Enable use of database storage in CachedContentIndex

It's not yet enabled in the SimpleCache layer, however, so
this is a no-op change.

PiperOrigin-RevId: 233064490

library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndex.java

@@ -102,41 +102,60 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
   }
 
   /**
-   * Creates a CachedContentIndex which works on the index file in the given cacheDir.
+   * Creates an instance supporting database storage only.
    *
-   * @param cacheDir Directory where the index file is kept.
+   * @param databaseProvider Provides the database in which the index is stored.
    */
-  public CachedContentIndex(File cacheDir) {
-    this(cacheDir, null);
+  public CachedContentIndex(DatabaseProvider databaseProvider) {
+    this(
+        databaseProvider,
+        /* legacyStorageDir= */ null,
+        /* legacyStorageSecretKey= */ null,
+        /* legacyStorageEncrypt= */ false,
+        /* preferLegacyStorage= */ false);
   }
 
   /**
-   * Creates a CachedContentIndex which works on the index file in the given cacheDir.
+   * Creates an instance supporting either or both of database and legacy storage.
    *
-   * @param cacheDir Directory where the index file is kept.
-   * @param secretKey 16 byte AES key for reading and writing the cache index.
+   * @param databaseProvider Provides the database in which the index is stored, or {@code null} to
+   *     use only legacy storage.
+   * @param legacyStorageDir The directory in which any legacy storage is stored, or {@code null} to
+   *     use only database storage.
+   * @param legacyStorageSecretKey A 16 byte AES key for reading, and optionally writing, legacy
+   *     storage.
+   * @param legacyStorageEncrypt Whether to encrypt when writing to legacy storage. Must be false if
+   *     {@code secretKey} is null.
+   * @param preferLegacyStorage Whether to use prefer legacy storage if both storage types are
+   *     enabled. This option is only useful for downgrading from database storage back to legacy
+   *     storage.
    */
-  public CachedContentIndex(File cacheDir, @Nullable byte[] secretKey) {
-    this(cacheDir, secretKey, secretKey != null);
-  }
-
-  /**
-   * Creates a CachedContentIndex which works on the index file in the given cacheDir.
-   *
-   * @param cacheDir Directory where the index file is kept.
-   * @param secretKey 16 byte AES key for reading, and optionally writing, the cache index.
-   * @param encrypt Whether the index will be encrypted when written. Must be false if {@code
-   *     secretKey} is null.
-   */
-  public CachedContentIndex(File cacheDir, @Nullable byte[] secretKey, boolean encrypt) {
+  public CachedContentIndex(
+      @Nullable DatabaseProvider databaseProvider,
+      @Nullable File legacyStorageDir,
+      @Nullable byte[] legacyStorageSecretKey,
+      boolean legacyStorageEncrypt,
+      boolean preferLegacyStorage) {
+    Assertions.checkState(databaseProvider != null || legacyStorageDir != null);
     keyToContent = new HashMap<>();
     idToKey = new SparseArray<>();
     removedIds = new SparseBooleanArray();
-    Storage atomicFileStorage =
-        new AtomicFileStorage(new File(cacheDir, FILE_NAME_ATOMIC), secretKey, encrypt);
-    // Storage sqliteStorage = new SQLiteStorage(databaseProvider);
-    storage = atomicFileStorage;
-    previousStorage = null;
+    Storage databaseStorage =
+        databaseProvider != null ? new DatabaseStorage(databaseProvider) : null;
+    Storage legacyStorage =
+        legacyStorageDir != null
+            ? new LegacyStorage(
+                new File(legacyStorageDir, FILE_NAME_ATOMIC),
+                legacyStorageSecretKey,
+                legacyStorageEncrypt)
+            : null;
+    if (databaseStorage == null || (legacyStorage != null && preferLegacyStorage)) {
+      storage = legacyStorage;
+      previousStorage = databaseStorage;
+    } else {
+      storage = databaseStorage;
+      previousStorage = legacyStorage;
+    }
   }
 
   /** Loads the index file. */
@@ -413,7 +432,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
   }
 
   /** {@link Storage} implementation that uses an {@link AtomicFile}. */
-  private static class AtomicFileStorage implements Storage {
+  private static class LegacyStorage implements Storage {
 
     private final boolean encrypt;
     @Nullable private final Cipher cipher;
@@ -424,7 +443,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
     private boolean changed;
     @Nullable private ReusableBufferedOutputStream bufferedOutputStream;
 
-    public AtomicFileStorage(File file, @Nullable byte[] secretKey, boolean encrypt) {
+    public LegacyStorage(File file, @Nullable byte[] secretKey, boolean encrypt) {
       Cipher cipher = null;
       SecretKeySpec secretKeySpec = null;
       if (secretKey != null) {
@@ -436,7 +455,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
           throw new IllegalStateException(e); // Should never happen.
         }
       } else {
-        Assertions.checkArgument(!encrypt);
+        Assertions.checkState(!encrypt);
       }
       this.encrypt = encrypt;
       this.cipher = cipher;
@@ -642,7 +661,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
   }
 
   /** {@link Storage} implementation that uses an SQL database. */
-  private static final class SQLiteStorage implements Storage {
+  private static final class DatabaseStorage implements Storage {
 
     private static final String TABLE_NAME = DatabaseProvider.TABLE_PREFIX + "CacheContentMetadata";
     private static final int TABLE_VERSION = 1;
@@ -674,7 +693,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
     private final DatabaseProvider databaseProvider;
     private final SparseArray<CachedContent> pendingUpdates;
 
-    public SQLiteStorage(DatabaseProvider databaseProvider) {
+    public DatabaseStorage(DatabaseProvider databaseProvider) {
       this.databaseProvider = databaseProvider;
       pendingUpdates = new SparseArray<>();
     }

library/core/src/main/java/com/google/android/exoplayer2/upstream/cache/SimpleCache.java

@@ -125,7 +125,15 @@ public final class SimpleCache implements Cache {
    *     secretKey} is null.
    */
   public SimpleCache(File cacheDir, CacheEvictor evictor, byte[] secretKey, boolean encrypt) {
-    this(cacheDir, evictor, new CachedContentIndex(cacheDir, secretKey, encrypt));
+    this(
+        cacheDir,
+        evictor,
+        new CachedContentIndex(
+            /* databaseProvider= */ null,
+            cacheDir,
+            secretKey,
+            encrypt,
+            /* preferLegacyStorage= */ true));
   }
 
   /**

library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CachedContentIndexTest.java

@@ -19,8 +19,10 @@ import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 
 import android.net.Uri;
+import android.support.annotation.Nullable;
 import android.util.SparseArray;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileInputStream;
@@ -73,14 +75,12 @@ public class CachedContentIndexTest {
       0, 0, 0, 0, 0, 0, 10, 0, // original_content_length
       0x12, 0x15, 0x66, (byte) 0x8A // hashcode_of_CachedContent_array
   };
-  private CachedContentIndex index;
   private File cacheDir;
 
   @Before
   public void setUp() throws Exception {
     cacheDir =
         Util.createTempDirectory(RuntimeEnvironment.application, "ExoPlayerTest");
-    index = new CachedContentIndex(cacheDir);
   }
 
   @After
@@ -94,6 +94,8 @@ public class CachedContentIndexTest {
     final String key2 = "key2";
     final String key3 = "key3";
 
+    CachedContentIndex index = newInstance();
+
     // Add two CachedContents with add methods
     CachedContent cachedContent1 = index.getOrAdd(key1);
     CachedContent cachedContent2 = index.getOrAdd(key2);
@@ -145,12 +147,14 @@ public class CachedContentIndexTest {
   }
 
   @Test
-  public void testStoreAndLoad() throws Exception {
-    assertStoredAndLoadedEqual(index, new CachedContentIndex(cacheDir));
+  public void testLegacyStoreAndLoad() throws Exception {
+    assertStoredAndLoadedEqual(newLegacyInstance(), newLegacyInstance());
   }
 
   @Test
-  public void testLoadV1() throws Exception {
+  public void testLegacyLoadV1() throws Exception {
+    CachedContentIndex index = newLegacyInstance();
+
     FileOutputStream fos =
         new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC));
     fos.write(testIndexV1File);
@@ -169,7 +173,9 @@ public class CachedContentIndexTest {
   }
 
   @Test
-  public void testLoadV2() throws Exception {
+  public void testLegacyLoadV2() throws Exception {
+    CachedContentIndex index = newLegacyInstance();
+
     FileOutputStream fos =
         new FileOutputStream(new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC));
     fos.write(testIndexV2File);
@@ -190,6 +196,7 @@ public class CachedContentIndexTest {
 
   @Test
   public void testAssignIdForKeyAndGetKeyForId() {
+    CachedContentIndex index = newInstance();
     final String key1 = "key1";
     final String key2 = "key2";
     int id1 = index.assignIdForKey(key1);
@@ -214,12 +221,11 @@ public class CachedContentIndexTest {
   }
 
   @Test
-  public void testEncryption() throws Exception {
+  public void testLegacyEncryption() throws Exception {
     byte[] key = "Bar12345Bar12345".getBytes(C.UTF8_NAME); // 128 bit key
     byte[] key2 = "Foo12345Foo12345".getBytes(C.UTF8_NAME); // 128 bit key
 
-    assertStoredAndLoadedEqual(
-        new CachedContentIndex(cacheDir, key), new CachedContentIndex(cacheDir, key));
+    assertStoredAndLoadedEqual(newLegacyInstance(key), newLegacyInstance(key));
 
     // Rename the index file from the test above
     File file1 = new File(cacheDir, CachedContentIndex.FILE_NAME_ATOMIC);
@@ -227,8 +233,7 @@ public class CachedContentIndexTest {
     assertThat(file1.renameTo(file2)).isTrue();
 
     // Write a new index file
-    assertStoredAndLoadedEqual(
-        new CachedContentIndex(cacheDir, key), new CachedContentIndex(cacheDir, key));
+    assertStoredAndLoadedEqual(newLegacyInstance(key), newLegacyInstance(key));
 
     assertThat(file1.length()).isEqualTo(file2.length());
     // Assert file content is different
@@ -240,8 +245,7 @@ public class CachedContentIndexTest {
 
     boolean threw = false;
     try {
-      assertStoredAndLoadedEqual(
-          new CachedContentIndex(cacheDir, key), new CachedContentIndex(cacheDir, key2));
+      assertStoredAndLoadedEqual(newLegacyInstance(key), newLegacyInstance(key2));
     } catch (AssertionError e) {
       threw = true;
     }
@@ -250,8 +254,7 @@ public class CachedContentIndexTest {
         .isTrue();
 
     try {
-      assertStoredAndLoadedEqual(
-          new CachedContentIndex(cacheDir, key), new CachedContentIndex(cacheDir));
+      assertStoredAndLoadedEqual(newLegacyInstance(key), newLegacyInstance());
     } catch (AssertionError e) {
       threw = true;
     }
@@ -260,18 +263,18 @@ public class CachedContentIndexTest {
         .isTrue();
 
     // Non encrypted index file can be read even when encryption key provided.
-    assertStoredAndLoadedEqual(
-        new CachedContentIndex(cacheDir), new CachedContentIndex(cacheDir, key));
+    assertStoredAndLoadedEqual(newLegacyInstance(), newLegacyInstance(key));
 
     // Test multiple store() calls
-    CachedContentIndex index = new CachedContentIndex(cacheDir, key);
+    CachedContentIndex index = newLegacyInstance(key);
     index.getOrAdd("key3");
     index.store();
-    assertStoredAndLoadedEqual(index, new CachedContentIndex(cacheDir, key));
+    assertStoredAndLoadedEqual(index, newLegacyInstance(key));
   }
 
   @Test
   public void testRemoveEmptyNotLockedCachedContent() {
+    CachedContentIndex index = newInstance();
     CachedContent cachedContent = index.getOrAdd("key1");
 
     index.maybeRemove(cachedContent.key);
@@ -281,6 +284,8 @@ public class CachedContentIndexTest {
 
   @Test
   public void testCantRemoveNotEmptyCachedContent() throws Exception {
+    CachedContentIndex index = newInstance();
+
     CachedContent cachedContent = index.getOrAdd("key1");
     long cacheFileLength = 20;
     File cacheFile =
@@ -300,6 +305,7 @@ public class CachedContentIndexTest {
 
   @Test
   public void testCantRemoveLockedCachedContent() {
+    CachedContentIndex index = newInstance();
     CachedContent cachedContent = index.getOrAdd("key1");
     cachedContent.setLocked(true);
 
@@ -327,4 +333,21 @@ public class CachedContentIndexTest {
       assertThat(index2.get(key)).isEqualTo(index.get(key));
     }
   }
+
+  private CachedContentIndex newInstance() {
+    return new CachedContentIndex(TestUtil.getTestDatabaseProvider());
+  }
+
+  private CachedContentIndex newLegacyInstance() {
+    return newLegacyInstance(null);
+  }
+
+  private CachedContentIndex newLegacyInstance(@Nullable byte[] key) {
+    return new CachedContentIndex(
+        /* databaseProvider= */ null,
+        cacheDir,
+        /* legacyStorageSecretKey= */ key,
+        /* legacyStorageEncrypt= */ key != null,
+        /* preferLegacyStorage= */ true);
+  }
 }

library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/CachedRegionTrackerTest.java

@@ -21,6 +21,7 @@ import static org.mockito.Mockito.anyString;
 import static org.mockito.Mockito.when;
 
 import com.google.android.exoplayer2.extractor.ChunkIndex;
+import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileOutputStream;
@@ -64,7 +65,7 @@ public final class CachedRegionTrackerTest {
     when(cache.addListener(anyString(), any(Cache.Listener.class))).thenReturn(new TreeSet<>());
     tracker = new CachedRegionTracker(cache, CACHE_KEY, CHUNK_INDEX);
     cacheDir = Util.createTempDirectory(RuntimeEnvironment.application, "ExoPlayerTest");
-    index = new CachedContentIndex(cacheDir);
+    index = new CachedContentIndex(TestUtil.getTestDatabaseProvider());
   }
 
   @After

library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheSpanTest.java

@@ -18,6 +18,7 @@ package com.google.android.exoplayer2.upstream.cache;
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.common.truth.Truth.assertWithMessage;
 
+import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.util.Util;
 import java.io.File;
 import java.io.FileOutputStream;
@@ -51,7 +52,7 @@ public class SimpleCacheSpanTest {
   public void setUp() throws Exception {
     cacheDir =
         Util.createTempDirectory(RuntimeEnvironment.application, "ExoPlayerTest");
-    index = new CachedContentIndex(cacheDir);
+    index = new CachedContentIndex(TestUtil.getTestDatabaseProvider());
   }
 
   @After

library/core/src/test/java/com/google/android/exoplayer2/upstream/cache/SimpleCacheTest.java

@@ -22,6 +22,7 @@ import static com.google.common.truth.Truth.assertWithMessage;
 import static org.mockito.Mockito.doAnswer;
 
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.upstream.cache.Cache.CacheException;
 import com.google.android.exoplayer2.util.Util;
 import java.io.File;
@@ -293,7 +294,8 @@ public class SimpleCacheTest {
   /* Tests https://github.com/google/ExoPlayer/issues/3260 case. */
   @Test
   public void testExceptionDuringEvictionByLeastRecentlyUsedCacheEvictorNotHang() throws Exception {
-    CachedContentIndex index = Mockito.spy(new CachedContentIndex(cacheDir));
+    CachedContentIndex index =
+        Mockito.spy(new CachedContentIndex(TestUtil.getTestDatabaseProvider()));
     SimpleCache simpleCache =
         new SimpleCache(cacheDir, new LeastRecentlyUsedCacheEvictor(20), index);
 

testutils/src/main/java/com/google/android/exoplayer2/testutil/TestUtil.java

@@ -19,11 +19,15 @@ import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.fail;
 
 import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.graphics.Color;
 import android.net.Uri;
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.database.DatabaseProvider;
+import com.google.android.exoplayer2.database.DefaultDatabaseProvider;
 import com.google.android.exoplayer2.extractor.DefaultExtractorInput;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.ExtractorInput;
@@ -155,6 +159,23 @@ public class TestUtil {
     return BitmapFactory.decodeStream(getInputStream(context, fileName));
   }
 
+  public static DatabaseProvider getTestDatabaseProvider() {
+    // Provides an in-memory database.
+    return new DefaultDatabaseProvider(
+        new SQLiteOpenHelper(
+            /* context= */ null, /* name= */ null, /* factory= */ null, /* version= */ 1) {
+          @Override
+          public void onCreate(SQLiteDatabase db) {
+            // Do nothing.
+          }
+
+          @Override
+          public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+            // Do nothing.
+          }
+        });
+  }
+
   /**
    * Asserts that data read from a {@link DataSource} matches {@code expected}.
    *