Add routes

Make your server respond to different URLs

⏱ Est. ~8 min

01 · Read

Right now your server only responds to one URL: the root path /. If you visit localhost:3000/about or localhost:3000/anything-else, you'll get an error.

Real websites have many pages — home, about, contact, product pages, and many more. Each page has its own route — a URL path the server knows how to handle.

Adding routes is how you teach your server to respond with different content for different URLs. Each app.get() call creates a new route.

💡 Picture thisThink of routes like the reception desk at an office. Someone wants the sales department, reception sends them to one room. Someone wants customer service, they go to another. Your server is the receptionist, routes are the directions.

Key points

Each app.get('/path', ...) creates a new route
The path is the part of the URL after localhost:3000
Different routes can return totally different content
This is how every website serves different pages

02 · Real-machine exercise

Open your app.js in a text editor and add these two new routes. Put them after your existing app.get('/') route, but before the app.listen() line.

app.get('/about', (req, res) => {
  res.send('This is the about page. I built this server myself!');
});

app.get('/contact', (req, res) => {
  res.send('Contact me at: hello@mysite.com');
});

03 · Real-machine exercise

Your server is still running the old code. To see the changes, you need to stop the server and restart it. Go to the terminal where the server is running, press Ctrl+C to stop it, then start it again.

node app.js

04 · Quiz

In app.get('/about', handler), what does /about represent?

The name of the file to send
The URL path that triggers this handler
A folder on the computer
A variable name

05 · Fill in the blank

In Express, app.get('/about', ...) creates a route that responds to the _____ path.

06 · Real-machine exercise

Now test your new routes! Open the browser and visit these two URLs: 1. http://localhost:3000/about — should show your about page text 2. http://localhost:3000/contact — should show your contact page text Also try http://localhost:3000 to confirm the original route still works.

http://localhost:3000/about

http://localhost:3000/contact

07 · Quiz

Your server has routes for /, /about, and /contact. A user visits http://localhost:3000/pricing. What happens?

Express automatically creates a pricing page
The server crashes with an error
The server returns a "Cannot GET /pricing" error because no route matches that path
The request gets redirected to the / route

Other lessons in this chapter

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