Livereload stops working after ~20s for data imported through `getStaticProps`

[schickling]

What version of Next.js are you using?

12

What version of Node.js are you using?

Confirmed with v14 and v16 (probably in others as well)

What browser are you using?

Confirmed with Chrome and Safari

What operating system are you using?

macOS

How are you deploying your application?

Describe the Bug

It seems that Next.js' livereload stops working after ~20s for data imported through getStaticProps.

Here is an explainer video:

CleanShot.2022-02-07.at.12.27.37.mp4

Expected Behavior

Livereload should keep working

To Reproduce

Open this project on Stackblitz: https://stackblitz.com/edit/nextjs-bmc4oy?file=pages%2Findex.js

[balazsorban44]

Hi, this is because, by default, the Next.js dev server will get rid of entries outside of the watch period. This is 15 seconds by default:

next.js/packages/next/server/config-shared.ts

Line 422 in c051af8

maxInactiveAge: 15 * 1000,

You can configure this to be a higher value by the onDemandEntries option in next.config.js.

https://nextjs.org/docs/api-reference/next.config.js/configuring-onDemandEntries

[balazsorban44]

Additional comment, we are looking into ways to make onDemandEntries unnecessary.

[schickling]

Thanks for this additional context @balazsorban44.

we are looking into ways to make onDemandEntries unnecessary.

Is there an issue for this already?

[balazsorban44]

I don't think there is a specific issue created for it, I would say it's borderline a feature request anyway.

I'll try to keep in mind and notify you when this has advanced. 👍

[balazsorban44]

After some internal discussion, we could consider this as a bug after all, as it might be an unexpected behavior so I'll reopen for tracking.