Express: Catch `404` errors

README.md

Express: Catch 404 Not Found errors

Prerequisites

1. Express "Hello World!" app created.

Instructions

1. Create a Hello World! express app or use an existing express project.

2. Add support for 404 error handling. Add this custom middleware function after all other middleware that sends a request:

   app.use(function(request, response) {
     response.status(404);
     response.send('404: File Not Found');
   });

   • It's important this is the last middleware in your file just before the server is started. This function always returns a 404 response when it's invoked. In other words, if the request hasn't been sent by the time it reaches this function, it's a 404 by process of elimination.

Related Gists

• Express: Serving static files