Top 10 Ways to Master ExpressJS Middleware in Node.js

"In the world of backend development, Express.js middleware is a core concept that every developer must understand. Middleware functions in Express.js are essential for handling requests, responses, and adding modular, reusable functionality to applications.

In this guide, we’ll explore what middleware is, how it works in Express.js, why it’s so powerful, and how to implement it effectively with 10 practical examples. Whether you’re a beginner or an intermediate developer, this article will give you a complete understanding of Express.js middleware.

ExpressJS Middleware: What It Is
Middleware in Express.js refers to functions that execute during the request-response cycle. These functions have access to the request object (req), the response object (res), and the next() function that triggers the next middleware.

Middleware functions are the perfect place to modify the req and res objects with relevant information. For instance, after a user has logged in, you could fetch their user details from a database, and then store those details in res.user."