eng(supabase): add example file (#412)

packages/brick_offline_first_with_supabase/README.md

@@ -4,6 +4,62 @@
 
 The `OfflineFirstWithSupabase` domain uses all the same configurations and annotations as `OfflineFirst`.
 
+## Repository
+
+Adding offline support to Supabase is slightly more complicated than the average [../brick_offline_first_with_rest/README.md](repository process). Feedback is welcome on a smoother and more intuitive integration.
+
+````dart
+class MyRepository extends OfflineFirstWithSupabaseRepository {
+  static late MyRepository? _singleton;
+
+  MyRepository._({
+    required super.supabaseProvider,
+    required super.sqliteProvider,
+    required super.migrations,
+    required super.offlineRequestQueue,
+    super.memoryCacheProvider,
+  });
+
+  factory MyRepository() => _singleton!;
+
+  static void configure({
+    required String supabaseUrl,
+    required String apiKey,
+    required Set<Migration> migrations,
+  }) {
+    // Convenience method `.clientQueue` makes creating the queue and client easy.
+    final (client, queue) = OfflineFirstWithSupabaseRepository.clientQueue(
+      databaseFactory: databaseFactory,
+    );
+
+    final provider = SupabaseProvider(
+      // It's important to pass the offline client to your Supabase#Client instantiation.
+      // If you're using supabase_flutter, make sure you initialize with the clientQueue's client
+      // before passing it here. For example:
+      // ```dart
+      // await Supabase.initialize(httpClient: client)
+      // SupabaseProvider(Supabase.instance.client, modelDictionary: ...)
+      // ```
+      SupabaseClient(supabaseUrl, apiKey, httpClient: client),
+      modelDictionary: supabaseModelDictionary,
+    );
+
+    // Finally, initialize the repository as normal.
+    _singleton = MyRepository._(
+      supabaseProvider: provider,
+      sqliteProvider: SqliteProvider(
+        'my_repository.sqlite',
+        databaseFactory: databaseFactory,
+        modelDictionary: sqliteModelDictionary,
+      ),
+      migrations: migrations,
+      offlineRequestQueue: queue,
+      memoryCacheProvider: MemoryCacheProvider(),
+    );
+  }
+}
+````
+
 ## Models
 
 ### ConnectOfflineFirstWithSupabase

packages/brick_supabase/example/example.dart

@@ -0,0 +1,76 @@
+import 'package:brick_core/core.dart';
+import 'package:brick_supabase/brick_supabase.dart';
+import 'package:supabase/supabase.dart';
+
+/// This class and code is always generated.
+/// It is included here as an illustration.
+/// Supabase adapters are generated by domains that utilize the brick_supabase_generators package,
+/// such as brick_offline_first_with_supabase_build
+class UserAdapter extends SupabaseAdapter<User> {
+  @override
+  Future<User> fromSupabase(data, {required provider, repository}) async {
+    return User(
+      name: data['name'],
+    );
+  }
+
+  @override
+  Future<Map<String, dynamic>> toSupabase(instance, {required provider, repository}) async {
+    return {
+      'name': instance.name,
+    };
+  }
+
+  @override
+  final defaultToNull = false;
+
+  @override
+  final fieldsToSupabaseColumns = {
+    'name': RuntimeSupabaseColumnDefinition(columnName: 'name'),
+  };
+
+  @override
+  final ignoreDuplicates = false;
+
+  @override
+  final onConflict = null;
+
+  @override
+  final tableName = 'users';
+
+  @override
+  final uniqueFields = {};
+}
+
+/// This value is always generated.
+/// It is included here as an illustration.
+/// Import it from `lib/brick/brick.g.dart` in your application.
+final dictionary = SupabaseModelDictionary({
+  User: UserAdapter(),
+});
+
+/// A model is unique to the end implementation (e.g. a Flutter app)
+class User extends SupabaseModel {
+  final String name;
+
+  User({
+    required this.name,
+  });
+}
+
+class MyRepository extends SingleProviderRepository<SupabaseModel> {
+  MyRepository(String apiUrl, String apiKey)
+      : super(
+          SupabaseProvider(
+            SupabaseClient(apiUrl, apiKey),
+            modelDictionary: dictionary,
+          ),
+        );
+}
+
+void main() async {
+  final repository = MyRepository('http://localhost:8080', 'YOUR_API_KEY_HERE');
+
+  final users = await repository.get<User>();
+  print(users);
+}