Why routing matters in Express - See It in Action

Why routing matters

📖 Scenario: You are building a simple web server that responds differently based on the URL path the user visits. This is like a restaurant where different doors lead to different rooms. Routing helps the server know which response to send for each door (URL).

🎯 Goal: Create an Express server with routes for the homepage, about page, and contact page. Each route should send a unique message to the browser.

📋 What You'll Learn

Create an Express app instance

Set up a route for '/' that sends 'Welcome to the homepage!'

Set up a route for '/about' that sends 'Learn more about us.'

Set up a route for '/contact' that sends 'Contact us here.'

Start the server listening on port 3000

💡 Why This Matters

🌍 Real World

Routing is how web servers decide what content to show when users visit different URLs. This is essential for websites and APIs.

💼 Career

Understanding routing is a key skill for backend developers working with Express or similar web frameworks.

1

Set up Express app

Create a variable called express that requires 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 as a function to create the app.

2

Add homepage route

Use app.get with the path '/' and a callback function with parameters req and res. Inside the callback, send the text 'Welcome to the homepage!' using res.send().

Express

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

// Add route for '/' here
// Your code here

Need a hint?

Use app.get to define a route for the homepage path '/' and send a welcome message.

3

Add about and contact routes

Add two more routes using app.get: one for '/about' that sends 'Learn more about us.', and one for '/contact' that sends 'Contact us here.'. Use req and res as parameters in the callback functions.

Express

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

app.get('/', (req, res) => {
  res.send('Welcome to the homepage!');
});

// Add routes for '/about' and '/contact' here
// Your code here

Need a hint?

Define two more routes with app.get for '/about' and '/contact' paths, sending the specified messages.

4

Start the server

Use app.listen to start the server on port 3000. Add a callback function that takes no parameters and does nothing inside.

Express

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

app.get('/', (req, res) => {
  res.send('Welcome to the homepage!');
});

app.get('/about', (req, res) => {
  res.send('Learn more about us.');
});

app.get('/contact', (req, res) => {
  res.send('Contact us here.');
});

// Start server on port 3000
// Your code here

Need a hint?

Use app.listen with port 3000 and an empty callback function to start the server.