Support for max-age Parameter in Incremental Static Regeneration (ISR)

[Strahbehry]

Goals

1. Ensure that static pages are not served stale beyond a specified maximum age.
2. Improve the freshness and reliability of served content.
3. Provide developers with more control over content lifecycle and revalidation.

Non-Goals

1. This feature does not aim to replace the existing revalidate mechanism.
2. It does not intend to handle non-static data fetching mechanisms.
3. It does not aim to introduce breaking changes to existing ISR implementations.

Background

Incremental Static Regeneration (ISR) in Next.js allows developers to revalidate static pages at specified intervals. However, this can lead to scenarios where the first user after the revalidation period receives stale data until the revalidation completes. This is particularly problematic for time-sensitive content such as news or event updates. Currently, there is no built-in mechanism to enforce a maximum age for static pages, which can result in users seeing outdated information.

Adding a max-age parameter would allow developers to specify the maximum allowable age for static content, ensuring that no user ever receives content older than a certain duration. This feature would enhance the flexibility and reliability of ISR, aligning with the goals of providing a seamless developer and user experience.

Proposal

1. API Changes:
   Extend the getStaticProps return object to accept a maxAge parameter alongside revalidate.

export async function getStaticProps() {
  const data = await fetchData();

  return {
    props: {
      data,
    },
    revalidate: 300, // Regular revalidate interval (e.g., 5 minutes)
    maxAge: 10800,   // Maximum age before forced revalidation (e.g., 3 hours)
  };
}

2. Revalidation Logic:
   Enhance the ISR mechanism to check both the revalidate interval and the maxAge value. If the page exceeds the maxAge, it should be revalidated immediately, even if it hasn't been requested by a user.

3. Background Revalidation:
   Implement background processes or hooks within Next.js to periodically check the age of static pages and trigger revalidation as needed based on the maxAge parameter.

Sadly my knowledge of the internal workings of Next JS are limited so I would not be an effective contributor.