fix(firebase_auth): pass Persistence value to `FirebaseAuth.instanc…

…eFor(app: app, persistence: persistence)` for setting persistence on Web platform (#9138)

Co-authored-by: Mike Diarmid <mike.diarmid@gmail.com>

docs/auth/start.md

@@ -211,13 +211,14 @@ On web platforms, the user's authentication state is stored in
 [local storage](https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage).
 If required, you can change this default behavior to only persist
 authentication state for the current session, or not at all. To configure these
-settings, call the `setPersistence()` method. (On native platforms, an
-[`UnimplementedError`](https://api.flutter.dev/flutter/dart-core/UnimplementedError-class.html)
-will be thrown.)
+settings, call the following method `FirebaseAuth.instanceFor(app: Firebase.app(), persistence: Persistence.LOCAL);`.
+You can still update the persistence for each Auth instance using `setPersistence(Persistence.NONE)`.
 
 ```dart
-// Disable persistence on web platforms
-await FirebaseAuth.instance.setPersistence(Persistence.NONE);
+// Disable persistence on web platforms. Must be called on initialization:
+final auth = FirebaseAuth.instanceFor(app: Firebase.app(), persistence: Persistence.NONE);
+// To change it after initialization, use `setPersistence()`:
+await auth.setPersistence(Persistence.LOCAL);
 ```
 
 ## Next Steps

packages/firebase_auth/firebase_auth/example/lib/main.dart

@@ -14,7 +14,6 @@ bool shouldUseFirebaseEmulator = false;
 // e.g via `melos run firebase:emulator`.
 Future<void> main() async {
   WidgetsFlutterBinding.ensureInitialized();
-
   // We're using the manual installation on non-web platforms since Google sign in plugin doesn't yet support Dart initialization.
   // See related issue: https://github.com/flutter/flutter/issues/96391
   if (!kIsWeb) {

packages/firebase_auth/firebase_auth/lib/src/firebase_auth.dart

@@ -15,6 +15,10 @@ class FirebaseAuth extends FirebasePluginPlatform {
   // instance with the default app before a user specifies an app.
   FirebaseAuthPlatform? _delegatePackingProperty;
 
+  // To set "persistence" on web, it is now required on the v9.0.0 or above Firebase JS SDK to pass the value on calling `initializeAuth()`.
+  /// https://firebase.google.com/docs/reference/js/auth.md#initializeauth
+  Persistence? _persistence;
+
   /// Returns the underlying delegate implementation.
   ///
   /// If called and no [_delegatePackingProperty] exists, it will first be
@@ -23,15 +27,17 @@ class FirebaseAuth extends FirebasePluginPlatform {
     _delegatePackingProperty ??= FirebaseAuthPlatform.instanceFor(
       app: app,
       pluginConstants: pluginConstants,
+      persistence: _persistence,
     );
     return _delegatePackingProperty!;
   }
 
   /// The [FirebaseApp] for this current Auth instance.
   FirebaseApp app;
 
-  FirebaseAuth._({required this.app})
-      : super(app.name, 'plugins.flutter.io/firebase_auth');
+  FirebaseAuth._({required this.app, Persistence? persistence})
+      : _persistence = persistence,
+        super(app.name, 'plugins.flutter.io/firebase_auth');
 
   /// Returns an instance using the default [FirebaseApp].
   static FirebaseAuth get instance {
@@ -41,9 +47,11 @@ class FirebaseAuth extends FirebasePluginPlatform {
   }
 
   /// Returns an instance using a specified [FirebaseApp].
-  factory FirebaseAuth.instanceFor({required FirebaseApp app}) {
+  /// Note that persistence can only be used on Web and is not supported on other platforms.
+  factory FirebaseAuth.instanceFor(
+      {required FirebaseApp app, Persistence? persistence}) {
     return _firebaseAuthInstances.putIfAbsent(app.name, () {
-      return FirebaseAuth._(app: app);
+      return FirebaseAuth._(app: app, persistence: persistence);
     });
   }
 

packages/firebase_auth/firebase_auth/test/firebase_auth_test.dart

@@ -728,7 +728,8 @@ class MockFirebaseAuth extends Mock
   }
 
   @override
-  FirebaseAuthPlatform delegateFor({FirebaseApp? app}) {
+  FirebaseAuthPlatform delegateFor(
+      {FirebaseApp? app, Persistence? persistence}) {
     return super.noSuchMethod(
       Invocation.method(#delegateFor, [], {#app: app}),
       returnValue: TestFirebaseAuthPlatform(),
@@ -1024,7 +1025,8 @@ class FakeFirebaseAuthPlatform extends Fake
   String? tenantId;
 
   @override
-  FirebaseAuthPlatform delegateFor({required FirebaseApp app}) {
+  FirebaseAuthPlatform delegateFor(
+      {required FirebaseApp app, Persistence? persistence}) {
     return this;
   }
 
@@ -1085,7 +1087,8 @@ class TestFirebaseAuthPlatform extends FirebaseAuthPlatform {
   }) {}
 
   @override
-  FirebaseAuthPlatform delegateFor({FirebaseApp? app}) {
+  FirebaseAuthPlatform delegateFor(
+      {FirebaseApp? app, Persistence? persistence}) {
     return this;
   }
 

packages/firebase_auth/firebase_auth/test/user_test.dart

@@ -374,7 +374,8 @@ class MockFirebaseAuth extends Mock
   }
 
   @override
-  FirebaseAuthPlatform delegateFor({FirebaseApp? app}) {
+  FirebaseAuthPlatform delegateFor(
+      {FirebaseApp? app, Persistence? persistence}) {
     return super.noSuchMethod(
       Invocation.method(#delegateFor, const [], {#app: app}),
       returnValue: TestFirebaseAuthPlatform(),
@@ -555,7 +556,9 @@ class TestFirebaseAuthPlatform extends FirebaseAuthPlatform {
   TestFirebaseAuthPlatform() : super();
 
   @override
-  FirebaseAuthPlatform delegateFor({FirebaseApp? app}) => this;
+  FirebaseAuthPlatform delegateFor(
+          {FirebaseApp? app, Persistence? persistence}) =>
+      this;
 
   @override
   FirebaseAuthPlatform setInitialValues({

packages/firebase_auth/firebase_auth_platform_interface/lib/src/method_channel/method_channel_firebase_auth.dart

@@ -187,7 +187,8 @@ class MethodChannelFirebaseAuth extends FirebaseAuthPlatform {
   ///
   /// Instances are cached and reused for incoming event handlers.
   @override
-  FirebaseAuthPlatform delegateFor({required FirebaseApp app}) {
+  FirebaseAuthPlatform delegateFor(
+      {required FirebaseApp app, Persistence? persistence}) {
     return methodChannelFirebaseAuthInstances.putIfAbsent(app.name, () {
       return MethodChannelFirebaseAuth(app: app);
     });

packages/firebase_auth/firebase_auth_platform_interface/lib/src/platform_interface/platform_interface_firebase_auth.dart

@@ -48,15 +48,18 @@ abstract class FirebaseAuthPlatform extends PlatformInterface {
   static final Object _token = Object();
 
   /// Create an instance using [app] using the existing implementation
-  factory FirebaseAuthPlatform.instanceFor({
-    required FirebaseApp app,
-    required Map<dynamic, dynamic> pluginConstants,
-  }) {
-    return FirebaseAuthPlatform.instance.delegateFor(app: app).setInitialValues(
-        languageCode: pluginConstants['APP_LANGUAGE_CODE'],
-        currentUser: pluginConstants['APP_CURRENT_USER'] == null
-            ? null
-            : Map<String, dynamic>.from(pluginConstants['APP_CURRENT_USER']));
+  factory FirebaseAuthPlatform.instanceFor(
+      {required FirebaseApp app,
+      required Map<dynamic, dynamic> pluginConstants,
+      Persistence? persistence}) {
+    return FirebaseAuthPlatform.instance
+        .delegateFor(app: app, persistence: persistence)
+        .setInitialValues(
+            languageCode: pluginConstants['APP_LANGUAGE_CODE'],
+            currentUser: pluginConstants['APP_CURRENT_USER'] == null
+                ? null
+                : Map<String, dynamic>.from(
+                    pluginConstants['APP_CURRENT_USER']));
   }
 
   /// The current default [FirebaseAuthPlatform] instance.
@@ -79,7 +82,8 @@ abstract class FirebaseAuthPlatform extends PlatformInterface {
   /// Enables delegates to create new instances of themselves if a none default
   /// [FirebaseApp] instance is required by the user.
   @protected
-  FirebaseAuthPlatform delegateFor({required FirebaseApp app}) {
+  FirebaseAuthPlatform delegateFor(
+      {required FirebaseApp app, Persistence? persistence}) {
     throw UnimplementedError('delegateFor() is not implemented');
   }
 

packages/firebase_auth/firebase_auth_web/lib/firebase_auth_web.dart

@@ -32,8 +32,14 @@ class FirebaseAuthWeb extends FirebaseAuthPlatform {
 
   Completer<void> _initialized = Completer();
 
+  // To set "persistence" on web, it is now required on the v9.0.0 or above Firebase JS SDK to pass the value on calling `initializeAuth()`.
+  // https://firebase.google.com/docs/reference/js/auth.md#initializeauth
+  Persistence? _persistence;
+
   /// The entry point for the [FirebaseAuthWeb] class.
-  FirebaseAuthWeb({required FirebaseApp app}) : super(appInstance: app) {
+  FirebaseAuthWeb({required FirebaseApp app, Persistence? persistence})
+      : super(appInstance: app) {
+    _persistence = persistence;
     // Create a app instance broadcast stream for both delegate listener events
     _userChangesListeners[app.name] =
         StreamController<UserPlatform?>.broadcast();
@@ -100,13 +106,16 @@ class FirebaseAuthWeb extends FirebaseAuthPlatform {
   auth_interop.Auth? _webAuth;
 
   auth_interop.Auth get delegate {
-    return _webAuth ??=
-        auth_interop.getAuthInstance(core_interop.app(app.name));
+    _webAuth ??= auth_interop.getAuthInstance(core_interop.app(app.name),
+        persistence: _persistence);
+
+    return _webAuth!;
   }
 
   @override
-  FirebaseAuthPlatform delegateFor({required FirebaseApp app}) {
-    return FirebaseAuthWeb(app: app);
+  FirebaseAuthPlatform delegateFor(
+      {required FirebaseApp app, Persistence? persistence}) {
+    return FirebaseAuthWeb(app: app, persistence: persistence);
   }
 
   @override

packages/firebase_auth/firebase_auth_web/lib/src/interop/auth.dart

@@ -20,11 +20,34 @@ import 'utils/utils.dart';
 export 'auth_interop.dart';
 
 /// Given an AppJSImp, return the Auth instance.
-Auth getAuthInstance(App app) {
+Auth getAuthInstance(App app, {Persistence? persistence}) {
+  if (persistence != null) {
+    auth_interop.Persistence setPersistence;
+    switch (persistence) {
+      case Persistence.LOCAL:
+        setPersistence = auth_interop.browserLocalPersistence;
+        break;
+      case Persistence.SESSION:
+        setPersistence = auth_interop.browserSessionPersistence;
+        break;
+      case Persistence.NONE:
+        setPersistence = auth_interop.inMemoryPersistence;
+        break;
+    }
+    return Auth.getInstance(auth_interop.initializeAuth(
+        app.jsObject,
+        jsify({
+          'errorMap': auth_interop.debugErrorMap,
+          'persistence': setPersistence,
+          'popupRedirectResolver': auth_interop.browserPopupRedirectResolver
+        })));
+  }
+  // `browserLocalPersistence` is the default persistence setting.
   return Auth.getInstance(auth_interop.initializeAuth(
       app.jsObject,
       jsify({
         'errorMap': auth_interop.debugErrorMap,
+        'persistence': auth_interop.browserLocalPersistence,
         'popupRedirectResolver': auth_interop.browserPopupRedirectResolver
       })));
 }
@@ -497,30 +520,6 @@ class Auth extends JsObjectWrapper<auth_interop.AuthJsImpl> {
       handleThenable(auth_interop.sendSignInLinkToEmail(
           jsObject, email, actionCodeSettings));
 
-  /// Sends a password reset e-mail to the given [email].
-  /// To confirm password reset, use the [Auth.confirmPasswordReset].
-  ///
-  /// The optional parameter [actionCodeSettings] is the action code settings.
-  /// If specified, the state/continue URL will be set as the 'continueUrl'
-  /// parameter in the password reset link.
-  /// The default password reset landing page will use this to display
-  /// a link to go back to the app if it is installed.
-  ///
-  /// If the [actionCodeSettings] is not specified, no URL is appended to the
-  /// action URL. The state URL provided must belong to a domain that is
-  /// whitelisted by the developer in the console. Otherwise an error will be
-  /// thrown.
-  ///
-  /// Mobile app redirects will only be applicable if the developer configures
-  /// and accepts the Firebase Dynamic Links terms of condition.
-  ///
-  /// The Android package name and iOS bundle ID will be respected only if
-  /// they are configured in the same Firebase Auth project used.
-  Future sendPasswordResetEmail(String email,
-          [auth_interop.ActionCodeSettings? actionCodeSettings]) =>
-      handleThenable(auth_interop.sendPasswordResetEmail(
-          jsObject, email, actionCodeSettings));
-
   /// Changes the current type of persistence on the current Auth instance for
   /// the currently saved Auth session and applies this type of persistence
   /// for future sign-in requests, including sign-in with redirect requests.
@@ -554,6 +553,30 @@ class Auth extends JsObjectWrapper<auth_interop.AuthJsImpl> {
     return handleThenable(auth_interop.setPersistence(jsObject, instance));
   }
 
+  /// Sends a password reset e-mail to the given [email].
+  /// To confirm password reset, use the [Auth.confirmPasswordReset].
+  ///
+  /// The optional parameter [actionCodeSettings] is the action code settings.
+  /// If specified, the state/continue URL will be set as the 'continueUrl'
+  /// parameter in the password reset link.
+  /// The default password reset landing page will use this to display
+  /// a link to go back to the app if it is installed.
+  ///
+  /// If the [actionCodeSettings] is not specified, no URL is appended to the
+  /// action URL. The state URL provided must belong to a domain that is
+  /// whitelisted by the developer in the console. Otherwise an error will be
+  /// thrown.
+  ///
+  /// Mobile app redirects will only be applicable if the developer configures
+  /// and accepts the Firebase Dynamic Links terms of condition.
+  ///
+  /// The Android package name and iOS bundle ID will be respected only if
+  /// they are configured in the same Firebase Auth project used.
+  Future sendPasswordResetEmail(String email,
+          [auth_interop.ActionCodeSettings? actionCodeSettings]) =>
+      handleThenable(auth_interop.sendPasswordResetEmail(
+          jsObject, email, actionCodeSettings));
+
   /// Asynchronously signs in with the given credentials, and returns any
   /// available additional user information, such as user name.
   Future<UserCredential> signInWithCredential(

tests/test_driver/firebase_auth/firebase_auth_instance_e2e.dart

@@ -481,7 +481,7 @@ void setupTests() {
     group('setPersistence()', () {
       test(
         'throw an unimplemented error',
-        () async {
+            () async {
           try {
             await FirebaseAuth.instance.setPersistence(Persistence.LOCAL);
             fail('Should have thrown');
@@ -494,7 +494,7 @@ void setupTests() {
 
       test(
         'should set persistence',
-        () async {
+            () async {
           try {
             await FirebaseAuth.instance.setPersistence(Persistence.LOCAL);
           } catch (e) {