploying Node.js applications.

Environment Variables and Configuration

Learn how to manage configuration and secrets in Node.js apps using environment variables and dotenv.

The Error-First Callback Pattern

The Node.js convention of passing an error as the first callback argument for consistent async error handling.

Error Handling in Express

Master synchronous and asynchronous error handling in Express using 4-argument error middleware.

The events Module and EventEmitter

Learn how Node's EventEmitter class enables the observer pattern used throughout the Node.js core APIs.

Express Application Structure

Learn how to organize a growing Express project into routes, controllers, middleware, and config folders.

Common Express Interview Questions

Frequently asked Express.js interview questions covering middleware, routing, and error handling, with accurate answers.

The fs Module in Node.js

Learn how to read, write, and manage files using Node's built-in fs module with sync, async, and promise-based APIs.

Handling JSON Requests in Express

Learn how to parse incoming JSON payloads in Express using the built-in express.json() middleware.

Introduction to Express

Learn what Express is, why it exists on top of Node's http module, and how to create your first Express server.

Introduction to Node.js

Learn what Node.js is, why it exists, and how it lets JavaScript run outside the browser on servers.

Logging in Node.js Apps

Learn why console.log is insufficient in production and how to implement structured logging with Winston or Pino.

Middleware in Express

Master the Express middleware chain, the next() function, and the special error-handling middleware signature.

Node.js Architecture and the Event Loop

Understand Node.js's single-threaded, non-blocking architecture and how the event loop phases process callbacks.