Why REST principles matter in Express - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a basic Express server that listens on port 3000.

Express

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

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen([1], () => {
  console.log('Server is running');
});

Drag options to blanks, or click blank then click option'

A80

B3000

C5000

D8080

Attempts:

3 left

💡 Hint

Common Mistakes

Using a port number that is already in use or reserved.

Forgetting to pass a number as the port.

The server listens on port 3000, which is a common default port for Express apps.

2fill in blank

medium

Complete the code to parse incoming JSON request bodies in Express.

Express

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

app.use([1]());

app.post('/data', (req, res) => {
  res.json(req.body);
});

Drag options to blanks, or click blank then click option'

Aexpress.static

Bexpress.urlencoded

Cexpress.json

Dexpress.raw

Attempts:

3 left

💡 Hint

Common Mistakes

Using express.urlencoded() which parses URL-encoded data, not JSON.

Forgetting to use any body parsing middleware.

express.json() middleware parses JSON request bodies so you can access them via req.body.

3fill in blank

hard

Fix the error in the route handler to correctly send a 404 status when a resource is not found.

Express

app.get('/item/:id', (req, res) => {
  const item = database.find(i => i.id === req.params.id);
  if (!item) {
    res.status([1]).send('Not Found');
  } else {
    res.json(item);
  }
});

Drag options to blanks, or click blank then click option'

A404

B200

C500

D301

Attempts:

3 left

💡 Hint

Common Mistakes

Using 200 which means success even when the item is missing.

Using 500 which means server error, not client error.

HTTP status 404 means the requested resource was not found, which is appropriate here.

4fill in blank

hard

Fill both blanks to create a RESTful route that updates an item by ID using the correct HTTP method and URL pattern.

Express

app.[1]('/items/[2]', (req, res) => {
  // update item logic here
  res.send('Item updated');
});

Drag options to blanks, or click blank then click option'

Aput

Bpost

Cpatch

D:id

Attempts:

3 left

💡 Hint

Common Mistakes

Using POST which is for creating resources.

Omitting the ID parameter in the URL.

PUT is the HTTP method used to update a resource fully, and ':id' is the URL parameter for the item identifier.

5fill in blank

hard

Fill all three blanks to create a RESTful Express route that deletes an item by ID and sends a 204 status code.

Express

app.[1]('/items/[2]', (req, res) => {
  // delete item logic
  res.status([3]).send();
});

Drag options to blanks, or click blank then click option'

Adelete

B:itemId

C204

D200

Attempts:

3 left

💡 Hint

Common Mistakes

Using 200 status code which usually includes a response body.

Using POST or PUT instead of DELETE.

DELETE is the HTTP method to remove a resource, ':itemId' is the URL parameter, and 204 means No Content, indicating successful deletion without response body.