swrly_hooks #

Flutter Hooks bindings for swrly. useSwrlyQuery + useSwrlyMutation for consuming a swrly cache from HookWidget-based screens — with correct subscriber lifecycle, canonical key hashing and proper unhandled-async handling out of the box.

Why is this a separate package? #

The core swrly package intentionally does not depend on flutter_hooks — users who don't reach for hooks shouldn't pay for the dep. This companion package (mirroring the flutter_riverpod / hooks_riverpod split) is the officially supported path when you do use hooks.

Rolling your own useSwrlyQuery off Query.stream looks like a one-liner but has three subtleties that regularly bite:

• useStream(query.stream) does NOT register a swrly subscriber — so invalidate() will not refetch and the entry may cacheTime-GC while your widget is still mounted.
• query.fetch() returns a Future — discarding it makes the terminal retry failure an unhandled async error, even though the emitted QueryState.error renders fine.
• query.key.toString() collides across distinct keys (['a, b'] vs ['a', 'b'] both stringify as [a, b]), so an effect keyed on that string can silently stop refetching on key changes.

swrly_hooks handles all three.

Install #

flutter pub add swrly swrly_hooks

Use #

import 'package:flutter_hooks/flutter_hooks.dart';
import 'package:swrly/swrly.dart';
import 'package:swrly_hooks/swrly_hooks.dart';

final postsQuery = Query<List<Post>>(
  key: const ['posts'],
  fn: () => api.getPosts(),
  staleTime: const Duration(seconds: 30),
);

class PostsPage extends HookWidget {
  const PostsPage({super.key});

  @override
  Widget build(BuildContext context) {
    final state = useSwrlyQuery(postsQuery);
    if (state.isLoading && !state.hasData) {
      return const CircularProgressIndicator();
    }
    if (state.isError && !state.hasData) {
      return Text('${state.error}');
    }
    return PostsView(state.data!);
  }
}

For mutations:

class CreatePostButton extends HookWidget {
  const CreatePostButton({super.key});

  @override
  Widget build(BuildContext context) {
    final mut = useSwrlyMutation<Post, String>(api.createPost);
    return FilledButton(
      onPressed: mut.state.isLoading
          ? null
          : () async {
              await mut.mutate('Hello');
              postsQuery.invalidate();
            },
      child: Text(mut.state.isLoading ? 'Saving…' : 'Save'),
    );
  }
}

For optimistic writes with automatic rollback (onMutate returning a rollback closure, onSuccess/onSettled callbacks that fire regardless of mount state), prefer swrly's built-in MutationBuilder — this hook is intentionally minimal.

License #

MIT