Asynchronous fromJson and toJson

[felangel]

@saivarunr:

Greetings @felangel , hope you are healthy and safe. I would also like to thank you for the libraries you have provided to the community. I'm using bloc and hydrated bloc. I was thinking why not provide async support for both fromJson and toJson on the HydratedBloc (

hydrated_bloc/lib/src/hydrated_bloc.dart

Line 37 in 15eb68f

return _state = fromJson(Map<String, dynamic>.from(stateJson));
)
Describe the solution you'd like
I have this use case where we have to perform compute, validate checksum and then consider the input from local cache for further processing. At first, glance looks like it is not possible to invoke async methods/functions inside fromJson. If it cannot be implemented due to the underlying API, how do you suggest I should handle this problem on my side?

[felangel]

Closing this for now because to/from json must be synchronous based on the current API specification.

[inveker]

If you are satisfied that the initial state will be the default, and the restored state will be set via an event, you can use this code

 @override
 State? fromJson(Map<String, dynamic> json) {
   Future(() => add(RestoreEvent(json)));
 }
  
 Future<void> _restore(RestoreEvent event, Emitter<State> emit) async {
   final json = event.json;
   emit(State(...));
 }