[Feature Request] More control on cache provider

[zluo01]

Hi,

I notice for SWR, it only supports provide cache source directly by providing a storage instance.

However, I have a use case that I wanna use SWR in a web extension. Since in web extension, all requests are actually being made from the background scripts, using SWR would not do any thing as every time when opening the pop up, it will act like a new page load. Thus, I have to create some storage/cache instance on the backend script end to cache responses and at the same time, I would like to utilize the invalidation from SWR to handle any actions and updates. Hence, would like to ask for a way to utilize some storage through functions instead of the storage directly.

i.e. instead of directly provide new Map(), we can have something liike

{
 save: (key, value) => void,
get:  (key) => void,
invalidate: (key) => void
}

since there is no direct way to get the storage from the background script on frontend.

I am not sure if it is supported by someway or not, or there is other better way to solve this problem.

Thanks.