firebase · rosalyntan · Dec 15, 2022 · Dec 13, 2022 · Dec 13, 2022 · Dec 13, 2022
diff --git a/appcheck/firebase-appcheck-debug/CHANGELOG.md b/appcheck/firebase-appcheck-debug/CHANGELOG.md
@@ -1,6 +1,7 @@
 # Unreleased
 * [changed] Migrated [app_check] SDKs to use standard Firebase executors. (#4431, #4449)
 * [changed] Integrated the [app_check] Debug SDK with Firebase Components. (#4436)
+* [changed] Moved Task continuations off the main thread. (#4453)
 
 # 16.1.0
 * [unchanged] Updated to accommodate the release of the updated

diff --git a/...ebug/src/main/java/com/google/firebase/appcheck/debug/FirebaseAppCheckDebugRegistrar.java b/...ebug/src/main/java/com/google/firebase/appcheck/debug/FirebaseAppCheckDebugRegistrar.java
@@ -18,6 +18,7 @@
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Background;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.appcheck.debug.internal.DebugAppCheckProvider;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.ComponentRegistrar;
@@ -40,6 +41,7 @@ public class FirebaseAppCheckDebugRegistrar implements ComponentRegistrar {
 
   @Override
   public List<Component<?>> getComponents() {
+    Qualified<Executor> liteExecutor = Qualified.qualified(Lightweight.class, Executor.class);
     Qualified<Executor> backgroundExecutor = Qualified.qualified(Background.class, Executor.class);
     Qualified<Executor> blockingExecutor = Qualified.qualified(Blocking.class, Executor.class);
 
@@ -48,13 +50,15 @@ public List<Component<?>> getComponents() {
             .name(LIBRARY_NAME)
             .add(Dependency.required(FirebaseApp.class))
             .add(Dependency.optionalProvider(InternalDebugSecretProvider.class))
+            .add(Dependency.required(liteExecutor))
             .add(Dependency.required(backgroundExecutor))
             .add(Dependency.required(blockingExecutor))
             .factory(
                 (container) ->
                     new DebugAppCheckProvider(
                         container.get(FirebaseApp.class),
                         container.getProvider(InternalDebugSecretProvider.class),
+                        container.get(liteExecutor),
                         container.get(backgroundExecutor),
                         container.get(blockingExecutor)))
             .build(),

diff --git a/...ebug/src/main/java/com/google/firebase/appcheck/debug/internal/DebugAppCheckProvider.java b/...ebug/src/main/java/com/google/firebase/appcheck/debug/internal/DebugAppCheckProvider.java
@@ -16,7 +16,6 @@
 
 import static com.google.android.gms.common.internal.Preconditions.checkNotNull;
 
-import android.annotation.SuppressLint;
 import android.util.Log;
 import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
@@ -26,6 +25,7 @@
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Background;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.appcheck.AppCheckProvider;
 import com.google.firebase.appcheck.AppCheckToken;
 import com.google.firebase.appcheck.debug.InternalDebugSecretProvider;
@@ -42,17 +42,20 @@ public class DebugAppCheckProvider implements AppCheckProvider {
   private static final String UTF_8 = "UTF-8";
 
   private final NetworkClient networkClient;
+  private final Executor liteExecutor;
   private final Executor blockingExecutor;
   private final RetryManager retryManager;
   private final Task<String> debugSecretTask;
 
   public DebugAppCheckProvider(
       @NonNull FirebaseApp firebaseApp,
       @NonNull Provider<InternalDebugSecretProvider> debugSecretProvider,
+      @Lightweight Executor liteExecutor,
       @Background Executor backgroundExecutor,
       @Blocking Executor blockingExecutor) {
     checkNotNull(firebaseApp);
     this.networkClient = new NetworkClient(firebaseApp);
+    this.liteExecutor = liteExecutor;
     this.blockingExecutor = blockingExecutor;
     this.retryManager = new RetryManager();
 
@@ -70,9 +73,11 @@ public DebugAppCheckProvider(
   DebugAppCheckProvider(
       @NonNull String debugSecret,
       @NonNull NetworkClient networkClient,
+      @NonNull Executor liteExecutor,
       @NonNull Executor blockingExecutor,
       @NonNull RetryManager retryManager) {
     this.networkClient = networkClient;
+    this.liteExecutor = liteExecutor;
     this.blockingExecutor = blockingExecutor;
     this.retryManager = retryManager;
     this.debugSecretTask = Tasks.forResult(debugSecret);
@@ -102,15 +107,14 @@ static Task<String> determineDebugSecret(
     return taskCompletionSource.getTask();
   }
 
-  // TODO(b/261013814): Use an explicit executor in continuations.
-  @SuppressLint("TaskMainThread")
   @NonNull
   @Override
   public Task<AppCheckToken> getToken() {
     return debugSecretTask
-        .continueWithTask(
-            task -> {
-              ExchangeDebugTokenRequest request = new ExchangeDebugTokenRequest(task.getResult());
+        .onSuccessTask(
+            liteExecutor,
+            debugSecret -> {
+              ExchangeDebugTokenRequest request = new ExchangeDebugTokenRequest(debugSecret);
               return Tasks.call(
                   blockingExecutor,
                   () ->
@@ -119,14 +123,9 @@ public Task<AppCheckToken> getToken() {
                           NetworkClient.DEBUG,
                           retryManager));
             })
-        .continueWithTask(
-            task -> {
-              if (task.isSuccessful()) {
-                return Tasks.forResult(
-                    DefaultAppCheckToken.constructFromAppCheckTokenResponse(task.getResult()));
-              }
-              // TODO: Surface more error details.
-              return Tasks.forException(task.getException());
-            });
+        .onSuccessTask(
+            liteExecutor,
+            response ->
+                Tasks.forResult(DefaultAppCheckToken.constructFromAppCheckTokenResponse(response)));
   }
 }
diff --git a/.../src/test/java/com/google/firebase/appcheck/debug/FirebaseAppCheckDebugRegistrarTest.java b/.../src/test/java/com/google/firebase/appcheck/debug/FirebaseAppCheckDebugRegistrarTest.java
@@ -19,6 +19,7 @@
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Background;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.Dependency;
 import com.google.firebase.components.Qualified;
@@ -42,6 +43,7 @@ public void testGetComponents() {
         .containsExactly(
             Dependency.required(FirebaseApp.class),
             Dependency.optionalProvider(InternalDebugSecretProvider.class),
+            Dependency.required(Qualified.qualified(Lightweight.class, Executor.class)),
             Dependency.required(Qualified.qualified(Background.class, Executor.class)),
             Dependency.required(Qualified.qualified(Blocking.class, Executor.class)));
     assertThat(appCheckDebugComponent.isLazy()).isTrue();

diff --git a/.../src/test/java/com/google/firebase/appcheck/debug/internal/DebugAppCheckProviderTest.java b/.../src/test/java/com/google/firebase/appcheck/debug/internal/DebugAppCheckProviderTest.java
@@ -74,7 +74,9 @@ public class DebugAppCheckProviderTest {
   private StorageHelper storageHelper;
   private SharedPreferences sharedPreferences;
   // TODO(b/258273630): Use TestOnlyExecutors instead of MoreExecutors.directExecutor().
-  private Executor executor = MoreExecutors.directExecutor();
+  private Executor liteExecutor = MoreExecutors.directExecutor();
+  private Executor backgroundExecutor = MoreExecutors.directExecutor();
+  private Executor blockingExecutor = MoreExecutors.directExecutor();
 
   @Before
   public void setup() {
@@ -103,7 +105,11 @@ public void testPublicConstructor_nullFirebaseApp_expectThrows() {
         NullPointerException.class,
         () -> {
           new DebugAppCheckProvider(
-              null, null, TestOnlyExecutors.background(), TestOnlyExecutors.blocking());
+              null,
+              null,
+              TestOnlyExecutors.lite(),
+              TestOnlyExecutors.background(),
+              TestOnlyExecutors.blocking());
         });
   }
 
@@ -113,7 +119,7 @@ public void testDetermineDebugSecret_noStoredSecret_createsNewSecret() {
     assertThat(storageHelper.retrieveDebugSecret()).isNull();
 
     Task<String> debugSecretTask =
-        DebugAppCheckProvider.determineDebugSecret(mockFirebaseApp, executor);
+        DebugAppCheckProvider.determineDebugSecret(mockFirebaseApp, backgroundExecutor);
     assertThat(storageHelper.retrieveDebugSecret()).isNotNull();
     assertThat(storageHelper.retrieveDebugSecret()).isEqualTo(debugSecretTask.getResult());
   }
@@ -123,7 +129,7 @@ public void testDetermineDebugSecret_storedSecret_usesExistingSecret() {
     storageHelper.saveDebugSecret(DEBUG_SECRET);
 
     Task<String> debugSecretTask =
-        DebugAppCheckProvider.determineDebugSecret(mockFirebaseApp, executor);
+        DebugAppCheckProvider.determineDebugSecret(mockFirebaseApp, backgroundExecutor);
     assertThat(debugSecretTask.getResult()).isEqualTo(DEBUG_SECRET);
     assertThat(storageHelper.retrieveDebugSecret()).isEqualTo(DEBUG_SECRET);
   }
@@ -137,7 +143,8 @@ public void exchangeDebugToken_onSuccess_setsTaskResult() throws Exception {
     when(mockAppCheckTokenResponse.getTimeToLive()).thenReturn(TIME_TO_LIVE);
 
     DebugAppCheckProvider provider =
-        new DebugAppCheckProvider(DEBUG_SECRET, mockNetworkClient, executor, mockRetryManager);
+        new DebugAppCheckProvider(
+            DEBUG_SECRET, mockNetworkClient, liteExecutor, blockingExecutor, mockRetryManager);
     Task<AppCheckToken> task = provider.getToken();
 
     verify(mockNetworkClient)
@@ -155,7 +162,8 @@ public void exchangeDebugToken_onFailure_setsTaskException() throws Exception {
         .thenThrow(new IOException());
 
     DebugAppCheckProvider provider =
-        new DebugAppCheckProvider(DEBUG_SECRET, mockNetworkClient, executor, mockRetryManager);
+        new DebugAppCheckProvider(
+            DEBUG_SECRET, mockNetworkClient, liteExecutor, blockingExecutor, mockRetryManager);
     Task<AppCheckToken> task = provider.getToken();
 
     verify(mockNetworkClient)

diff --git a/appcheck/firebase-appcheck-playintegrity/CHANGELOG.md b/appcheck/firebase-appcheck-playintegrity/CHANGELOG.md
@@ -1,6 +1,7 @@
 # Unreleased
 * [changed] Migrated [app_check] SDKs to use standard Firebase executors. (#4431, #4449)
 * [changed] Integrated the [app_check] Play Integrity SDK with Firebase Components. (#4436)
+* [changed] Moved Task continuations off the main thread. (#4453)
 
 # 16.1.0
 * [unchanged] Updated to accommodate the release of the updated

diff --git a/...va/com/google/firebase/appcheck/playintegrity/FirebaseAppCheckPlayIntegrityRegistrar.java b/...va/com/google/firebase/appcheck/playintegrity/FirebaseAppCheckPlayIntegrityRegistrar.java
@@ -17,6 +17,7 @@
 import com.google.android.gms.common.annotation.KeepForSdk;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.appcheck.playintegrity.internal.PlayIntegrityAppCheckProvider;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.ComponentRegistrar;
@@ -39,17 +40,21 @@ public class FirebaseAppCheckPlayIntegrityRegistrar implements ComponentRegistra
 
   @Override
   public List<Component<?>> getComponents() {
+    Qualified<Executor> liteExecutor = Qualified.qualified(Lightweight.class, Executor.class);
     Qualified<Executor> blockingExecutor = Qualified.qualified(Blocking.class, Executor.class);
 
     return Arrays.asList(
         Component.builder(PlayIntegrityAppCheckProvider.class)
             .name(LIBRARY_NAME)
             .add(Dependency.required(FirebaseApp.class))
+            .add(Dependency.required(liteExecutor))
             .add(Dependency.required(blockingExecutor))
             .factory(
                 (container) ->
                     new PlayIntegrityAppCheckProvider(
-                        container.get(FirebaseApp.class), container.get(blockingExecutor)))
+                        container.get(FirebaseApp.class),
+                        container.get(liteExecutor),
+                        container.get(blockingExecutor)))
             .build(),
         LibraryVersionComponent.create(LIBRARY_NAME, BuildConfig.VERSION_NAME));
   }

diff --git a/...va/com/google/firebase/appcheck/playintegrity/internal/PlayIntegrityAppCheckProvider.java b/...va/com/google/firebase/appcheck/playintegrity/internal/PlayIntegrityAppCheckProvider.java
@@ -14,7 +14,6 @@
 
 package com.google.firebase.appcheck.playintegrity.internal;
 
-import android.annotation.SuppressLint;
 import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
 import com.google.android.gms.tasks.Task;
@@ -25,6 +24,7 @@
 import com.google.android.play.core.integrity.IntegrityTokenResponse;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.appcheck.AppCheckProvider;
 import com.google.firebase.appcheck.AppCheckToken;
 import com.google.firebase.appcheck.internal.DefaultAppCheckToken;
@@ -39,15 +39,19 @@ public class PlayIntegrityAppCheckProvider implements AppCheckProvider {
   private final String projectNumber;
   private final IntegrityManager integrityManager;
   private final NetworkClient networkClient;
+  private final Executor liteExecutor;
   private final Executor blockingExecutor;
   private final RetryManager retryManager;
 
   public PlayIntegrityAppCheckProvider(
-      @NonNull FirebaseApp firebaseApp, @Blocking Executor blockingExecutor) {
+      @NonNull FirebaseApp firebaseApp,
+      @Lightweight Executor liteExecutor,
+      @Blocking Executor blockingExecutor) {
     this(
         firebaseApp.getOptions().getGcmSenderId(),
         IntegrityManagerFactory.create(firebaseApp.getApplicationContext()),
         new NetworkClient(firebaseApp),
+        liteExecutor,
         blockingExecutor,
         new RetryManager());
   }
@@ -57,22 +61,23 @@ public PlayIntegrityAppCheckProvider(
       @NonNull String projectNumber,
       @NonNull IntegrityManager integrityManager,
       @NonNull NetworkClient networkClient,
+      @NonNull Executor liteExecutor,
       @NonNull Executor blockingExecutor,
       @NonNull RetryManager retryManager) {
     this.projectNumber = projectNumber;
     this.integrityManager = integrityManager;
     this.networkClient = networkClient;
+    this.liteExecutor = liteExecutor;
     this.blockingExecutor = blockingExecutor;
     this.retryManager = retryManager;
   }
 
-  // TODO(b/261013814): Use an explicit executor in continuations.
-  @SuppressLint("TaskMainThread")
   @NonNull
   @Override
   public Task<AppCheckToken> getToken() {
     return getPlayIntegrityAttestation()
         .onSuccessTask(
+            liteExecutor,
             integrityTokenResponse -> {
               ExchangePlayIntegrityTokenRequest request =
                   new ExchangePlayIntegrityTokenRequest(integrityTokenResponse.token());
@@ -85,32 +90,30 @@ public Task<AppCheckToken> getToken() {
                           retryManager));
             })
         .onSuccessTask(
-            appCheckTokenResponse -> {
-              return Tasks.forResult(
-                  DefaultAppCheckToken.constructFromAppCheckTokenResponse(appCheckTokenResponse));
-            });
+            liteExecutor,
+            appCheckTokenResponse ->
+                Tasks.forResult(
+                    DefaultAppCheckToken.constructFromAppCheckTokenResponse(
+                        appCheckTokenResponse)));
   }
 
-  // TODO(b/261013814): Use an explicit executor in continuations.
-  @SuppressLint("TaskMainThread")
   @NonNull
   private Task<IntegrityTokenResponse> getPlayIntegrityAttestation() {
     GeneratePlayIntegrityChallengeRequest generateChallengeRequest =
         new GeneratePlayIntegrityChallengeRequest();
-    Task<GeneratePlayIntegrityChallengeResponse> generateChallengeTask =
-        Tasks.call(
+    return Tasks.call(
             blockingExecutor,
             () ->
                 GeneratePlayIntegrityChallengeResponse.fromJsonString(
                     networkClient.generatePlayIntegrityChallenge(
-                        generateChallengeRequest.toJsonString().getBytes(UTF_8), retryManager)));
-    return generateChallengeTask.onSuccessTask(
-        generatePlayIntegrityChallengeResponse -> {
-          return integrityManager.requestIntegrityToken(
-              IntegrityTokenRequest.builder()
-                  .setCloudProjectNumber(Long.parseLong(projectNumber))
-                  .setNonce(generatePlayIntegrityChallengeResponse.getChallenge())
-                  .build());
-        });
+                        generateChallengeRequest.toJsonString().getBytes(UTF_8), retryManager)))
+        .onSuccessTask(
+            liteExecutor,
+            generatePlayIntegrityChallengeResponse ->
+                integrityManager.requestIntegrityToken(
+                    IntegrityTokenRequest.builder()
+                        .setCloudProjectNumber(Long.parseLong(projectNumber))
+                        .setNonce(generatePlayIntegrityChallengeResponse.getChallenge())
+                        .build()));
   }
 }
diff --git a/...om/google/firebase/appcheck/playintegrity/FirebaseAppCheckPlayIntegrityRegistrarTest.java b/...om/google/firebase/appcheck/playintegrity/FirebaseAppCheckPlayIntegrityRegistrarTest.java
@@ -18,6 +18,7 @@
 
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.annotations.concurrent.Blocking;
+import com.google.firebase.annotations.concurrent.Lightweight;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.Dependency;
 import com.google.firebase.components.Qualified;
@@ -40,6 +41,7 @@ public void testGetComponents() {
     assertThat(appCheckPlayIntegrityComponent.getDependencies())
         .containsExactly(
             Dependency.required(FirebaseApp.class),
+            Dependency.required(Qualified.qualified(Lightweight.class, Executor.class)),
             Dependency.required(Qualified.qualified(Blocking.class, Executor.class)));
     assertThat(appCheckPlayIntegrityComponent.isLazy()).isTrue();
   }