Platform
Sign Up With Apple

15min
Sign In with Apple Tutorial
Introduction
Sign In with Apple enables users to sign in to Apps using their Apple ID.
This feature is available on iOS 13 and later, and Parse 3.5 and later.
Prerequisites
To complete this tutorial, you will need:
An app created at Back4App
See the Create New App tutorial to learn how to create an app at Back4App.
Set up a Subdomain for your Back4app app
See Activating your Web Hosting and Live Query to learn how to create a subdomain in Back4App.
An Apple Developer account.
- Create a New Back4App App
First of all, it’s necessary to make sure that you have an existing app created at Back4App. However, if you are a new user, you can check this tutorial to learn how to create one.
- Add the Sign In with Apple capability to your XCode project
In your XCode Project, click on the Target (1) and go to the Signing & Capabilities tab (2).
Click the + Capability button (3) and add the Sign In with Apple capability (4).
While there, choose your Bundle Identifier (5) and hold that information because we will need it later.
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- Create a new Service ID
Log into your Apple Developer account and go to the Identifiers section. Check if your created Bundle Identifier is there
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Click the Bundle Identifier and scroll down. Check if the Sign In with Apple is selected
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Click Edit and make sure the Enable as a primary App ID is selected
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If everything is right, save and exit.
- Set up Parse Auth for Apple
Go to the Back4App website, log in, and then find your app. After that, click on Server Settings search for the Apple Login block, and select Settings.
The Apple Login section looks like this:
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Now, you just need to paste your Bundle ID in the field below and click on the button to save.
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In case you face any trouble while integrating Apple Login, please contact our team via chat!
- Option 1 - Download our Template
There is some coding involved in making Sign in With Apple work, so we created this template that you can download, and change the Bundle Identifier, the App Id, and Client Key.
The code is fully documented so it is a good starting point.
If you prefer to read through this doc, please go on to the next step.
- Option 2 - Manually write code
Inside your view, add the AuthenticationServices framework and create the AuthDelegate that will handle the PFUserAuthenticationDelegate:
Swift
 import AuthenticationServices
2
 class AuthDelegate:NSObject, PFUserAuthenticationDelegate {
     func restoreAuthentication(withAuthData authData: [String : String]?) -> Bool {
         return true
     }
  
     func restoreAuthenticationWithAuthData(authData: [String : String]?) -> Bool {
         return true
    }
}
 import AuthenticationServices
2
 class AuthDelegate:NSObject, PFUserAuthenticationDelegate {
     func restoreAuthentication(withAuthData authData: [String : String]?) -> Bool {
         return true
     }
  
     func restoreAuthenticationWithAuthData(authData: [String : String]?) -> Bool {
         return true
    }
}
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- Implement your Delegates for the ViewController
Implement the ASAuthorizationControllerDelegate and ASAuthorizationControllerPresentationContextProviding for the ViewController:
Swift
 class ViewController: UIViewController, ASAuthorizationControllerDelegate, ASAuthorizationControllerPresentationContextProviding
 class ViewController: UIViewController, ASAuthorizationControllerDelegate, ASAuthorizationControllerPresentationContextProviding
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- Add the Sign In with Apple button
The ViewDidAppear is a good place for it. If you choose other places, remember to call it just once:
Swift
 override func viewDidAppear(_ animated: Bool) {
         super.viewDidAppear(animated)
      
         // Sign In with Apple button
         let signInWithAppleButton = ASAuthorizationAppleIDButton()
6
         // set this so the button will use auto layout constraint
         signInWithAppleButton.translatesAutoresizingMaskIntoConstraints = false
9
        // add the button to the view controller root view
        self.view.addSubview(signInWithAppleButton)
12
        // set constraint
        NSLayoutConstraint.activate([
            signInWithAppleButton.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor, constant: 50.0),
            signInWithAppleButton.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor, constant: -50.0),
            signInWithAppleButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -70.0),
            signInWithAppleButton.heightAnchor.constraint(equalToConstant: 50.0)
        ])
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        // the function that will be executed when user tap the button
        signInWithAppleButton.addTarget(self, action: #selector(appleSignInTapped), for: .touchUpInside)
    }
 override func viewDidAppear(_ animated: Bool) {
         super.viewDidAppear(animated)
      
         // Sign In with Apple button
         let signInWithAppleButton = ASAuthorizationAppleIDButton()
6
         // set this so the button will use auto layout constraint
         signInWithAppleButton.translatesAutoresizingMaskIntoConstraints = false
9
        // add the button to the view controller root view
        self.view.addSubview(signInWithAppleButton)
12
        // set constraint
        NSLayoutConstraint.activate([
            signInWithAppleButton.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor, constant: 50.0),
            signInWithAppleButton.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor, constant: -50.0),
            signInWithAppleButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -70.0),
            signInWithAppleButton.heightAnchor.constraint(equalToConstant: 50.0)
        ])
20
        // the function that will be executed when user tap the button
        signInWithAppleButton.addTarget(self, action: #selector(appleSignInTapped), for: .touchUpInside)
    }
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The appleSignInTapped in the last line must also be defined inside the ViewController class:
Swift
// This is the function that will be executed when user taps the button
     @objc func appleSignInTapped() {
         let provider = ASAuthorizationAppleIDProvider()
         let request = provider.createRequest()
         // request full name and email from the user's Apple ID
         request.requestedScopes = [.fullName, .email]
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         // pass the request to the initializer of the controller
         let authController = ASAuthorizationController(authorizationRequests: [request])
      
        // similar to delegate, this will ask the view controller
        // which window to present the ASAuthorizationController
        authController.presentationContextProvider = self
      
        // delegate functions will be called when user data is
        // successfully retrieved or error occured
        authController.delegate = self
        
        // show the Sign-in with Apple dialog
        authController.performRequests()
    }
// This is the function that will be executed when user taps the button
     @objc func appleSignInTapped() {
         let provider = ASAuthorizationAppleIDProvider()
         let request = provider.createRequest()
         // request full name and email from the user's Apple ID
         request.requestedScopes = [.fullName, .email]
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         // pass the request to the initializer of the controller
         let authController = ASAuthorizationController(authorizationRequests: [request])
      
        // similar to delegate, this will ask the view controller
        // which window to present the ASAuthorizationController
        authController.presentationContextProvider = self
      
        // delegate functions will be called when user data is
        // successfully retrieved or error occured
        authController.delegate = self
        
        // show the Sign-in with Apple dialog
        authController.performRequests()
    }
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- The presentationContextProvider
The presentationContextProvider (ASAuthorizationControllerPresentationContextProviding) will ask for which window should display the Authorization dialog. As we are going to display it in the same window, we must return self.view.window:
Swift
 func presentationAnchor(for controller: ASAuthorizationController) -> ASPresentationAnchor {
         // return the current view window
         return self.view.window!
     }
 func presentationAnchor(for controller: ASAuthorizationController) -> ASPresentationAnchor {
         // return the current view window
         return self.view.window!
     }
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- Handling the delegate ASAuthorizationControllerDelegate
There are a few options that we must handle when the delegate is called, so let’s add some code to handle those options distinctly:
Swift
 func authorizationController(controller: ASAuthorizationController, didCompleteWithError error: Error) {
         print("authorization error")
         guard let error = error as? ASAuthorizationError else {
             return
         }
6
         switch error.code {
         case .canceled:
             // user press "cancel" during the login prompt
            print("Canceled")
        case .unknown:
            // user didn't login their Apple ID on the device
           print("Unknown")
        case .invalidResponse:
            // invalid response received from the login
            print("Invalid Respone")
        case .notHandled:
            // authorization request not handled, maybe internet failure during login
            print("Not handled")
        case .failed:
            // authorization failed
            print("Failed")
        @unknown default:
            print("Default")
        }
    }
 func authorizationController(controller: ASAuthorizationController, didCompleteWithError error: Error) {
         print("authorization error")
         guard let error = error as? ASAuthorizationError else {
             return
         }
6
         switch error.code {
         case .canceled:
             // user press "cancel" during the login prompt
            print("Canceled")
        case .unknown:
            // user didn't login their Apple ID on the device
           print("Unknown")
        case .invalidResponse:
            // invalid response received from the login
            print("Invalid Respone")
        case .notHandled:
            // authorization request not handled, maybe internet failure during login
            print("Not handled")
        case .failed:
            // authorization failed
            print("Failed")
        @unknown default:
            print("Default")
        }
    }
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- Handling the delegate for didCompleteWithAuthorization
When we successfully authenticate, we can retrieve the authorized information:
Swift
    func authorizationController(controller: ASAuthorizationController, didCompleteWithAuthorization authorization: ASAuthorization) {
      
            if let appleIDCredential = authorization.credential as? ASAuthorizationAppleIDCredential {
                // unique ID for each user, this uniqueID will always be returned
                let userID = appleIDCredential.user
                print("UserID: " + userID)
          
                // if needed, save it to user defaults by uncommenting the line below
                //UserDefaults.standard.set(appleIDCredential.user, forKey: "userID")
          
               // optional, might be nil
               let email = appleIDCredential.email
               print("Email: " + (email ?? "no email") )
          
               // optional, might be nil
               let givenName = appleIDCredential.fullName?.givenName
               print("Given Name: " + (givenName ?? "no given name") )
          
               // optional, might be nil
               let familyName = appleIDCredential.fullName?.familyName
               print("Family Name: " + (familyName ?? "no family name") )
          
               // optional, might be nil
               let nickName = appleIDCredential.fullName?.nickname
               print("Nick Name: " + (nickName ?? "no nick name") )
               /*
                   useful for server side, the app can send identityToken and authorizationCode
                   to the server for verification purpose
               */
               var identityToken : String?
               if let token = appleIDCredential.identityToken {
                   identityToken = String(bytes: token, encoding: .utf8)
                   print("Identity Token: " + (identityToken ?? "no identity token"))
               }
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               var authorizationCode : String?
               if let code = appleIDCredential.authorizationCode {
                   authorizationCode = String(bytes: code, encoding: .utf8)
                   print("Authorization Code: " + (authorizationCode ?? "no auth code") )
               }
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               // do what you want with the data here
          
         }    
     }
    func authorizationController(controller: ASAuthorizationController, didCompleteWithAuthorization authorization: ASAuthorization) {
      
            if let appleIDCredential = authorization.credential as? ASAuthorizationAppleIDCredential {
                // unique ID for each user, this uniqueID will always be returned
                let userID = appleIDCredential.user
                print("UserID: " + userID)
          
                // if needed, save it to user defaults by uncommenting the line below
                //UserDefaults.standard.set(appleIDCredential.user, forKey: "userID")
          
               // optional, might be nil
               let email = appleIDCredential.email
               print("Email: " + (email ?? "no email") )
          
               // optional, might be nil
               let givenName = appleIDCredential.fullName?.givenName
               print("Given Name: " + (givenName ?? "no given name") )
          
               // optional, might be nil
               let familyName = appleIDCredential.fullName?.familyName
               print("Family Name: " + (familyName ?? "no family name") )
          
               // optional, might be nil
               let nickName = appleIDCredential.fullName?.nickname
               print("Nick Name: " + (nickName ?? "no nick name") )
               /*
                   useful for server side, the app can send identityToken and authorizationCode
                   to the server for verification purpose
               */
               var identityToken : String?
               if let token = appleIDCredential.identityToken {
                   identityToken = String(bytes: token, encoding: .utf8)
                   print("Identity Token: " + (identityToken ?? "no identity token"))
               }
35
               var authorizationCode : String?
               if let code = appleIDCredential.authorizationCode {
                   authorizationCode = String(bytes: code, encoding: .utf8)
                   print("Authorization Code: " + (authorizationCode ?? "no auth code") )
               }
41
               // do what you want with the data here
          
         }    
     }
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That’s the place where we can also add code for logging in Parse. So right after the do what you want with the data here comment, let’s add:
Swift
 PFUser.logInWithAuthType(inBackground: "apple", authData: ["token": String(identityToken!), "id": userID]).continueWith { task -> Any? in
                 if ((task.error) != nil){
                     //DispatchQueue.main.async {
                         print("Could not login.\nPlease try again.")
                         print("Error with parse login after SIWA: \(task.error!.localizedDescription)")
                     //}
                     return task
                 }
                 print("Successfuly signed in with Apple")
                return nil
            }
 PFUser.logInWithAuthType(inBackground: "apple", authData: ["token": String(identityToken!), "id": userID]).continueWith { task -> Any? in
                 if ((task.error) != nil){
                     //DispatchQueue.main.async {
                         print("Could not login.\nPlease try again.")
                         print("Error with parse login after SIWA: \(task.error!.localizedDescription)")
                     //}
                     return task
                 }
                 print("Successfuly signed in with Apple")
                return nil
            }
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And of course, add the Parse framework:
Swift
 import Parse
 import Parse
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