long poll for prefetching

[andrewnaeve]

For a normal query, to long poll I set the refetchInterval. However, this option is not available for prefetching. If I receive a response from my prefetch that indicates I want to check the server again, how do I do that?

[TkDodo]

I don't think that's what prefetching is about. If you get a response from prefetching that indicates that you should check the server again, that response is put into the cache for react-query. As soon as you call useQuery for that key (which will probably be quite soon after prefetching has happened), you'll have access to that data and can create a conditional refetchInterval with:

refetchInterval: (data) => // return a number based on data

this will work no matter how data got into the cache.

[andrewnaeve]

Thank you for the reply, I also did not know that refetchInterval took a callback. My use-case is that I have up to 20+ large reports in a tab browser, that are pre-fetched so that the user already has the report when they click on the tab. However, there is a "download all" button that assumes all reports are either fully fetched, or in process of being fetched. Would you opt for useQueries then for this?

[TkDodo]

probably