Flutter: Firebase authentication create user without logging In - firebase

Question

I have a user management feature in my flutter app that uses firebase authentication. I can register new user accounts using firebase_auth's createUserWithEmailAndPassword() function.
return await FirebaseAuth.instance.
createUserWithEmailAndPassword(email: email, password: password);
The problem is when the registration is successful it automatically authenticates my FirebaseAuth instance as the new user even though I am already logged in.
I came across this answer: Firebase kicks out current user but it's in javascript and has a slightly different api.
How can I do the equivalent in dart?

Answer 1

Updated: firebase_core ^0.5.0 and firebase_auth ^0.18.0+1 has deprecated some of the old classes.
Below is code updated for firebase_core ^0.5.1 and firebase_auth ^0.18.2.
static Future<UserCredential> register(String email, String password) async {
FirebaseApp app = await Firebase.initializeApp(
name: 'Secondary', options: Firebase.app().options);
try {
UserCredential userCredential = await FirebaseAuth.instanceFor(app: app)
.createUserWithEmailAndPassword(email: email, password: password);
}
on FirebaseAuthException catch (e) {
// Do something with exception. This try/catch is here to make sure
// that even if the user creation fails, app.delete() runs, if is not,
// next time Firebase.initializeApp() will fail as the previous one was
// not deleted.
}
await app.delete();
return Future.sync(() => userCredential);
}
Original Answer
I experimented with the firebase authentication api and my current working solution is:
// Deprecated as of `firebase_core ^0.5.0` and `firebase_auth ^0.18.0`.
// Use code above instead.
static Future<FirebaseUser> register(String email, String password) async {
FirebaseApp app = await FirebaseApp.configure(
name: 'Secondary', options: await FirebaseApp.instance.options);
return FirebaseAuth.fromApp(app)
.createUserWithEmailAndPassword(email: email, password: password);
}
Essentially it comes down to creating a new instance of FirebaseAuth so the automatic login from createUserWithEmailAndPassword() do not affect the default instance.

Answer 2

Based on Swift's answer I post updated code for this work around.
Future signUpWithEmailPasswordAdminPastor(String email, String password, String role, String nama, String keuskupan, String kevikepan, String paroki) async {
try {
FirebaseApp tempApp = await Firebase.initializeApp(name: 'temporaryregister', options: Firebase.app().options);
UserCredential result = await FirebaseAuth.instanceFor(app: tempApp).createUserWithEmailAndPassword(
email: email, password: password);
// create a new document user for the user with uid
await DatabaseService(uid: result.user.uid).updateUserDataSelf(
true,
role,
nama,
keuskupan,
kevikepan,
paroki,
'',
DateTime.now(),
DateTime.now());
tempApp.delete();
return 'OK';
} catch (e) {
print(e.toString());
return null;
}
}
Above code works for firebase_core: ^0.5.0 and firebase_auth: ^0.18.0+1.