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RiverPod - How to await using FutureProvider on AsyncValue not in widget


I need to get 1 field 1 time from Firebase Cloud Firestore. How do I accomplish this with providers outside of Widget build?

Below are my combined providers. appStartupProvider is a FutureProvider and I want to get the bool value from this 1 field in firestore. However, the await in appStartupProvider states "'await' applied to 'AsyncValue', which is not a 'Future'".

final accountStreamProvider = StreamProvider<Account>((ref) {
  final database = ref.watch(databaseProvider);
  return database != null ? database.accountStream() : const Stream.empty();
});

final _accountSetupCompleteProvider = Provider<AsyncValue<bool>>((ref) {
  return ref
      .watch(accountStreamProvider)
      .whenData((account) => account?.accountSetupComplete ?? false);
});

final appStartupProvider = FutureProvider<bool>((ref) async {
  final accountSetupComplete = await ref.watch(_accountSetupCompleteProvider);

  return accountSetupComplete;
});

Obviously missing some key knowledge here on combing providers and AsyncValue, but I'm trying to accomplish the situation stated on RiverPod Combining Providers page, where I see await is being used.

enter image description here


Solution

  • The example in the documentation was incorrect at the time of your post. It has since been updated and is now correct.

    This is how you could write it:

    final accountStreamProvider = StreamProvider<Account?>((ref) {
      final database = ref.watch(databaseProvider);
      return database != null ? database.accountStream() : const Stream.empty();
    });
    
    final _accountSetupCompleteProvider = FutureProvider<bool>((ref) async {
      final account = await ref.watch(accountStreamProvider.last);
      return account?.accountSetupComplete ?? false;
    });
    
    final appStartupProvider = FutureProvider<bool>((ref) async {
      final accountSetupComplete = await ref.watch(_accountSetupCompleteProvider.future);
      return accountSetupComplete;
    });
    

    Or:

    final accountStreamProvider = StreamProvider<Account?>((ref) {
      final database = ref.watch(databaseProvider);
      return database != null ? database.accountStream() : const Stream.empty();
    });
    
    final _accountSetupCompleteProvider = Provider<AsyncValue<bool>>((ref) {
      return ref
          .watch(accountStreamProvider)
          .whenData((account) => account?.accountSetupComplete ?? false);
    });
    
    final appStartupProvider = Provider<bool>((ref) {
      final accountSetupComplete = ref.watch(_accountSetupCompleteProvider).maybeWhen(
            data: (data) => data, 
            orElse: () => false,
          );
    
      return accountSetupComplete;
    });