I have problems with the Flutter code for the Firebase email/password sign-in.
When email address and password are correct, nothing happens.
When email address or password are not correct the "Error "+errMsg.toString() is generated.
In console I read:
W/System (21892): Ignoring header X-Firebase-Locale because its value
was null. D/FirebaseAuth(21892): Notifying id token listeners about
user ( R6GCSXPvbUgbu4uQXdLYtXD1Lyo1 ).
Here is the code:
final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
void loginAndAuthenticateUser(BuildContext context) async{
final User firebaseUser = (await _firebaseAuth.signInWithEmailAndPassword(
email: emailTextEditingController.text,
password: passwordTextEditingController.text)
.catchError((errMsg) {
displayToastMessage("Error " + errMsg.toString(), context);
})).user;
if (firebaseUser != null) {
usersRef.child(firebaseUser.uid).once().then((DataSnapshot snap){
if (snap.value == null){
Navigator.pushNamedAndRemoveUntil(context, MainScreen.idScreen, (route) => false);
displayToastMessage("You are logged in.", context);
}
else{
_firebaseAuth.signOut();
displayToastMessage("User not found.", context);
}
});
}
else{
displayToastMessage("Error occurred.", context);
}
}
displayToastMessage(String message, BuildContext context) {
Fluttertoast.showToast(msg: message);
}
In this case the best thing that I know to do is do a "try" "except" statement, I have definitely come across this problem before and wish it was easier to manage.
Related
I'm currently testing my app, when I try to register a new account with an email already it in use, I get the following error:
ArgumentError (Invalid argument(s) (onError): The error handler of Future.catchError must return a value of the future's type)
When I click sign in the app still informs the user that this email is already in use but the error crashes the app. If I try to test any of the other errors, my app does not crash.
I'm not quite sure how to begin to resolve this due to not really being sure why is error is occurring.
*.dart
void signUp(String email, String password) async {
if (GlobalKey<FormState>().currentState!.validate()) {
try {
await FirebaseAuth.instance //<--- Error stops here
.createUserWithEmailAndPassword(email: email, password: password)
.then((value) => {postDetailsToFirestore()})
.catchError((e) {
Fluttertoast.showToast(msg: e!.message);
});
} on FirebaseAuthException catch (error) {
switch (error.code) {
case "invalid-email":
errorMessage = "Your email address appears to be incorrect.";
break;
case "wrong-password":
errorMessage = "Your password is wrong.";
break;
case "user-not-found":
errorMessage = "User with this email doesn't exist.";
break;
case "user-disabled":
errorMessage = "User with this email has been disabled.";
break;
case "too-many-requests":
errorMessage = "Too many requests";
break;
case "operation-not-allowed":
errorMessage = "Signing in with Email and Password is not enabled.";
break;
default:
errorMessage = "An undefined Error happened.";
}
Fluttertoast.showToast(msg: errorMessage!);
print(error.code);
}
}
}
postDetailsToFirestore() async {
FirebaseFirestore firebaseFirestore = FirebaseFirestore.instance;
User? user = _auth.currentUser;
UserModel userModel = UserModel();
// writing all the values
userModel.email = user!.email;
userModel.uid = user.uid;
userModel.userName = NameEditingController.text;
userModel.password = passwordEditingController.text;
await firebaseFirestore
.collection("users")
.doc(user.uid)
.set(userModel.toMap());
Fluttertoast.showToast(msg: "Account created successfully ");
Navigator.pushAndRemoveUntil(
(context),
MaterialPageRoute(builder: (context) => HomeScreen()),
(route) => false);
}
async/await is just a syntactic sugar to handle promises. It makes your code more readable, and combining it with try/catch you can have a more clear way of handling exceptions.
I also recommend to handle the situation if the mobile device does not have Internet access, and a SocketException is thrown. For this kind of exception you need import 'dart:io';
Don't forget to add a simple catch as well, because you can have exceptions other than FirebaseAuthException and SocketException, and these will be not caught if you use only on.(You don't need the catch after on.)
Try it this way:
try {
await FirebaseAuth.instance.createUserWithEmailAndPassword(email: email,
password: password);
await postDetailsToFirestore();
} on FirebaseAuthException (error) {
...
} on SocketException {
...
} catch (e) {
..
}
I am trying to create a signup page which should give an error message if user with particular email id already exist. But it's not working.
signUp() {
if (formkey.currentState!.validate()) {
Map<String, String> userDataMap = {
"name": usernameC.text,
"email": emailC.text
};
setState(() {
isLoading = true;
});
authMethods.signUp(emailC.text, passwordC.text).then((value) {
databaseMethods.uploadUserData(userDataMap);
Navigator.pushReplacement(
context, MaterialPageRoute(builder: (context) => ChatRoom()));
});
}
}
It calls the signUp() function from auth.dart given below
UserData? _userFromFirebase(User? user) {
return user != null ? UserData(userid: user.uid) : null;
}
Future signUp(String email, String pass) async {
try {
UserCredential result = await _auth.createUserWithEmailAndPassword(
email: email, password: pass);
User? user = result.user;
return _userFromFirebase(user);
} catch (e) {
print(e}
}
Every time I signup with same email it doesn't give any error.
If you sign up with the same email you should get this message:
[firebase_auth/email-already-in-use] The email address is already in use by another account.
I use print(e.hashCode) and then use this hash code to show an error message.
Ok I tried this method and it worked out. Just added null check for the "value" attribute in.
authMethods.signUp(emailC.text, passwordC.text).then((value)
It was returning null without any other message. That's why I was unable to see the error.
I am trying to implement the example given at How do I access custom claims? to my existing code.
I have a Stream which listens to auth changes and updates my own user object with the responded Firebase user. When I store my user object, I would like to get the custom claims of that user as well.
The problem is in _userFromFirebaseUser.
It says "The await expression can only be used in an async function.
Try marking the function body with either 'async' or 'async*'."
But when I do so, the error is hops to my stream where it then says "The argument type 'Future Function(User)' can't be assigned to the parameter type 'User Function(User)'." for "_userFromFirebaseUser" in
// auth change user stream
Stream<local.User> get user {
return _auth.authStateChanges().map(_userFromFirebaseUser);
}
Here is my complete authentication class:
import 'package:<my-pckg>/models/user.dart' as local;
import 'package:firebase_auth/firebase_auth.dart' as auth;
import 'package:<my-pckg>/services/database.dart';
//import 'package:shared_preferences/shared_preferences.dart';
class AuthService {
final auth.FirebaseAuth _auth = auth.FirebaseAuth.instance;
// create user obj based on firebase user
local.User _userFromFirebaseUser(auth.User user) {
final isAdmin = (await _currentUserClaims)['admin'] == true;
return user != null
? local.User(
uid: user.uid,
email: user.email,
displayName: user.displayName,
isAdmin: isAdmin)
: null;
}
// auth change user stream
Stream<local.User> get user {
return _auth.authStateChanges().map(_userFromFirebaseUser);
}
// sign in anon
Future signInAnon() async {
try {
auth.UserCredential result = await _auth.signInAnonymously();
auth.User user = result.user;
return _userFromFirebaseUser(user);
} catch (e) {
print(e.toString());
return null;
}
}
// sign in with email and password
Future signInWithEmailAndPassword(String email, String password) async {
try {
auth.UserCredential result = await _auth.signInWithEmailAndPassword(
email: email, password: password);
auth.User user = result.user;
print('Successfully logged in, User UID: ${user.uid}');
return user;
} catch (error) {
print(error.toString());
return null;
}
}
// register with email and password
Future registerWithEmailAndPassword(String email, String password) async {
try {
auth.UserCredential result = await _auth.createUserWithEmailAndPassword(
email: email, password: password);
auth.User user = result.user;
// create a new document for the user with the uid
await DatabaseService(uid: user.uid).updateUserData(null);
print('Successfully registered, User UID: ${user.uid}');
return _userFromFirebaseUser(user);
} catch (error) {
print(error.toString());
return null;
}
}
// sign out
Future signOut() async {
try {
print('User signed out');
return await _auth.signOut();
} catch (error) {
print(error.toString());
return null;
}
}
Future<Map<dynamic, dynamic>> get _currentUserClaims async {
final user = _auth.currentUser;
// If refresh is set to true, a refresh of the id token is forced.
final idTokenResult = await user.getIdTokenResult(true);
return idTokenResult.claims;
}
}
Am I heading into the wrong direction? Is there anything obvious, that I simply do not consider?
Thanks for your help!
For those, heading into the same problem, I found the solution after further research:
You will have to change the .map to .asyncMap.
Here is the code, which works for me:
import 'package:<my-pckg>/models/user.dart' as local;
import 'package:firebase_auth/firebase_auth.dart' as auth;
import 'package:<my-pckg>/services/database.dart';
//import 'package:shared_preferences/shared_preferences.dart';
class AuthService {
final auth.FirebaseAuth _auth = auth.FirebaseAuth.instance;
// create user obj based on firebase user
Future<local.User> _userFromFirebaseUser(auth.User user) async {
final isAdmin = (await _userClaims)['admin'] == true;
return user != null
? local.User(
uid: user.uid,
email: user.email,
displayName: user.displayName,
isAdmin: isAdmin)
: null;
}
// auth change user stream
Stream<local.User> get user {
return _auth.authStateChanges().asyncMap(_userFromFirebaseUser);
}
// sign in anon
Future signInAnon() async {
try {
auth.UserCredential result = await _auth.signInAnonymously();
auth.User user = result.user;
return _userFromFirebaseUser(user);
} catch (e) {
print(e.toString());
return null;
}
}
// sign in with email and password
Future signInWithEmailAndPassword(String email, String password) async {
try {
auth.UserCredential result = await _auth.signInWithEmailAndPassword(
email: email, password: password);
auth.User user = result.user;
print('Successfully logged in, User UID: ${user.uid}');
return user;
} catch (error) {
print(error.toString());
return null;
}
}
// register with email and password
Future registerWithEmailAndPassword(String email, String password) async {
try {
auth.UserCredential result = await _auth.createUserWithEmailAndPassword(
email: email, password: password);
auth.User user = result.user;
// create a new document for the user with the uid
await DatabaseService(uid: user.uid).updateUserData(null);
print('Successfully registered, User UID: ${user.uid}');
return _userFromFirebaseUser(user);
} catch (error) {
print(error.toString());
return null;
}
}
// sign out
Future signOut() async {
try {
print('User signed out');
return await _auth.signOut();
} catch (error) {
print(error.toString());
return null;
}
}
Future<Map<dynamic, dynamic>> get _userClaims async {
final user = _auth.currentUser;
// If refresh is set to true, a refresh of the id token is forced.
final idTokenResult = await user.getIdTokenResult(true);
return idTokenResult.claims;
}
}
Found here: In flutter, how can I "merge" Firebase onAuthStateChanged with user.getTokenId() to return a Stream?
I'd like to block out people who didn't verify their email so i figured out this code for sign up:
// sign up
Future signUp(String email, String password) async {
try {
await _auth.createUserWithEmailAndPassword(
email: email, password: password);
} catch (e) {
print('An error has occured by creating a new user');
print(
e.toString(),
);
}
try {
final FirebaseUser _user = await _auth.currentUser();
await _user.sendEmailVerification();
} catch (error) {
print("An error occured while trying to send email verification");
print(error.toString());
}
try {
await _auth.signOut();
} catch (err) {
print(err);
}
}
and this for sign in:
//Sign In with Email and Pass
Future signInWithEmailAndPassword(String email, String password) async {
FirebaseUser _user = await FirebaseAuth.instance.currentUser();
if (_user != null && _user.isEmailVerified == true) {
try {
await _auth.signInWithEmailAndPassword(
email: email, password: password);
return _user;
} catch (e) {
return null;
}
} else {
return null;
}
}
_auth is just an instance of FirebaseAuth.
The problem is that i can login even if i didnt verify the email.
Firebase Auth doesn't stop accounts from signing in if the user hasn't verified their email address yet. You can check that property _user.isEmailVerified to find out the state of that validation after the user signs in, and you can determine from there what the user should see.
isEmailVerified can be a little bit of trouble to get working correctly.
Make sure you are calling
await FirebaseAuth.instance.currentUser()..reload();
before your are calling isEmailVerified also in my own experience and I don't know if this is just something I was doing wrong but this did not work from my Auth class this did not start working until I put the code directly in initState() of my widget that checks whether the user is verified. Like I said that part might have been something I did wrong. Like stated this will not listen for change you must check yourself either periodically or at a point that you know email is verified.
Future(() async {
_timer = Timer.periodic(Duration(seconds: 10), (timer) async {
await FirebaseAuth.instance.currentUser()
..reload();
var user = await FirebaseAuth.instance.currentUser();
if (user.isEmailVerified) {
timer.cancel();
Navigator.of(context).popAndPushNamed(HearingsScreen.routeName);
}
});
});
So it checks every 10 seconds to see if the user has verified their email not the most elegant solution. The page I have this on just displays a message 'Please verify your email' so its not like this is interrupting other code. If your app is performing other tasks this might not be an option for you. If you want to play around with isEmailVerified go ahead but i spent a week of headaches until i settled on this.
I have a Google authentication working just fine, and I need to create another signUp method (with email/and password), so what are the best approaches for implementing this signUp method?
I tried to create a user and it worked. But then I can't navigate to my other pages!
I couldn't find any good blog posts or documentation. Note that when the user signs up I also need to add them in firebase Database.
Try something like this:
emailPasswordLogin(BuildContext context, String email, String password)async{
try {
AuthResult authResult = await _auth.signInWithEmailAndPassword(
email: email, password: password);
FirebaseUser user = authResult.user;
} catch (ex) {
print("Code: " + ex.code);
switch (ex.code) {
case 'ERROR_USER_NOT_FOUND':
{
await createUser(email, password, context);
}
case 'ERROR_WRONG_PASSWORD':
print("wrong password);
break;
case 'ERROR_INVALID_EMAIL':
print("invalid email")
break;
case 'ERROR_OPERATION_NOT_ALLOWED':
print("Login Method not defined")
break;
case 'ERROR_WEAK_PASSWORD':
print("weak password")
break;
default:
print('Case ${ex.message} is not yet implemented');
}
return;
}
storeData(user, context);
}
storeData(FirebaseUser user, BuildContext context) async {
_database = new FirebaseDatabase();
await _database
.reference()
.child('user')
.push().set(<dynamic, dynamic> async{
"email": user.email,
}).then((_) {
print("Transaction commited");
Navigator.of(context).push(
MaterialPageRoute(builder: (context) => NextPage());
});
}