Scheduling background job on Android at the right time (old)

Better version can be found here: https://speakerdeck.com/vrallev/scheduling-background-job-on-android-at-the-right-time-1

Transcript

1. Schedule background jobs at the right time Ralf Wondratschek 2016-10-23
5. Motivation
6. Motivation • Every app has some kind of repeated work • Don’t waste battery unnecessarily • App should still work correctly even in Doze mode or in App Standby • Scheduling repeated work is quite a headache with 3 different APIs all doing similar things
7. Doze & App Standby
8. https://developer.android.com/images/training/doze.png
9. All APIs in a nutshell
10. AlarmManager https://plus.google.com/+AndroidDevelopers/posts/GdNrQciPwqo
11. AlarmManager + Available on all devices + Easy to send broadcast to start a service delayed - API behavior differs between platform versions - A lot of boilerplate - Device state ignored - …
12. JobScheduler + Easy to use with fluent API + Respects device state - Only on API 21+ (some features only API 24+) - Platform bugs - Still a lot of boilerplate code
13. GCM Network Manager + Similar API like JobScheduler + minSdkVersion 9 - Part of Google’s Play Services SDK - Can’t be used without Play Services being pre-installed (most Chinese devices) - API contains some gotchas
14. (Firebase JobDispatcher) + Wrapper for job scheduling engines - Setup is difficult - Library not maintained - Only GCM NetworkManager supported - Many open issues → I would not recommend using it
15. Demo - Reminder app https://github.com/vRallev/job-sample
16. Requirements • Show the reminder in a notification • Sync reminders with the server • Support all devices • Be a good citizen
17. Reminder job • Must be exact • Can have multiple at the same time • AlarmManager is the correct API
18. Reminder job <receiver android:name=".reminder.ReminderReceiver" android:exported="false"/> public class ReminderReceiver extends BroadcastReceiver { private static final String EXTRA_ID = "EXTRA_ID"; @Override public void onReceive(Context context, Intent intent) { int id = intent.getIntExtra(EXTRA_ID, -1); if (id < 0) { return; } Reminder reminder = ReminderEngine.instance().getReminderById(id); if (reminder != null) { ReminderEngine.instance().showReminder(reminder); } } }
19. API 14-18 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
20. API 14-18 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
21. API 19-22 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.set(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
22. API 19-22 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.setExact(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
23. API 23-24 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.setExact(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
24. API 23-24 public static void schedule(Context context, Reminder reminder) { Intent intent = new Intent(context, ReminderReceiver.class); intent.putExtra(EXTRA_ID, reminder.getId()); int requestCode = reminder.getId(); int flags = PendingIntent.FLAG_UPDATE_CURRENT | PendingIntent.FLAG_ONE_SHOT; PendingIntent pendingIntent = PendingIntent .getBroadcast(context, requestCode, intent, flags); AlarmManager manager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, reminder.getTimestamp(), pendingIntent); }
25. Reminder job public static void schedule(Context context, Reminder reminder) { // … if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { manager.setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, when, pendingIntent); } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) { manager.setExact(AlarmManager.RTC_WAKEUP, when, pendingIntent); } else { manager.set(AlarmManager.RTC_WAKEUP, when, pendingIntent); } }
26. Sync job • Can be inexact, but must be repeating • Run job only on an unmetered network and only if device is charging • Don’t wake up the device to sync data • JobScheduler and GCM Network Manager work best, AlarmManager is fallback
27. API 21-23 <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/> <application … > <service android:name=".sync.SyncJob" android:permission="android.permission.BIND_JOB_SERVICE"/> </application>
28. public class SyncJob extends JobService { @Override public boolean onStartJob(JobParameters params) { // called on main thread new Thread(() -> { try { new SyncEngine().syncReminders(); } catch (IOException e) { e.printStackTrace(); } finally { jobFinished(params, false); // don't forget to call } }).start(); return true; // we have background work } @Override public boolean onStopJob(JobParameters params) { return false; // don't reschedule } } API 21-23
29. private static final int JOB_ID = 1; public static void schedule(Context context) { long interval = TimeUnit.HOURS.toMillis(6); JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class)) .setRequiresCharging(true) .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED) .setPersisted(true) .setPeriodic(interval) .build(); JobScheduler jobScheduler = (JobScheduler) context .getSystemService(Context.JOB_SCHEDULER_SERVICE); jobScheduler.schedule(jobInfo); } API 21-23
30. private static final int JOB_ID = 1; public static void schedule(Context context) { long interval = TimeUnit.HOURS.toMillis(6); JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class)) .setRequiresCharging(true) .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED) .setPersisted(true) .setPeriodic(interval) .build(); JobScheduler jobScheduler = (JobScheduler) context .getSystemService(Context.JOB_SCHEDULER_SERVICE); jobScheduler.schedule(jobInfo); } API 21-23
31. private static final int JOB_ID = 1; public static void schedule(Context context) { long interval = TimeUnit.HOURS.toMillis(6); long flex = TimeUnit.HOURS.toMillis(3); JobInfo jobInfo = new JobInfo.Builder(JOB_ID, new ComponentName(context, SyncJob.class)) .setRequiresCharging(true) .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED) .setPersisted(true) .setPeriodic(interval, flex) .build(); JobScheduler jobScheduler = (JobScheduler) context .getSystemService(Context.JOB_SCHEDULER_SERVICE); jobScheduler.schedule(jobInfo); } API 24
32. <service android:name=".sync.SyncJob" android:exported="true" android:permission="com.google.android.gms.permission.BIND_NETWORK_TASK_SERVICE"> <intent-filter> <action android:name="com.google.android.gms.gcm.ACTION_TASK_READY"/> </intent-filter> </service> With Google Play Services
33. public class SyncJob extends GcmTaskService { @Override public int onRunTask(TaskParams taskParams) { try { new SyncEngine().syncReminders(); return GcmNetworkManager.RESULT_SUCCESS; } catch (IOException e) { e.printStackTrace(); return GcmNetworkManager.RESULT_FAILURE; } } } With Google Play Services
34. private static final String TAG = "SyncJob"; public void schedule(Context context) { long interval = TimeUnit.HOURS.toMillis(6); long flex = TimeUnit.HOURS.toMillis(3); PeriodicTask task = new PeriodicTask.Builder() .setTag(TAG) .setService(SyncJob.class) .setRequiresCharging(true) .setRequiredNetwork(Task.NETWORK_STATE_UNMETERED) .setPersisted(true) .setUpdateCurrent(true) .setPeriod(interval / 1_000) .setFlex(flex / 1_000) .build(); GcmNetworkManager.getInstance(context).schedule(task); } With Google Play Services
35. private static final String TAG = "SyncJob"; public void schedule(Context context) { long interval = TimeUnit.HOURS.toMillis(6); long flex = TimeUnit.HOURS.toMillis(3); PeriodicTask task = new PeriodicTask.Builder() .setTag(TAG) .setService(SyncJob.class) .setRequiresCharging(true) .setRequiredNetwork(Task.NETWORK_STATE_UNMETERED) .setPersisted(true) .setUpdateCurrent(true) .setPeriod(interval / 1_000) .setFlex(flex / 1_000) .build(); GcmNetworkManager.getInstance(context).schedule(task); } With Google Play Services
36. API 14-19 • Use AlarmManager • As much fun as the reminder job…
37. Sync job public void schedule(Context context) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) { scheduleWithJobScheduler24(context); } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { scheduleWithJobScheduler21(context); } else if (GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context) == ConnectionResult.SUCCESS) { scheduleWithGcmNetworkManager(context); } else { scheduleWithAlarmManager(context); } }
38. Conclusion • A lot of boilerplate to achieve something that should be simple
39. Conclusion • A lot of boilerplate to achieve something that should be simple • It should be much easier
40. android-job Fork me on GitHub github.com/evernote/
41. android-job • Single API to use the JobSchduler, GCM Network Manager and AlarmManager • All API 24 features supported • Automatically chooses best API to run a job • Less boilerplate, e.g. no manifest entry needed • No reflection used • Maintained and improved continuously • … and more
42. Setup dependencies { compile 'com.evernote:android-job:1.1.2' } public class App extends Application { @Override public void onCreate() { super.onCreate(); JobManager.create(this).addJobCreator(new ReminderJobCreator()); } }
43. Setup public class ReminderJobCreator implements JobCreator { @Override public Job create(String tag) { switch (tag) { case ReminderJob.TAG: return new ReminderJob(); case SyncJob.TAG: return new SyncJob(); default: return null; } } }
44. Reminder job public class ReminderJob extends Job { public static final String TAG = "ReminderJob"; private static final String EXTRA_ID = "EXTRA_ID"; @NonNull @Override protected Result onRunJob(Params params) { int id = params.getExtras().getInt(EXTRA_ID, -1); if (id < 0) { return Result.FAILURE; } Reminder reminder = ReminderEngine.instance().getReminderById(id); if (reminder == null) { return Result.FAILURE; } ReminderEngine.instance().showReminder(reminder); return Result.SUCCESS; } }
45. Reminder job public static int schedule(@NonNull Reminder reminder) { PersistableBundleCompat extras = new PersistableBundleCompat(); extras.putInt(EXTRA_ID, reminder.getId()); long time = Math.max(1L, reminder.getTimestamp() - System.currentTimeMillis()); return new JobRequest.Builder(TAG) .setExact(time) .setExtras(extras) .setPersisted(true) .setUpdateCurrent(false) .build() .schedule(); }
46. Reminder job public static int schedule(@NonNull Reminder reminder) { PersistableBundleCompat extras = new PersistableBundleCompat(); extras.putInt(EXTRA_ID, reminder.getId()); long time = Math.max(1L, reminder.getTimestamp() - System.currentTimeMillis()); return new JobRequest.Builder(TAG) .setExact(time) .setExtras(extras) .setPersisted(true) .setUpdateCurrent(false) .build() .schedule(); }
47. Sync job public class SyncJob extends Job { public static final String TAG = "SyncJob"; @NonNull @Override protected Result onRunJob(Params params) { new SyncEngine().syncReminders(); return Result.SUCCESS; } }
48. Sync job public static int schedule() { Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG); if (!jobRequests.isEmpty()) { return jobRequests.iterator().next().getJobId(); } long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again return new JobRequest.Builder(TAG) .setPeriodic(interval, flex) .setPersisted(true) .setUpdateCurrent(true) .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED) .setRequiresCharging(true) .setRequirementsEnforced(true) .build() .schedule(); }
49. Sync job public static int schedule() { Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG); if (!jobRequests.isEmpty()) { return jobRequests.iterator().next().getJobId(); } long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again return new JobRequest.Builder(TAG) .setPeriodic(interval, flex) .setPersisted(true) .setUpdateCurrent(true) .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED) .setRequiresCharging(true) .setRequirementsEnforced(true) .build() .schedule(); }
50. Sync job public static int schedule() { Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG); if (!jobRequests.isEmpty()) { return jobRequests.iterator().next().getJobId(); } long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again return new JobRequest.Builder(TAG) .setPeriodic(interval, flex) .setPersisted(true) .setUpdateCurrent(true) .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED) .setRequiresCharging(true) .setRequirementsEnforced(true) .build() .schedule(); }
51. Sync job public static int schedule() { Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG); if (!jobRequests.isEmpty()) { return jobRequests.iterator().next().getJobId(); } long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again return new JobRequest.Builder(TAG) .setPeriodic(interval, flex) .setPersisted(true) .setUpdateCurrent(true) .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED) .setRequiresCharging(true) .setRequirementsEnforced(true) .build() .schedule(); }
52. Sync job public static int schedule() { Set<JobRequest> jobRequests = JobManager.instance().getAllJobRequestsForTag(TAG); if (!jobRequests.isEmpty()) { return jobRequests.iterator().next().getJobId(); } long interval = TimeUnit.HOURS.toMillis(6); // every 6 hours long flex = TimeUnit.HOURS.toMillis(3); // wait 3 hours before job runs again return new JobRequest.Builder(TAG) .setPeriodic(interval, flex) .setPersisted(true) .setUpdateCurrent(true) .setRequiredNetworkType(JobRequest.NetworkType.UNMETERED) .setRequiresCharging(true) .setRequirementsEnforced(true) .build() .schedule(); }
53. android-job Tips & Tricks • Look at the samples in the README • Read the FAQ • Uncertain? Having problems? → Create an issue https://github.com/evernote/android-job
54. Conclusion • Android APIs force you to ◦ do the same thing multiple times ◦ write a lot of boilerplate ◦ catch many gotchas • android-job to the rescue
55. Schedule background jobs at the right time google.com/+vRallev twitter.com/vRallev