Implement resumable downloads.

libsignal/service/src/main/java/org/whispersystems/signalservice/api/SignalServiceMessageReceiver.java

@@ -134,7 +134,8 @@ public class SignalServiceMessageReceiver {
    *
    * @param pointer The {@link SignalServiceAttachmentPointer}
    *                received in a {@link SignalServiceDataMessage}.
-   * @param destination The download destination for this attachment.
+   * @param destination The download destination for this attachment. If this file exists, it is
+   *                    assumed that this is previously-downloaded content that can be resumed.
    * @param listener An optional listener (may be null) to receive callbacks on download progress.
    *
    * @return An InputStream that streams the plaintext attachment contents.

libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java

@@ -506,7 +506,7 @@ public class PushServiceSocket {
     String                hexPackId = Hex.toStringCondensed(packId);
     ByteArrayOutputStream output    = new ByteArrayOutputStream();
 
-    downloadFromCdn(output, String.format(Locale.US, STICKER_PATH, hexPackId, stickerId), 1024 * 1024, null);
+    downloadFromCdn(output, 0, String.format(Locale.US, STICKER_PATH, hexPackId, stickerId), 1024 * 1024, null);
 
     return output.toByteArray();
   }
@@ -517,7 +517,7 @@ public class PushServiceSocket {
     String                hexPackId = Hex.toStringCondensed(packId);
     ByteArrayOutputStream output    = new ByteArrayOutputStream();
 
-    downloadFromCdn(output, String.format(STICKER_MANIFEST_PATH, hexPackId), 1024 * 1024, null);
+    downloadFromCdn(output, 0, String.format(STICKER_MANIFEST_PATH, hexPackId), 1024 * 1024, null);
 
     return output.toByteArray();
   }
@@ -771,14 +771,14 @@ public class PushServiceSocket {
   private void downloadFromCdn(File destination, String path, int maxSizeBytes, ProgressListener listener)
       throws PushNetworkException, NonSuccessfulResponseCodeException
   {
-    try (FileOutputStream outputStream = new FileOutputStream(destination)) {
+    try (FileOutputStream outputStream = new FileOutputStream(destination, true)) {
-      downloadFromCdn(outputStream, path, maxSizeBytes, listener);
+      downloadFromCdn(outputStream, destination.length(), path, maxSizeBytes, listener);
     } catch (IOException e) {
       throw new PushNetworkException(e);
     }
   }
 
-  private void downloadFromCdn(OutputStream outputStream, String path, int maxSizeBytes, ProgressListener listener)
+  private void downloadFromCdn(OutputStream outputStream, long offset, String path, int maxSizeBytes, ProgressListener listener)
       throws PushNetworkException, NonSuccessfulResponseCodeException
   {
     ConnectionHolder connectionHolder = getRandom(cdnClients, random);
@@ -794,19 +794,25 @@ public class PushServiceSocket {
       request.addHeader("Host", connectionHolder.getHostHeader().get());
     }
 
+    if (offset > 0) {
+      Log.i(TAG, "Starting download from CDN with offset " + offset);
+      request.addHeader("Range", "bytes=" + offset + "-");
+    }
+
     Call call = okHttpClient.newCall(request.build());
 
     synchronized (connections) {
       connections.add(call);
     }
 
-    Response response;
+    Response     response = null;
+    ResponseBody body     = null;
 
     try {
       response = call.execute();
 
       if (response.isSuccessful()) {
-        ResponseBody body = response.body();
+        body = response.body();
 
         if (body == null)                        throw new PushNetworkException("No response body!");
         if (body.contentLength() > maxSizeBytes) throw new PushNetworkException("Response exceeds max size!");
@@ -814,20 +820,24 @@ public class PushServiceSocket {
         InputStream  in     = body.byteStream();
         byte[]       buffer = new byte[32768];
 
-        int read, totalRead = 0;
+        int  read      = 0;
+        long totalRead = offset;
 
         while ((read = in.read(buffer, 0, buffer.length)) != -1) {
           outputStream.write(buffer, 0, read);
           if ((totalRead += read) > maxSizeBytes) throw new PushNetworkException("Response exceeded max size!");
 
           if (listener != null) {
-            listener.onAttachmentProgress(body.contentLength(), totalRead);
+            listener.onAttachmentProgress(body.contentLength() + offset, totalRead);
           }
         }
 
         return;
       }
     } catch (IOException e) {
+      if (body != null) {
+        body.close();
+      }
       throw new PushNetworkException(e);
     } finally {
       synchronized (connections) {

src/org/thoughtcrime/securesms/database/AttachmentDatabase.java

@@ -57,6 +57,7 @@ import org.thoughtcrime.securesms.stickers.StickerLocator;
 import org.thoughtcrime.securesms.util.Base64;
 import org.thoughtcrime.securesms.util.BitmapDecodingException;
 import org.thoughtcrime.securesms.util.BitmapUtil;
+import org.thoughtcrime.securesms.util.FileUtils;
 import org.thoughtcrime.securesms.util.JsonUtils;
 import org.thoughtcrime.securesms.util.MediaMetadataRetrieverUtil;
 import org.thoughtcrime.securesms.util.MediaUtil;
@@ -98,6 +99,7 @@ public class AttachmentDatabase extends Database {
           static final String CONTENT_LOCATION       = "cl";
   public  static final String DATA                   = "_data";
           static final String TRANSFER_STATE         = "pending_push";
+  private static final String TRANSFER_FILE          = "transfer_file";
   public  static final String SIZE                   = "data_size";
           static final String FILE_NAME              = "file_name";
   public  static final String THUMBNAIL              = "thumbnail";
@@ -136,7 +138,7 @@ public class AttachmentDatabase extends Database {
                                                            UNIQUE_ID, DIGEST, FAST_PREFLIGHT_ID, VOICE_NOTE,
                                                            QUOTE, DATA_RANDOM, THUMBNAIL_RANDOM, WIDTH, HEIGHT,
                                                            CAPTION, STICKER_PACK_ID, STICKER_PACK_KEY, STICKER_ID,
-                                                           DATA_HASH, BLUR_HASH, TRANSFORM_PROPERTIES};
+                                                           DATA_HASH, BLUR_HASH, TRANSFORM_PROPERTIES, TRANSFER_FILE };
 
   public static final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + " (" + ROW_ID + " INTEGER PRIMARY KEY, " +
     MMS_ID + " INTEGER, " + "seq" + " INTEGER DEFAULT 0, "                        +
@@ -152,7 +154,7 @@ public class AttachmentDatabase extends Database {
     CAPTION + " TEXT DEFAULT NULL, " + STICKER_PACK_ID + " TEXT DEFAULT NULL, " +
     STICKER_PACK_KEY + " DEFAULT NULL, " + STICKER_ID + " INTEGER DEFAULT -1, " +
     DATA_HASH + " TEXT DEFAULT NULL, " + BLUR_HASH + " TEXT DEFAULT NULL, " +
-    TRANSFORM_PROPERTIES + " TEXT DEFAULT NULL);";
+    TRANSFORM_PROPERTIES + " TEXT DEFAULT NULL, " + TRANSFER_FILE + " TEXT DEFAULT NULL);";
 
   public static final String[] CREATE_INDEXS = {
     "CREATE INDEX IF NOT EXISTS part_mms_id_index ON " + TABLE_NAME + " (" + MMS_ID + ");",
@@ -396,12 +398,7 @@ public class AttachmentDatabase extends Database {
     SQLiteDatabase database = databaseHelper.getWritableDatabase();
     database.delete(TABLE_NAME, null, null);
 
-    File   attachmentsDirectory = context.getDir(DIRECTORY, Context.MODE_PRIVATE);
+    FileUtils.deleteDirectoryContents(context.getDir(DIRECTORY, Context.MODE_PRIVATE));
-    File[] attachments          = attachmentsDirectory.listFiles();
-
-    for (File attachment : attachments) {
-      attachment.delete();
-    }
 
     notifyAttachmentListeners();
   }
@@ -449,11 +446,12 @@ public class AttachmentDatabase extends Database {
   public void insertAttachmentsForPlaceholder(long mmsId, @NonNull AttachmentId attachmentId, @NonNull InputStream inputStream)
       throws MmsException
   {
-    DatabaseAttachment placeholder = getAttachment(attachmentId);
+    DatabaseAttachment placeholder  = getAttachment(attachmentId);
-    SQLiteDatabase     database    = databaseHelper.getWritableDatabase();
+    SQLiteDatabase     database     = databaseHelper.getWritableDatabase();
-    ContentValues      values      = new ContentValues();
+    ContentValues      values       = new ContentValues();
-    DataInfo           oldInfo     = getAttachmentDataFileInfo(attachmentId, DATA);
+    DataInfo           oldInfo      = getAttachmentDataFileInfo(attachmentId, DATA);
-    DataInfo           dataInfo    = setAttachmentData(inputStream, false, attachmentId);
+    DataInfo           dataInfo     = setAttachmentData(inputStream, false, attachmentId);
+    File               transferFile = getTransferFile(databaseHelper.getReadableDatabase(), attachmentId);
 
     if (oldInfo != null) {
       updateAttachmentDataHash(database, oldInfo.hash, dataInfo);
@@ -479,10 +477,16 @@ public class AttachmentDatabase extends Database {
     values.put(DIGEST, (byte[])null);
     values.put(NAME, (String) null);
     values.put(FAST_PREFLIGHT_ID, (String)null);
+    values.put(TRANSFER_FILE, (String)null);
 
     if (database.update(TABLE_NAME, values, PART_ID_WHERE, attachmentId.toStrings()) == 0) {
       //noinspection ResultOfMethodCallIgnored
       dataInfo.file.delete();
+
+      if (transferFile != null) {
+        //noinspection ResultOfMethodCallIgnored
+        transferFile.delete();
+      }
     } else {
       notifyConversationListeners(DatabaseFactory.getMmsDatabase(context).getThreadIdForMessage(mmsId));
       notifyConversationListListeners();
@@ -616,6 +620,38 @@ public class AttachmentDatabase extends Database {
     Log.i(TAG, "[markAttachmentAsTransformed] Updated " + updateCount + " rows.");
   }
 
+  public @NonNull File getOrCreateTransferFile(@NonNull AttachmentId attachmentId) throws IOException {
+    SQLiteDatabase db       = databaseHelper.getWritableDatabase();
+    File           existing = getTransferFile(db, attachmentId);
+
+    if (existing != null) {
+      return existing;
+    }
+
+    File partsDirectory = context.getDir(DIRECTORY, Context.MODE_PRIVATE);
+    File transferFile   = File.createTempFile("transfer", ".mms", partsDirectory);
+
+    ContentValues values = new ContentValues();
+    values.put(TRANSFER_FILE, transferFile.getAbsolutePath());
+
+    db.update(TABLE_NAME, values, PART_ID_WHERE, attachmentId.toStrings());
+
+    return transferFile;
+  }
+
+  private @Nullable static File getTransferFile(@NonNull SQLiteDatabase db, @NonNull AttachmentId attachmentId) {
+    try (Cursor cursor = db.query(TABLE_NAME, new String[] { TRANSFER_FILE }, PART_ID_WHERE, attachmentId.toStrings(), null, null, "1")) {
+      if (cursor != null && cursor.moveToFirst()) {
+        String path = cursor.getString(cursor.getColumnIndexOrThrow(TRANSFER_FILE));
+        if (path != null) {
+          return new File(path);
+        }
+      }
+    }
+
+    return null;
+  }
+
   private static int updateAttachmentAndMatchingHashes(@NonNull SQLiteDatabase database,
                                                        @NonNull AttachmentId attachmentId,
                                                        @Nullable String dataHash,
@@ -1188,6 +1224,7 @@ public class AttachmentDatabase extends Database {
       this.hash   = hash;
     }
   }
+
   public static final class TransformProperties {
 
     @JsonProperty private final boolean skipTransform;

src/org/thoughtcrime/securesms/database/helpers/SQLCipherOpenHelper.java

@@ -98,8 +98,9 @@ public class SQLCipherOpenHelper extends SQLiteOpenHelper {
   private static final int REACTIONS                        = 37;
   private static final int STORAGE_SERVICE                  = 38;
   private static final int REACTIONS_UNREAD_INDEX           = 39;
+  private static final int RESUMABLE_DOWNLOADS              = 40;
 
-  private static final int    DATABASE_VERSION = 39;
+  private static final int    DATABASE_VERSION = 40;
   private static final String DATABASE_NAME    = "signal.db";
 
   private final Context        context;
@@ -679,6 +680,10 @@ public class SQLCipherOpenHelper extends SQLiteOpenHelper {
         db.execSQL("CREATE INDEX IF NOT EXISTS mms_reactions_unread_index ON mms (reactions_unread);");
       }
 
+      if (oldVersion < RESUMABLE_DOWNLOADS) {
+        db.execSQL("ALTER TABLE part ADD COLUMN transfer_file TEXT DEFAULT NULL");
+      }
+
       db.setTransactionSuccessful();
     } finally {
       db.endTransaction();

src/org/thoughtcrime/securesms/jobmanager/JobController.java

@@ -355,6 +355,7 @@ class JobController {
                   .setMaxAttempts(jobSpec.getMaxAttempts())
                   .setQueue(jobSpec.getQueueKey())
                   .setConstraints(Stream.of(constraintSpecs).map(ConstraintSpec::getFactoryKey).toList())
+                  .setMaxBackoff(jobSpec.getMaxBackoff())
                   .build();
   }
 

src/org/thoughtcrime/securesms/jobs/AttachmentDownloadJob.java

@@ -33,6 +33,7 @@ import org.whispersystems.signalservice.api.push.exceptions.PushNetworkException
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.concurrent.TimeUnit;
 
 public class AttachmentDownloadJob extends BaseJob {
 
@@ -55,12 +56,12 @@ public class AttachmentDownloadJob extends BaseJob {
     this(new Job.Parameters.Builder()
                            .setQueue("AttachmentDownloadJob" + attachmentId.getRowId() + "-" + attachmentId.getUniqueId())
                            .addConstraint(NetworkConstraint.KEY)
-                           .setMaxAttempts(25)
+                           .setLifespan(TimeUnit.DAYS.toMillis(1))
+                           .setMaxAttempts(Parameters.UNLIMITED)
                            .build(),
          messageId,
          attachmentId,
          manual);
-
   }
 
   private AttachmentDownloadJob(@NonNull Job.Parameters parameters, long messageId, AttachmentId attachmentId, boolean manual) {
@@ -156,11 +157,9 @@ public class AttachmentDownloadJob extends BaseJob {
   {
 
     AttachmentDatabase database       = DatabaseFactory.getAttachmentDatabase(context);
-    File               attachmentFile = null;
+    File               attachmentFile = database.getOrCreateTransferFile(attachmentId);
 
     try {
-      attachmentFile = createTempFile();
-
       SignalServiceMessageReceiver   messageReceiver = ApplicationDependencies.getSignalServiceMessageReceiver();
       SignalServiceAttachmentPointer pointer         = createAttachmentPointer(attachment);
       InputStream                    stream          = messageReceiver.retrieveAttachment(pointer, attachmentFile, MAX_ATTACHMENT_SIZE, (total, progress) -> EventBus.getDefault().postSticky(new PartProgressEvent(attachment, PartProgressEvent.Type.NETWORK, total, progress)));
@@ -169,18 +168,10 @@ public class AttachmentDownloadJob extends BaseJob {
     } catch (InvalidPartException | NonSuccessfulResponseCodeException | InvalidMessageException | MmsException e) {
       Log.w(TAG, "Experienced exception while trying to download an attachment.", e);
       markFailed(messageId, attachmentId);
-    } finally {
-      if (attachmentFile != null) {
-        //noinspection ResultOfMethodCallIgnored
-        attachmentFile.delete();
-      }
     }
   }
 
-  @VisibleForTesting
+  private SignalServiceAttachmentPointer createAttachmentPointer(Attachment attachment) throws InvalidPartException {
-  SignalServiceAttachmentPointer createAttachmentPointer(Attachment attachment)
-      throws InvalidPartException
-  {
     if (TextUtils.isEmpty(attachment.getLocation())) {
       throw new InvalidPartException("empty content id");
     }

src/org/thoughtcrime/securesms/migrations/CachedAttachmentsMigrationJob.java

@@ -39,12 +39,8 @@ public class CachedAttachmentsMigrationJob extends MigrationJob {
       return;
     }
 
-    try {
+    FileUtils.deleteDirectoryContents(context.getExternalCacheDir());
-      FileUtils.deleteDirectoryContents(context.getExternalCacheDir());
+    GlideApp.get(context).clearDiskCache();
-      GlideApp.get(context).clearDiskCache();
-    } catch (IOException e) {
-      Log.w(TAG, e);
-    }
   }
 
   @Override

src/org/thoughtcrime/securesms/migrations/LegacyMigrationJob.java

@@ -207,20 +207,12 @@ public class LegacyMigrationJob extends MigrationJob {
     }
 
     if (lastSeenVersion < REMOVE_CACHE) {
-      try {
+      FileUtils.deleteDirectoryContents(context.getCacheDir());
-        FileUtils.deleteDirectoryContents(context.getCacheDir());
-      } catch (IOException e) {
-        Log.w(TAG, e);
-      }
     }
 
     if (lastSeenVersion < IMAGE_CACHE_CLEANUP) {
-      try {
+      FileUtils.deleteDirectoryContents(context.getExternalCacheDir());
-        FileUtils.deleteDirectoryContents(context.getExternalCacheDir());
+      GlideApp.get(context).clearDiskCache();
-        GlideApp.get(context).clearDiskCache();
-      } catch (IOException e) {
-        Log.w(TAG, e);
-      }
     }
 
     // This migration became unnecessary after switching away from WorkManager

src/org/thoughtcrime/securesms/util/FileUtils.java

@@ -1,5 +1,7 @@
 package org.thoughtcrime.securesms.util;
 
+import androidx.annotation.Nullable;
+
 import java.io.File;
 import java.io.FileDescriptor;
 import java.io.FileInputStream;
@@ -34,7 +36,7 @@ public final class FileUtils {
     }
   }
 
-  public static void deleteDirectoryContents(File directory) throws IOException {
+  public static void deleteDirectoryContents(@Nullable File directory) {
     if (directory == null || !directory.exists() || !directory.isDirectory()) return;
 
     File[] files = directory.listFiles();
@@ -47,7 +49,7 @@ public final class FileUtils {
     }
   }
 
-  public static void deleteDirectory(File directory) throws IOException {
+  public static void deleteDirectory(@Nullable File directory) {
     if (directory == null || !directory.exists() || !directory.isDirectory()) {
       return;
     }