Users can sign in with Github OAuth on Android

app/build.gradle.kts

@@ -55,6 +55,7 @@ dependencies {
   implementation(libs.material)
   implementation(libs.androidx.activity)
   implementation(libs.androidx.constraintlayout)
+  implementation(libs.androidx.browser)
   implementation(platform(libs.androidx.compose.bom))
   implementation(libs.androidx.material3)
 

app/src/main/AndroidManifest.xml

@@ -20,12 +20,22 @@
         <activity
             android:name=".MainActivity"
             android:exported="true"
+            android:launchMode="singleTask"
             android:configChanges="orientation|screenSize|screenLayout|smallestScreenSize">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
+
+            <intent-filter>
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data
+                    android:scheme="rubyevents"
+                    android:host="auth" />
+            </intent-filter>
         </activity>
     </application>
 </manifest>

app/src/main/java/org/rubyevents/app/MainActivity.kt

@@ -1,5 +1,6 @@
 package org.rubyevents.app
 
+import android.content.Intent
 import android.os.Bundle
 import android.view.View
 import androidx.activity.enableEdgeToEdge
@@ -9,6 +10,7 @@ import dev.hotwire.navigation.activities.HotwireActivity
 import dev.hotwire.navigation.tabs.HotwireBottomNavigationController
 import dev.hotwire.navigation.util.applyDefaultImeWindowInsets
 import dev.hotwire.navigation.tabs.navigatorConfigurations
+import org.rubyevents.app.hotwire.bridge.OAuthComponent
 import org.rubyevents.app.hotwire.tabs
 import org.rubyevents.app.hotwire.viewmodels.MainActivityViewModel
 
@@ -22,6 +24,20 @@ class MainActivity : HotwireActivity() {
     setContentView(R.layout.activity_main)
     findViewById<View>(R.id.root).applyDefaultImeWindowInsets()
     initializeBottomTabs()
+    handleOAuthRedirect(intent)
+  }
+
+  override fun onNewIntent(intent: Intent) {
+    super.onNewIntent(intent)
+    setIntent(intent)
+    handleOAuthRedirect(intent)
+  }
+
+  private fun handleOAuthRedirect(intent: Intent?) {
+    if (intent?.action != Intent.ACTION_VIEW) return
+    val uri = intent.data ?: return
+    if (uri.scheme != "rubyevents" || uri.host != "auth") return
+    OAuthComponent.handleRedirect(uri)
   }
 
   private fun initializeBottomTabs() {

app/src/main/java/org/rubyevents/app/MainApplication.kt

@@ -12,6 +12,8 @@ import dev.hotwire.navigation.config.registerBridgeComponents
 import dev.hotwire.navigation.config.registerFragmentDestinations
 import dev.hotwire.navigation.fragments.HotwireWebBottomSheetFragment
 import org.rubyevents.app.hotwire.bridge.ButtonComponent
+import org.rubyevents.app.hotwire.bridge.OAuthComponent
+import org.rubyevents.app.hotwire.fragments.RefreshAppFragment
 import org.rubyevents.app.hotwire.fragments.WebFragment
 import org.rubyevents.app.hotwire.CustomWebView
 
@@ -32,6 +34,7 @@ class MainApplication : Application() {
         Hotwire.registerFragmentDestinations(
             WebFragment::class,
             HotwireWebBottomSheetFragment::class,
+            RefreshAppFragment::class,
         )
 
         // PathConfiguration
@@ -44,7 +47,8 @@ class MainApplication : Application() {
 
         // Bridge components
         Hotwire.registerBridgeComponents(
-            BridgeComponentFactory("button", ::ButtonComponent)
+            BridgeComponentFactory("button", ::ButtonComponent),
+            BridgeComponentFactory("oauth", ::OAuthComponent)
         )
 
         // Custom WebView

app/src/main/java/org/rubyevents/app/Router.kt

@@ -28,4 +28,7 @@ object Router {
 
     val speakersURL: String
         get() { return "$baseURL/speakers" }
+
+    val signInURL: String
+        get() { return "$baseURL/hotwire/native/v1/oauth" }
 }

app/src/main/java/org/rubyevents/app/hotwire/Tabs.kt

@@ -45,9 +45,20 @@ private val speakers = HotwireBottomTab(
     )
 )
 
+private val signIn = HotwireBottomTab(
+    title = "Sign In",
+    iconResId = R.drawable.ic_tab_profile,
+    configuration = NavigatorConfiguration(
+        name = "sign_in",
+        navigatorHostId = R.id.settings_navigator_host,
+        startLocation = Router.signInURL
+    )
+)
+
 val tabs = listOf(
     home,
     events,
     talks,
-    speakers
+    speakers,
+    signIn
 )

app/src/main/java/org/rubyevents/app/hotwire/bridge/OAuthComponent.kt

@@ -0,0 +1,111 @@
+package org.rubyevents.app.hotwire.bridge
+
+import android.net.Uri
+import android.util.Log
+import androidx.browser.customtabs.CustomTabColorSchemeParams
+import androidx.browser.customtabs.CustomTabsIntent
+import androidx.core.content.ContextCompat
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.lifecycleScope
+import androidx.lifecycle.repeatOnLifecycle
+import dev.hotwire.core.bridge.BridgeComponent
+import dev.hotwire.core.bridge.BridgeDelegate
+import dev.hotwire.core.bridge.Message
+import dev.hotwire.navigation.destinations.HotwireDestination
+import dev.hotwire.navigation.fragments.HotwireFragment
+import kotlinx.coroutines.channels.BufferOverflow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.launch
+import kotlinx.serialization.Serializable
+import org.rubyevents.app.R
+import org.rubyevents.app.Router
+
+class OAuthComponent(
+    name: String,
+    private val bridgeDelegate: BridgeDelegate<HotwireDestination>
+) : BridgeComponent<HotwireDestination>(name, bridgeDelegate) {
+
+    private val fragment: HotwireFragment
+        get() = bridgeDelegate.destination.fragment as HotwireFragment
+
+    private var pendingSignIn: Message? = null
+
+    override fun onReceive(message: Message) {
+        Log.d(TAG, "onReceive event=${message.event} jsonData=${message.jsonData}")
+        when (message.event) {
+            "signIn" -> handleSignIn(message)
+            "disconnect" -> { pendingSignIn = null }
+            else -> Log.w(TAG, "Unknown event: ${message.event}")
+        }
+    }
+
+    override fun onStart() {
+        fragment.viewLifecycleOwner.lifecycleScope.launch {
+            fragment.viewLifecycleOwner.repeatOnLifecycle(Lifecycle.State.STARTED) {
+                callbacks.collect { onRedirect(it) }
+            }
+        }
+    }
+
+    private fun handleSignIn(message: Message) {
+        val path = message.data<MessageData>()?.startPath ?: return
+        val url = resolveAgainstBaseUrl(path)
+        Log.d(TAG, "handleSignIn url=$url")
+        pendingSignIn = message
+        clearCallbacks()
+        launchCustomTab(url)
+    }
+
+    private fun resolveAgainstBaseUrl(path: String): String {
+        return Router.startURL.trimEnd('/') + (if (path.startsWith("/")) path else "/$path")
+    }
+
+    private fun launchCustomTab(url: String) {
+        val context = fragment.requireContext()
+        val brandColor = ContextCompat.getColor(context, R.color.main_app_color)
+        CustomTabsIntent.Builder()
+            .setDefaultColorSchemeParams(
+                CustomTabColorSchemeParams.Builder()
+                    .setToolbarColor(brandColor)
+                    .build()
+            )
+            .setShowTitle(true)
+            .build()
+            .launchUrl(context, Uri.parse(url))
+    }
+
+    private fun onRedirect(uri: Uri) {
+        val message = pendingSignIn ?: return
+        pendingSignIn = null
+        clearCallbacks()
+        val token = uri.getQueryParameter("token")
+        replyWith(message.replacing(event = "success", data = SuccessData(token = token)))
+        Log.d(TAG, "Replied success for $uri (originalEvent=${message.event})")
+    }
+
+    @Serializable
+    data class MessageData(val startPath: String? = null)
+
+    @Serializable
+    data class SuccessData(val token: String? = null)
+
+    companion object {
+        private const val TAG = "OAuthComponent"
+
+        private val callbacksFlow = MutableSharedFlow<Uri>(
+            replay = 1,
+            extraBufferCapacity = 1,
+            onBufferOverflow = BufferOverflow.DROP_OLDEST
+        )
+        private val callbacks: SharedFlow<Uri> = callbacksFlow
+
+        fun handleRedirect(uri: Uri) {
+            callbacksFlow.tryEmit(uri)
+        }
+
+        private fun clearCallbacks() {
+            callbacksFlow.resetReplayCache()
+        }
+    }
+}

app/src/main/java/org/rubyevents/app/hotwire/fragments/RefreshAppFragment.kt

@@ -0,0 +1,16 @@
+package org.rubyevents.app.hotwire.fragments
+
+import android.os.Bundle
+import dev.hotwire.navigation.destinations.HotwireDestinationDeepLink
+import dev.hotwire.navigation.fragments.HotwireFragment
+import org.rubyevents.app.MainActivity
+
+@HotwireDestinationDeepLink(uri = "hotwire://fragment/refresh_app")
+class RefreshAppFragment : HotwireFragment() {
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+
+        navigator.reset()
+        (activity as? MainActivity)?.delegate?.resetNavigators()
+    }
+}

app/src/main/res/drawable/ic_tab_profile.xml

@@ -0,0 +1,13 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android" xmlns:aapt="http://schemas.android.com/aapt"
+    android:viewportWidth="960"
+    android:viewportHeight="960"
+    android:width="24dp"
+    android:height="24dp">
+    <group
+        android:translateX="-0"
+        android:translateY="960">
+        <path
+            android:pathData="M480 -480q-66 0 -113 -47t-47 -113q0 -66 47 -113t113 -47q66 0 113 47t47 113q0 66 -47 113t-113 47ZM160 -160v-112q0 -34 17.5 -62.5T224 -378q62 -31 126 -46.5T480 -440q66 0 130 15.5T736 -378q29 14 46.5 42.5T800 -272v112H160Zm80 -80h480v-32q0 -11 -5.5 -20T700 -306q-54 -27 -109 -40.5T480 -360q-56 0 -111 13.5T260 -306q-9 5 -14.5 14t-5.5 20v32Zm240 -320q33 0 56.5 -23.5T560 -640q0 -33 -23.5 -56.5T480 -720q-33 0 -56.5 23.5T400 -640q0 33 23.5 56.5T480 -560Zm0 -80Zm0 400Z"
+            android:fillColor="#E3E3E3" />
+    </group>
+</vector>

app/src/main/res/layout/activity_main.xml

@@ -44,6 +44,15 @@
         app:layout_constraintBottom_toTopOf="@id/bottom_nav"
         app:defaultNavHost="false" />
 
+    <androidx.fragment.app.FragmentContainerView
+        android:id="@+id/settings_navigator_host"
+        android:name="dev.hotwire.navigation.navigator.NavigatorHost"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        app:layout_constraintTop_toTopOf="parent"
+        app:layout_constraintBottom_toTopOf="@id/bottom_nav"
+        app:defaultNavHost="false" />
+
     <com.google.android.material.bottomnavigation.BottomNavigationView
         android:id="@+id/bottom_nav"
         android:layout_width="match_parent"

gradle/libs.versions.toml

@@ -14,6 +14,7 @@ navigationFragments = "1.2.0"
 kotlinxSerializationJson = "1.8.1"
 composeBom = "2025.03.00"
 material3 = "1.3.2"
+browser = "1.8.0"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -29,6 +30,7 @@ navigation-fragments = { group = "dev.hotwire", name = "navigation-fragments", v
 kotlinx-serialization-json = { group = "org.jetbrains.kotlinx", name = "kotlinx-serialization-json", version.ref = "kotlinxSerializationJson" }
 androidx-compose-bom = { group = "androidx.compose", name = "compose-bom", version.ref = "composeBom" }
 androidx-material3 = { group = "androidx.compose.material3", name = "material3", version.ref = "material3" }
+androidx-browser = { group = "androidx.browser", name = "browser", version.ref = "browser" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }