Backend with Node.js

🛡️ Middleware in Express

Intermediate functions (middleware): how they chain together, when they call next() and when they stop the request.

What you'll learn

• Implement middleware with the (req, res, next) signature and decide between calling next() or responding
• Chain global middleware (app.use) and per-route middleware in the correct order
• Stop the request with the appropriate response (401 without authorization, 400 for invalid data)
• Enrich the req object with data for the following middleware and handlers

Lessons