Add option to trigger sync every hour (fixes #15) (#387)

* AndroidManifest: Add SyncTriggerJobService

* Add Constants#isRunningOnEmulator

* Add Constants: WAIT_FOR_NEXT_SYNC_DELAY_SECS, TRIGGERED_SYNC_DURATION_SECS

* WIP: Schedule Job in BootReceiver

* Add Util/JobUtils

* Util/JobUtils: Improve log text

* Add service/SyncTriggerJobService

scheduled by JobScheduler. See JobUtils#scheduleSyncTriggerServiceJob for more details.

* RunConditionMonitor: Add SyncTriggerReceiver

via LocalBroadcastReceiver.

* BootReceiver: Add ToDo

* Add pref: PREF_RUN_ON_TIME_SCHEDULE

* Fine tune debug constants - time intervals

* JobUtils: In seconds please

* Add strings: en-GB

* RunConditionMonitor: Implement hourly sync time frames (fixes #15)

* Imported translation: de

* Fix lint: .JOB_SCHEDULER_SERVICE, API 21 instead of 23

* JobUtils: Noop on Android API level before 21 (L)

* Fix lint: RequiresApi(21) for SyncTriggerJobService

* Hide pref "run on time schedule" on Android < 5.x

* JobUtils: Show time of grace in brackets when logged

* BootReceiver: Realign comment, remove unnecessary code

app/src/main/AndroidManifest.xml

@@ -147,6 +147,11 @@
                 android:value=".activities.MainActivity" />
         </activity>
         <service android:name=".service.SyncthingService" />
+        <service
+            android:name=".service.SyncTriggerJobService"
+            android:label="SyncTriggerJobService"
+            android:permission="android.permission.BIND_JOB_SERVICE" >
+       </service>
         <receiver android:name=".receiver.BootReceiver">
             <intent-filter>
                 <action android:name="android.intent.action.BOOT_COMPLETED" />

app/src/main/java/com/nutomic/syncthingandroid/activities/SettingsActivity.java

@@ -298,6 +298,11 @@ public class SettingsActivity extends SyncthingActivity {
             );
 
             mCategoryRunConditions = (PreferenceScreen) findPreference("category_run_conditions");
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+                // Remove pref as we use JobScheduler implementation which is not available on API < 21.
+                CheckBoxPreference prefRunOnTimeSchedule = (CheckBoxPreference) findPreference(Constants.PREF_RUN_ON_TIME_SCHEDULE);
+                mCategoryRunConditions.removePreference(prefRunOnTimeSchedule);
+            }
             setPreferenceCategoryChangeListener(mCategoryRunConditions, this::onRunConditionPreferenceChange);
 
             /* Behaviour */

app/src/main/java/com/nutomic/syncthingandroid/receiver/BootReceiver.java

@@ -18,6 +18,10 @@ public class BootReceiver extends BroadcastReceiver {
 
     private static final String TAG = "BootReceiver";
 
+    /**
+     * For testing purposes:
+     * adb root & adb shell am broadcast -a android.intent.action.BOOT_COMPLETED
+     */
     @Override
     public void onReceive(Context context, Intent intent) {
         Boolean bootCompleted = intent.getAction().equals(Intent.ACTION_BOOT_COMPLETED);

app/src/main/java/com/nutomic/syncthingandroid/service/Constants.java

@@ -27,6 +27,7 @@ public class Constants {
     public static final String PREF_RESPECT_BATTERY_SAVING      = "respect_battery_saving";
     public static final String PREF_RESPECT_MASTER_SYNC         = "respect_master_sync";
     public static final String PREF_RUN_IN_FLIGHT_MODE          = "run_in_flight_mode";
+    public static final String PREF_RUN_ON_TIME_SCHEDULE        = "run_on_time_schedule";
 
     // Preferences - Behaviour
     public static final String PREF_USE_ROOT                        = "use_root";
@@ -123,6 +124,13 @@ public class Constants {
                     : 5
     );
 
+    /**
+     * If the user enabled hourly one-time shot sync, the following
+     * parameters are effective.
+     */
+    public static final int WAIT_FOR_NEXT_SYNC_DELAY_SECS       = isRunningOnEmulator() ? 10 : 3600;
+    public static final int TRIGGERED_SYNC_DURATION_SECS        = isRunningOnEmulator() ? 20 : 300;
+
     /**
      * Directory where config is exported to and imported from.
      */

app/src/main/java/com/nutomic/syncthingandroid/service/RunConditionMonitor.java

@@ -19,11 +19,13 @@ import android.os.Handler;
 import android.os.Looper;
 import android.os.PowerManager;
 import android.support.annotation.Nullable;
+import android.support.v4.content.LocalBroadcastManager;
 import android.util.Log;
 
 import com.nutomic.syncthingandroid.R;
 import com.nutomic.syncthingandroid.SyncthingApp;
 import com.nutomic.syncthingandroid.service.ReceiverManager;
+import com.nutomic.syncthingandroid.util.JobUtils;
 
 import java.util.HashSet;
 import java.util.Set;
@@ -41,6 +43,9 @@ public class RunConditionMonitor {
 
     private Boolean ENABLE_VERBOSE_LOG = false;
 
+    public static final String ACTION_SYNC_TRIGGER_FIRED =
+        "com.github.catfriend1.syncthingandroid.service.RunConditionMonitor.ACTION_SYNC_TRIGGER_FIRED";
+
     private static final String POWER_SOURCE_CHARGER_BATTERY = "ac_and_battery_power";
     private static final String POWER_SOURCE_CHARGER = "ac_power";
     private static final String POWER_SOURCE_BATTERY = "battery_power";
@@ -87,9 +92,17 @@ public class RunConditionMonitor {
 
     private final Context mContext;
     private ReceiverManager mReceiverManager;
+    private @Nullable SyncTriggerReceiver mSyncTriggerReceiver = null;
     private Resources res;
     private String mRunDecisionExplanation = "";
 
+    /**
+     * Only relevant if the user has enabled turning Syncthing on by
+     * time schedule for a specific amount of time periodically.
+     * Holds true if we are within a "SyncthingNative should run" time frame.
+     */
+    private Boolean mTimeConditionMatch = false;
+
     @Inject
     SharedPreferences mPreferences;
 
@@ -142,16 +155,31 @@ public class RunConditionMonitor {
         mSyncStatusObserverHandle = ContentResolver.addStatusChangeListener(
                 ContentResolver.SYNC_OBSERVER_TYPE_SETTINGS, mSyncStatusObserver);
 
+        // SyncTriggerReceiver
+        LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(mContext);
+        mSyncTriggerReceiver = new SyncTriggerReceiver();
+        localBroadcastManager.registerReceiver(mSyncTriggerReceiver,
+                new IntentFilter(ACTION_SYNC_TRIGGER_FIRED));
+
         // Initially determine if syncthing should run under current circumstances.
         updateShouldRunDecision();
+
+        // Initially schedule the SyncTrigger job.
+        JobUtils.scheduleSyncTriggerServiceJob(context, Constants.WAIT_FOR_NEXT_SYNC_DELAY_SECS);
     }
 
     public void shutdown() {
         LogV("Shutting down");
+        JobUtils.cancelAllScheduledJobs(mContext);
         if (mSyncStatusObserverHandle != null) {
             ContentResolver.removeStatusChangeListener(mSyncStatusObserverHandle);
             mSyncStatusObserverHandle = null;
         }
+        if (mSyncTriggerReceiver != null) {
+            LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(mContext);
+            localBroadcastManager.unregisterReceiver(mSyncTriggerReceiver);
+            mSyncTriggerReceiver = null;
+        }
         mReceiverManager.unregisterAllReceivers(mContext);
     }
 
@@ -183,6 +211,38 @@ public class RunConditionMonitor {
         }
     }
 
+    private class SyncTriggerReceiver extends BroadcastReceiver {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            LogV("SyncTriggerReceiver: onReceive");
+            boolean prefRunOnTimeSchedule = mPreferences.getBoolean(Constants.PREF_RUN_ON_TIME_SCHEDULE, false);
+            if (!prefRunOnTimeSchedule) {
+                mTimeConditionMatch = false;
+            } else {
+                /**
+                 * Toggle the "digital input" for this condition as the condition change is
+                 * triggered by a time schedule and not the OS notifying us.
+                 */
+                mTimeConditionMatch = !mTimeConditionMatch;
+                updateShouldRunDecision();
+            }
+
+            /**
+             * Reschedule the job.
+             * If we are within a "SyncthingNative should run" time frame,
+             * let the receiver fire and change to "SyncthingNative shouldn't run" after
+             * TRIGGERED_SYNC_DURATION_SECS seconds elapsed.
+             * If we are within a "SyncthingNative shouldn't run" time frame,
+             * let the receiver fire and change to "SyncthingNative should run" after
+             * WAIT_FOR_NEXT_SYNC_DELAY_SECS seconds elapsed.
+             */
+            JobUtils.scheduleSyncTriggerServiceJob(
+                    context,
+                    mTimeConditionMatch ? Constants.TRIGGERED_SYNC_DURATION_SECS : Constants.WAIT_FOR_NEXT_SYNC_DELAY_SECS
+            );
+        }
+    }
+
     /**
      * Event handler that is fired after preconditions changed.
      * We then need to decide if syncthing should run.
@@ -301,6 +361,15 @@ public class RunConditionMonitor {
         boolean prefRespectPowerSaving = mPreferences.getBoolean(Constants.PREF_RESPECT_BATTERY_SAVING, true);
         boolean prefRespectMasterSync = mPreferences.getBoolean(Constants.PREF_RESPECT_MASTER_SYNC, false);
         boolean prefRunInFlightMode = mPreferences.getBoolean(Constants.PREF_RUN_IN_FLIGHT_MODE, false);
+        boolean prefRunOnTimeSchedule = mPreferences.getBoolean(Constants.PREF_RUN_ON_TIME_SCHEDULE, false);
+
+        // PREF_RUN_ON_TIME_SCHEDULE
+        if (prefRunOnTimeSchedule && !mTimeConditionMatch) {
+            // Currently, we aren't within a "SyncthingNative should run" time frame.
+            LogV("decideShouldRun: PREF_RUN_ON_TIME_SCHEDULE && !mTimeConditionMatch");
+            mRunDecisionExplanation = res.getString(R.string.reason_not_within_time_frame);
+            return false;
+        }
 
         // PREF_POWER_SOURCE
         switch (prefPowerSource) {

app/src/main/java/com/nutomic/syncthingandroid/service/SyncTriggerJobService.java

@@ -0,0 +1,37 @@
+package com.nutomic.syncthingandroid.service;
+
+import android.app.job.JobParameters;
+import android.app.job.JobService;
+import android.content.Context;
+import android.content.Intent;
+import android.support.annotation.RequiresApi;
+import android.support.v4.content.LocalBroadcastManager;
+// import android.util.Log;
+
+import com.nutomic.syncthingandroid.service.Constants;
+import com.nutomic.syncthingandroid.service.RunConditionMonitor;
+import com.nutomic.syncthingandroid.util.JobUtils;
+
+/**
+ * SyncTriggerJobService to be scheduled by the JobScheduler.
+ * See {@link JobUtils#scheduleSyncTriggerServiceJob} for more details.
+ */
+@RequiresApi(21)
+public class SyncTriggerJobService extends JobService {
+    private static final String TAG = "SyncTriggerJobService";
+
+    @Override
+    public boolean onStartJob(JobParameters params) {
+        // Log.v(TAG, "onStartJob: Job fired.");
+        Context context = getApplicationContext();
+        LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(context);
+        Intent intent = new Intent(RunConditionMonitor.ACTION_SYNC_TRIGGER_FIRED);
+        localBroadcastManager.sendBroadcast(intent);
+        return true;
+    }
+
+    @Override
+    public boolean onStopJob(JobParameters params) {
+        return true;
+    }
+}

app/src/main/java/com/nutomic/syncthingandroid/util/JobUtils.java

@@ -0,0 +1,49 @@
+package com.nutomic.syncthingandroid.util;
+
+import android.annotation.TargetApi;
+import android.app.job.JobInfo;
+import android.app.job.JobScheduler;
+import android.content.ComponentName;
+import android.content.Context;
+import android.os.Build;
+import android.util.Log;
+
+import com.nutomic.syncthingandroid.service.SyncTriggerJobService;
+
+public class JobUtils {
+
+    private static final String TAG = "JobUtils";
+
+    private static final int TOLERATED_INACCURACY_IN_SECONDS = 120;
+
+    @TargetApi(21)
+    public static void scheduleSyncTriggerServiceJob(Context context, int delayInSeconds) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+            return;
+        }
+        ComponentName serviceComponent = new ComponentName(context, SyncTriggerJobService.class);
+        JobInfo.Builder builder = new JobInfo.Builder(0, serviceComponent);
+
+        // Wait at least "delayInSeconds".
+        builder.setMinimumLatency(delayInSeconds * 1000);
+
+        // Maximum tolerated delay.
+        builder.setOverrideDeadline((delayInSeconds + TOLERATED_INACCURACY_IN_SECONDS) * 1000);
+
+        // Schedule the start of "SyncTriggerJobService" in "X" seconds.
+        JobScheduler jobScheduler = (JobScheduler) context.getSystemService(context.JOB_SCHEDULER_SERVICE);
+        jobScheduler.schedule(builder.build());
+        Log.i(TAG, "Scheduled SyncTriggerJobService to run in " +
+                Integer.toString(delayInSeconds) +
+                "(+" + Integer.toString(TOLERATED_INACCURACY_IN_SECONDS) + ") seconds.");
+    }
+
+    @TargetApi(21)
+    public static void cancelAllScheduledJobs(Context context) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+            return;
+        }
+        JobScheduler jobScheduler = (JobScheduler) context.getSystemService(context.JOB_SCHEDULER_SERVICE);
+        jobScheduler.cancelAll();
+    }
+}

app/src/main/res/values-de/strings.xml

@@ -454,6 +454,9 @@ Bitte melden Sie auftretende Probleme via GitHub.</string>
     <string name="run_in_flight_mode_title">Starte ohne Netzwerkverbindung</string>
     <string name="run_in_flight_mode_summary">Durch Aktivieren der Option wird Syncthing auch dann laufen, wenn Du offline bist. Aktiviere dies, wenn dein Telefon Probleme beim Erkennen von manuell hergestellten WLAN-Verbindungen im Flugmodus hat.</string>
 
+    <string name="run_on_time_schedule_title">Gemäß Zeitplan synchronisieren</string>
+    <string name="run_on_time_schedule_summary">Durch Aktivieren dieser Option wird versucht, stündlich für 5 Minuten zu synchronisieren. Dies kann eine Menge Batterie einsparen, erfordert jedoch, dass Synchronisierungspartner online sind. Hinweis: Dies kann unvollständige temporäre Dateien zurücklassen, bis die nächste geplante Synchronisierung stattfindet und abgeschlossen ist.</string>
+
     <!-- Preferences - Behaviour -->
     <string name="behaviour_autostart_title">Autostart</string>
     <string name="behaviour_autostart_summary">Starte die App automatisch beim Hochfahren.</string>
@@ -760,6 +763,7 @@ Bitte melden Sie auftretende Probleme via GitHub.</string>
     <!-- RunConditionMonitor -->
 
     <!-- Explanations why syncthing is running or not running -->
+    <string name="reason_not_within_time_frame">Sie haben \'Gemäß Zeitplan synchronisieren\' aktiviert, und die letzte Synchronisierung ist nicht länger als eine Stunde her.</string>
     <string name="reason_not_charging">Telefon wird nicht aufgeladen</string>
     <string name="reason_not_on_battery_power">Telefon wird nicht batteriebetrieben</string>
     <string name="reason_not_while_power_saving">Syncthing läuft nicht, weil das Telefon im Energiesparmodus ist.</string>

app/src/main/res/values/strings.xml

@@ -457,6 +457,9 @@ Please report any problems you encounter via Github.</string>
     <string name="run_in_flight_mode_title">Run without network connection</string>
     <string name="run_in_flight_mode_summary">Enabling this option will cause Syncthing to run even when you\'re offline. Enable if your device has problems detecting manual Wi-Fi connections during flight mode.</string>
 
+    <string name="run_on_time_schedule_title">Run according to time schedule</string>
+    <string name="run_on_time_schedule_summary">Enabling this option will attempt to sync every hour for the duration of 5 minutes. This can save a lot of battery but requires sync partners to be online. Please note: This may leave incomplete temporary files behind until the next scheduled sync takes place.</string>
+
     <!-- Preferences - Behaviour -->
     <string name="behaviour_autostart_title">Autostart</string>
     <string name="behaviour_autostart_summary">Start app automatically on operating system startup.</string>
@@ -781,6 +784,7 @@ Please report any problems you encounter via Github.</string>
     <!-- RunConditionMonitor -->
 
     <!-- Explanations why syncthing is running or not running -->
+    <string name="reason_not_within_time_frame">You enabled \'Run according to time schedule\' and the last sync was no more than an hour ago.</string>
     <string name="reason_not_charging">Phone is not charging.</string>
     <string name="reason_not_on_battery_power">Phone is not running on battery power.</string>
     <string name="reason_not_while_power_saving">Syncthing is not running as the phone is currently power saving.</string>

app/src/main/res/xml/app_settings.xml

@@ -72,6 +72,13 @@
             android:summary="@string/run_in_flight_mode_summary"
             android:defaultValue="false" />
 
+        <!-- Run on time schedule -->
+        <CheckBoxPreference
+            android:key="run_on_time_schedule"
+            android:title="@string/run_on_time_schedule_title"
+            android:summary="@string/run_on_time_schedule_summary"
+            android:defaultValue="false" />
+
     </PreferenceScreen>
 
     <PreferenceScreen