Express.js req.baseUrl Property

The req.baseUrl property is the URL path on which a router instance was mounted. The req.baseUrl property is similar to the mount path property of the app object, except app.mountpath returns the matched path pattern(s). Syntax:

req.baseUrl

Parameter: No parameters. Returns: String Installation of express module:

1. You can visit the link to Install express module. You can install this package by using this command.

npm install express

1. After installing the express module, you can check your express version in command prompt using the command.

npm version express

1. After that, you can just create a folder and add a file for example, index.js. To run this file you need to run the following command.

node index.js

Example 1: Filename: index.js

javascript

var express = require('express');
var app = express();
var PORT = 3000;

var user = express.Router();

user.get('/login', function (req, res) {
  console.log(req.baseUrl);
  res.end();
})

app.use('/user', user);

app.listen(PORT, function(err){
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});

Steps to run the program:

1. The project structure will look like this:
2. Make sure you have installed express module using the following command:

npm install express

1. Run index.js file using below command:

node index.js

1. Output:

Server listening on PORT 3000

1. Now open your browser and go to http://localhost:3000/user/login, now you can see the following output on your console:

Server listening on PORT 3000
/user

Example 2: Filename: index.js

javascript

var express = require('express');
const e = require('express');
var app = express();
var PORT = 3000;

var student = express.Router();
app.use('/student', student);

student.get('/signup', function (req, res) {
    if(req.baseUrl == '/student')
    {
        console.log("Show Signup Form");
        res.end();
    } else {
        console.log("Invalid Request")
        res.send("Invalid Route")
    }
})

app.listen(PORT, function(err){
    if (err) console.log(err);
    console.log("Server listening on PORT", PORT);
});

Run index.js file using below command:

node index.js

Output: Now open your browser and make GET request to http://localhost:3000/student/signup, now you can see the following output on your console:

Show Signup Form

Reference: https://expressjs.com/en/4x/api.html#req.baseUrl