Is lazy evaluation possible for a query key

[vmichailidisdev]

Hello,
So, I want to fetch something but I only know the key that will be assigned to the cache after the fetch is finished.

The only way I can think is:

fetch(url).then(data => queryClient.setQueryData(createKeyFrom(data), data))

Is there any cleaner way of doing this? (I don't mind having the same data under 2 query keys.)

[TkDodo]

but I only know the key that will be assigned to the cache after the fetch is finished.

how is that possible? The key is the dependency to the fetch ...

[TkDodo]

So, we cannot leverage the already fetched data

that's right, but I don't know how / why "changing" the queryKey would be a solution to this problem. I would maybe pre-fill the ['conversations', userId] cache with data from the ['conversations', conversationId] cache if it exists. For example, we can call queryClient.getQueriesData(['conversations']) to get all conversations and then loop through them to see if there is one that matches our conversationId. This can be one in initialData, and if we don't have any, the queryFn will just run as usual...

[vmichailidisdev]

Thank you very much for the suggestion. It will fit just fine.

[vmichailidisdev]

What about listening to cache events and when data with this specific query key are added, add the data under another query key?

[TkDodo]

sure, you can do queryClient.getQueryCache().subscribe and listen to all events that come in and do with those what you like. That's also what the devtools do :)