feat: authentication repository

.vscode/launch.json

@@ -16,13 +16,6 @@
         "lib/main_development.dart"
       ]
     },
-    {
-      "name": "Launch staging",
-      "request": "launch",
-      "type": "dart",
-      "program": "lib/main_staging.dart",
-      "args": ["--flavor", "staging", "--target", "lib/main_staging.dart"]
-    },
     {
       "name": "Launch production",
       "request": "launch",

lib/app/view/app.dart

@@ -1,28 +1,35 @@
 import 'package:api_client/api_client.dart';
+import 'package:authentication_repository/authentication_repository.dart';
 import 'package:dash_ai_search/counter/counter.dart';
 import 'package:dash_ai_search/l10n/l10n.dart';
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
 
 class App extends StatelessWidget {
   const App({
     required this.apiClient,
+    required this.user,
     super.key,
   });
 
   final ApiClient apiClient;
+  final User user;
 
   @override
   Widget build(BuildContext context) {
-    return MaterialApp(
-      theme: ThemeData(
-        appBarTheme: AppBarTheme(
-          backgroundColor: Theme.of(context).colorScheme.inversePrimary,
+    return Provider.value(
+      value: user,
+      child: MaterialApp(
+        theme: ThemeData(
+          appBarTheme: AppBarTheme(
+            backgroundColor: Theme.of(context).colorScheme.inversePrimary,
+          ),
+          useMaterial3: true,
         ),
-        useMaterial3: true,
+        localizationsDelegates: AppLocalizations.localizationsDelegates,
+        supportedLocales: AppLocalizations.supportedLocales,
+        home: const CounterPage(),
       ),
-      localizationsDelegates: AppLocalizations.localizationsDelegates,
-      supportedLocales: AppLocalizations.supportedLocales,
-      home: const CounterPage(),
     );
   }
 }

lib/bootstrap.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:developer';
 
 import 'package:bloc/bloc.dart';
+import 'package:firebase_auth/firebase_auth.dart';
 import 'package:flutter/widgets.dart';
 
 class AppBlocObserver extends BlocObserver {
@@ -20,14 +21,20 @@ class AppBlocObserver extends BlocObserver {
   }
 }
 
-Future<void> bootstrap(FutureOr<Widget> Function() builder) async {
+typedef BootstrapBuilder = FutureOr<Widget> Function(FirebaseAuth);
+
+Future<void> bootstrap(BootstrapBuilder builder) async {
+  WidgetsFlutterBinding.ensureInitialized();
+
   FlutterError.onError = (details) {
     log(details.exceptionAsString(), stackTrace: details.stack);
   };
 
   Bloc.observer = const AppBlocObserver();
 
-  // Add cross-flavor configuration here
-
-  runApp(await builder());
+  runApp(
+    await builder(
+      FirebaseAuth.instance,
+    ),
+  );
 }

lib/main_development.dart

@@ -1,19 +1,33 @@
+import 'dart:async';
+
 import 'package:api_client/api_client.dart';
+import 'package:authentication_repository/authentication_repository.dart';
 import 'package:dash_ai_search/app/app.dart';
 import 'package:dash_ai_search/bootstrap.dart';
+import 'package:firebase_core/firebase_core.dart';
+
+void main() async {
+  await Firebase.initializeApp();
+
+  unawaited(
+    bootstrap((firebaseAuth) async {
+      final authenticationRepository = AuthenticationRepository(
+        firebaseAuth: firebaseAuth,
+      );
 
-void main() {
-  bootstrap(
-    () {
       final apiClient = ApiClient(
         baseUrl: 'http://localhost:8080',
-        idTokenStream: const Stream.empty(),
-        refreshIdToken: () async => Future.value(),
+        idTokenStream: authenticationRepository.idToken,
+        refreshIdToken: authenticationRepository.refreshIdToken,
       );
 
+      await authenticationRepository.signInAnonymously();
+      await authenticationRepository.idToken.first;
+
       return App(
         apiClient: apiClient,
+        user: await authenticationRepository.user.first,
       );
-    },
+    }),
   );
 }

lib/main_production.dart

@@ -1,19 +1,33 @@
+import 'dart:async';
+
 import 'package:api_client/api_client.dart';
+import 'package:authentication_repository/authentication_repository.dart';
 import 'package:dash_ai_search/app/app.dart';
 import 'package:dash_ai_search/bootstrap.dart';
+import 'package:firebase_core/firebase_core.dart';
+
+void main() async {
+  await Firebase.initializeApp();
+
+  unawaited(
+    bootstrap((firebaseAuth) async {
+      final authenticationRepository = AuthenticationRepository(
+        firebaseAuth: firebaseAuth,
+      );
 
-void main() {
-  bootstrap(
-    () {
       final apiClient = ApiClient(
         baseUrl: 'http://production',
-        idTokenStream: const Stream.empty(),
-        refreshIdToken: () async => Future.value(),
+        idTokenStream: authenticationRepository.idToken,
+        refreshIdToken: authenticationRepository.refreshIdToken,
       );
 
+      await authenticationRepository.signInAnonymously();
+      await authenticationRepository.idToken.first;
+
       return App(
         apiClient: apiClient,
+        user: await authenticationRepository.user.first,
       );
-    },
+    }),
   );
 }

packages/authentication_repository/.gitignore

@@ -0,0 +1,44 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# VSCode related
+.vscode/*
+
+# Flutter/Dart/Pub related
+**/doc/api/
+**/ios/Flutter/.last_build_id
+.dart_tool/
+.flutter-plugins
+.flutter-plugins-dependencies
+.packages
+.pub-cache/
+.pub/
+/build/
+pubspec.lock
+
+# Web related
+lib/generated_plugin_registrant.dart
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Test related
+coverage

packages/authentication_repository/README.md

@@ -0,0 +1,12 @@
+# Authentication Repository
+
+[![style: very good analysis][very_good_analysis_badge]][very_good_analysis_link]
+[![Powered by Mason](https://img.shields.io/endpoint?url=https%3A%2F%2Ftinyurl.com%2Fmason-badge)](https://github.com/felangel/mason)
+[![License: MIT][license_badge]][license_link]
+
+Repository to manage authentication.
+
+[license_badge]: https://img.shields.io/badge/license-MIT-blue.svg
+[license_link]: https://opensource.org/licenses/MIT
+[very_good_analysis_badge]: https://img.shields.io/badge/style-very_good_analysis-B22C89.svg
+[very_good_analysis_link]: https://pub.dev/packages/very_good_analysis

packages/authentication_repository/analysis_options.yaml

@@ -0,0 +1 @@
+include: package:very_good_analysis/analysis_options.5.1.0.yaml

packages/authentication_repository/lib/authentication_repository.dart

@@ -0,0 +1,5 @@
+/// Repository to manage authentication.s
+library authentication_repository;
+
+export 'src/authentication_repository.dart';
+export 'src/models/models.dart';

packages/authentication_repository/lib/src/authentication_repository.dart

@@ -0,0 +1,87 @@
+import 'dart:async';
+
+import 'package:authentication_repository/authentication_repository.dart';
+import 'package:firebase_auth/firebase_auth.dart' as fb;
+
+/// {@template authentication_exception}
+/// Exception thrown when an authentication process fails.
+/// {@endtemplate}
+class AuthenticationException implements Exception {
+  /// {@macro authentication_exception}
+  const AuthenticationException(this.error, this.stackTrace);
+
+  /// The error that was caught.
+  final Object error;
+
+  /// The stack trace associated with the error.
+  final StackTrace stackTrace;
+}
+
+/// {@template authentication_repository}
+/// Repository to manage authentication.
+/// {@endtemplate}
+class AuthenticationRepository {
+  /// {@macro authentication_repository}
+  AuthenticationRepository({
+    fb.FirebaseAuth? firebaseAuth,
+  })  : _firebaseAuth = firebaseAuth ?? fb.FirebaseAuth.instance,
+        _userController = StreamController<User>.broadcast();
+
+  final fb.FirebaseAuth _firebaseAuth;
+  final StreamController<User> _userController;
+  StreamSubscription<fb.User?>? _firebaseUserSubscription;
+
+  /// Stream of [User] which will emit the current user when
+  /// the authentication state changes.
+  ///
+  /// Emits [User.unauthenticated] if the user is not authenticated.
+  Stream<User> get user {
+    _firebaseUserSubscription ??=
+        _firebaseAuth.authStateChanges().listen((firebaseUser) {
+      _userController.add(
+        firebaseUser?.toUser ?? User.unauthenticated,
+      );
+    });
+
+    return _userController.stream;
+  }
+
+  /// Stream of id tokens that can be used to authenticate with Firebase.
+  Stream<String?> get idToken {
+    return _firebaseAuth
+        .idTokenChanges()
+        .asyncMap((user) => user?.getIdToken());
+  }
+
+  /// Refreshes the id token.
+  Future<String?> refreshIdToken() async {
+    final user = _firebaseAuth.currentUser;
+    return user?.getIdToken(true);
+  }
+
+  /// Sign in the user anonymously.
+  ///
+  /// If the sign in fails, an [AuthenticationException] is thrown.
+  Future<void> signInAnonymously() async {
+    try {
+      final userCredential = await _firebaseAuth.signInAnonymously();
+      _userController.add(userCredential.toUser);
+    } on Exception catch (error, stackTrace) {
+      throw AuthenticationException(error, stackTrace);
+    }
+  }
+
+  /// Disposes any internal resources.
+  void dispose() {
+    _firebaseUserSubscription?.cancel();
+    _userController.close();
+  }
+}
+
+extension on fb.User {
+  User get toUser => User(id: uid);
+}
+
+extension on fb.UserCredential {
+  User get toUser => user?.toUser ?? User.unauthenticated;
+}

packages/authentication_repository/lib/src/models/models.dart

@@ -0,0 +1 @@
+export 'user.dart';

packages/authentication_repository/lib/src/models/user.dart

@@ -0,0 +1,20 @@
+import 'package:equatable/equatable.dart';
+
+/// {@template user}
+/// User model
+/// {@endtemplate}
+class User extends Equatable {
+  /// {@macro user}
+  const User({
+    required this.id,
+  });
+
+  /// The current user's id.
+  final String id;
+
+  /// Represents an unauthenticated user.
+  static const unauthenticated = User(id: '');
+
+  @override
+  List<Object?> get props => [id];
+}