req.ip and req.hostname in Express - Mini Project: Build & Apply

Using req.ip and req.hostname in Express

📖 Scenario: You are building a simple Express server that logs and shows the visitor's IP address and the hostname they used to access your site. This helps you understand where your visitors come from and which domain they used.

🎯 Goal: Create an Express server with a route that reads the visitor's IP address using req.ip and the hostname using req.hostname. Then send a response showing these values.

📋 What You'll Learn

Create an Express app

Add a route for GET requests to '/'

Use req.ip to get the visitor's IP address

Use req.hostname to get the hostname

Send a response that includes both the IP and hostname

💡 Why This Matters

🌍 Real World

Web servers often need to know the visitor's IP and hostname to customize responses, log traffic, or apply security rules.

💼 Career

Understanding how to access request details like IP and hostname is essential for backend developers working with Express or similar web frameworks.

1

Set up Express app

Create a variable called express by requiring the 'express' module. Then create a variable called app by calling express().

Express

const express = require('express');
const app = express();
// Your code here

Need a hint?

Use require('express') to import Express and then call it to create your app.

2

Add a GET route for '/'

Add a GET route on app for path '/' with a callback function that takes req and res as parameters.

Express

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  // Your code here
});

Need a hint?

Use app.get with the path '/' and a function with req and res.

3

Get visitor IP and hostname

Inside the GET route callback, create two variables: visitorIp set to req.ip and visitorHost set to req.hostname.

Express

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  // Your code here
});

Need a hint?

Use req.ip to get the IP and req.hostname to get the hostname.

4

Send response with IP and hostname

Still inside the GET route callback, send a response using res.send that includes the text: `Your IP is ${visitorIp} and your hostname is ${visitorHost}`.

Express

const express = require('express');
const app = express();

app.get('/', (req, res) => {
  const visitorIp = req.ip;
  const visitorHost = req.hostname;
  // Your code here
});

Need a hint?

Use a template string inside res.send to include the variables.