Express.js Routing

Routing is made from the word route. It is used to determine the specific behavior of an application. It specifies how an application responds to a client request to a particular route, URI or path and a specific HTTP request method (GET, POST, etc.). It can handle different types of HTTP requests.

Let's take an example to see basic routing.

File: routing_example.js

1. var express = require('express');  
2. var app = express();  
3. app.get('/', function (req, res) {  
4.    console.log("Got a GET request for the homepage");  
5.    res.send('Welcome to JavaTpoint!');  
6. })  
7. app.post('/', function (req, res) {  
8.    console.log("Got a POST request for the homepage");  
9.    res.send('I am Impossible! ');  
10. })  
11. app.delete('/del_student', function (req, res) {  
12.    console.log("Got a DELETE request for /del_student");  
13.    res.send('I am Deleted!');  
14. })  
15. app.get('/enrolled_student', function (req, res) {  
16.    console.log("Got a GET request for /enrolled_student");  
17.    res.send('I am an enrolled student.');  
18. })  
19. // This responds a GET request for abcd, abxcd, ab123cd, and so on  
20. app.get('/ab*cd', function(req, res) {     
21.    console.log("Got a GET request for /ab*cd");  
22.    res.send('Pattern Matched.');  
23. })  
24. var server = app.listen(8000, function () {  
25. var host = server.address().address  
26.   var port = server.address().port  
27. console.log("Example app listening at http://%s:%s", host, port)  
28. })  

You see that server is listening.

Now, you can see the result generated by server on the local host http://127.0.0.1:8000

Output:

This is the homepage of the example app.

Note: The Command Prompt will be updated after one successful response.

You can see the different pages by changing routes. http://127.0.0.1:8000/enrolled_student

Updated command prompt:

This can read the pattern like abcd, abxcd, ab123cd, and so on.

Next route http://127.0.0.1:8000/abcd

Next route http://127.0.0.1:8000/ab12345cd

Updated command prompt: