Note: The documentation says we can bypass middleware functions following the current one by calling next('route') within the current middleware function, but this technique didn't work for me within app.use but did work with app.METHOD like below. Next() fn needs to be called within each middleware function when multiple middleware functions are passed to app.use, else the next middleware function won’t be called. To give an example for conceptual understanding of Express Middleware, here is what my app middleware stack (app.stack) looks like when logging my app object to the console as JSON: stack: Middleware layers can be added one by one in multiple invocations of use, or even all at once in series with one invocation. Let's learn Express.js in 15 minutes Show more Show more Learn Express.js In 48. To setup your middleware, you can invoke app.use() for every middleware layer that you want to add (it can be generic to all paths, or triggered only on specific path(s) your server handles), and it will add onto your Express middleware stack. Express JS is an awesome opinionated framework for Node.js that helps you create REST end points.

It has a middleware stack that can be customized in app.configure()(this is now deprecated in version 4.x). The app object is instantiated on creation of the Express server.

Express javascript