How does Firebase Auth UI deal with reauthentication?

Question

I\'m using Firebase Auth for my Swift iOS app. Google recommends using Firebase Auth UI as a \"drop in\" authentication system, but it only handles the initial login. I\'m n

Answer 1

Regarding the error code, the documentation just needs updating. The error code is now called FIRAuthErrorCode.errorCodeRequiresRecentLogin.

Now, as of the UI problem you're facing, why not just present a UIAlertController with a text field that the users can use to enter their passwords for re-authentication? It's certainly much simpler (and user-friendlier) than creating an entire view controller.

Here's a pretty straightforward sample of how you can re-authenticate your users without going through so much trouble:

// initialize the UIAlertController for password confirmation
let alert = UIAlertController(title: "", message: "Please, enter your password:", preferredStyle: UIAlertControllerStyle.alert)
// add text field to the alert controller
alert.addTextField(configurationHandler: { (textField) in
    textField.placeholder = "Password"
    textField.autocapitalizationType = .none
    textField.autocorrectionType = .no
    textField.isSecureTextEntry = true
})
// delete button action
alert.addAction(UIAlertAction(title: "Delete account", style: UIAlertActionStyle.destructive, handler: {action in
    // retrieve textfield
    let txtFld = alert.textFields![0]
    // init the credentials (assuming you're using email/password authentication
    let credential = FIREmailPasswordAuthProvider.credential(withEmail: (FIRAuth.auth()?.currentUser?.email)!, password: txtFld.text!)
    FIRAuth.auth()?.currentUser?.reauthenticate(with: credential, completion: { (error) in
        if error != nil {
            // handle error - incorrect password entered is a possibility
            return
        }

        // reauthentication succeeded!
    })
}))
// cancel reauthentication
alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.cancel, handler: {action in }))

// finally, present the alert controller
self.present(alert, animated: true, completion: nil)

Whenever you need to change the user's email or delete their account (password reset doesn't require a login at all), use the snippet above to just pop up an alert controller where they can re-enter their password.

EDIT: Please note that the code provided above force-unwraps the current user's email, so make sure you have a user logged-in at that stage or your app will crash.