Add implementation for listDownloadedModels.

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

@@ -55,5 +55,6 @@ dependencies {
     testImplementation 'androidx.test:core:1.3.0'
     testImplementation 'com.google.truth:truth:1.0.1'
     testImplementation 'junit:junit:4.13'
+    testImplementation 'org.mockito:mockito-core:3.3.3'
     testImplementation "org.robolectric:robolectric:$robolectricVersion"
 }

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

@@ -18,18 +18,28 @@
 import androidx.annotation.VisibleForTesting;
 import com.google.android.gms.common.internal.Preconditions;
 import com.google.android.gms.tasks.Task;
+import com.google.android.gms.tasks.Tasks;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseOptions;
+import com.google.firebase.ml.modeldownloader.internal.SharedPreferencesUtil;
 import java.util.Set;
 
 public class FirebaseModelDownloader {
 
   private final FirebaseOptions firebaseOptions;
+  private final SharedPreferencesUtil sharedPreferencesUtil;
 
-  FirebaseModelDownloader(FirebaseOptions firebaseOptions) {
-    this.firebaseOptions = firebaseOptions;
+  FirebaseModelDownloader(FirebaseApp firebaseApp) {
+    this.firebaseOptions = firebaseApp.getOptions();
+    this.sharedPreferencesUtil = new SharedPreferencesUtil(firebaseApp);
   }
 
+  @VisibleForTesting
+  FirebaseModelDownloader(
+      FirebaseOptions firebaseOptions, SharedPreferencesUtil sharedPreferencesUtil) {
+    this.firebaseOptions = firebaseOptions;
+    this.sharedPreferencesUtil = sharedPreferencesUtil;
+  }
   /**
    * Returns the {@link FirebaseModelDownloader} initialized with the default {@link FirebaseApp}.
    *
@@ -84,7 +94,7 @@ public Task<CustomModel> getModel(
   /** @return The set of all models that are downloaded to this device. */
   @NonNull
   public Task<Set<CustomModel>> listDownloadedModels() {
-    throw new UnsupportedOperationException("Not yet implemented.");
+    return Tasks.forResult(sharedPreferencesUtil.listDownloadedModels());
   }
 
   /*

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

@@ -16,7 +16,6 @@
 
 import androidx.annotation.NonNull;
 import com.google.firebase.FirebaseApp;
-import com.google.firebase.FirebaseOptions;
 import com.google.firebase.components.Component;
 import com.google.firebase.components.ComponentRegistrar;
 import com.google.firebase.components.Dependency;
@@ -38,8 +37,7 @@ public List<Component<?>> getComponents() {
     return Arrays.asList(
         Component.builder(FirebaseModelDownloader.class)
             .add(Dependency.required(FirebaseApp.class))
-            .add(Dependency.required(FirebaseOptions.class))
-            .factory(c -> new FirebaseModelDownloader(c.get(FirebaseOptions.class)))
+            .factory(c -> new FirebaseModelDownloader(c.get(FirebaseApp.class)))
             .build(),
         LibraryVersionComponent.create("firebase-ml-modeldownloader", BuildConfig.VERSION_NAME));
   }

firebase-ml-modeldownloader/src/main/java/com/google/firebase/ml/modeldownloader/internal/SharedPreferencesUtil.java

@@ -23,6 +23,10 @@
 import androidx.annotation.VisibleForTesting;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.ml.modeldownloader.CustomModel;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /** @hide */
 public class SharedPreferencesUtil {
@@ -33,6 +37,8 @@ public class SharedPreferencesUtil {
   // local model details
   private static final String LOCAL_MODEL_HASH_PATTERN = "current_model_hash_%s_%s";
   private static final String LOCAL_MODEL_FILE_PATH_PATTERN = "current_model_path_%s_%s";
+  private static final String LOCAL_MODEL_FILE_PATH_MATCHER = "current_model_path_(.*?)_([^/]+)/?";
+
   private static final String LOCAL_MODEL_FILE_SIZE_PATTERN = "current_model_size_%s_%s";
   // details about model during download.
   private static final String DOWNLOADING_MODEL_HASH_PATTERN = "downloading_model_hash_%s_%s";
@@ -190,6 +196,24 @@ public synchronized void clearModelDetails(@NonNull String modelName, boolean cl
         .commit();
   }
 
+  public synchronized Set<CustomModel> listDownloadedModels() {
+    Set<CustomModel> customModels = new HashSet<>();
+    Set<String> keySet = getSharedPreferences().getAll().keySet();
+
+    for (String key : keySet) {
+      // if a local file path is present - get model details.
+      Matcher matcher = Pattern.compile(LOCAL_MODEL_FILE_PATH_MATCHER).matcher(key);
+      if (matcher.find()) {
+        String modelName = matcher.group(matcher.groupCount());
+        CustomModel extractModel = getCustomModelDetails(modelName);
+        if (extractModel != null) {
+          customModels.add(extractModel);
+        }
+      }
+    }
+    return customModels;
+  }
+
   /**
    * Clears all stored data related to a custom model download.
    *

firebase-ml-modeldownloader/src/test/java/com/google/firebase/ml/modeldownloader/FirebaseModelDownloaderTest.java

@@ -14,11 +14,20 @@
 
 package com.google.firebase.ml.modeldownloader;
 
+import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThrows;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 
 import androidx.test.core.app.ApplicationProvider;
+import com.google.android.gms.tasks.Task;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseOptions;
+import com.google.firebase.FirebaseOptions.Builder;
+import com.google.firebase.ml.modeldownloader.internal.SharedPreferencesUtil;
+import java.util.Collections;
+import java.util.Set;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -28,20 +37,28 @@
 public class FirebaseModelDownloaderTest {
 
   public static final String TEST_PROJECT_ID = "777777777777";
+  public static final FirebaseOptions FIREBASE_OPTIONS =
+      new Builder()
+          .setApplicationId("1:123456789:android:abcdef")
+          .setProjectId(TEST_PROJECT_ID)
+          .build();
   public static final String MODEL_NAME = "MODEL_NAME_1";
   public static final CustomModelDownloadConditions DEFAULT_DOWNLOAD_CONDITIONS =
       new CustomModelDownloadConditions.Builder().build();
 
+  public static final String MODEL_HASH = "dsf324";
+  // TODO replace with uploaded model.
+  CustomModel CUSTOM_MODEL = new CustomModel(MODEL_NAME, 0, 100, MODEL_HASH);
+
+  FirebaseModelDownloader firebaseModelDownloader;
+  SharedPreferencesUtil mockPrefs = mock(SharedPreferencesUtil.class);
+
   @Before
   public void setUp() {
     FirebaseApp.clearInstancesForTest();
     // default app
-    FirebaseApp.initializeApp(
-        ApplicationProvider.getApplicationContext(),
-        new FirebaseOptions.Builder()
-            .setApplicationId("1:123456789:android:abcdef")
-            .setProjectId(TEST_PROJECT_ID)
-            .build());
+    FirebaseApp.initializeApp(ApplicationProvider.getApplicationContext(), FIREBASE_OPTIONS);
+    firebaseModelDownloader = new FirebaseModelDownloader(FIREBASE_OPTIONS, mockPrefs);
   }
 
   @Test
@@ -54,10 +71,19 @@ public void getModel_unimplemented() {
   }
 
   @Test
-  public void listDownloadedModels_unimplemented() {
-    assertThrows(
-        UnsupportedOperationException.class,
-        () -> FirebaseModelDownloader.getInstance().listDownloadedModels());
+  public void listDownloadedModels_returnsEmptyModelList() {
+    when(mockPrefs.listDownloadedModels()).thenReturn(Collections.emptySet());
+    Task<Set<CustomModel>> task = firebaseModelDownloader.listDownloadedModels();
+    assertThat(task.isComplete()).isTrue();
+    assertEquals(task.getResult(), Collections.EMPTY_SET);
+  }
+
+  @Test
+  public void listDownloadedModels_returnsModelList() {
+    when(mockPrefs.listDownloadedModels()).thenReturn(Collections.singleton(CUSTOM_MODEL));
+    Task<Set<CustomModel>> task = firebaseModelDownloader.listDownloadedModels();
+    assertThat(task.isComplete()).isTrue();
+    assertEquals(task.getResult(), Collections.singleton(CUSTOM_MODEL));
   }
 
   @Test

firebase-ml-modeldownloader/src/test/java/com/google/firebase/ml/modeldownloader/internal/SharedPreferencesUtilTest.java

@@ -17,11 +17,13 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
 
 import androidx.test.core.app.ApplicationProvider;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseOptions;
 import com.google.firebase.ml.modeldownloader.CustomModel;
+import java.util.Set;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -118,4 +120,43 @@ public void clearDownloadingModelDetails_keepsLocalModel() throws IllegalArgumen
     retrievedModel = sharedPreferencesUtil.getCustomModelDetails(MODEL_NAME);
     assertEquals(retrievedModel, CUSTOM_MODEL_DOWNLOAD_COMPLETE);
   }
+
+  @Test
+  public void listDownloadedModels_localModelFound() throws IllegalArgumentException {
+    sharedPreferencesUtil.setUploadedCustomModelDetails(CUSTOM_MODEL_DOWNLOAD_COMPLETE);
+    Set<CustomModel> retrievedModel = sharedPreferencesUtil.listDownloadedModels();
+    assertEquals(retrievedModel.size(), 1);
+    assertEquals(retrievedModel.iterator().next(), CUSTOM_MODEL_DOWNLOAD_COMPLETE);
+  }
+
+  @Test
+  public void listDownloadedModels_downloadingModelNotFound() throws IllegalArgumentException {
+    sharedPreferencesUtil.setDownloadingCustomModelDetails(CUSTOM_MODEL_DOWNLOADING);
+    assertEquals(sharedPreferencesUtil.listDownloadedModels().size(), 0);
+  }
+
+  @Test
+  public void listDownloadedModels_noModels() throws IllegalArgumentException {
+    assertEquals(sharedPreferencesUtil.listDownloadedModels().size(), 0);
+  }
+
+  @Test
+  public void listDownloadedModels_multipleModels() throws IllegalArgumentException {
+    sharedPreferencesUtil.setUploadedCustomModelDetails(CUSTOM_MODEL_DOWNLOAD_COMPLETE);
+
+    CustomModel model2 =
+        new CustomModel(MODEL_NAME + "2", 0, 102, MODEL_HASH + "2", "file/path/store/ModelName2/1");
+    sharedPreferencesUtil.setUploadedCustomModelDetails(model2);
+
+    CustomModel model3 =
+        new CustomModel(MODEL_NAME + "3", 0, 103, MODEL_HASH + "3", "file/path/store/ModelName3/1");
+
+    sharedPreferencesUtil.setUploadedCustomModelDetails(model3);
+
+    Set<CustomModel> retrievedModel = sharedPreferencesUtil.listDownloadedModels();
+    assertEquals(retrievedModel.size(), 3);
+    assertTrue(retrievedModel.contains(CUSTOM_MODEL_DOWNLOAD_COMPLETE));
+    assertTrue(retrievedModel.contains(model2));
+    assertTrue(retrievedModel.contains(model3));
+  }
 }