Gain insights into Express.js essentials—routing, middleware, and RESTful APIs. Learn to integrate MongoDB, JWT authentication, validation, real-time features, and logging for scalable back-end apps.

express.tar.gz

JWT_SECRET

NODE_ENV

Express App

Express code

Express code-module

Express code-silent

Express App-p4000

Express App-test

Express App-database

Express App-database-tmux

Express App-uploads

Express-mysql

Express.js is a popular Node.js framework, especially useful for building APIs and server-side apps. It’s lightweight, unopinionated, and flexible, giving you full control over how your app is structured. Whether new to backend development or ready to build production-grade services using JavaScript, Express is a great place to start.

In this course, you’ll begin with a quick review of Node.js and asynchronous JavaScript. Then, you’ll cover Express.js essentials like routing, middleware, and modular app structure. You’ll learn to build RESTful APIs, connect your app to a database, and implement JSON web tokens (JWT) authentication. You’ll also explore validation and sanitization for added security. Finally, you’ll understand templating engines, real-time features using Socket.IO, and structured logging using Winston.

After completing this course, you’ll have a solid grasp of Express.js and the confidence to build secure, scalable, production-ready backend applications from scratch.

Learn Express.js

Which built-in middleware would you use to serve files like HTML, CSS, or JS in an Express app?

Which built-in middleware would you use to serve files like HTML, CSS, or JS in an Express app?

Parsing nested objects in URL-encoded data

What does the `extended: true` option in `express.urlencoded()` enable?

What does the <code>extended: true</code> option in <code>express.urlencoded()</code> enable?

What is a third-party middleware for logging HTTP requests in Express?

What is a third-party middleware for logging HTTP requests in Express?

What is the main purpose of Helmet in an Express app?

What is the main purpose of Helmet in an Express app?

What type of attack does Helmet help mitigate using the `X-Frame-Options` header?

What type of attack does Helmet help mitigate using the <code>X-Frame-Options</code> header?

Express automatically moves to the next route.

The error handling middleware is executed by default.

The server crashes with an uncaught exception.

What happens if `next()` is *not* called in a custom middleware and no response is sent?

What happens if <code>next()</code> is not called in a custom middleware and no response is sent?

Because Express executes middleware in reverse order

To ensure it catches errors from all preceding middleware and routes

To log all incoming requests before processing

Why is the error handling middleware required to be placed after all routes and other middleware?

Why is the error handling middleware required to be placed after all routes and other middleware?

It applies the middleware globally to all routes.

It makes it easier to reuse middleware across unrelated routes.

It allows middleware logic to be defined inline in the handler.

It helps tailor middleware application specific to the route and improves readability.

What is the benefit of attaching middleware directly in route definitions?

What is the benefit of attaching middleware directly in route definitions?

They can be reused across multiple routes.

They execute faster than built-in middleware.

What is the benefit of writing custom middleware as separate functions?

What is the benefit of writing custom middleware as separate functions?

Test your understanding of built-in, third-party, and custom middleware—how to use, structure, and chain them effectively.

Course Orientation and Preparations

Getting Started with Express.js

Diving Deeper into Routing

Mastering Middleware

Building RESTful APIs and Integrating Databases

Securing Your Express Applications

Beyond APIs: UI Rendering, Real-Time Communication, and Logging in Express

DevConnector Project

Conclusion

Quiz: Understand and Apply Middleware in Express.js