On-demand revalidation in NextJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is on-demand revalidation in Next.js?

On-demand revalidation lets you update a static page after it's built, without rebuilding the whole site. You ask Next.js to refresh the page data when something changes.

beginner

Which Next.js function is used to trigger on-demand revalidation?

You use the res.revalidate(path) method inside an API route to tell Next.js to update the static page at the given path.

intermediate

Why use on-demand revalidation instead of rebuilding the whole site?

It saves time and resources by updating only the changed pages, so your site stays fast and fresh without full rebuilds.

beginner

What is a common use case for on-demand revalidation?

When content changes in a CMS or database, you can call on-demand revalidation to update the affected pages immediately.

intermediate

How do you secure an API route that triggers on-demand revalidation?

You add a secret token check in the API route to allow only authorized requests to trigger revalidation.

What does res.revalidate('/path') do in Next.js?

A Disables static generation for '/path'

B Deletes the static page at '/path'

C Triggers a rebuild of the entire site

D Updates the static page at '/path' with fresh data

The res.revalidate('/path') method tells Next.js to regenerate the static page at '/path' with updated data.

Where do you typically call on-demand revalidation in Next.js?

A Inside an API route handler

B Inside getStaticProps

C Inside the _app.js file

D Inside the page component's render method

On-demand revalidation is triggered inside an API route handler where you can call res.revalidate().

Which of these is NOT a benefit of on-demand revalidation?

A Faster updates for changed pages

B Full site rebuild on every content change

C Reduced server load compared to full rebuilds

D Better user experience with fresh content

On-demand revalidation avoids full site rebuilds, so option C is not a benefit.

How can you protect your on-demand revalidation API route?

A By using a secret token check

B By disabling API routes

C By calling revalidate only in getStaticProps

D By using client-side JavaScript only

Adding a secret token check ensures only authorized requests can trigger revalidation.

When is on-demand revalidation most useful?

A When you want to rebuild the entire site daily

B When you want to disable static generation

C When content changes frequently and you want fast updates

D When you never update your site content

On-demand revalidation is great for fast updates when content changes often.

Explain how on-demand revalidation works in Next.js and why it is useful.

Think about how you can refresh a page after it is built without rebuilding the whole site.

Describe how to secure an API route that triggers on-demand revalidation in Next.js.

Consider how to prevent unauthorized users from forcing page updates.