DataConnectAuth.kt: Add authUid property

Author: dconeybe

firebase-dataconnect/src/main/kotlin/com/google/firebase/dataconnect/core/DataConnectAppCheck.kt

@@ -42,10 +42,10 @@ internal class DataConnectAppCheck(
   private val appCheckTokenListener = AppCheckTokenListenerImpl(logger)
 
   @DeferredApi
-  override fun addTokenListener(provider: InteropAppCheckTokenProvider) =
+  override fun registerProvider(provider: InteropAppCheckTokenProvider) =
     provider.addAppCheckTokenListener(appCheckTokenListener)
 
-  override fun removeTokenListener(provider: InteropAppCheckTokenProvider) =
+  override fun unregisterProvider(provider: InteropAppCheckTokenProvider) =
     provider.removeAppCheckTokenListener(appCheckTokenListener)
 
   override suspend fun getToken(provider: InteropAppCheckTokenProvider, forceRefresh: Boolean) =

firebase-dataconnect/src/main/kotlin/com/google/firebase/dataconnect/core/DataConnectAuth.kt

@@ -23,6 +23,8 @@ import com.google.firebase.dataconnect.core.DataConnectAuth.GetAuthTokenResult
 import com.google.firebase.dataconnect.core.Globals.toScrubbedAccessToken
 import com.google.firebase.dataconnect.core.LoggerGlobals.debug
 import com.google.firebase.internal.InternalTokenResult
+import java.util.concurrent.locks.ReentrantLock
+import kotlin.concurrent.withLock
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.tasks.await
@@ -39,14 +41,37 @@ internal class DataConnectAuth(
     blockingDispatcher = blockingDispatcher,
     logger = logger,
   ) {
-  private val idTokenListener = IdTokenListenerImpl(logger)
+
+  private data class ProviderIdTokenListenerPair(
+    val provider: InternalAuthProvider,
+    val idTokenListener: IdTokenListenerImpl,
+  )
+
+  private val providersLock = ReentrantLock()
+  private val providers = mutableListOf<ProviderIdTokenListenerPair>()
+
+  /**
+   * The Firebase Auth UID of the current user, or `null` if Firebase Auth is not (yet) available or
+   * if there is no logged-in user.
+   */
+  val authUid: String?
+    get() = providersLock.withLock { providers.lastOrNull()?.provider?.uid }
 
   @DeferredApi
-  override fun addTokenListener(provider: InternalAuthProvider) =
+  override fun registerProvider(provider: InternalAuthProvider) {
+    val idTokenListener = IdTokenListenerImpl(logger)
     provider.addIdTokenListener(idTokenListener)
+    providersLock.withLock { providers.add(ProviderIdTokenListenerPair(provider, idTokenListener)) }
+  }
 
-  override fun removeTokenListener(provider: InternalAuthProvider) =
-    provider.removeIdTokenListener(idTokenListener)
+  override fun unregisterProvider(provider: InternalAuthProvider) {
+    val idTokenListener =
+      providersLock.withLock {
+        val index = providers.indexOfLast { it.provider === provider }
+        if (index < 0) null else providers.removeAt(index).idTokenListener
+      }
+    idTokenListener?.let { provider.removeIdTokenListener(idTokenListener) }
+  }
 
   override suspend fun getToken(provider: InternalAuthProvider, forceRefresh: Boolean) =
     provider.getAccessToken(forceRefresh).await().let { GetAuthTokenResult(it.token) }

firebase-dataconnect/src/main/kotlin/com/google/firebase/dataconnect/core/DataConnectCredentialsTokenManager.kt

@@ -123,18 +123,25 @@ internal sealed class DataConnectCredentialsTokenManager<T : Any, R : GetTokenRe
   private val state = MutableStateFlow<State<T, R>>(State.New)
 
   /**
-   * Adds the token listener to the given provider.
+   * Registers the given provider [T] instance if, and when, it becomes available.
    *
-   * @see removeTokenListener
+   * The implementation may want, or need, to register a listener of some sort with the provider in
+   * order to be notified of provider state changes, such as a user logging in or logging out.
+   *
+   * @see unregisterProvider
    */
-  @DeferredApi protected abstract fun addTokenListener(provider: T)
+  @DeferredApi protected abstract fun registerProvider(provider: T)
 
   /**
-   * Removes the token listener from the given provider.
+   * Registers the given provider [T] instance, which can occur if a new provider becomes available
+   * of if [close] is called.
+   *
+   * The implementation should undo any work done by [registerProvider], such as unregistering
+   * listeners.
    *
-   * @see addTokenListener
+   * @see registerProvider
    */
-  protected abstract fun removeTokenListener(provider: T)
+  protected abstract fun unregisterProvider(provider: T)
 
   /**
    * Starts an asynchronous task to get a new access token from the given provider, forcing a token
@@ -192,7 +199,7 @@ internal sealed class DataConnectCredentialsTokenManager<T : Any, R : GetTokenRe
       is State.Initialized -> {}
       is State.Closed -> {}
       is State.StateWithProvider -> {
-        removeTokenListener(oldState.provider)
+        unregisterProvider(oldState.provider)
       }
     }
   }
@@ -398,7 +405,7 @@ internal sealed class DataConnectCredentialsTokenManager<T : Any, R : GetTokenRe
   @DeferredApi
   private fun onProviderAvailable(newProvider: T) {
     logger.debug { "onProviderAvailable(newProvider=$newProvider)" }
-    addTokenListener(newProvider)
+    registerProvider(newProvider)
 
     val oldState =
       state.getAndUpdate { currentState ->
@@ -422,7 +429,7 @@ internal sealed class DataConnectCredentialsTokenManager<T : Any, R : GetTokenRe
           "onProviderAvailable(newProvider=$newProvider)" +
             " unregistering token listener that was just added"
         }
-        removeTokenListener(newProvider)
+        unregisterProvider(newProvider)
       }
       is State.Initialized -> {}
       is State.Idle -> {}