Courses / Node.js
10. Middleware signature and ordering
Understand middleware function shape (req, res, next) and how execution order affects request handling.
JavaScript
Middleware signature and ordering
Functions with the shape (req, res, next) run in sequence and control whether a request keeps flowing or stops.
"I need some shared logic (auth, logging) to run for many routes without duplicating code."
Middleware are functions that receive (req, res, next) and either call next() to pass control or end the response; their order determines which runs first and whether later middleware runs at all.
"I need some shared logic (auth, logging) to run for many routes without duplicating code."
Middleware are functions that receive (req, res, next) and either call next() to pass control or end the response; their order determines which runs first and whether later middleware runs at all.