Flutter GoRouter with Firebase Auth - flutter

Question

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Chris wants to draw more attention to this question.
I am using the go_router and Firebase Auth for my web application but can not properly set it up. I tried this:
class AuthService {
static final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
static User? get currentUser => FirebaseAuth.instance.currentUser;
static bool isLoggedIn() {
return _firebaseAuth.currentUser != null;
}
...
With my router:
redirect: (context, state) {
final String destination = state.location;
final bool isOnStartView = destination == '/start';
final bool isOnEmailFlow = state.subloc.contains('/email');
if (!isOnStartView && !isOnEmailFlow && !AuthService.isLoggedIn()) {
return '/start';
}
return null;
},
However this is not working properly as isLoggedIn is always return false even if there a is a user logged in. I searched for this topic and found that I probably use some sort of Stream or Notifier with onAuthStateChange but I didn't find anything on how to implement a proper FirebaseAuthentication Flow in combination with GoRouter.
How would I do that?
Let me know if you need any more info.

Answer 1

You can use riverpod or provider to listen changes
here is code sample
import 'dart:developer';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';
import 'package:testproject/Home%20Screen/home_screen.dart';
import 'package:testproject/Model/user_model.dart';
import 'package:testproject/Providers/UserProvider/user_data_provider.dart';
import 'package:testproject/Screens/login_screen.dart';
import 'package:testproject/Screens/sign_up.dart';
import 'package:testproject/Service/auth_service.dart';
import '../Providers/Satates/user_states.dart';
import '../Providers/UserProvider/user_state_provider.dart';
class MyRoutes extends ChangeNotifier {
final Ref ref;
MyRoutes(this.ref) {
ref.listen<LoginState>(
userStateprovider, (previous, next) => notifyListeners());
}
List<GoRoute> get _routes => [
GoRoute(
name: "Login",
path: "/login",
builder: (context, state) => SigninPage(),
),
GoRoute(
name: "Home",
path: "/home",
builder: (context, state) => const HomeScreen(),
),
GoRoute(
name: "Signup",
path: "/signup",
builder: (context, state) => const SignUpScreen(),
),
];
String? _redirectLogic(GoRouterState state) {
final loginState = ref.read(userStateprovider);
final user = ref.read(userProvider.state);
if (loginState is LoginStateInitial && auth.currentUser != null) {
log("message");
Future.delayed(const Duration(seconds: 0), () {
user.state = UserModel(
email: auth.currentUser!.email!, userid: auth.currentUser!.uid);
ref.read(userStateprovider.notifier).newstate = LoginStateSuccess(
UserModel(
email: auth.currentUser!.email!,
userid: auth.currentUser!.uid));
});
}
log(state.location);
log(auth.currentUser.toString());
final areWeLoggingIn = state.location == '/home';
log(areWeLoggingIn.toString());
if (areWeLoggingIn) {
return loginState is LoginStateSuccess ? null : "/login";
}
return null;
}
}
final routeProvider = Provider<GoRouter>((ref) {
final routeRef = MyRoutes(ref);
return GoRouter(
urlPathStrategy: UrlPathStrategy.path,
initialLocation: "/login",
refreshListenable: routeRef,
redirect: routeRef._redirectLogic,
routes: routeRef._routes);
});

Answer 2

You can do this
class AuthService {
static final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
static User? get currentUser => FirebaseAuth.instance.currentUser;
static bool? _isLoggedIn = null;
static bool isLoggedIn() {
if(_isLoggedIn == null) {
FirebaseAuth.instance
.authStateChanges()
.listen((User? user) {
_isLoggedIn = user?.uid != null;
});
_isLoggedIn = _firebaseAuth.currentUser?.uid != null;
return _isLoggedIn ?? false;
}
else {
return _isLoggedIn ?? false;
}
...