Providers

app/providers.dart is the only file that constructs ServerpodBookRepository.

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Riverpod providers are the composition root. They are written by hand. There is no @riverpod annotation and no build_runner step for them. build_runner in this app is only for dart_mappable.

Create lib/app/providers.dart. clientProvider throws until main overrides it, so a test that forgets the override fails immediately instead of opening a socket:

dart

import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:shelf_client/shelf_client.dart';
import 'package:shelf_flutter/application/book/list_books_use_case.dart';
import 'package:shelf_flutter/application/book/save_book_use_case.dart';
import 'package:shelf_flutter/application/ports/clock.dart';
import 'package:shelf_flutter/application/ports/id_generator.dart';
import 'package:shelf_flutter/data/serverpod_book_repository.dart';
import 'package:shelf_flutter/domain/book/book_repository.dart';

/// Overridden in main with the generated client.
final clientProvider = Provider<Client>((ref) {
  throw StateError('Override clientProvider in main');
});

final bookRepositoryProvider = Provider<BookRepository>((ref) {
  return ServerpodBookRepository(ref.watch(clientProvider));
});

final clockProvider = Provider<Clock>((ref) => const SystemClock());

final idGeneratorProvider = Provider<IdGenerator>(
  (ref) => const UuidIdGenerator(),
);

final saveBookUseCaseProvider = Provider<SaveBookUseCase>((ref) {
  return SaveBookUseCase(
    ref.watch(bookRepositoryProvider),
    clock: ref.watch(clockProvider),
    ids: ref.watch(idGeneratorProvider),
  );
});

final listBooksUseCaseProvider = Provider<ListBooksUseCase>((ref) {
  return ListBooksUseCase(ref.watch(bookRepositoryProvider));
});

The provider's type is BookRepository, not ServerpodBookRepository. A widget test overrides bookRepositoryProvider with an in-memory fake and never constructs a Client.

Shelf providers (shelfRepositoryProvider, saveShelfUseCaseProvider, listShelvesUseCaseProvider, placeBookOnShelfUseCaseProvider) go in this same file when you add those classes. placeBookOnShelfUseCaseProvider watches bookRepositoryProvider, because the client use case takes the book port. It does not watch a shelf repository. The server is the place that takes both.

Next: the books screen.