iOS Gmail Login using google SDK and storing data in Firebase.

This story is a continuation of my previous story here, previous story contains facebook login storing in firebase. This story will discuss Gmail login storing in firebase.

Step 1. Install Google Pods.

pod ‘GoogleSignIn’, ‘5.0’ — This for google login.

pod ‘Firebase/Auth’, ‘6.33.0’ — this for firebase.

Step 2. Add plist from firebase configuration. And the client id setup.

If you follow my previous URL we have download .plist from firebase config, please refer to my previous URL step 5–2.

XCode, you’ll have GoogleService-Info.plist file, open it and find REVERSED_CLIENT_ID, copy it!

Client id Located in plist

Select your app from the TARGETS section, then select the Info tab, and expand the URL Types section, click on + and paste the copied REVERSED_CLIENT_ID here.

Step 3. Write code in the App delegate.

Following code Add-In didFinishLaunchingWithOptions and in open url

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
GIDSignIn.sharedInstance()?.clientID = FirebaseApp.app()?.options.clientID
return true
}

func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
var result = true
result = GIDSignIn.sharedInstance().handle(url)
return result
}

I created ‘googleLoginButton’ is from the UIView object in .xib that looks like below.

This is UIView Object

And I created SignInViewController.swift file looks like below.

import UIKit
import FirebaseAuth
import GoogleSignIn
class SignInViewController: UIViewController {
@IBOutlet weak var googleLoginButton: GIDSignInButton!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
view.backgroundColor = .white
GIDSignIn.sharedInstance()?.presentingViewController = self
GIDSignIn.sharedInstance().delegate = self
configureUI()
}
private func configureUI() {
//if user previously sign launch home
if isUserPreviouslySignInWithGmail() {
// launch what ever we need to show
}
}
//this check if user is previously login.
private func isUserPreviouslySignInWithGmail() -> Bool {
if GIDSignIn.sharedInstance().hasPreviousSignIn() {
return true
}
return false
}
//If user login complete in gmail site follwoing delegate method will get call And storeing user id singin also mentioned in below code.
extension SignInViewController: GIDSignInDelegate {
func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) {
guard let idToken = user?.authentication.idToken, let accessToken = user?.authentication.accessToken else {
print("Failed to log into Google:  \(error.localizedDescription)")
return
}
let credentials = GoogleAuthProvider.credential(withIDToken: idToken, accessToken: accessToken)
loggingWithGmail(credentials: credentials) { [weak self] (error) in
if let error = error {
print("Error logging in firebase \(error.localizedDescription)")
return
}
self?.saveUserInfo()
}
}
}
public func loggingWithGmail(credentials: AuthCredential, completion: @escaping (Error?) -> Void) {
fireBaseSignIn(with: credentials, completion: { [weak self] (data, error) in
guard let result = data, error == nil else {
print("FB Login Error: \(String(describing: error?.localizedDescription))")
completion(error)
return
}
completion(nil)
self?.saveUserInfo(authData: result)
})
}
//storing into firebase
private func fireBaseSignIn(with credentials: AuthCredential, completion: @escaping (AuthDataResult?, Error?) -> Void) {
Auth.auth().signIn(with: credentials) { (result, error) in
guard let dataResult = result else {
completion(nil, error)
print("Firebase login error ")
return
}
completion(dataResult, nil)
}
}
/// Save user info to User Defaults
private func saveUserInfo(authData: AuthDataResult) {
let userDefaults = UserDefaults.standard
let _ = authData.user.photoURL
userDefaults.setValue(authData.user.displayName, forKey: "name")
}

With help of the following URLs, this one is written, please add in comments if you need any help on this. And please clap if you like this.

https://developers.google.com/identity/sign-in/ios/start-integrating