add ability to cancel in-progress one-off backup

src/main/AndroidManifest.xml

@@ -143,7 +143,11 @@
         </service>
 
         <receiver
-            android:name=".services.EventReceiver"
+            android:name=".receiver.WorkManagerEventReceiver"
+            android:exported="false" />
+
+        <receiver
+            android:name=".receiver.SystemEventReceiver"
             android:exported="false">
             <intent-filter>
                 <action android:name="android.intent.action.BOOT_COMPLETED" />
@@ -157,7 +161,7 @@
         </receiver>
 
         <receiver
-            android:name=".services.UnifiedPushDistributor"
+            android:name=".receiver.UnifiedPushDistributor"
             android:enabled="false"
             android:exported="true">
             <intent-filter>

src/main/java/eu/siacs/conversations/receiver/SystemEventReceiver.java

@@ -1,4 +1,4 @@
-package eu.siacs.conversations.services;
+package eu.siacs.conversations.receiver;
 
 import android.content.BroadcastReceiver;
 import android.content.Context;
@@ -10,9 +10,10 @@ import android.util.Log;
 import com.google.common.base.Strings;
 
 import eu.siacs.conversations.Config;
+import eu.siacs.conversations.services.XmppConnectionService;
 import eu.siacs.conversations.utils.Compatibility;
 
-public class EventReceiver extends BroadcastReceiver {
+public class SystemEventReceiver extends BroadcastReceiver {
 
     public static final String SETTING_ENABLED_ACCOUNTS = "enabled_accounts";
     public static final String EXTRA_NEEDS_FOREGROUND_SERVICE = "needs_foreground_service";

src/main/java/eu/siacs/conversations/receiver/UnifiedPushDistributor.java

@@ -1,4 +1,4 @@
-package eu.siacs.conversations.services;
+package eu.siacs.conversations.receiver;
 
 import android.app.PendingIntent;
 import android.content.BroadcastReceiver;
@@ -25,6 +25,7 @@ import java.util.List;
 
 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.persistance.UnifiedPushDatabase;
+import eu.siacs.conversations.services.XmppConnectionService;
 import eu.siacs.conversations.utils.Compatibility;
 
 public class UnifiedPushDistributor extends BroadcastReceiver {

src/main/java/eu/siacs/conversations/receiver/WorkManagerEventReceiver.java

@@ -0,0 +1,32 @@
+package eu.siacs.conversations.receiver;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.util.Log;
+
+import androidx.work.WorkManager;
+
+import com.google.common.base.Strings;
+
+import eu.siacs.conversations.Config;
+import eu.siacs.conversations.ui.fragment.settings.BackupSettingsFragment;
+
+public class WorkManagerEventReceiver extends BroadcastReceiver {
+
+    public static final String ACTION_STOP_BACKUP = "eu.siacs.conversations.receiver.STOP_BACKUP";
+
+    @Override
+    public void onReceive(final Context context, final Intent intent) {
+        final var action = Strings.nullToEmpty(intent == null ? null : intent.getAction());
+        if (action.equals(ACTION_STOP_BACKUP)) {
+            stopBackup(context);
+        }
+    }
+
+    private void stopBackup(final Context context) {
+        Log.d(Config.LOGTAG, "trying to stop one-off backup worker");
+        final var workManager = WorkManager.getInstance(context);
+        workManager.cancelUniqueWork(BackupSettingsFragment.CREATE_ONE_OFF_BACKUP);
+    }
+}

src/main/java/eu/siacs/conversations/services/ContactChooserTargetService.java

@@ -21,6 +21,7 @@ import java.util.List;
 
 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.entities.Conversation;
+import eu.siacs.conversations.receiver.SystemEventReceiver;
 import eu.siacs.conversations.ui.ConversationsActivity;
 import eu.siacs.conversations.utils.Compatibility;
 
@@ -44,7 +45,7 @@ public class ContactChooserTargetService extends ChooserTargetService implements
     @Override
     public List<ChooserTarget> onGetChooserTargets(
             final ComponentName targetActivityName, final IntentFilter matchedFilter) {
-        if (!EventReceiver.hasEnabledAccounts(this)) {
+        if (!SystemEventReceiver.hasEnabledAccounts(this)) {
             return Collections.emptyList();
         }
         final Intent intent = new Intent(this, XmppConnectionService.class);

src/main/java/eu/siacs/conversations/services/UnifiedPushBroker.java

@@ -28,6 +28,7 @@ import eu.siacs.conversations.R;
 import eu.siacs.conversations.entities.Account;
 import eu.siacs.conversations.parser.AbstractParser;
 import eu.siacs.conversations.persistance.UnifiedPushDatabase;
+import eu.siacs.conversations.receiver.UnifiedPushDistributor;
 import eu.siacs.conversations.xml.Element;
 import eu.siacs.conversations.xml.Namespace;
 import eu.siacs.conversations.xmpp.Jid;

src/main/java/eu/siacs/conversations/services/XmppConnectionService.java

@@ -128,6 +128,7 @@ import eu.siacs.conversations.parser.PresenceParser;
 import eu.siacs.conversations.persistance.DatabaseBackend;
 import eu.siacs.conversations.persistance.FileBackend;
 import eu.siacs.conversations.persistance.UnifiedPushDatabase;
+import eu.siacs.conversations.receiver.SystemEventReceiver;
 import eu.siacs.conversations.ui.ChooseAccountForProfilePictureActivity;
 import eu.siacs.conversations.ui.ConversationsActivity;
 import eu.siacs.conversations.ui.RtpSessionActivity;
@@ -678,7 +679,7 @@ public class XmppConnectionService extends Service {
     @Override
     public int onStartCommand(final Intent intent, int flags, int startId) {
         final String action = Strings.nullToEmpty(intent == null ? null : intent.getAction());
-        final boolean needsForegroundService = intent != null && intent.getBooleanExtra(EventReceiver.EXTRA_NEEDS_FOREGROUND_SERVICE, false);
+        final boolean needsForegroundService = intent != null && intent.getBooleanExtra(SystemEventReceiver.EXTRA_NEEDS_FOREGROUND_SERVICE, false);
         if (needsForegroundService) {
             Log.d(Config.LOGTAG, "toggle forced foreground service after receiving event (action=" + action + ")");
             toggleForegroundService(true);
@@ -1286,7 +1287,7 @@ public class XmppConnectionService extends Service {
         this.accounts = databaseBackend.getAccounts();
         final SharedPreferences.Editor editor = getPreferences().edit();
         final boolean hasEnabledAccounts = hasEnabledAccounts();
-        editor.putBoolean(EventReceiver.SETTING_ENABLED_ACCOUNTS, hasEnabledAccounts).apply();
+        editor.putBoolean(SystemEventReceiver.SETTING_ENABLED_ACCOUNTS, hasEnabledAccounts).apply();
         editor.apply();
         toggleSetProfilePictureActivity(hasEnabledAccounts);
         reconfigurePushDistributor();
@@ -1582,7 +1583,7 @@ public class XmppConnectionService extends Service {
             return;
         }
         final long triggerAtMillis = SystemClock.elapsedRealtime() + (Config.POST_CONNECTIVITY_CHANGE_PING_INTERVAL * 1000);
-        final Intent intent = new Intent(this, EventReceiver.class);
+        final Intent intent = new Intent(this, SystemEventReceiver.class);
         intent.setAction(ACTION_POST_CONNECTIVITY_CHANGE);
         try {
             final PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 1, intent, s()
@@ -1604,7 +1605,7 @@ public class XmppConnectionService extends Service {
         if (alarmManager == null) {
             return;
         }
-        final Intent intent = new Intent(this, EventReceiver.class);
+        final Intent intent = new Intent(this, SystemEventReceiver.class);
         intent.setAction(ACTION_PING);
         try {
             final PendingIntent pendingIntent =
@@ -1623,7 +1624,7 @@ public class XmppConnectionService extends Service {
         if (alarmManager == null) {
             return;
         }
-        final Intent intent = new Intent(this, EventReceiver.class);
+        final Intent intent = new Intent(this, SystemEventReceiver.class);
         intent.setAction(ACTION_IDLE_PING);
         try {
             final PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, intent, s()
@@ -2573,7 +2574,7 @@ public class XmppConnectionService extends Service {
 
     private void syncEnabledAccountSetting() {
         final boolean hasEnabledAccounts = hasEnabledAccounts();
-        getPreferences().edit().putBoolean(EventReceiver.SETTING_ENABLED_ACCOUNTS, hasEnabledAccounts).apply();
+        getPreferences().edit().putBoolean(SystemEventReceiver.SETTING_ENABLED_ACCOUNTS, hasEnabledAccounts).apply();
         toggleSetProfilePictureActivity(hasEnabledAccounts);
     }
 

src/main/java/eu/siacs/conversations/ui/fragment/settings/BackupSettingsFragment.java

@@ -36,7 +36,7 @@ import java.util.concurrent.TimeUnit;
 
 public class BackupSettingsFragment extends XmppPreferenceFragment {
 
-    private static final String CREATE_ONE_OFF_BACKUP = "create_one_off_backup";
+    public static final String CREATE_ONE_OFF_BACKUP = "create_one_off_backup";
     private static final String RECURRING_BACKUP = "recurring_backup";
 
     private final ActivityResultLauncher<String> requestStorageForBackupLauncher =

src/main/java/eu/siacs/conversations/ui/fragment/settings/UpSettingsFragment.java

@@ -13,7 +13,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 
 import eu.siacs.conversations.R;
-import eu.siacs.conversations.services.UnifiedPushDistributor;
+import eu.siacs.conversations.receiver.UnifiedPushDistributor;
 import eu.siacs.conversations.xmpp.Jid;
 
 import java.net.URI;

src/main/java/eu/siacs/conversations/utils/Compatibility.java

@@ -1,6 +1,6 @@
 package eu.siacs.conversations.utils;
 
-import static eu.siacs.conversations.services.EventReceiver.EXTRA_NEEDS_FOREGROUND_SERVICE;
+import static eu.siacs.conversations.receiver.SystemEventReceiver.EXTRA_NEEDS_FOREGROUND_SERVICE;
 
 import android.annotation.SuppressLint;
 import android.app.ActivityOptions;

src/main/java/eu/siacs/conversations/worker/ExportBackupWorker.java

@@ -11,6 +11,7 @@ import android.content.pm.ServiceInfo;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.net.Uri;
+import android.os.SystemClock;
 import android.util.Log;
 
 import androidx.annotation.NonNull;
@@ -21,6 +22,7 @@ import androidx.work.WorkerParameters;
 
 import com.google.common.base.Optional;
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
 import com.google.gson.stream.JsonWriter;
 
 import eu.siacs.conversations.Config;
@@ -31,6 +33,7 @@ import eu.siacs.conversations.entities.Conversation;
 import eu.siacs.conversations.entities.Message;
 import eu.siacs.conversations.persistance.DatabaseBackend;
 import eu.siacs.conversations.persistance.FileBackend;
+import eu.siacs.conversations.receiver.WorkManagerEventReceiver;
 import eu.siacs.conversations.utils.BackupFileHeader;
 import eu.siacs.conversations.utils.Compatibility;
 
@@ -65,7 +68,7 @@ import javax.crypto.spec.SecretKeySpec;
 public class ExportBackupWorker extends Worker {
 
     private static final SimpleDateFormat DATE_FORMAT =
-            new SimpleDateFormat("yyyy-MM-dd", Locale.US);
+            new SimpleDateFormat("yyyy-MM-dd-HH-mm", Locale.US);
 
     public static final String KEYTYPE = "AES";
     public static final String CIPHERMODE = "AES/GCM/NoPadding";
@@ -76,6 +79,11 @@ public class ExportBackupWorker extends Worker {
     private static final int NOTIFICATION_ID = 19;
     private static final int BACKUP_CREATED_NOTIFICATION_ID = 23;
 
+    private static final int PENDING_INTENT_FLAGS =
+            s()
+                    ? PendingIntent.FLAG_IMMUTABLE | PendingIntent.FLAG_UPDATE_CURRENT
+                    : PendingIntent.FLAG_UPDATE_CURRENT;
+
     private final boolean recurringBackup;
 
     public ExportBackupWorker(@NonNull Context context, @NonNull WorkerParameters workerParams) {
@@ -99,9 +107,12 @@ public class ExportBackupWorker extends Worker {
                 | NoSuchProviderException e) {
             Log.d(Config.LOGTAG, "could not create backup", e);
             return Result.failure();
+        } finally {
+            getApplicationContext()
+                    .getSystemService(NotificationManager.class)
+                    .cancel(NOTIFICATION_ID);
         }
         Log.d(Config.LOGTAG, "done creating " + files.size() + " backup files");
-        getApplicationContext().getSystemService(NotificationManager.class).cancel(NOTIFICATION_ID);
         if (files.isEmpty() || recurringBackup) {
             return Result.success();
         }
@@ -113,13 +124,7 @@ public class ExportBackupWorker extends Worker {
     @Override
     public ForegroundInfo getForegroundInfo() {
         Log.d(Config.LOGTAG, "getForegroundInfo()");
-        final var context = getApplicationContext();
+        final NotificationCompat.Builder notification = getNotification();
-        final NotificationCompat.Builder notification =
-                new NotificationCompat.Builder(context, "backup");
-        notification
-                .setContentTitle(context.getString(R.string.notification_create_backup_title))
-                .setSmallIcon(R.drawable.ic_archive_24dp)
-                .setProgress(1, 0, false);
         if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {
             return new ForegroundInfo(
                     NOTIFICATION_ID,
@@ -144,10 +149,13 @@ public class ExportBackupWorker extends Worker {
 
         int count = 0;
         final int max = accounts.size();
-        final SecureRandom secureRandom = new SecureRandom();
+        final ImmutableList.Builder<File> files = new ImmutableList.Builder<>();
-        final List<File> files = new ArrayList<>();
         Log.d(Config.LOGTAG, "starting backup for " + max + " accounts");
         for (final Account account : accounts) {
+            if (isStopped()) {
+                Log.d(Config.LOGTAG, "ExportBackupWorker has stopped. Returning what we have");
+                return files.build();
+            }
             final String password = account.getPassword();
             if (Strings.nullToEmpty(password).trim().isEmpty()) {
                 Log.d(
@@ -155,84 +163,140 @@ public class ExportBackupWorker extends Worker {
                         String.format(
                                 "skipping backup for %s because password is empty. unable to encrypt",
                                 account.getJid().asBareJid()));
+                count++;
                 continue;
             }
-            Log.d(
-                    Config.LOGTAG,
-                    String.format(
-                            "exporting data for account %s (%s)",
-                            account.getJid().asBareJid(), account.getUuid()));
-            final byte[] IV = new byte[12];
-            final byte[] salt = new byte[16];
-            secureRandom.nextBytes(IV);
-            secureRandom.nextBytes(salt);
-            final BackupFileHeader backupFileHeader =
-                    new BackupFileHeader(
-                            context.getString(R.string.app_name),
-                            account.getJid(),
-                            System.currentTimeMillis(),
-                            IV,
-                            salt);
-            final NotificationCompat.Builder notification =
-                    new NotificationCompat.Builder(context, "backup");
-            notification
-                    .setContentTitle(context.getString(R.string.notification_create_backup_title))
-                    .setSmallIcon(R.drawable.ic_archive_24dp)
-                    .setProgress(1, 0, false);
-            final Progress progress = new Progress(notification, max, count);
             final String filename =
                     String.format(
                             "%s.%s.ceb",
                             account.getJid().asBareJid().toEscapedString(),
                             DATE_FORMAT.format(new Date()));
             final File file = new File(FileBackend.getBackupDirectory(context), filename);
+            try {
+                export(database, account, password, file, max, count);
+            } catch (final WorkStoppedException e) {
+                if (file.delete()) {
+                    Log.d(
+                            Config.LOGTAG,
+                            "deleted in progress backup file " + file.getAbsolutePath());
+                }
+                Log.d(Config.LOGTAG, "ExportBackupWorker has stopped. Returning what we have");
+                return files.build();
+            }
             files.add(file);
-            final File directory = file.getParentFile();
-            if (directory != null && directory.mkdirs()) {
-                Log.d(Config.LOGTAG, "created backup directory " + directory.getAbsolutePath());
-            }
-            final FileOutputStream fileOutputStream = new FileOutputStream(file);
-            final DataOutputStream dataOutputStream = new DataOutputStream(fileOutputStream);
-            backupFileHeader.write(dataOutputStream);
-            dataOutputStream.flush();
-
-            final Cipher cipher =
-                    Compatibility.twentyEight()
-                            ? Cipher.getInstance(CIPHERMODE)
-                            : Cipher.getInstance(CIPHERMODE, PROVIDER);
-            final byte[] key = getKey(password, salt);
-            SecretKeySpec keySpec = new SecretKeySpec(key, KEYTYPE);
-            IvParameterSpec ivSpec = new IvParameterSpec(IV);
-            cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
-            CipherOutputStream cipherOutputStream =
-                    new CipherOutputStream(fileOutputStream, cipher);
-
-            final GZIPOutputStream gzipOutputStream = new GZIPOutputStream(cipherOutputStream);
-            final JsonWriter jsonWriter =
-                    new JsonWriter(
-                            new OutputStreamWriter(gzipOutputStream, StandardCharsets.UTF_8));
-            jsonWriter.beginArray();
-            final SQLiteDatabase db = database.getReadableDatabase();
-            final String uuid = account.getUuid();
-            accountExport(db, uuid, jsonWriter);
-            simpleExport(db, Conversation.TABLENAME, Conversation.ACCOUNT, uuid, jsonWriter);
-            messageExport(db, uuid, jsonWriter, progress);
-            for (final String table :
-                    Arrays.asList(
-                            SQLiteAxolotlStore.PREKEY_TABLENAME,
-                            SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
-                            SQLiteAxolotlStore.SESSION_TABLENAME,
-                            SQLiteAxolotlStore.IDENTITIES_TABLENAME)) {
-                simpleExport(db, table, SQLiteAxolotlStore.ACCOUNT, uuid, jsonWriter);
-            }
-            jsonWriter.endArray();
-            jsonWriter.flush();
-            jsonWriter.close();
-            mediaScannerScanFile(file);
-            Log.d(Config.LOGTAG, "written backup to " + file.getAbsoluteFile());
             count++;
         }
-        return files;
+        return files.build();
+    }
+
+    private void export(
+            final DatabaseBackend database,
+            final Account account,
+            final String password,
+            final File file,
+            final int max,
+            final int count)
+            throws IOException,
+                    InvalidKeySpecException,
+                    InvalidAlgorithmParameterException,
+                    InvalidKeyException,
+                    NoSuchPaddingException,
+                    NoSuchAlgorithmException,
+                    NoSuchProviderException,
+                    WorkStoppedException {
+        final var context = getApplicationContext();
+        final SecureRandom secureRandom = new SecureRandom();
+        Log.d(
+                Config.LOGTAG,
+                String.format(
+                        "exporting data for account %s (%s)",
+                        account.getJid().asBareJid(), account.getUuid()));
+        final byte[] IV = new byte[12];
+        final byte[] salt = new byte[16];
+        secureRandom.nextBytes(IV);
+        secureRandom.nextBytes(salt);
+        final BackupFileHeader backupFileHeader =
+                new BackupFileHeader(
+                        context.getString(R.string.app_name),
+                        account.getJid(),
+                        System.currentTimeMillis(),
+                        IV,
+                        salt);
+        final var notification = getNotification();
+        if (!recurringBackup) {
+            final var cancel = new Intent(context, WorkManagerEventReceiver.class);
+            cancel.setAction(WorkManagerEventReceiver.ACTION_STOP_BACKUP);
+            final var cancelPendingIntent =
+                    PendingIntent.getBroadcast(context, 197, cancel, PENDING_INTENT_FLAGS);
+            notification.addAction(
+                    new NotificationCompat.Action.Builder(
+                                    R.drawable.ic_cancel_24dp,
+                                    context.getString(R.string.cancel),
+                                    cancelPendingIntent)
+                            .build());
+        }
+        final Progress progress = new Progress(notification, max, count);
+        final File directory = file.getParentFile();
+        if (directory != null && directory.mkdirs()) {
+            Log.d(Config.LOGTAG, "created backup directory " + directory.getAbsolutePath());
+        }
+        final FileOutputStream fileOutputStream = new FileOutputStream(file);
+        final DataOutputStream dataOutputStream = new DataOutputStream(fileOutputStream);
+        backupFileHeader.write(dataOutputStream);
+        dataOutputStream.flush();
+
+        final Cipher cipher =
+                Compatibility.twentyEight()
+                        ? Cipher.getInstance(CIPHERMODE)
+                        : Cipher.getInstance(CIPHERMODE, PROVIDER);
+        final byte[] key = getKey(password, salt);
+        SecretKeySpec keySpec = new SecretKeySpec(key, KEYTYPE);
+        IvParameterSpec ivSpec = new IvParameterSpec(IV);
+        cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
+        CipherOutputStream cipherOutputStream = new CipherOutputStream(fileOutputStream, cipher);
+
+        final GZIPOutputStream gzipOutputStream = new GZIPOutputStream(cipherOutputStream);
+        final JsonWriter jsonWriter =
+                new JsonWriter(new OutputStreamWriter(gzipOutputStream, StandardCharsets.UTF_8));
+        jsonWriter.beginArray();
+        final SQLiteDatabase db = database.getReadableDatabase();
+        final String uuid = account.getUuid();
+        accountExport(db, uuid, jsonWriter);
+        simpleExport(db, Conversation.TABLENAME, Conversation.ACCOUNT, uuid, jsonWriter);
+        messageExport(db, uuid, jsonWriter, progress);
+        for (final String table :
+                Arrays.asList(
+                        SQLiteAxolotlStore.PREKEY_TABLENAME,
+                        SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
+                        SQLiteAxolotlStore.SESSION_TABLENAME,
+                        SQLiteAxolotlStore.IDENTITIES_TABLENAME)) {
+            throwIfWorkStopped();
+            simpleExport(db, table, SQLiteAxolotlStore.ACCOUNT, uuid, jsonWriter);
+        }
+        jsonWriter.endArray();
+        jsonWriter.flush();
+        jsonWriter.close();
+        mediaScannerScanFile(file);
+        Log.d(Config.LOGTAG, "written backup to " + file.getAbsoluteFile());
+    }
+
+    private NotificationCompat.Builder getNotification() {
+        final var context = getApplicationContext();
+        final NotificationCompat.Builder notification =
+                new NotificationCompat.Builder(context, "backup");
+        notification
+                .setContentTitle(context.getString(R.string.notification_create_backup_title))
+                .setSmallIcon(R.drawable.ic_archive_24dp)
+                .setProgress(1, 0, false);
+        notification.setOngoing(true);
+        notification.setLocalOnly(true);
+        return notification;
+    }
+
+    private void throwIfWorkStopped() throws WorkStoppedException {
+        if (isStopped()) {
+            throw new WorkStoppedException();
+        }
     }
 
     private void mediaScannerScanFile(final File file) {
@@ -313,7 +377,7 @@ public class ExportBackupWorker extends Worker {
             final String uuid,
             final JsonWriter writer,
             final Progress progress)
-            throws IOException {
+            throws IOException, WorkStoppedException {
         final var notificationManager =
                 getApplicationContext().getSystemService(NotificationManager.class);
         try (final Cursor cursor =
@@ -322,9 +386,11 @@ public class ExportBackupWorker extends Worker {
                         new String[] {uuid})) {
             final int size = cursor != null ? cursor.getCount() : 0;
             Log.d(Config.LOGTAG, "exporting " + size + " messages for account " + uuid);
+            long lastUpdate = 0;
             int i = 0;
-            int p = 0;
+            int p = Integer.MIN_VALUE;
             while (cursor != null && cursor.moveToNext()) {
+                throwIfWorkStopped();
                 writer.beginObject();
                 writer.name("table");
                 writer.value(Message.TABLENAME);
@@ -339,8 +405,9 @@ public class ExportBackupWorker extends Worker {
                 writer.endObject();
                 writer.endObject();
                 final int percentage = i * 100 / size;
-                if (p < percentage) {
+                if (p < percentage && (SystemClock.elapsedRealtime() - lastUpdate) > 2_000) {
                     p = percentage;
+                    lastUpdate = SystemClock.elapsedRealtime();
                     notificationManager.notify(NOTIFICATION_ID, progress.build(p));
                 }
                 i++;
@@ -377,13 +444,7 @@ public class ExportBackupWorker extends Worker {
         final Intent chooser =
                 Intent.createChooser(intent, context.getString(R.string.share_backup_files));
         final var shareFilesIntent =
-                PendingIntent.getActivity(
+                PendingIntent.getActivity(context, 190, chooser, PENDING_INTENT_FLAGS);
-                        context,
-                        190,
-                        chooser,
-                        s()
-                                ? PendingIntent.FLAG_IMMUTABLE | PendingIntent.FLAG_UPDATE_CURRENT
-                                : PendingIntent.FLAG_UPDATE_CURRENT);
 
         NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(context, "backup");
         mBuilder.setContentTitle(context.getString(R.string.notification_backup_created_title))
@@ -418,14 +479,7 @@ public class ExportBackupWorker extends Worker {
         for (final Intent intent : getPossibleFileOpenIntents(context, path)) {
             if (intent.resolveActivityInfo(context.getPackageManager(), 0) != null) {
                 return Optional.of(
-                        PendingIntent.getActivity(
+                        PendingIntent.getActivity(context, 189, intent, PENDING_INTENT_FLAGS));
-                                context,
-                                189,
-                                intent,
-                                s()
-                                        ? PendingIntent.FLAG_IMMUTABLE
-                                                | PendingIntent.FLAG_UPDATE_CURRENT
-                                        : PendingIntent.FLAG_UPDATE_CURRENT));
             }
         }
         return Optional.absent();
@@ -474,4 +528,6 @@ public class ExportBackupWorker extends Worker {
             return notification.build();
         }
     }
+
+    private static class WorkStoppedException extends Exception {}
 }