Authenticate Using Twitter and Unity

You can let your users authenticate with Firebase using their Twitter accounts by integrating Sign in with Twitter into your app.

Before you begin

Before you can use the Firebase Authentication, you will need to create a Firebase project, and add the Firebase Unity SDK packages to your Unity project.

Setup:

Prerequisites

If you don't have a Unity project already, you can download one of our quickstart samples and experiment with a specific Firebase feature. If you're using a quickstart, remember to get the bundle identifier from the project settings; you need it for the next step.

Set up your app in the Firebase console

To add Firebase to your app, you need a Firebase project and a Firebase configuration file for your app.

To create a Firebase project:

1. Create a Firebase project in the Firebase console, if you don't already have one. Click Add project. If you already have an existing Google project associated with your mobile app, select it from the Project name drop down menu. Otherwise, enter a project name to create a new project.
2. Optional: Edit your Project ID. Your project is given a unique ID automatically, and it's used in publicly visible Firebase features such as database URLs and your Firebase Hosting subdomain. You can change it now if you want to use a specific subdomain.
3. Follow the remaining setup steps and click Create project (or Add Firebase if you're using an existing project) to begin provisioning resources for your project. This typically takes a few minutes. When the process completes, you'll be taken to the project overview.

Add the Firebase Unity SDK to your app

1. Download the Firebase Unity SDK.
2. Select the Assets > Import Package > Custom Package menu item.
3. Import the FirebaseAuth.unitypackage package from the Firebase Unity SDK, downloaded previously.
4. When the Import Unity Package window appears, click the Import button.

Initialize the SDK

The Firebase Unity SDK on Android requires Google Play services, which must be up-to-date before the SDK can be used. The following code should be added at the start of your application to check for and optionally update Google Play services to the version required by the Firebase Unity SDK before calling any other methods in the SDK.

Firebase.FirebaseApp.CheckAndFixDependenciesAsync().ContinueWith(task => {
  var dependencyStatus = task.Result;
  if (dependencyStatus == Firebase.DependencyStatus.Available) {
    // Set a flag here indiciating that Firebase is ready to use by your
    // application.
  } else {
    UnityEngine.Debug.LogError(System.String.Format(
      "Could not resolve all Firebase dependencies: {0}", dependencyStatus));
    // Firebase Unity SDK is not safe to use here.
  }
});

Build your app

Access the Firebase.Auth.FirebaseAuth class

The FirebaseAuth class is the gateway for all API calls. It is accessable through FirebaseAuth.DefaultInstance.

Firebase.Auth.FirebaseAuth auth = Firebase.Auth.FirebaseAuth.DefaultInstance;

Authenticate with Firebase

1. Follow instructions for Android and iOS to get an OAuth access token and an OAuth secret.
2. After a user successfully signs in, exchange the access token for a Firebase credential, and authenticate with Firebase using the Firebase credential:

   Firebase.Auth.Credential credential =
       Firebase.Auth.TwitterAuthProvider.GetCredential(accessToken, secret);
   auth.SignInWithCredentialAsync(credential).ContinueWith(task => {
     if (task.IsCanceled) {
       Debug.LogError("SignInWithCredentialAsync was canceled.");
       return;
     }
     if (task.IsFaulted) {
       Debug.LogError("SignInWithCredentialAsync encountered an error: " + task.Exception);
       return;
     }
   
     Firebase.Auth.FirebaseUser newUser = task.Result;
     Debug.LogFormat("User signed in successfully: {0} ({1})",
         newUser.DisplayName, newUser.UserId);
   });
   

Next Steps

After a user signs in for the first time, a new user account is created and linked to the credentials—that is, the user name and password, phone number, or auth provider information—the user signed in with. This new account is stored as part of your Firebase project, and can be used to identify a user across every app in your project, regardless of how the user signs in.

• In your apps, you can get the user's basic profile information from the Firebase.Auth.FirebaseUser object:

  Firebase.Auth.FirebaseUser user = auth.CurrentUser;
  if (user != null) {
    string name = user.DisplayName;
    string email = user.Email;
    System.Uri photo_url = user.PhotoUrl;
    // The user's Id, unique to the Firebase project.
    // Do NOT use this value to authenticate with your backend server, if you
    // have one; use User.TokenAsync() instead.
    string uid = user.UserId;
  }
  

• In your Firebase Realtime Database and Cloud Storage Security Rules, you can get the signed-in user's unique user ID from the auth variable, and use it to control what data a user can access.

You can allow users to sign in to your app using multiple authentication providers by linking auth provider credentials to an existing user account.

To sign out a user, call SignOut():

auth.SignOut();