Firebase Login Persistence Swift - swift

Question

I'm using Firebase to handle my user register and login for my app. But if I log in, and then close my app entirely - the user is forced to re-log in. I'd like to keep the user logged in unless they click "Log out"
My login code is this:
Auth.auth().signIn(withEmail: email, password: password, completion: {(user, error) in
if let firebaseError = error {
print(firebaseError.localizedDescription)
return
}
self.presentTabBar()
})
}
}
How do I keep this user logged in unless specifically told to logout?

Answer 1

Here's a handy full example for 2020:
Anywhere in your iOS+Firebase app, you can simply say:
guard let uid = Auth.auth().currentUser?.uid else {
return print("no current user!")
}
Thus, on the launch screen of your app, simply:
import UIKit
import Firebase
import FirebaseUI
class ViewController: UIViewController, FUIAuthDelegate {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
guard let uid = Auth.auth().currentUser?.uid else {
return print("no current user, hence AuthUI flow...")
basicAuthUIFlow()
}
print("User .. \(Auth.auth().currentUser?.displayName)")
continueWhenUserPresent()
}
It's that easy. So then as usual ...
private func basicAuthUIFlow() {
let authUI = FUIAuth.defaultAuthUI()
authUI?.delegate = self
let pp: [FUIAuthProvider] = [ FUIGoogleAuth() ]
authUI?.providers = pp
if let authVC = authUI?.authViewController() {
present(authVC, animated: true)
}
}
func authUI(_ authUI: FUIAuth,
didSignInWith authDataResult: AuthDataResult?,url: URL?, error: Error?) {
let u = authDataResult?.user
print("Successful login via authUI \(String(describing: u?.displayName))")
continueWhenUserPresent()
}
private func continueWhenUserPresent() {
.. pushViewController .. your first screen
}

Answer 2

Check if the user is logged in or not:
if Auth.auth().currentUser != nil {
// User is signed in.
// ...
} else {
// No user is signed in.
// ...
}
if the user is logged in, then go the Home ViewController. This way when he opens the app again he will go to the Home ViewController unless he sign outsFIRAuth.auth().signOut()
For more info check this: https://firebase.google.com/docs/auth/ios/manage-users

Answer 3

For keep user login you need to check currentUser Auth session, If it's not nil then you can redirect user to Home screen.
Call "setRootViewController" method from didFinishLaunchingWithOptions, just after FirebaseApp.configure() code
Swift 4
func setRootViewController() {
if Auth.auth().currentUser != nil {
// Set Your home view controller Here as root View Controller
self.presentTabBar()
} else {
// Set you login view controller here as root view controller
}
}