How to correctly link providers between packages in Riverpod?

[kalaganov]

Hi Remi,

First off, I want to express my deep appreciation for your incredible work on Riverpod. I'm a big fan of this library, and it has significantly improved how I structure and manage state in my Flutter projects. Thank you for creating such a powerful and flexible tool!

I'm currently facing a challenge while working on a project with a layered architecture, and I would love to get your insights.

Context:
I have two packages: package_data_layer and package_domain_layer.

In package_data_layer, there's a repository that exposes a Stream. I'm not particularly fond of using async-await for repository interactions, so I expose the stream directly. I also created a provider that listens to this stream, which then returns AsyncValue states. I find this approach convenient for working with streams.

In package_domain_layer, I have another provider that needs to listen to the provider from package_data_layer.

Issue:
The code works perfectly when everything is in a single package. However, I'm unsure how to properly link these providers across different packages. I'm concerned that I might be missing a best practice or doing something fundamentally wrong.

Here’s a simplified version of my setup:

// ----------------- DATA LAYER
abstract interface class SomeRepo {
  Stream<String> get stream;
}

class SomeRepoImpl implements SomeRepo {
  @override
  Stream<String> get stream =>
      Stream.periodic(const Duration(seconds: 10), (i) => 'count: $i');
}

@Riverpod(keepAlive: true)
SomeRepo repo(RepoRef ref) => SomeRepoImpl();

@riverpod
AsyncValue<String> myData(MyDataRef ref) => ref.watch(repoProvider).stream;

// ----------------- DOMAIN LAYER
@riverpod
AsyncValue<String> transformedData(MyDataRef ref) {
  final asyncValue = ref.watch(myDataProvider);
  return asyncValue.when(
    data: (str) => str * 2,
    error: (_, __) => '',
    loading: () => '',
  );
}