How to handle firebase auth errors?

[riccardoratta]

I'm trying to build a login page with firebase auth plugin. But I don't know how to handle auth errors in a cross-platform way. For example, this are some PlatformException that I get when the user type the wrong password/email or there are a network issue.

On iOS:

PlatformException(Error 17011, FIRAuthErrorDomain, There is no user record corresponding to this identifier. The user may have been deleted.)

PlatformException(Error 17009, FIRAuthErrorDomain, The password is invalid or the user does not have a password.)

PlatformException(Error 17020, FIRAuthErrorDomain, Network error (such as timeout, interrupted connection or unreachable host) has occurred.)

On Android:

PlatformException(exception, There is no user record corresponding to this identifier. The user may have been deleted., null)

PlatformException(exception, The password is invalid or the user does not have a password., null)

PlatformException(exception, A network error (such as timeout, interrupted connection or unreachable host) has occurred., null)

The format is: code, message, details. In Android I get a code: exception, what does it mean? And also in iOS I always get a message: FIRAuthErrorDomain and not any standard code listed here.

The code:

try {
    _user = await _auth.signInWithEmailAndPassword(
        email: _email,
        password: _password);
} on PlatformException catch (e) {
    print(e);
}

Temporary fix (don't rely on this solution)

In the meantime the problem can be fixed (see bottom for warning on this solution) with something like that:

enum authProblems { UserNotFound, PasswordNotValid, NetworkError }

authProblems errorType;
if (Platform.isAndroid) {
  switch (e.message) {
    case 'There is no user record corresponding to this identifier. The user may have been deleted.':
      errorType = authProblems.UserNotFound;
      break;
    case 'The password is invalid or the user does not have a password.':
      errorType = authProblems.PasswordNotValid;
      break;
    case 'A network error (such as timeout, interrupted connection or unreachable host) has occurred.':
      errorType = authProblems.NetworkError;
      break;
    // ...
    default:
      print('Case ${e.message} is not jet implemented');
  }
} else if (Platform.isIOS) {
  switch (e.code) {
    case 'Error 17011':
      errorType = authProblems.UserNotFound;
      break;
    case 'Error 17009':
      errorType = authProblems.PasswordNotValid;
      break;
    case 'Error 17020':
      errorType = authProblems.NetworkError;
      break;
    // ...
    default:
      print('Case ${e.message} is not jet implemented');
  }
}
print('The error is $errorType');

Warning: The problem, that I would like to emphasize with this issue, it's that you can't rely too much in this solution because a simple FirebaseAuth update can screw it up. Also if you choose this way be sure to lock the firebase_auth: ?.?.? to a specific version in the pubspec.yaml file.

---

Flutter doctor

[✓] Flutter (Channel beta, v0.5.1, on Mac OS X 10.13.6 17G65, locale en-IT)
    • Flutter version 0.5.1 at /Users/.../Library/flutter
    • Framework revision c7ea3ca377 (10 weeks ago), 2018-05-29 21:07:33 +0200
    • Engine revision 1ed25ca7b7
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[✓] Android toolchain - develop for Android devices (Android SDK 27.0.3)
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    • Platform android-27, build-tools 27.0.3
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    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)
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[zoechi]

Similar to #18312, #13027

[joshkendrick]

i think this issue is the appropriate spot...
i'm seeing

PlatformException(exception, The sms verification code used to create the phone auth credential is invalid. Please resend the verification code sms and be sure use the verification code provided by the user., null)

if a user enters the wrong SMS code when doing phone number auth -- it looks like this this may be getting addressed in flutter/plugins#678 if it's similar to #18312 ?

[slightfoot]

@joshkendrick My upcoming patch will address this. and #18312

[joshkendrick]

sounds great!

[eturk1]

@joshkendrick My upcoming patch will address this. and #18312

@joshkendrick , will your update allow us to catch all Firebase exceptions that currently can't be handled?
(I see many several issues posted about exceptions not handle but only you seem to be addressing it)

[HerrNiklasRaab]

Is there any hack, to identify the errors correctly in android? Because now the error code is not provided. :(

[ghost]

As @HerrNiklasRaab said now it returns this PlatformException(sign_in_failed, FIRAuthErrorDomain, The email address is badly formatted.) how to handle properly?
It used to return specific code but now every errors return sign_in_failed as long as it is about sign in.

[knitero]

Stuck with the same issue. Any work around?

[anderscheow]

Any update on this? I need error code to display custom error message

[suparnavg]

+1.. this is a core part of the firebase auth experience. Really difficult to release an app into the wild where all sorts of auth errors might crop up. The PlatformException thrown freezes up the whole app and makes it unusable until a recompile..

[riccardoratta]

@suparnavg Sorry why you are saying that this auth errors freezes up the app and it's not unusable until a recompile? In the code that I've included it doesn't happen. You are maybe forgetting the try {} catch (e) {} statement? If not can you give a more detailed example?

[riccardoratta]

@knitero @anderscheow @HerrNiklasRaab See the updated question for a temporary solution.

[HerrNiklasRaab]

@riccardoratta Thanks, this is bad, but the best possible solution :)

[anderscheow]

@riccardoratta The solution you proposed is what I wanted to prevent :(

[riccardoratta]

@anderscheow Yes, it's the point of the issue. We need a cross platform way (for example by an enum) to know exactly what kind of error firebase auth is throwing. The temporary fix I've included is if you have an application that need to be publicated as soon as possible and you don't know how to proceed.

[slightfoot]

My fix will be merged soon and this can be resolved.

[anderscheow]

Is the fix release?

[suparnavg]

Thanks @riccardoratta will give it a shot. My comment was meant for the original question, not your solution :)

[JonasJW]

Is there meanwhile a solution to this problem?

I need to something like this:

    try {
      await _auth.createUserWithEmailAndPassword(email: email, password: password);
      return 0;
    } catch (error) {
      return error;
    }

So I can distinguish the errors but I could find any solution to this.

[markflarup]

My fix will be merged soon and this can be resolved.

Any updates on this?

[zoechi]

@markflarup

This issue is closed.

@slightfoot slightfoot closed this in flutter/plugins#775 on 22 Nov 2018

[ra7bi]

You can do

    try {
      //
    }on PlatformException catch (error)  { 
       List<String> errors = error.toString().split(',');
      print("Error: " + errors[1]); 
    }

You will get the error only like

The email address is badly formatted

[mikecbone]

On Android, you can grab the code from the exception. I can't test on iOS atm but is there a reason not to use this?

catch (e) {
  print(e.code);
  switch (e.code) {
    case 'ERROR_INVALID_EMAIL':
      authError = 'Invalid Email';
      break;
    case 'ERROR_USER_NOT_FOUND':
      authError = 'User Not Found';
      break;
    case 'ERROR_WRONG_PASSWORD':
      authError = 'Wrong Password';
      break;
    default:
      authError = 'Error';
      break;
  }
}

[slightfoot]

I implemented the error handling. You do not want to use error.toString() rather as @mikecbone said. Check the code if you want some specific behaviour when an error occurs then you can show a widget or take the user to a specific screen. If you want to display the friendly message. Then you can use error.message, or as @mikecbone has done so you can app specific messages perhaps, or custom localised versions.

https://api.flutter.dev/flutter/services/PlatformException-class.html

[marcelino-borges]

On Android, you can grab the code from the exception. I can't test on iOS atm but is there a reason not to use this?

catch (e) {
  print(e.code);
  switch (e.code) {
    case 'ERROR_INVALID_EMAIL':
      authError = 'Invalid Email';
      break;
    case 'ERROR_USER_NOT_FOUND':
      authError = 'User Not Found';
      break;
    case 'ERROR_WRONG_PASSWORD':
      authError = 'Wrong Password';
      break;
    default:
      authError = 'Error';
      break;
  }
}

@mikecbone, where can we find all these existing error messages? Firebase official docs don't have it... And i can't find anywhere...

[mikecbone]

@mikecbone, where can we find all these existing error messages? Firebase official docs don't have it... And i can't find anywhere...

You can find a list of errors here. You just need to replace FIRAuthErrorCode with ERROR and then stick an underline between each word.

So FIRAuthErrorCodeUserNotFound becomes ERROR_USER_NOT_FOUND

Not the best solution I know, but it does seem to work.

[marcelino-borges]

Oh boy, so that's the secret... Thank you!

[slightfoot]

I documented the error codes in the source on each one of the FirebaseAuth functions.

For example: https://github.com/flutter/plugins/blob/master/packages/firebase_auth/lib/src/firebase_auth.dart#L204

So just check the function comments you are calling.

[marcelino-borges]

@slightfoot

I'll check it out! Thank you!

[TxusBlack]

I documented the error codes in the source on each one of the FirebaseAuth functions.

For example: https://github.com/flutter/plugins/blob/master/packages/firebase_auth/lib/src/firebase_auth.dart#L204

So just check the function comments you are calling.

Error 404

[marcelino-borges]

I documented the error codes in the source on each one of the FirebaseAuth functions.
For example: https://github.com/flutter/plugins/blob/master/packages/firebase_auth/lib/src/firebase_auth.dart#L204
So just check the function comments you are calling.

Error 404

Indeed

[gcamp806]

Found it - https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_auth/lib/src/firebase_auth.dart#L204

[TxusBlack]

Found it - https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_auth/lib/src/firebase_auth.dart#L204

Thanks! 😄

[kroikie]

@riccardoratta

This issue has been moved to firebase/flutterfire#725. Any further collaboration will be done there.

[nikhilmufc7]

I made a gist with all the auth errors from firebase with an example https://gist.github.com/nikhilmufc7/6b74a3c12a6e2d3284942d40ff583e37

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.