Facilitates multi-platform authentication with Google Sign-In across Android, iOS, Desktop, and Web. Includes GoogleSignInButton composable for easy integration and future support plans for additional providers.
Kotlin Multiplatform Authentication library targeting Android, iOS, Desktop and Web(Kotlin/Js and Kotlin/Wasm Both). It supports following Sign In Features:
NOTE: For using Sign In With Apple or other OAuthProviders with SupabaseAuthManager, you need to setup the supabase for specific provider, refer to the supabase docs.
Youtube vide for using Google Signin In Compose Multiplatform using KotlinMultiplatformAuth How to Use Google Signin In Compose Multiplatform using KotlinMultiplatformAuth
First of all you need to initialize the KMAuthInitializer.
We need webClientId from Google Cloud Platform Console to setup the serverClientId in Google API for identifying signed-in users in backend server.
When deploying a Desktop application, ensure a smooth login experience:
googleClientRedirectHost in your code matches the port you've registered in your Google Cloud Console's Authorized redirect URIs (e.g., http://localhost:8080/callback).After initializing the KMAuthInitializer, you can use the KMAuthGoogle object to get the GoogleAuthManager Or KMAuthApple to get the AppleAuthManager Or KMAuthSupabase object to get the SupabaseAuthManager to sign in the user according to your requirement.
NOTE: For deep links setup we can follow these links for android and ios: Android: https://developer.android.com/training/app-links/deep-linking iOS: https://developer.apple.com/documentation/xcode/defining-a-custom-url-scheme-for-your-app Also make sure to add these deep link urls(with this combination -> scheme://host) in Redirect URLs in URL Configuration section of supabase auth dashboard.
You can find these sample codes in the sample
NOTE: To test the sample, Make sure to perform the Platform Setup for Android, ISO, Desktop and Web(Kotlin/Js only) as mentioned in the Platform Setup section.
If you want to use GoogleSignIn in Compose Multiplatform, you can use Either the above code
Or After setting up the KMAuthInitializer, you can use directly GoogleSignInButton composable if you
have installed the kmauth-google-compose module.
GoogleSignInButton(modifier = Modifier) { user, error ->
if (error != null) {
println("GoogleSignInButton: Error in google Sign In: $error")
}
if (user != null) {
println("GoogleSignInButton: Login Successful")
println("User Info: ${user.name}, ${user.email}, ${user.profilePicUrl}")
}
}
KMPAuth is available on Maven Central. In your root project build.gradle.kts file (or
settings.gradle file), make sure to add mavenCentral() to repositories section.
repositories {
mavenCentral()
}
Then you can add the required library module to your project as follows:
commonMain.dependencies {
api()
api()
api()
implementation()
implementation()
}
listOf(
iosArm64(),
iosSimulatorArm64()
).forEach { iosTarget ->
iosTarget.binaries.framework {
baseName =
isStatic =
export()
}
}
NOTE: For Google Sign In in iOS, You need to add Google Sign-In for iOS dependency in your xcode project.
KotlinMultiplatformAuth has the following modules:
For all other providers, we can use SupabaseAuthManager to handle sign in with other OAuth providers. And you can follow the https://supabase.com/docs/guides/auth/social-login to setup other providers in supabase auth dashboard.
NOTE: Make sure to add your android/ios deep link schemes and web redirect urls of used provider in Redirect URLs in URL Configuration section of supabase auth dashboard.
Feel free to contribute if you finds any issues or bugs or want to add a new auth provider support. Future plans are to add other providers as well such as Facebook, Github and Apple Login.
Checkout a voluntary list of projects/companies using KotlinMultiplatformAuth: https://github.com/sunildhiman90/KotlinMultiplatformAuth/discussions/3. Feel free to add your project!
// For Android platform, Its better to call it from the activity, Becoz we need activity context. We dont need to cal this from other platforms except android.
KMAuthInitializer.initContext(
kmAuthPlatformContext = KMAuthPlatformContext(this)
)
// For Sign In With Google, call initialize method from common code.
// For Desktop (JVM) platform, googleClientRedirectHost defaults to "localhost:8080".
// IMPORTANT: The port you set here must match exactly with what you have added in your Google Cloud Console "Authorized redirect URIs" (e.g., http://localhost:8080/callback).
// If you have configured a different port in the Google Console (like 56502), you must set the same here.
KMAuthInitializer.initialize(
KMAuthConfig.forGoogle(
webClientId = "YOUR_WEB_CLIENT_ID",
googleClientRedirectHost = "localhost:56502", // Optional: Defaults to "localhost:8080"
googleClientRedirectScheme = "http" // Optional: Defaults to "http"
)
)
// For Sign In With Apple or other providers, we need to call KMAuthSupabase.initialize method from common code
KMAuthSupabase.initialize(
config = KMAuthConfig.forSupabase(
supabaseUrl = "YOUR_SUPABASE_URL",
supabaseKey = "YOUR_SUPABASE_KEY",
deepLinkHost = "YOUR_DEEP_LINK_HOST",
deepLinkScheme = "YOUR_DEEP_LINK_SCHEME",
),
redirectUrl = "YOUR_REDIRECT_URL"
)
// Also if you need to provide different redirect urls, you can call KMAuthSupabase.initialize method from platform specific code for each platform.
// Also sometime if supabase does not pickup redirect urls from supabase dashboard, in that case you can provide it in initialize method.
Column(Modifier.fillMaxWidth(), horizontalAlignment = Alignment.CenterHorizontally) {
//Ideally you will be using these from ViewModel or Repo
// For Sign In With Google
val googleAuthManager = KMAuthGoogle.googleAuthManager
// For Sign In With Apple: Available only after 0.3.0
val appleAuthManager = KMAuthApple.appleAuthManager
// For Sign In With other providers such as Facebook, Github, Twitter etc. : Available only after 0.3.0
// For these providers using supabase, for setting up the supabase for specific provider, refer to the supabase docs
val supabaseAuthManager = KMAuthSupabase.getAuthManager()
val scope = rememberCoroutineScope()
Button(onClick = {
scope.launch {
val result = googleAuthManager.signIn()
if (result.isSuccess) {
println("Login Successful user: ${result.getOrNull()}")
userName = result.getOrNull()?.name
} else {
println("Error in google Sign In: ${result.exceptionOrNull()}")
}
}
}) {
Text("Sign In With Google")
}
Button(onClick = {
scope.launch {
val result = appleAuthManager.signIn()
if (result.isSuccess) {
println("Login Successful user: ${result.getOrNull()}")
userName = result.getOrNull()?.name
} else {
println("Error in apple Sign In: ${result.exceptionOrNull()}")
}
}
}) {
Text("Sign In With Apple")
}
Button(onClick = {
scope.launch {
val oauthProvider = SupabaseOAuthProvider.Github
val result = supabaseAuthManager.signInWith(supabaseOAuthProvider = oauthProvider)
if (result.isSuccess) {
println("Login Successful user: ${result.getOrNull()}")
userName = result.getOrNull()?.name
} else {
println("Error in supabase oauth provider $oauthProvider Sign In: ${result.exceptionOrNull()}")
}
}
}) {
Text("Sign In With Github")
}
}
// For all OAuthProviders except Apple, you need to call handleDeepLink from iOSApp file(ie. entry point)
// Call this method in onOpenUrl method of iOSApp file, this is not needed for sign in with apple for iOS
// becoz for iOS we are using AuthenticationServices + supabase signInWithIdToken but not signInWith oauth provider, but on Android, its needed:
ContentView()
.onOpenURL { url in
// Handle supabase deep link url
//If using kmauth-supabase
KMAuthSupabase.shared.deepLinkHandler().handleDeepLinks(url: url)
}
//Similarly for android, call this method in MainActivity, We need Android deep link handling code for Apple oauth provider as well along with other oauth providers of supabase:
override fun onNewIntent(
intent: Intent,
caller: ComponentCaller,
) {
super.onNewIntent(intent, caller)
//If using only kmauth-apple
KMAuthApple.shared.deepLinkHandler().handleDeepLinks(intent)
//If using kmauth-supabase directly
//KMAuthSupabase.shared.deepLinkHandler().handleDeepLinks(intent)
}
First of all you need to setup OAuth 2.0 in your project using any of the given methods.
First of all, you need to set up OAuth 2.0 in Google Cloud Platform Console to get the web Client ID and Client Secret.
You can follow this link to setup OAuth 2.0 in Google Cloud Platform Console.
Once you have set up OAuth 2.0, you need to get the Client ID and Client Secret from Google Cloud Platform Console and add it to your project.
You can setup OAuth 2.0 in Firebase as well. If you Enable Google as a sign-in method in the Firebase console: In the Firebase console, open the Auth section. On the Sign in method tab, enable the Google sign-in method and click Save.
Once you have enabled Google sign-in in Firebase, Firebase will automatically generate OAuth client IDs for each platform for your app and add in Google Cloud Platform Console for your firebase project. You can get the web Client ID from there from Web client from oauth clients
In this case you can skip the step of setting up OAuth 2.0 in Google Cloud Platform Console. Becoz it will be handled by Firebase.
After setting up OAuth 2.0 in Google Cloud Platform Console, you dont need any specific setup for Android except calling the KMAuthInitializer.initContext method as mentioned below.
KMAuthInitializer.initContext(
kmAuthPlatformContext = KMAuthPlatformContext(this)
)
And then setup webClientId in common code for all platforms(App composable).
KMAuthInitializer.initialize(KMAuthConfig.forGoogle(webClientId = "YOUR_WEB_CLIENT_ID"))
If you use KMAuthInitializer.initialize from common code, then you dont need to initialize the KMAuthInitializer in each platform except Android and JVM. You just need to call initContext in Android and need to call initClientSecret in desktop/jvm source set.
After setting up OAuth 2.0 in Google Cloud Platform Console, you need to call the KMAuthInitializer.init method with webClientId if you are not using Alternative Way mentioned in Android setup. If you are using Alternative Way, then you don't need to call the KMAuthInitializer.init method from iOS becoz we will call it from common code.
Additional Setup: For iOS, we need to do some additional setups as well for Google Sign-In for iOS.
<key>GIDClientID</key><string>YOUR_IOS_CLIENT_ID</string>
<key>CFBundleURLTypes</key><array>
<dict>
<key>CFBundleURLSchemes</key>
<array>
<string>YOUR_IOS_REVERSED_CLIENT_ID</string>
</array>
</dict>
</array>
Suppose your iOS client Id is :
xyzzzzz.apps.googleusercontent.com
Then your YOUR_REVERSED_CLIENT_ID value will be:
com.googleusercontent.apps.xyzzzzz
**NOTE:** You can get your YOUR_IOS_CLIENT_ID and YOUR_REVERSED_CLIENT_ID from
GoogleService-Info.plist or from Google Cloud Platform Console for iOS oauth client detail.
From ios oauth client detail, you can get your Client ID as YOUR_IOS_CLIENT_ID and iOS URL scheme as
YOUR_REVERSED_CLIENT_ID from additional information section.
ld: warning: Could not find or use auto-linked framework 'GoogleSignIn': framework 'GoogleSignIn' not foundKMAuthInitializer.initClientSecret(
clientSecret = OAUTH_CLIENT_SECRET,
)
Alternatively, you can setup clientSecret in KMAuthInitializer.initialize method itself from app composable. Then you dont need to set it here.
2. Authorized redirect URIs: You must add your loopback URI to the Google Cloud Console's Authorized redirect URIs section (e.g., http://localhost:8080/callback).
* IMPORTANT: The port you set in your KMAuthConfig (default is 8080) must match exactly with what you have added in the Google Console.
You need to call the MAuthInitializer.initialize method with webClientId if you are not using KMAuthInitializer.initialize from common code mentioned in Android setup. If you are using KMAuthInitializer.initialize from common code, then you don't need to call the KMAuthInitializer.init method from web becoz we will call it from common code.
IMP:
Also make sure you have added your allowed origin urls in : Authorized JavaScript origins section in
Google Cloud Platform Console for web auth client, Otherwise you will get this error:
Access blocked, Authorization error: The request is not allowed.
For example if you are running on localhost:8080, add this: http://localhost:8080, IN case of your production url you need to add your prod url.
IMP: First pre requisite step is to make sure You have Apple Developer Account. If you dont have it, you can get it from Apple Developer. Then you need to get membership for Apple Developer Program.: https://developer.apple.com/programs/enroll/
First of all, You need to setup Apple Sign In Provider in Supabase Auth Dashboard.
NOTE: Make sure to add your ios deep link scheme in Redirect URLs in URL Configuration section of supabase auth dashboard.
Make sure to add Sign In With Apple capability in your app in Xcode for iOS in Signing & Capabilities section.
For all DefaultOAuthProviders, You can simply use SupabaseAuthManager signInWith method.
val supabaseAuthManager = KMAuthSupabase.getAuthManager()
val result = supabaseAuthManager.signInWith(
supabaseDefaultAuthProvider = SupabaseDefaultAuthProvider.EMAIL_PASSWORD,
config = SupabaseAuthConfig().apply {
email = "test@gmail.com"
password = "123"
}
)
if (result.isSuccess) {
println("Login Successful user: ${result.getOrNull()}")
userName = result.getOrNull()?.name
} else {
println("Error in email password Sign In: ${result.exceptionOrNull()}")
}
// NOTE: IN case of web, It will redirect back to our app and reload the app after sign in from oauth provider url, then we will not be able to reflect sign in result due to reload,
// So in that case, we can collect supabaseUserResult and use this logic where we need to check sign in status.
KMAuthSupabase.supabaseUserResult.collect { result ->
Logger.d("currentSupabaseUser: $result")
if (result.isSuccess) {
_currentUser.value = result.getOrNull()?.toUser()
} else {
_currentUser.value = null
}
}
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