Move continuations off main thread for firebase-appcheck-debug.

Author: rosalyntan

appcheck/firebase-appcheck-debug/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(),

appcheck/firebase-appcheck-debug/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)));
   }
 }

appcheck/firebase-appcheck-debug/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();

appcheck/firebase-appcheck-debug/src/test/java/com/google/firebase/appcheck/debug/internal/DebugAppCheckProviderTest.java

@@ -103,7 +103,11 @@ public void testPublicConstructor_nullFirebaseApp_expectThrows() {
         NullPointerException.class,
         () -> {
           new DebugAppCheckProvider(
-              null, null, TestOnlyExecutors.background(), TestOnlyExecutors.blocking());
+              null,
+              null,
+              TestOnlyExecutors.lite(),
+              TestOnlyExecutors.background(),
+              TestOnlyExecutors.blocking());
         });
   }
 
@@ -137,7 +141,12 @@ 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= */ executor,
+            /* blockingExecutor= */ executor,
+            mockRetryManager);
     Task<AppCheckToken> task = provider.getToken();
 
     verify(mockNetworkClient)
@@ -155,7 +164,12 @@ 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= */ executor,
+            /* blockingExecutor= */ executor,
+            mockRetryManager);
     Task<AppCheckToken> task = provider.getToken();
 
     verify(mockNetworkClient)