Firebase phone Authenication iOS - ios

Question

I am currently authenticating users using firebase phone Authentication and it works fine, however when I close the app and open it again I am redirected to the Authentication form and I receive an authentication Code each time. I don't want that kind of behavior. Is there is a way to check if the current user or the phone number is already authenticated without saving the user to a database

Answer 1

You can do it like checking for the currentUser in firebase, if the currentUser's phone number is same as the provided phone number in textField, then you can bypass the authentication and take user to home screen. Here is how it can be done.
if Auth.auth().currentUser != nil {
// USER IS SIGNED IN, BUT STILL WE HAVE TO CHECK, IF THE SAME USER IS SIGNING IN OR DIFFERENT.
if let user = Auth.auth().currentUser {
let phone = user.phone
if phone == YOUR TEXTFIELD VALUE OF PHONE {
// YOU HAVE THE LOGGED IN USER NOW, YOU CAN TAKE USER TO HOME SCREEN
} else {
// SIGNOUT THE CURRENT USER AND DO THE AUTHENTICATION FOR NEW USER
let firebaseAuth = Auth.auth()
do {
try firebaseAuth.signOut()
} catch let signOutError as NSError {
print ("Error signing out: %#", signOutError)
}
// No USER IS SIGNED IN, SO GET CREDENTIAL FROM YOUR SERVER AND SEND IT TO AUTH
Auth.auth().signIn(withCustomToken: customToken ?? "") { (user, error) in
// YOU HAVE THE LOGGED IN USER NOW, YOU CAN TAKE USER TO HOME SCREEN
}
}
}
} else {
// No USER IS SIGNED IN, SO GET CREDENTIAL FROM YOUR SERVER AND SEND IT TO AUTH
Auth.auth().signIn(withCustomToken: customToken ?? "") { (user, error) in
// YOU HAVE THE LOGGED IN USER NOW, YOU CAN TAKE USER TO HOME SCREEN
}
}
Check the procedure, if this is what you wants to achieve.