Firebase Exceptions handling on create user by email

Question

How to handle errors in the new Firebase sdk for authentication? In the previous versions i can find the OnAuthenticationError method and it gives FirebaseException error but in the new verison i dont see such method. Lets say i create a user by email password,for some reason exception occurs . The only way i can see to grab this exception is the task.getException.getMessage() and with this message i check for various error messages and then in turn get the error which occured. Please suggest a better method or correct me if i m missing something

Answer 1

The main exceptions:

firebaseAuth.createUserWithEmailAndPassword(email, pass )
      .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
           @Override
           public void onComplete(@NonNull Task<AuthResult> task) {
           if(task.isSuccessful())
               {
                 //--If success        
 }else if (task.getException() instanceof FirebaseAuthUserCollisionException) 
 {                           
     //If email already registered.

 }else if (task.getException() instanceof FirebaseAuthInvalidCredentialsException) {
     //If email are in incorret  format    

 }else if (task.getException() instanceof FirebaseAuthWeakPasswordException) {
        //if password not 'stronger'                    
 }else
 {
    //OTHER THING
 }
}
});

Answer 2

In the new Firebase a lot of methods return a so-called Task. If you've used promises in JavaScript before, you'll find they're very similar.

On the task, you can get a few callbacks:

• a success listener, which gets invoked once the task succeeds
• a failure listener, which gets invoked once the task fails
• a completion listener, which gets invoked once the task completes (successfully or not)

In your case you're looking for a failure in creating a user, so:

auth.createUserWithEmailAndPassword(email, password)
    .addOnFailureListener(new OnFailureListener() {
        public void onFailure(@NonNull Exception e) {
            Log.e(TAG, "Unable to create user", e);
        }
    });

The exception will be a subclass of FirebaseAuthException, which means you can call getErrorCode() on it. This returns an error code. It's indeed a string, but of a form auth/error which can be easily captured in a switch case.

Also see the documentation on creating a user for a sample that uses a completion listener.