HTTP caching headers in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set a Cache-Control header that allows caching for 1 hour.

Node.js

res.setHeader('Cache-Control', '[1]');

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

Aprivate, max-age=0

Bno-cache

Cpublic, max-age=3600

Dno-store

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'no-cache' or 'no-store' disables caching.

Forgetting to specify max-age causes no caching duration.

The Cache-Control header with public, max-age=3600 allows caching for 3600 seconds (1 hour).

2fill in blank

medium

Complete the code to set the ETag header with a unique value.

Node.js

res.setHeader('ETag', '[1]');

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

Aetag-12345

B"12345"

Cetag123

D12345

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting the ETag value causes header parsing errors.

Using non-unique ETag values defeats caching benefits.

The ETag value should be a quoted string, like "12345", to be valid.

3fill in blank

hard

Fix the error in setting the Expires header to 1 day from now.

Node.js

const expires = new Date(Date.now() + [1]).toUTCString();
res.setHeader('Expires', expires);

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

A86400000

B3600000

C60000

D1000

Attempts:

3 left

💡 Hint

Common Mistakes

Using 3600000 sets only 1 hour instead of 1 day.

Using 60000 sets only 1 minute.

86400000 milliseconds equals 1 day (24 hours * 60 minutes * 60 seconds * 1000 ms).

4fill in blank

hard

Fill both blanks to set Cache-Control for private caching and must-revalidate directive.

Node.js

res.setHeader('Cache-Control', '[1], [2]');

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

Aprivate

Bpublic

Cmust-revalidate

Dno-store

Attempts:

3 left

💡 Hint

Common Mistakes

Using public instead of private allows shared caching.

Omitting must-revalidate may cause stale content.

Setting private allows caching only for a single user, and must-revalidate forces revalidation after expiration.

5fill in blank

hard

Fill all three blanks to set Cache-Control with max-age 600 and no-transform directives.

Node.js

res.setHeader('Cache-Control', '[1]=[2], [3]');

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

Amax-age

B600

Cno-store

Dno-transform

Attempts:

3 left

💡 Hint

Common Mistakes

Using no-store with max-age is contradictory but allowed; no-store disables caching.

Forgetting to provide max-age value causes errors.

This sets max-age to 600 seconds and disables transformations on the response.