Merge pull request #19 from olmps/architecture-updates

Architecture updates

Author: matuella

.resources/00arch_overview.png

@@ -8,7 +8,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 Releases here should only be made whenever there is a build available for them in the respective stores (even if it's
 a beta or production release, they must be documented here).
 
-## Unreleased
+## [Unreleased]
 
 > Android build: ?
-> iOS build: ?
+> iOS build: ?
+
+## [0.1.0-dev.1] - 2021-04-01
+
+Initial release, defines core architecture.
+The application is unusable on this version.

.resources/00arch_overview_simple.png

@@ -1,7 +1,9 @@
 import 'package:flutter/foundation.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
-import 'package:memo/data/database_repository.dart';
-import 'package:memo/data/sembast_database.dart' as sembast_db;
+import 'package:memo/data/repositories/deck_repository.dart';
+import 'package:memo/domain/services/deck_services.dart';
+import 'package:memo/data/gateways/document_database_gateway.dart';
+import 'package:memo/data/gateways/sembast_database.dart' as sembast_db;
 import 'package:sembast/sembast.dart';
 
 /// Manages all app asynchronous dependencies
@@ -41,14 +43,16 @@ class AppVMImpl extends AppVM {
     //
     // All of these needs a late initialization due to runtime dependencies, which we will only know after some async
     // initialization.
-    final dbRepo = DatabaseRepositoryImpl(dependencies[0] as Database);
-    // final exampleServices = HabitsServicesImpl(dbRepo: dbRepo);
-    // return AppState(exampleServices: exampleServices);
-    value = AsyncValue.data(AppState());
+
+    final dbRepo = SembastGateway(dependencies[0] as Database);
+    final decksRepo = DeckRepositoryImpl(dbRepo);
+    final deckServices = DeckServicesImpl(decksRepo);
+
+    value = AsyncValue.data(AppState(deckServices: deckServices));
   }
 }
 
 class AppState {
-  // const AppState({required this.exampleServices});
-  // final ExampleServices exampleServices;
+  const AppState({required this.deckServices});
+  final DeckServices deckServices;
 }

.resources/01arch_overview_complex.png

@@ -0,0 +1,90 @@
+import 'dart:async';
+import 'package:sembast/sembast.dart';
+
+/// Handles the local persistence to the database
+abstract class DocumentDatabaseGateway {
+  /// Adds an [object] to the [store], using a [id]
+  ///
+  /// If there is already an object with the same [id], the default behavior is to merge all of its fields.
+  /// [shouldMerge] should be `false` if pre-existing fields should not be merged.
+  Future<void> put({
+    required String id,
+    required Map<String, dynamic> object,
+    required String store,
+    bool shouldMerge = true,
+  });
+
+  /// Deletes the value with [id] from the [store]
+  Future<void> remove({required String id, required String store});
+
+  /// Retrieves an object with [id] from the [store]
+  ///
+  /// Returns `null` if the key doesn't exist
+  Future<Map<String, dynamic>?> get({required String id, required String store});
+
+  /// Retrieves all objects within [store]
+  Future<List<Map<String, dynamic>>> getAll({required String store});
+
+  /// Retrieves a stream of all the [store] objects, triggered whenever any update occurs to this [store]
+  Future<Stream<List<Map<String, dynamic>>>> listenAll({required String store});
+}
+
+//
+// DocumentDatabaseGateway implementation using `sembast`
+//
+class SembastGateway implements DocumentDatabaseGateway {
+  SembastGateway(this._db);
+
+  // `sembast` database instance
+  final Database _db;
+
+  @override
+  Future<void> put({
+    required String id,
+    required Map<String, dynamic> object,
+    required String store,
+    bool shouldMerge = true,
+  }) async {
+    final storeMap = stringMapStoreFactory.store(store);
+
+    await storeMap.record(id).put(_db, object, merge: shouldMerge);
+  }
+
+  @override
+  Future<void> remove({required String id, required String store}) async {
+    final storeMap = stringMapStoreFactory.store(store);
+    await storeMap.record(id).delete(_db);
+  }
+
+  @override
+  Future<Map<String, dynamic>?> get({required String id, required String store}) async {
+    final storeMap = stringMapStoreFactory.store(store);
+    return storeMap.record(id).get(_db);
+  }
+
+  @override
+  Future<List<Map<String, dynamic>>> getAll({
+    required String store,
+  }) async {
+    final storeMap = stringMapStoreFactory.store(store);
+
+    final allRecords = await storeMap.find(_db);
+    return allRecords.map((record) => record.value).toList();
+  }
+
+  @override
+  Future<Stream<List<Map<String, dynamic>>>> listenAll({required String store}) async {
+    final storeMap = stringMapStoreFactory.store(store);
+
+    return storeMap.query().onSnapshots(_db).transform(snapshotTransformer);
+  }
+
+  /// Transforms a list of `sembast` snapshot records into a list of objects
+  final snapshotTransformer =
+      StreamTransformer<List<RecordSnapshot<String, Map<String, Object?>>>, List<Map<String, Object?>>>.fromHandlers(
+    handleData: (snapshots, sink) {
+      final transformedRecords = snapshots.map((record) => record.value).toList();
+      sink.add(transformedRecords);
+    },
+  );
+}

ARCHITECTURE.md

@@ -1,6 +1,6 @@
 import 'dart:async';
 
-import 'package:flutter/foundation.dart';
+import 'package:meta/meta.dart';
 import 'package:path/path.dart' as path;
 import 'package:path_provider/path_provider.dart';
 import 'package:sembast/sembast.dart';

CHANGELOG.md

@@ -0,0 +1,21 @@
+import 'package:memo/domain/models/deck.dart';
+import 'package:memo/data/serializers/deck_serializer.dart';
+import 'package:memo/data/gateways/document_database_gateway.dart';
+
+abstract class DeckRepository {
+  Future<List<Deck>> getAllDecks();
+}
+
+class DeckRepositoryImpl implements DeckRepository {
+  DeckRepositoryImpl(this._db);
+
+  final DocumentDatabaseGateway _db;
+  final _deckSerializer = DeckSerializer();
+  final _deckStore = 'decks';
+
+  @override
+  Future<List<Deck>> getAllDecks() async {
+    final rawDecks = await _db.getAll(store: _deckStore);
+    return rawDecks.map(_deckSerializer.from).toList();
+  }
+}