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Server

We're building a fully-fledged web server from scratch on your local machine. The test suite will make HTTP requests to your local server over localhost. Your server will run in one terminal, while you submit tests with the Boot.dev CLI in another terminal.

Express

Express makes it easy to build a simple server in Node.js. Calling express() creates an application that can receive HTTP requests. Because the application won't have any routes yet, it will respond to every request with 404 Not Found.

Start the server by calling the application's .listen() method with the port on which it should listen for incoming requests.

Documentation

Being a programmer means reading documentation and searching for examples. We're already telling you everything you need to know to build Chirpy, but we don't want to rob you of valuable practice reading the docs and learning from examples. Read Express's Hello World example as a primer.

Reading documentation is an essential skill because a professional in any field should never stop learning. In fact, the best way to learn is on the clock.

Assignment

Build and run a server that listens on port 8080 and responds to every request with 404 Not Found.

Install Express and its TypeScript definitions:

npm install express
npm install -D @types/express

Delete the Hello World code in src/index.ts and replace it with your server.
Create an Express application.
Start the server by calling .listen() with port 8080.
Build and run the server with npm run dev. You'll need to do this each time you change your code.
Open http://localhost:8080 in your browser. You should see Cannot GET / because the application doesn't have any routes yet. Don't worry, that's expected right now!

In another terminal window, while your server is still running, run and submit the CLI tests.

Tip

If the bootdev CLI requests a URL other than localhost:8080, your ~/.bootdev.yaml file may have the base_url set from a different course. Run bootdev config base_url --reset before running the tests again.