Is there a way to mutate field value inside the validator?

Hi guys!

What I'm trying to achieve is basically async validation + population of other fields based on the response's values in validator function.

So basically, I have three fields, one of them is the id. When the user enters an ID, it sends a request to the server to check if such id exists, if yes, it uses the response to populate two other fields. This behaviour seems pretty common in modern web, however I couldn't find an elegant way to implement this with final-form.

What I did seems a hacky solution for me. I stored form's initial state in the component's state and passed setState function to the validator. There if such id exists, I call setState with the response I got and then the form re-renders with updated values.

Any help much appreciated 🙂