Forked to upgrade base library to newer version

https://developer.android.com/identity/sign-in/legacy-gsi-migration https://developers.google.com/identity/sign-in/ios/quick-migration-guide

Thank for ios fix which was cherrypicked from this fork : https://github.com/pillsgood/google-signin-unity which came from @DulgiKim googlesamples#205 (comment)

Android was migrated to use CredentialManager and AuthorizationClient since GoogleSignInAccount was deprecated

However, GoogleIdTokenCredential actually not provide numeric unique ID anymore and set email as userId instead, so I have to extract jwt sub value from idToken (which seem like the same id as userId from GoogleSignIn of other platform)

Also, this new system seem like it did not support email hint. And now require WebClientId in addition to Android Client ID. Which need to provided at configuration initialization

        GoogleSignIn.Configuration = new GoogleSignInConfiguration() {
            RequestEmail = true,
            RequestProfile = true,
            RequestIdToken = true,
            RequestAuthCode = true,
            // must be web client ID, not android client ID
            WebClientId = "XXXXXXXXX-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.apps.googleusercontent.com",
#if UNITY_EDITOR || UNITY_STANDALONE
            ClientSecret = "XXXXXX-xxxXXXxxxXXXxxx-xxxxXXXXX" // optional for windows/macos and test in editor
#endif
        };

Tested in unity 2021.3.21 and unity 6000.0.5

Add UPM dependency with branch tag https://github.com/Thaina/google-signin-unity.git#newmigration

{
  "dependencies": {
    "com.google.external-dependency-manager": "https://github.com/googlesamples/unity-jar-resolver.git?path=upm",
    "com.google.signin": "https://github.com/Thaina/google-signin-unity.git#newmigration",
    ...
  }
}

Also, New version of iOS recommend that we should set GIDClientID and GIDServerClientID into Info.plist

So I have add an editor tool PListProcessor that look for plist files in the project, extract CLIENT_ID and WEB_CLIENT_ID property of the plist which contain the BUNDLE_ID with the same name as bundle identifier of the project

The plist file in the project should be downloaded from Google Cloud Console credential page

Select iOS credential and download at ⬇ button

<!-- This plist was the default format downloaded from your google cloud console -->
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>CLIENT_ID</key> 
	<string>{YourCloudProjectID}-yyyyyYYYYyyyyYYYYYYYYYYYYYYyyyyyy.apps.googleusercontent.com</string>
	<key>REVERSED_CLIENT_ID</key>
	<string>com.googleusercontent.apps.{YourCloudProjectID}-yyyyyYYYYyyyyYYYYYYYYYYYYYYyyyyyy</string>
	<key>PLIST_VERSION</key>
	<string>1</string>
	<key>BUNDLE_ID</key>
	<string>com.{YourCompany}.{YourProductName}</string>
<!-- Optional, These 2 lines below should be added manually if you need ServerAuthCode -->
  <key>WEB_CLIENT_ID</key>
  <string>{YourCloudProjectID}-zzzZZZZZZZZZZZZZZzzzzzzzzzzZZZzzz.apps.googleusercontent.com</string>
</dict>
</plist>

Document below is original README, some information might be outdated

Google Sign-In Unity Plugin

Copyright (c) 2017 Google Inc. All rights reserved.

Overview

Google Sign-In API plugin for Unity game engine. Works with Android and iOS. This plugin exposes the Google Sign-In API within Unity. This is specifically intended to be used by Unity projects that require OAuth ID tokens or server auth codes.

It is cross-platform, supporting both Android and iOS.

See Google Sign-In for Android for more information.

Configuring the application on the API Console

To authenticate you need to create credentials on the API console for your application. The steps to do this are available on Google Sign-In for Android or as part of Firebase configuration. In order to access ID tokens or server auth codes, you also need to configure a web client ID.

How to build the sample

Get a Google Sign-In configuration file

This file contains the client-side information needed to use Google Sign-in. The details on how to do this are documented on the Developer website.

Once you have the configuration file, open it in a text editor. In the middle of the file you should see the oauth_client section:

      "oauth_client": [
        {
          "client_id": "411000067631-hmh4e210xxxxxxxxxx373t3icpju8ooi.apps.googleusercontent.com",
          "client_type": 3
        },
        {
          "client_id": "411000067631-udra361txxxxxxxxxx561o9u9hc0java.apps.googleusercontent.com",
          "client_type": 1,
          "android_info": {
            "package_name": "com.your.package.name.",
            "certificate_hash": "7ada045cccccccccc677a38c91474628d6c55d03"
          }
        }
      ]

There are 3 values you need for configuring your Unity project:

1. The Web client ID. This is needed for generating a server auth code for your backend server, or for generating an ID token. This is the client_id value for the oauth client with client_type == 3.
2. The package_name. The client entry with client_type == 1 is the Android client. The package_name must be entered in the Unity player settings.
3. The keystore used to sign your application. This is configured in the publishing settings of the Android Player properties in the Unity editor. This must be the same keystore used to generate the SHA1 fingerprint when creating the application on the console. NOTE: The configutation file does not reference the keystore, you need to keep track of this yourself.

Create a new project and import the plugin

Create a new Unity project and import the GoogleSignIn-1.0.0.unitypackage (or the latest version). This contains native code, C# Unity code needed to call the Google Sign-In API for both Android and iOS.

Import the sample scene

Import the GoogleSignIn-sample.unitypackage which contains the sample scene and scripts. This package is not needed if you are integrating Google Sign-in into your own application.

Configure the web client id

1. Open the sample scene in Assets/SignInSample/MainScene.
2. Select the Canvas object in the hierarchy and enter the web client id in the SignInSampleScript component.

Building for Android

1. Under Build Settings, select Android as the target platform.
2. Set the package name in the player settings to the package_name you found in the configuration file.
3. Select the keystore file, the key alias, and passwords.
4. Resolve the Google Play Services SDK dependencies by selecting from the menu: Assets/Play Services Resolver/Android Resolver/Resolve. This will add the required .aar files to your project in Assets/Plugins/Android.

Building for iOS

For iOS, follow the instructions for creating a GoogleService-Info.plist file on https://developers.google.com/identity/sign-in/ios/start-integrating.

In Unity, after switching to the iOS player, make sure to run the Play Services Resolver. This will add the required frameworks and libraries to the XCode project via CocoPods.

After generating the XCode project from Unity, download the GoogleService-Info.plist file from the Google Developers website and add it to your XCode project.

Using the Games Profile to sign in on Android

To use the Play Games Services Gamer profile when signing in, you need to edit the dependencies in Assets/GoogleSignIn/Editor/GoogleSignInDependencies.xml.

Uncomment the play-services-games dependency and re-run the resolution.

Using this plugin with Firebase Auth

Follow the instructions to use Firebase Auth with Credentials on the Firebase developer website.

Make sure to copy the google-services.json and/or GoogleService-Info.plist to your Unity project.

Then to use Google SignIn with Firebase Auth, you need to request an ID token when authenticating. The steps are:

1. Configure Google SignIn to request an id token and set the web client id as described above.
2. Call SignIn() (or SignInSilently()).
3. When handling the response, use the ID token to create a Firebase Credential.
4. Call Firebase Auth method SignInWithCredential().

    GoogleSignIn.Configuration = new GoogleSignInConfiguration {
      RequestIdToken = true,
      // Copy this value from the google-service.json file.
      // oauth_client with type == 3
      WebClientId = "1072123000000-iacvb7489h55760s3o2nf1xxxxxxxx.apps.googleusercontent.com"
    };

    Task<GoogleSignInUser> signIn = GoogleSignIn.DefaultInstance.SignIn ();

    TaskCompletionSource<FirebaseUser> signInCompleted = new TaskCompletionSource<FirebaseUser> ();
    signIn.ContinueWith (task => {
      if (task.IsCanceled) {
        signInCompleted.SetCanceled ();
      } else if (task.IsFaulted) {
        signInCompleted.SetException (task.Exception);
      } else {

        Credential credential = Firebase.Auth.GoogleAuthProvider.GetCredential (((Task<GoogleSignInUser>)task).Result.IdToken, null);
        auth.SignInWithCredentialAsync (credential).ContinueWith (authTask => {
          if (authTask.IsCanceled) {
            signInCompleted.SetCanceled();
          } else if (authTask.IsFaulted) {
            signInCompleted.SetException(authTask.Exception);
          } else {
            signInCompleted.SetResult(((Task<FirebaseUser>)authTask).Result);
          }
        });
      }
    });

Building the Plugin

To build the plugin run ./gradlew -PlintAbortOnError build_all. This builds the support aar library with lint warnings as errors and packages the plugin into a .unitypackage file. It also packages the sample scene and script in a separate package.

There's also a shortcut for linux/mac: ./build_all.

Questions? Problems?

Post questions to this Github project.