Node.js, MongoDB, and AngularJS Web Development

Creating Custom Middleware

With Express, you can create your own middleware. All you need to do is provide a function that accepts the Request object as the first parameter, the Response object as the second parameter, and next as the third parameter. The next parameter is a function passed by the middleware framework that points to the next middleware function to execute, so you must call next() prior to exiting your custom function, or the handler will never be called.

To illustrate how easy it is to implement your own custom middleware functionality in Express, Listing 19.10 implements a middleware function named queryRemover() that strips the query string off the URL before sending it on to the handler.

Notice that queryRemover() accepts ...