Revalidation Basics

This page perfoms a fetch on the server to get a random article from Wikipedia. The fetched data is then cached with a tag named "randomWiki" and a maximum age of 60 seconds.

const url = 'https://en.wikipedia.org/api/rest_v1/page/random/summary';

async function RandomArticleComponent() {
const randomArticle = await fetch(url, {
next: { revalidate: 60, tags: ['randomWiki'] }
});
// ...render
}

After the set time has passed, the first request for this page would trigger its rebuild in the background. When the new page is ready, subsequent requests would return the new page - see stale-white-revalidate.

Alternatively, if the cache tag is explicitly invalidated by revalidateTag('randomWiki'), any page using that tag would be rebuilt in the background when requested.

In real-life applications, tags are typically invalidated when data has changed in an external system (e.g., the CMS notifies the site about content changes via a webhook), or after a data mutation made through the site.

For this functionality to work, Next.js uses the fine-grained caching headers available on Netlify - but you can use these features on basically any Netlify site!

Lunar Saros 124
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Saros cycle series 124 for lunar eclipses occurs at the moon's ascending node, 18 years 11 and 1/3 days. It contains 73 member events, with 28 total eclipses, starting in 1657 and ending in 2144. The [...]

From Wikipedia