feat: Add runtime permission check for RECORD_AUDIO

firebase-ai/firebase-ai.gradle.kts

@@ -123,6 +123,7 @@ dependencies {
   testImplementation(libs.robolectric)
   testImplementation(libs.truth)
   testImplementation(libs.mockito.core)
+  testImplementation(libs.ktor.client.mock)
 
   androidTestImplementation(libs.androidx.espresso.core)
   androidTestImplementation(libs.androidx.test.junit)

firebase-ai/src/main/kotlin/com/google/firebase/ai/LiveGenerativeModel.kt

@@ -113,7 +113,11 @@ internal constructor(
       val receivedJson = JSON.parseToJsonElement(receivedJsonStr)
 
       return if (receivedJson is JsonObject && "setupComplete" in receivedJson) {
-        LiveSession(session = webSession, blockingDispatcher = blockingDispatcher)
+        LiveSession(
+          session = webSession,
+          blockingDispatcher = blockingDispatcher,
+          firebaseApp = controller.firebaseApp
+        )
       } else {
         webSession.close()
         throw ServiceConnectionHandshakeFailedException("Unable to connect to the server")

firebase-ai/src/main/kotlin/com/google/firebase/ai/common/APIController.kt

@@ -97,7 +97,7 @@ internal constructor(
   private val requestOptions: RequestOptions,
   httpEngine: HttpClientEngine,
   private val apiClient: String,
-  private val firebaseApp: FirebaseApp,
+  internal val firebaseApp: FirebaseApp,
   private val appVersion: Int = 0,
   private val googleAppId: String,
   private val headerProvider: HeaderProvider?,

firebase-ai/src/main/kotlin/com/google/firebase/ai/type/Exceptions.kt

@@ -222,3 +222,6 @@ public class ServiceConnectionHandshakeFailedException(message: String, cause: T
 /** Catch all case for exceptions not explicitly expected. */
 public class UnknownException internal constructor(message: String, cause: Throwable? = null) :
   FirebaseAIException(message, cause)
+
+/** A required permission is missing. */
+public class PermissionMissingException(message: String) : FirebaseAIException(message)

firebase-ai/src/main/kotlin/com/google/firebase/ai/type/LiveSession.kt

@@ -17,10 +17,12 @@
 package com.google.firebase.ai.type
 
 import android.Manifest.permission.RECORD_AUDIO
+import android.content.pm.PackageManager
 import android.media.AudioFormat
 import android.media.AudioTrack
 import android.util.Log
 import androidx.annotation.RequiresPermission
+import com.google.firebase.FirebaseApp
 import com.google.firebase.ai.common.JSON
 import com.google.firebase.ai.common.util.CancelledCoroutineScope
 import com.google.firebase.ai.common.util.accumulateUntil
@@ -58,7 +60,8 @@ public class LiveSession
 internal constructor(
   private val session: ClientWebSocketSession,
   @Blocking private val blockingDispatcher: CoroutineContext,
-  private var audioHelper: AudioHelper? = null
+  private var audioHelper: AudioHelper? = null,
+  private val firebaseApp: FirebaseApp,
 ) {
   /**
    * Coroutine scope that we batch data on for [startAudioConversation].
@@ -93,12 +96,20 @@ internal constructor(
   public suspend fun startAudioConversation(
     functionCallHandler: ((FunctionCallPart) -> FunctionResponsePart)? = null
   ) {
+    val context = firebaseApp.applicationContext
+    if (
+      context.checkSelfPermission(RECORD_AUDIO) !=
+        android.content.pm.PackageManager.PERMISSION_GRANTED
+    ) {
+      throw PermissionMissingException("Missing RECORD_AUDIO permission.")
+    }
+
     FirebaseAIException.catchAsync {
       if (scope.isActive) {
         Log.w(
           TAG,
           "startAudioConversation called after the recording has already started. " +
-            "Call stopAudioConversation to close the previous connection."
+            "Call stopAudioAudioConversation to close the previous connection."
         )
         return@catchAsync
       }

firebase-ai/src/test/java/com/google/firebase/ai/type/LiveSessionTest.kt

@@ -0,0 +1,31 @@
+package com.google.firebase.ai.type
+
+import android.content.Context
+import android.content.pm.PackageManager
+import com.google.firebase.FirebaseApp
+import com.google.firebase.ai.util.doBlocking
+import io.kotest.assertions.throwables.shouldThrow
+import io.ktor.client.plugins.websocket.testing.EmptyWebSockets
+import kotlinx.coroutines.Dispatchers
+import org.junit.Test
+import org.mockito.Mockito
+
+class LiveSessionTest {
+
+  @Test
+  fun `startAudioConversation without permission throws exception`() = doBlocking {
+    val mockContext = Mockito.mock(Context::class.java)
+    Mockito.`when`(mockContext.checkSelfPermission(android.Manifest.permission.RECORD_AUDIO))
+      .thenReturn(PackageManager.PERMISSION_DENIED)
+    val mockFirebaseApp = Mockito.mock(FirebaseApp::class.java)
+    Mockito.`when`(mockFirebaseApp.applicationContext).thenReturn(mockContext)
+    val session =
+      LiveSession(
+        session = EmptyWebSockets.client.session,
+        blockingDispatcher = Dispatchers.IO,
+        firebaseApp = mockFirebaseApp
+      )
+
+    shouldThrow<PermissionMissingException> { session.startAudioConversation() }
+  }
+}