update mlkitdownloader to use executors

firebase-ml-modeldownloader/firebase-ml-modeldownloader.gradle

@@ -64,6 +64,7 @@ dependencies {
     implementation project(':encoders:firebase-encoders-json')
     implementation project(':firebase-common')
     implementation project(':firebase-components')
+    implementation project(':firebase-annotations')
     implementation project(':firebase-datatransport')
     implementation project(':firebase-installations-interop')
     implementation project(':transport:transport-api')

firebase-ml-modeldownloader/src/main/java/com/google/firebase/ml/modeldownloader/FirebaseModelDownloader.java

@@ -13,7 +13,6 @@
 // limitations under the License.
 package com.google.firebase.ml.modeldownloader;
 
-import android.annotation.SuppressLint;
 import android.os.Build.VERSION_CODES;
 import android.util.Log;
 import androidx.annotation.NonNull;
@@ -26,6 +25,8 @@
 import com.google.android.gms.tasks.Tasks;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseOptions;
+import com.google.firebase.annotations.concurrent.Background;
+import com.google.firebase.annotations.concurrent.Blocking;
 import com.google.firebase.ml.modeldownloader.internal.CustomModelDownloadService;
 import com.google.firebase.ml.modeldownloader.internal.FirebaseMlLogEvent.ModelDownloadLogEvent.DownloadStatus;
 import com.google.firebase.ml.modeldownloader.internal.FirebaseMlLogEvent.ModelDownloadLogEvent.ErrorCode;
@@ -36,7 +37,6 @@
 import java.io.File;
 import java.util.Set;
 import java.util.concurrent.Executor;
-import java.util.concurrent.Executors;
 import javax.inject.Inject;
 
 public class FirebaseModelDownloader {
@@ -47,51 +47,33 @@ public class FirebaseModelDownloader {
   private final ModelFileDownloadService fileDownloadService;
   private final ModelFileManager fileManager;
   private final CustomModelDownloadService modelDownloadService;
-  private final Executor executor;
+  private final Executor bgExecutor;
+  private final Executor blockingExecutor;
 
   private final FirebaseMlLogger eventLogger;
   private final CustomModel.Factory modelFactory;
 
   @Inject
-  @RequiresApi(api = VERSION_CODES.KITKAT)
-  // TODO(b/258424267): Migrate to go/firebase-android-executors
-  @SuppressLint("ThreadPoolCreation")
-  FirebaseModelDownloader(
-      FirebaseOptions firebaseOptions,
-      SharedPreferencesUtil sharedPreferencesUtil,
-      ModelFileDownloadService fileDownloadService,
-      CustomModelDownloadService modelDownloadService,
-      ModelFileManager fileManager,
-      FirebaseMlLogger eventLogger,
-      CustomModel.Factory modelFactory) {
-    this(
-        firebaseOptions,
-        sharedPreferencesUtil,
-        fileDownloadService,
-        modelDownloadService,
-        fileManager,
-        eventLogger,
-        Executors.newSingleThreadExecutor(),
-        modelFactory);
-  }
-
   @VisibleForTesting
+  @RequiresApi(api = VERSION_CODES.KITKAT)
   FirebaseModelDownloader(
       FirebaseOptions firebaseOptions,
       SharedPreferencesUtil sharedPreferencesUtil,
       ModelFileDownloadService fileDownloadService,
       CustomModelDownloadService modelDownloadService,
       ModelFileManager fileManager,
       FirebaseMlLogger eventLogger,
-      Executor executor,
+      @Background Executor bgExecutor,
+      @Blocking Executor blockingExecutor,
       CustomModel.Factory modelFactory) {
     this.firebaseOptions = firebaseOptions;
     this.sharedPreferencesUtil = sharedPreferencesUtil;
     this.fileDownloadService = fileDownloadService;
     this.modelDownloadService = modelDownloadService;
     this.fileManager = fileManager;
     this.eventLogger = eventLogger;
-    this.executor = executor;
+    this.bgExecutor = bgExecutor;
+    this.blockingExecutor = blockingExecutor;
     this.modelFactory = modelFactory;
   }
 
@@ -227,7 +209,7 @@ private Task<CustomModel> getCompletedLocalCustomModelTask(@NonNull CustomModel
 
       if (downloadInProgressTask != null) {
         return downloadInProgressTask.continueWithTask(
-            executor,
+            bgExecutor,
             downloadTask -> {
               if (downloadTask.isSuccessful()) {
                 return finishModelDownload(model.getName());
@@ -251,7 +233,7 @@ private Task<CustomModel> getCompletedLocalCustomModelTask(@NonNull CustomModel
     // bad model state - delete all existing model details and return exception
     return deleteDownloadedModel(model.getName())
         .continueWithTask(
-            executor,
+            bgExecutor,
             deletionTask ->
                 Tasks.forException(
                     new FirebaseMlException(
@@ -284,7 +266,7 @@ private Task<CustomModel> getCustomModelTask(
             firebaseOptions.getProjectId(), modelName, modelHash);
 
     return incomingModelDetails.continueWithTask(
-        executor,
+        bgExecutor,
         incomingModelDetailTask -> {
           if (incomingModelDetailTask.isSuccessful()) {
             // null means we have the latest model or we failed to connect.
@@ -368,7 +350,7 @@ && new File(currentModel.getLocalFilePath()).exists()) {
             return fileDownloadService
                 .download(incomingModelDetailTask.getResult(), conditions)
                 .continueWithTask(
-                    executor,
+                    blockingExecutor,
                     downloadTask -> {
                       if (downloadTask.isSuccessful()) {
                         return finishModelDownload(modelName);
@@ -401,14 +383,14 @@ private Task<CustomModel> retryExpiredUrlDownload(
               firebaseOptions.getProjectId(), modelName);
       // no local model - start download.
       return retryModelDetails.continueWithTask(
-          executor,
+          bgExecutor,
           retryModelDetailTask -> {
             if (retryModelDetailTask.isSuccessful()) {
               // start download
               return fileDownloadService
                   .download(retryModelDetailTask.getResult(), conditions)
                   .continueWithTask(
-                      executor,
+                      bgExecutor,
                       retryDownloadTask -> {
                         if (retryDownloadTask.isSuccessful()) {
                           return finishModelDownload(modelName);
@@ -458,7 +440,7 @@ public Task<Set<CustomModel>> listDownloadedModels() {
     fileDownloadService.maybeCheckDownloadingComplete();
 
     TaskCompletionSource<Set<CustomModel>> taskCompletionSource = new TaskCompletionSource<>();
-    executor.execute(
+    bgExecutor.execute(
         () -> taskCompletionSource.setResult(sharedPreferencesUtil.listDownloadedModels()));
     return taskCompletionSource.getTask();
   }
@@ -472,7 +454,7 @@ public Task<Set<CustomModel>> listDownloadedModels() {
   public Task<Void> deleteDownloadedModel(@NonNull String modelName) {
 
     TaskCompletionSource<Void> taskCompletionSource = new TaskCompletionSource<>();
-    executor.execute(
+    bgExecutor.execute(
         () -> {
           // remove all files associated with this model and then clean up model references.
           boolean isSuccessful = deleteModelDetails(modelName);

firebase-ml-modeldownloader/src/main/java/com/google/firebase/ml/modeldownloader/FirebaseModelDownloaderRegistrar.java

@@ -20,13 +20,17 @@
 import androidx.annotation.RequiresApi;
 import com.google.android.datatransport.TransportFactory;
 import com.google.firebase.FirebaseApp;
+import com.google.firebase.annotations.concurrent.Background;
+import com.google.firebase.annotations.concurrent.Blocking;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.ComponentRegistrar;
 import com.google.firebase.components.Dependency;
+import com.google.firebase.components.Qualified;
 import com.google.firebase.installations.FirebaseInstallationsApi;
 import com.google.firebase.platforminfo.LibraryVersionComponent;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.Executor;
 
 /**
  * Registrar for setting up Firebase ML Model Downloader's dependency injections in Firebase Android
@@ -41,19 +45,25 @@ public class FirebaseModelDownloaderRegistrar implements ComponentRegistrar {
   @NonNull
   @RequiresApi(api = VERSION_CODES.KITKAT)
   public List<Component<?>> getComponents() {
+    Qualified<Executor> bgExecutor = Qualified.qualified(Background.class, Executor.class);
+    Qualified<Executor> blockingExecutor = Qualified.qualified(Blocking.class, Executor.class);
     return Arrays.asList(
         Component.builder(FirebaseModelDownloader.class)
             .name(LIBRARY_NAME)
             .add(Dependency.required(Context.class))
             .add(Dependency.required(FirebaseApp.class))
             .add(Dependency.requiredProvider(FirebaseInstallationsApi.class))
             .add(Dependency.requiredProvider(TransportFactory.class))
+            .add(Dependency.required(bgExecutor))
+            .add(Dependency.required(blockingExecutor))
             .factory(
                 c ->
                     DaggerModelDownloaderComponent.builder()
                         .setApplicationContext(c.get(Context.class))
                         .setFirebaseApp(c.get(FirebaseApp.class))
                         .setFis(c.getProvider(FirebaseInstallationsApi.class))
+                        .setBlockingExecutor(c.get(blockingExecutor))
+                        .setBgExecutor(c.get(bgExecutor))
                         .setTransportFactory(c.getProvider(TransportFactory.class))
                         .build()
                         .getModelDownloader())

firebase-ml-modeldownloader/src/main/java/com/google/firebase/ml/modeldownloader/ModelDownloaderComponent.java

@@ -20,12 +20,15 @@
 import com.google.android.datatransport.TransportFactory;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseOptions;
+import com.google.firebase.annotations.concurrent.Background;
+import com.google.firebase.annotations.concurrent.Blocking;
 import com.google.firebase.inject.Provider;
 import com.google.firebase.installations.FirebaseInstallationsApi;
 import dagger.BindsInstance;
 import dagger.Component;
 import dagger.Module;
 import dagger.Provides;
+import java.util.concurrent.Executor;
 import javax.inject.Named;
 import javax.inject.Singleton;
 
@@ -49,11 +52,18 @@ interface Builder {
     @BindsInstance
     Builder setTransportFactory(Provider<TransportFactory> transportFactory);
 
+    @BindsInstance
+    Builder setBlockingExecutor(@Blocking Executor blockingExecutor);
+
+    @BindsInstance
+    Builder setBgExecutor(@Background Executor bgExecutor);
+
     ModelDownloaderComponent build();
   }
 
   @Module
   interface MainModule {
+
     @Provides
     @Named("persistenceKey")
     static String persistenceKey(FirebaseApp app) {