Determine when using cached response (onSuccess is not called when cache is used)

[calengbuford]

When successfully fetching a new response, the onSuccess function is called. However, when using the cached response instead, onSuccess is not called. This means if I want to send analytics (or do anything else) upon a successful data change, I can't do that with onSuccess.

It would be great to have a new function that tells me when the cache is used or that tells me when the data is updated. A useEffect to manually do this can be costly for performance.

[TkDodo]

A useEffect to manually do this can be costly for performance.

why? A useEffect with data as dependency does exactly what you want - being executed whenever data changes.

For v4, we thought about an extra callback onDataChanged, but it's not a very common use-case and can easily be done with an effect in userland. Also documented this in v4.