feat(hydrated_bloc)!: support for WASM (#4313)

Author: felangel

packages/hydrated_bloc/README.md

@@ -65,8 +65,8 @@ Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
   HydratedBloc.storage = await HydratedStorage.build(
     storageDirectory: kIsWeb
-        ? HydratedStorage.webStorageDirectory
-        : await getApplicationDocumentsDirectory(),
+        ? HydratedStorageDirectory.web
+        : HydratedStorageDirectory((await getTemporaryDirectory()).path),
   );
   runApp(App());
 }

packages/hydrated_bloc/example/lib/main.dart

@@ -9,8 +9,8 @@ void main() async {
   WidgetsFlutterBinding.ensureInitialized();
   HydratedBloc.storage = await HydratedStorage.build(
     storageDirectory: kIsWeb
-        ? HydratedStorage.webStorageDirectory
-        : await getTemporaryDirectory(),
+        ? HydratedStorageDirectory.web
+        : HydratedStorageDirectory((await getTemporaryDirectory()).path),
   );
   runApp(const App());
 }

packages/hydrated_bloc/lib/src/_migration/_migration_io.dart

@@ -0,0 +1,23 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:hive_ce/hive.dart';
+
+/// The storage migration implementation when using dart:io.
+Future<dynamic> migrate(String directory, Box<dynamic> box) async {
+  final file = File('$directory/.hydrated_bloc.json');
+  if (file.existsSync()) {
+    try {
+      final dynamic storageJson = json.decode(await file.readAsString());
+      final cache = (storageJson as Map).cast<String, String>();
+      for (final key in cache.keys) {
+        try {
+          final string = cache[key];
+          final dynamic object = json.decode(string ?? '');
+          await box.put(key, object);
+        } catch (_) {}
+      }
+    } catch (_) {}
+    await file.delete();
+  }
+}

packages/hydrated_bloc/lib/src/_migration/_migration_stub.dart

@@ -0,0 +1,4 @@
+import 'package:hive_ce/hive.dart';
+
+/// The storage migration implementation stub.
+Future<dynamic> migrate(String directory, Box<dynamic> box) async {}

packages/hydrated_bloc/lib/src/hydrated_storage.dart

@@ -1,10 +1,10 @@
 import 'dart:async';
-import 'dart:convert';
-import 'dart:io';
 
 import 'package:hive_ce/hive.dart';
 // ignore: implementation_imports
 import 'package:hive_ce/src/hive_impl.dart';
+import 'package:hydrated_bloc/src/_migration/_migration_stub.dart'
+    if (dart.library.io) 'package:hydrated_bloc/src/_migration/_migration_io.dart';
 import 'package:hydrated_bloc/src/hydrated_cipher.dart';
 import 'package:meta/meta.dart';
 import 'package:synchronized/synchronized.dart';
@@ -28,29 +28,40 @@ abstract class Storage {
   Future<void> close();
 }
 
-/// {@template hydrated_storage}
-/// Implementation of [Storage] which uses [package:hive](https://pub.dev/packages/hive)
-/// to persist and retrieve state changes from the local device.
+/// {@template hydrated_storage_directory}
+/// A platform-agnostic storage directory representation.
 /// {@endtemplate}
-class HydratedStorage implements Storage {
-  /// {@macro hydrated_storage}
-  @visibleForTesting
-  HydratedStorage(this._box);
+class HydratedStorageDirectory {
+  /// {@macro hydrated_storage_directory}
+  const HydratedStorageDirectory(this.path);
+
+  /// The path to the storage directory.
+  final String path;
 
   /// Sentinel directory used to determine that web storage should be used
   /// when initializing [HydratedStorage].
   ///
   /// ```dart
   /// await HydratedStorage.build(
-  ///   storageDirectory: HydratedStorage.webStorageDirectory,
+  ///   storageDirectory: HydratedStorageDirectory.web,
   /// );
   /// ```
-  static final webStorageDirectory = Directory('');
+  static const web = HydratedStorageDirectory('');
+}
+
+/// {@template hydrated_storage}
+/// Implementation of [Storage] which uses [package:hive_ce](https://pub.dev/packages/hive_ce)
+/// to persist and retrieve state changes from the local device.
+/// {@endtemplate}
+class HydratedStorage implements Storage {
+  /// {@macro hydrated_storage}
+  @visibleForTesting
+  HydratedStorage(this._box);
 
   /// Returns an instance of [HydratedStorage].
   /// [storageDirectory] is required.
   ///
-  /// For web, use [webStorageDirectory] as the `storageDirectory`
+  /// For web, use [HydratedStorageDirectory.web] as the `storageDirectory`
   ///
   /// ```dart
   /// import 'package:flutter/foundation.dart';
@@ -63,8 +74,8 @@ class HydratedStorage implements Storage {
   ///   WidgetsFlutterBinding.ensureInitialized();
   ///   HydratedBloc.storage = await HydratedStorage.build(
   ///     storageDirectory: kIsWeb
-  ///         ? HydratedStorage.webStorageDirectory
-  ///         : await getTemporaryDirectory(),
+  ///         ? HydratedStorageDirectory.web
+  ///         : HydratedStorageDirectory((await getTemporaryDirectory()).path),
   ///   );
   ///   runApp(App());
   /// }
@@ -81,7 +92,7 @@ class HydratedStorage implements Storage {
   /// return HydratedAesCipher(byteskey);
   /// ```
   static Future<HydratedStorage> build({
-    required Directory storageDirectory,
+    required HydratedStorageDirectory storageDirectory,
     HydratedCipher? encryptionCipher,
   }) {
     return _lock.synchronized(() async {
@@ -91,7 +102,7 @@ class HydratedStorage implements Storage {
       hive = HiveImpl();
       Box<dynamic> box;
 
-      if (storageDirectory == webStorageDirectory) {
+      if (storageDirectory == HydratedStorageDirectory.web) {
         box = await hive.openBox<dynamic>(
           'hydrated_box',
           encryptionCipher: encryptionCipher,
@@ -102,31 +113,13 @@ class HydratedStorage implements Storage {
           'hydrated_box',
           encryptionCipher: encryptionCipher,
         );
-        await _migrate(storageDirectory, box);
+        await migrate(storageDirectory.path, box);
       }
 
       return _instance = HydratedStorage(box);
     });
   }
 
-  static Future<dynamic> _migrate(Directory directory, Box<dynamic> box) async {
-    final file = File('${directory.path}/.hydrated_bloc.json');
-    if (file.existsSync()) {
-      try {
-        final dynamic storageJson = json.decode(await file.readAsString());
-        final cache = (storageJson as Map).cast<String, String>();
-        for (final key in cache.keys) {
-          try {
-            final string = cache[key];
-            final dynamic object = json.decode(string ?? '');
-            await box.put(key, object);
-          } catch (_) {}
-        }
-      } catch (_) {}
-      await file.delete();
-    }
-  }
-
   /// Internal instance of [HiveImpl].
   /// It should only be used for testing.
   @visibleForTesting

packages/hydrated_bloc/test/e2e_test.dart

@@ -15,7 +15,7 @@ void main() {
 
     setUp(() async {
       storage = await HydratedStorage.build(
-        storageDirectory: Directory(
+        storageDirectory: HydratedStorageDirectory(
           path.join(Directory.current.path, '.cache'),
         ),
       );

packages/hydrated_bloc/test/hydrated_storage_test.dart

@@ -15,7 +15,7 @@ class MockBox extends Mock implements Box<dynamic> {}
 void main() {
   group('HydratedStorage', () {
     final cwd = Directory.current.absolute.path;
-    final storageDirectory = Directory(cwd);
+    final storageDirectory = HydratedStorageDirectory(cwd);
 
     late Storage storage;
 
@@ -78,7 +78,7 @@ void main() {
         await runZonedGuarded(
           () {
             HydratedStorage.build(
-              storageDirectory: HydratedStorage.webStorageDirectory,
+              storageDirectory: HydratedStorageDirectory.web,
             ).whenComplete(completer.complete);
             return completer.future;
           },
@@ -179,7 +179,7 @@ void main() {
       test('writes key/value pairs correctly', () async {
         const token = 'token';
         storage = await HydratedStorage.build(
-          storageDirectory: Directory(cwd),
+          storageDirectory: HydratedStorageDirectory(cwd),
         );
         await Stream.fromIterable(
           Iterable.generate(120, (i) => i),
@@ -193,7 +193,7 @@ void main() {
           storage.write(token, record);
 
           storage = await HydratedStorage.build(
-            storageDirectory: Directory(cwd),
+            storageDirectory: HydratedStorageDirectory(cwd),
           );
 
           final written = storage.read(token) as List<List<String>>;
@@ -217,8 +217,9 @@ void main() {
 
       test('Hive and Hydrated default directories', () async {
         Hive.init(docs);
+        final tempDir = Directory(temp)..createSync();
         storage = await HydratedStorage.build(
-          storageDirectory: Directory(temp)..createSync(),
+          storageDirectory: HydratedStorageDirectory(tempDir.path),
         );
 
         var box = await Hive.openBox<String>('hive');