Store loaded indexes in persistent storage.

Signed-off-by: Yahor Berdnikau <egorr.berd@gmail.com>

cache/src/main/kotlin/org/moire/ultrasonic/cache/serializers/ArtistSerializer.kt

@@ -0,0 +1,60 @@
+@file:JvmMultifileClass
+@file:JvmName("DomainSerializers")
+package org.moire.ultrasonic.cache.serializers
+
+import com.twitter.serial.serializer.CollectionSerializers
+import com.twitter.serial.serializer.ObjectSerializer
+import com.twitter.serial.serializer.SerializationContext
+import com.twitter.serial.stream.SerializerDefs
+import com.twitter.serial.stream.SerializerInput
+import com.twitter.serial.stream.SerializerOutput
+import org.moire.ultrasonic.domain.Artist
+
+private const val SERIALIZER_VERSION = 1
+
+/**
+ * Serializer/deserializer for [Artist] domain entity.
+ */
+val artistSerializer get() = object : ObjectSerializer<Artist>(SERIALIZER_VERSION) {
+    override fun serializeObject(
+            context: SerializationContext,
+            output: SerializerOutput<out SerializerOutput<*>>,
+            item: Artist
+    ) {
+        output.writeString(item.id)
+                .writeString(item.name)
+                .writeString(item.index)
+                .writeString(item.coverArt)
+                .apply {
+                    val albumCount = item.albumCount
+                    if (albumCount != null) writeLong(albumCount) else writeNull()
+                }
+                .writeInt(item.closeness)
+    }
+
+    override fun deserializeObject(
+            context: SerializationContext,
+            input: SerializerInput,
+            versionNumber: Int
+    ): Artist? {
+        if (versionNumber != SERIALIZER_VERSION) return null
+
+        val id = input.readString()
+        val name = input.readString()
+        val index = input.readString()
+        val coverArt = input.readString()
+        val albumCount = if (input.peekType() == SerializerDefs.TYPE_NULL) {
+            input.readNull()
+            null
+        } else {
+            input.readLong()
+        }
+        val closeness = input.readInt()
+        return Artist(id, name, index, coverArt, albumCount, closeness)
+    }
+}
+
+/**
+ * Serializer/deserializer for list of [Artist] domain entities.
+ */
+val artistListSerializer = CollectionSerializers.getListSerializer(artistSerializer)

cache/src/main/kotlin/org/moire/ultrasonic/cache/serializers/IndexesSerializer.kt

@@ -0,0 +1,44 @@
+@file:JvmMultifileClass
+@file:JvmName("DomainSerializers")
+package org.moire.ultrasonic.cache.serializers
+
+import com.twitter.serial.serializer.CollectionSerializers
+import com.twitter.serial.serializer.ObjectSerializer
+import com.twitter.serial.serializer.SerializationContext
+import com.twitter.serial.stream.SerializerInput
+import com.twitter.serial.stream.SerializerOutput
+import org.moire.ultrasonic.domain.Artist
+import org.moire.ultrasonic.domain.Indexes
+
+private const val SERIALIZATION_VERSION = 1
+
+val indexesSerializer get() = object : ObjectSerializer<Indexes>(SERIALIZATION_VERSION) {
+    override fun serializeObject(
+            context: SerializationContext,
+            output: SerializerOutput<out SerializerOutput<*>>,
+            item: Indexes
+    ) {
+        output.writeLong(item.lastModified)
+                .writeString(item.ignoredArticles)
+                .writeObject<MutableList<Artist>>(context, item.shortcuts,
+                        CollectionSerializers.getListSerializer(artistSerializer))
+                .writeObject<MutableList<Artist>>(context, item.artists,
+                        CollectionSerializers.getListSerializer(artistSerializer))
+    }
+
+    override fun deserializeObject(
+            context: SerializationContext,
+            input: SerializerInput,
+            versionNumber: Int
+    ): Indexes? {
+        if (versionNumber != SERIALIZATION_VERSION) return null
+
+        val lastModified = input.readLong()
+        val ignoredArticles = input.readString() ?: return null
+        val shortcutsList = input.readObject(context,
+                CollectionSerializers.getListSerializer(artistSerializer)) ?: return null
+        val artistsList = input.readObject(context,
+                CollectionSerializers.getListSerializer(artistSerializer)) ?: return null
+        return Indexes(lastModified, ignoredArticles, shortcutsList, artistsList)
+    }
+}

cache/src/test/kotlin/org/moire/ultrasonic/cache/BaseStorageTest.kt

@@ -1,6 +1,7 @@
 package org.moire.ultrasonic.cache
 
 import com.nhaarman.mockito_kotlin.mock
+import com.twitter.serial.util.SerializationUtils
 import org.amshove.kluent.`it returns`
 import org.junit.Before
 import org.junit.Rule
@@ -31,4 +32,9 @@ abstract class BaseStorageTest {
     }
 
     protected val storageDir get() = File(mockDirectories.getInternalDataDir(), STORAGE_DIR_NAME)
+
+    protected fun validateSerializedData(index: Int = 0) {
+        val serializedFileBytes = storageDir.listFiles()[index].readBytes()
+        SerializationUtils.validateSerializedData(serializedFileBytes)
+    }
 }

cache/src/test/kotlin/org/moire/ultrasonic/cache/serializers/ArtistSerializerTest.kt

@@ -0,0 +1,57 @@
+package org.moire.ultrasonic.cache.serializers
+
+import org.amshove.kluent.`should equal`
+import org.junit.Test
+import org.moire.ultrasonic.cache.BaseStorageTest
+import org.moire.ultrasonic.domain.Artist
+
+/**
+ * [Artist] serializers test.
+ */
+class ArtistSerializerTest : BaseStorageTest() {
+    @Test
+    fun `Should correctly serialize Artist object`() {
+        val item = Artist("id", "name", "index", "coverArt", 1, 0)
+
+        storage.store("some-name", item, artistSerializer)
+
+        validateSerializedData()
+    }
+
+    @Test
+    fun `Should correctly deserialize Artist object`() {
+        val itemName = "some-name"
+        val item = Artist("id", "name", "index", "coverArt", null, 0)
+        storage.store(itemName, item, artistSerializer)
+
+        val loadedItem = storage.load(itemName, artistSerializer)
+
+        loadedItem `should equal` item
+    }
+
+    @Test
+    fun `Should correctly serialize list of Artists`() {
+        val itemsList = listOf(
+                Artist(id = "1"),
+                Artist(id = "2", name = "some")
+        )
+
+        storage.store("some-name", itemsList, artistListSerializer)
+
+        validateSerializedData()
+    }
+
+    @Test
+    fun `Should correctly deserialize list of Artists`() {
+        val name = "some-name"
+        val itemsList = listOf(
+                Artist(id = "1"),
+                Artist(id = "2", name = "some")
+        )
+        storage.store(name, itemsList, artistListSerializer)
+
+        val loadedItems = storage.load(name, artistListSerializer)
+
+        loadedItems `should equal` itemsList
+    }
+}

cache/src/test/kotlin/org/moire/ultrasonic/cache/serializers/IndexesSerializerTest.kt

@@ -0,0 +1,40 @@
+package org.moire.ultrasonic.cache.serializers
+
+import org.amshove.kluent.`should equal`
+import org.junit.Test
+import org.moire.ultrasonic.cache.BaseStorageTest
+import org.moire.ultrasonic.domain.Artist
+import org.moire.ultrasonic.domain.Indexes
+
+/**
+ * Test [Indexes] domain entity serializer.
+ */
+class IndexesSerializerTest : BaseStorageTest() {
+    @Test
+    fun `Should correctly serialize Indexes object`() {
+        val item = Indexes(220L, "", mutableListOf(
+                Artist("12")
+        ), mutableListOf(
+                Artist("233", "some")
+        ))
+
+        storage.store("some-name", item, indexesSerializer)
+
+        validateSerializedData()
+    }
+
+    @Test
+    fun `Should correctly deserialize Indexes object`() {
+        val name = "some-name"
+        val item = Indexes(220L, "", mutableListOf(
+                Artist("12")
+        ), mutableListOf(
+                Artist("233", "some")
+        ))
+        storage.store(name, item, indexesSerializer)
+
+        val loadedItem = storage.load(name, indexesSerializer)
+
+        loadedItem `should equal` item
+    }
+}

cache/src/test/kotlin/org/moire/ultrasonic/cache/serializers/MusicFolderSerializerTest.kt

@@ -1,6 +1,5 @@
 package org.moire.ultrasonic.cache.serializers
 
-import com.twitter.serial.util.SerializationUtils
 import org.amshove.kluent.`should equal`
 import org.junit.Test
 import org.moire.ultrasonic.cache.BaseStorageTest
@@ -16,8 +15,7 @@ class MusicFolderSerializerTest : BaseStorageTest() {
 
         storage.store("some-name", item, musicFolderSerializer)
 
-        val serializedFileBytes = storageDir.listFiles()[0].readBytes()
-        SerializationUtils.validateSerializedData(serializedFileBytes)
+        validateSerializedData()
     }
 
     @Test
@@ -40,8 +38,7 @@ class MusicFolderSerializerTest : BaseStorageTest() {
 
         storage.store("some-name", itemsList, musicFolderListSerializer)
 
-        val serializedFileBytes = storageDir.listFiles()[0].readBytes()
-        SerializationUtils.validateSerializedData(serializedFileBytes)
+        validateSerializedData()
     }
 
     @Test

ultrasonic/src/main/java/org/moire/ultrasonic/service/RESTMusicService.java

@@ -120,6 +120,7 @@ public class RESTMusicService implements MusicService {
     private static final String TAG = RESTMusicService.class.getSimpleName();
 
     private static final String MUSIC_FOLDER_STORAGE_NAME = "music_folder";
+    private static final String INDEXES_STORAGE_NAME = "indexes";
 
     private final SubsonicAPIClient subsonicAPIClient;
     private final PermanentFileStorage fileStorage;
@@ -155,8 +156,8 @@ public class RESTMusicService implements MusicService {
     public List<MusicFolder> getMusicFolders(boolean refresh,
                                              Context context,
                                              ProgressListener progressListener) throws Exception {
-        List<MusicFolder> cachedMusicFolders = fileStorage
-                .load(MUSIC_FOLDER_STORAGE_NAME, DomainSerializers.getMusicFolderListSerializer());
+        List<MusicFolder> cachedMusicFolders = fileStorage.load(MUSIC_FOLDER_STORAGE_NAME,
+                DomainSerializers.getMusicFolderListSerializer());
         if (cachedMusicFolders != null && !refresh) {
             return cachedMusicFolders;
         }
@@ -177,7 +178,8 @@ public class RESTMusicService implements MusicService {
                               boolean refresh,
                               Context context,
                               ProgressListener progressListener) throws Exception {
-        Indexes cachedIndexes = readCachedIndexes(context, musicFolderId);
+        Indexes cachedIndexes = fileStorage.load(INDEXES_STORAGE_NAME,
+                DomainSerializers.getIndexesSerializer());
         if (cachedIndexes != null && !refresh) {
             return cachedIndexes;
         }
@@ -188,25 +190,10 @@ public class RESTMusicService implements MusicService {
         checkResponseSuccessful(response);
 
         Indexes indexes = APIIndexesConverter.toDomainEntity(response.body().getIndexes());
-        writeCachedIndexes(context, indexes, musicFolderId);
+        fileStorage.store(INDEXES_STORAGE_NAME, indexes, DomainSerializers.getIndexesSerializer());
         return indexes;
     }
 
-    private static Indexes readCachedIndexes(Context context, String musicFolderId) {
-        String filename = getCachedIndexesFilename(context, musicFolderId);
-        return FileUtil.deserialize(context, filename);
-    }
-
-    private static void writeCachedIndexes(Context context, Indexes indexes, String musicFolderId) {
-        String filename = getCachedIndexesFilename(context, musicFolderId);
-        FileUtil.serialize(context, indexes, filename);
-    }
-
-    private static String getCachedIndexesFilename(Context context, String musicFolderId) {
-        String s = Util.getRestUrl(context, null) + musicFolderId;
-        return String.format(Locale.US, "indexes-%d.ser", Math.abs(s.hashCode()));
-    }
-
     @Override
     public Indexes getArtists(boolean refresh,
                               Context context,