1 /* 2 * Copyright 2022 Google LLC 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.android.libraries.mobiledatadownload.internal.util; 17 18 import android.content.Context; 19 import android.util.Base64; 20 import com.google.android.libraries.mobiledatadownload.internal.logging.LogUtil; 21 import com.google.common.base.Optional; 22 import com.google.common.collect.ImmutableList; 23 import com.google.protobuf.InvalidProtocolBufferException; 24 import com.google.mobiledatadownload.internal.MetadataProto.DataFileGroupInternal; 25 import com.google.mobiledatadownload.internal.MetadataProto.GroupKey; 26 import java.io.File; 27 import java.io.FileInputStream; 28 import java.io.FileNotFoundException; 29 import java.io.IOException; 30 import java.nio.ByteBuffer; 31 import java.util.List; 32 33 /** Stores and provides access to file group metadata using SharedPreferences. */ 34 public final class FileGroupsMetadataUtil { 35 36 private static final String TAG = "FileGroupsMetadataUtil"; 37 38 // Name of file groups SharedPreferences. 39 public static final String MDD_FILE_GROUPS = "gms_icing_mdd_groups"; 40 41 // Name of file groups group key properties SharedPreferences. 42 public static final String MDD_FILE_GROUP_KEY_PROPERTIES = "gms_icing_mdd_group_key_properties"; 43 44 // TODO(b/144033163): Migrate the Garbage Collector File to PDS. 45 public static final String MDD_GARBAGE_COLLECTION_FILE = "gms_icing_mdd_garbage_file"; 46 47 /** Group key Deserialization exception. */ 48 public static class GroupKeyDeserializationException extends Exception { GroupKeyDeserializationException(String msg, Throwable cause)49 GroupKeyDeserializationException(String msg, Throwable cause) { 50 super(msg, cause); 51 } 52 } 53 54 // TODO(b/144033163): Migrate the Garbage Collector File to PDS. getAllStaleGroups(File garbageCollectorFile)55 public static List<DataFileGroupInternal> getAllStaleGroups(File garbageCollectorFile) { 56 FileInputStream inputStream; 57 try { 58 inputStream = new FileInputStream(garbageCollectorFile); 59 } catch (FileNotFoundException e) { 60 LogUtil.d("File %s not found while reading.", garbageCollectorFile.getAbsolutePath()); 61 return ImmutableList.of(); 62 } 63 64 ByteBuffer buf; 65 try { 66 buf = ByteBuffer.allocate((int) garbageCollectorFile.length()); 67 } catch (IllegalArgumentException e) { 68 LogUtil.e(e, "%s: Exception while reading from stale groups into buffer.", TAG); 69 return ImmutableList.of(); 70 } 71 72 List<DataFileGroupInternal> fileGroups = null; 73 try { 74 inputStream.getChannel().read(buf); 75 // Rewind so that we can read from the start of the buffer. 76 buf.rewind(); 77 // tail_crc == false, means that each message has its own crc 78 fileGroups = 79 ProtoLiteUtil.readFromBuffer( 80 buf, DataFileGroupInternal.class, DataFileGroupInternal.parser(), false /*tail crc*/); 81 inputStream.close(); 82 } catch (IOException e) { 83 LogUtil.e(e, "%s: IOException occurred while reading file groups.", TAG); 84 } 85 return fileGroups == null ? ImmutableList.of() : fileGroups; 86 } 87 getGarbageCollectorFile(Context context, Optional<String> instanceId)88 public static File getGarbageCollectorFile(Context context, Optional<String> instanceId) { 89 String fileName = 90 instanceId != null && instanceId.isPresent() 91 ? MDD_GARBAGE_COLLECTION_FILE + instanceId.get() 92 : MDD_GARBAGE_COLLECTION_FILE; 93 return new File(context.getFilesDir(), fileName); 94 } 95 96 // TODO(b/129702287): Move away from proto based serialization. getSerializedGroupKey(GroupKey groupKey)97 public static String getSerializedGroupKey(GroupKey groupKey) { 98 byte[] byteValue = groupKey.toByteArray(); 99 return Base64.encodeToString(byteValue, Base64.NO_PADDING | Base64.NO_WRAP); 100 } 101 102 /** 103 * Converts a string representing a serialized GroupKey into a GroupKey. 104 * 105 * @return groupKey if able to parse string key properly. 106 * @throws GroupKeyDeserializationException when unable to parse string key 107 */ 108 // TODO(b/129702287): Move away from proto based deserialization. deserializeGroupKey(String serializedGroupKey)109 public static GroupKey deserializeGroupKey(String serializedGroupKey) 110 throws GroupKeyDeserializationException { 111 try { 112 return SharedPreferencesUtil.parseLiteFromEncodedString( 113 serializedGroupKey, GroupKey.parser()); 114 } catch (NullPointerException | InvalidProtocolBufferException e) { 115 throw new GroupKeyDeserializationException( 116 "Failed to deserialize key:" + serializedGroupKey, e); 117 } 118 } 119 FileGroupsMetadataUtil()120 private FileGroupsMetadataUtil() {} 121 } 122