Express is a common way to display static routes to a user. It is even more commonly used to create APIs for Node.JS. In Express, it's easy to define a URL and what will happen at that URL. We can also define middleware, which runs before the final request is returned. This can let us to alter the request and do it in a standard way across many routes.
If you've used Express, you may have already used pre-built middleware like bodyParser or jsonParser. In this guide, let's look at how you can create your own custom middleware.