beginner

Express Middleware example 65

A focused ExpressJS example for express middleware with output and explanation.

Express Middleware example 65
lesson.js
1
2
3
4
javascript4 linesWrap
Input

Terminal

Success

Ready.

Run code to see output here.

What this example teaches

Express Middleware

Output

Express server listens on port 3000 and returns a JSON response on matched routes.

Line-by-line explanation

  • Line 1 sets up the Express Middleware example: app.use((req, res, next) => {.
  • Line 2 exposes the output so you can verify the behavior: console.log(`[${new Date().toISOString()}] ${req.method} ${req.url}`);.
  • Line 3 adds one required part of the working pattern: next();.
  • Line 4 adds one required part of the working pattern: });.

Why this example is useful

This example is useful because it isolates express middleware without surrounding noise, so you can see the idea clearly.

Where it is used in real projects

Express Middleware appears in real ExpressJS work when a feature needs a clear pattern that can be reviewed and changed safely.

Beginner variation

Change one label, value or condition in the Express Middleware example and run it again.

Advanced variation

Combine Express Middleware with validation, error handling or reusable structure.