How to handle 404 error in express ?

404 error in a service is typically used to denote that the requested resource is not available. In this article we will see how to handle 404 error in express. Once express gets a request, it looks for matching middleware or routes. If it can’t find a match for the request, then it throws a 404 error.

To handle a 404 error in express, we need to write a middleware function at the bottom stack. Take a look at the below example.

var express = require("express");
var app = express();
//Express GET call
app.get('/calculate',function(req,res){
	res.send("Example GET");
});

//Capture All 404 errors
app.use(function (req,res,next){
	res.status(404).send('Unable to find the requested resource!');
});

app.listen(8080);