Hiring WorkManager for your Background Jobs

WorkManager is a component of the Jetpack library. Being a wrapper around the existing background processing libraries, it provides a clever way to handle background tasks in Android.

Get an overview of the existing background processing options in Android. Understand why there was a need for a new API like WorkManager and how it works under the hood. Learn about its components and explore its features such as recurring tasks, chaining of tasks, specifying constraints and passing data to/reading data from tasks.

External links:
WorkManager article series on Medium - bit.ly/wm-series
Resources link on Google docs- bit.ly/wm-res

Presented at GDG DevFest Bangalore 2019.

Transcript

1. Hiring WorkManager for your Background Jobs Mahima MS Android Dev @ Stasis Co-organizer @ WomenDroid @mahi_amy stasislabs.com
2. Nightmares
3. How do I do background work?
4. How do I do background work? Handlers/Threads Services/IntentServices AsyncTasks
5. How do I do background work? Handlers/Threads Services/IntentServices AsyncTasks AlarmManager GCMNetworkManager
6. How do I do background work? Handlers/Threads AsyncTasks Loaders AlarmManager GCMNetworkManager android-job Services/IntentServices
7. How do I do background work? Handlers/Threads SyncAdapters JobScheduler AsyncTasks Loaders AlarmManager GCMNetworkManager android-job priority job queue Services/IntentServices
9. How do I do background work? Handlers/Threads SyncAdapters JobScheduler AsyncTasks Loaders AlarmManager GCMNetworkManager android-job priority job queue Services/IntentServices
10. How do I do background work? Handlers/Threads Services/IntentServices SyncAdapters JobScheduler AsyncTasks Loaders AlarmManager GCMNetworkManager android-job priority job queue
11. How do I do background work? Handlers/Threads Services/IntentServices SyncAdapters JobScheduler AsyncTasks Loaders AlarmManager GCMNetworkManager android-job priority job queue
12. How do I do background work? JobScheduler Loaders AlarmManager priority job queue Handlers/Threads Services/IntentServices SyncAdapters AsyncTasks GCMNetworkManager android-job
13. How do I do background work? Handlers/Threads Services/IntentServices SyncAdapters JobScheduler AsyncTasks Loaders AlarmManager GCMNetworkManager android-job priority job queue
14. Don’t let the battery drain Doze Doze-on-the- go Background Service limitations App Standby buckets
16. Say Hello! WORKMANAGER
17. Under the hood API level ≥ 23 JobScheduler AlarmManager + Broadcast Receivers yes no
18. Components Worker WorkRequest Work Database Enqueue WorkManager WorkResult Data Publish Constraints Retry Data Work Save ID
19. Inside the Database ID State Class Input merger i/p o/p Initial delay Interval duration Back off policy Back off delay Requires n/w 08d7e. 2 Uplo.. Overwr . 654 44 0 0 0 15000 1 d8d9... 0 Sync.. Overwr . Pup 890 15 60000 1 5000 0 WorkSpec
20. USING WORKMANAGER
21. Furrever • Display dog photos • Send a notification everyday with a random dog photo • Share multiple dog photos to friends
22. class GetAllDogsWorker(context: Context, params: WorkerParameters) : Worker (context, params) { override fun doWork(): Result { // fetch data from API return Result.success() } } Define a work <.../>
24. val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .build() Periodic WorkRequest val getRandomDogWorkRequest = PeriodicWorkRequestBuilder<GetRandomDogWorker> (24,TimeUnit.HOURS) .build() OneTime WorkRequest <.../> <.../> 10 mins
25. WorkManager .getInstance(context) .enqueue(getDogsWorkRequest) val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .build()
26. val constraints = Constraints.Builder() .setRequiredNetworkType(CONNECTED) .setRequiresCharging(true) .build() val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .setConstraints(constraints) .build() Constraints <.../>
27. val apiUrlData = workDataOf(Constants.KEY_API_URL to url) val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .setInputData(apiUrlData).build() Defining Input/Output <.../> 10KB
28. val apiUrlData = workDataOf(Constants.KEY_API_URL to url) val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .setInputData(apiUrlData).build() Defining Input/Output <.../> Room DB
29. class GetAllDogsWorker(context: Context, params: WorkerParameters) : Worker(context, params) { override fun doWork(): Result { val apiUrl = getInputData().getString(KEY_API_URL) val response = getDogs(apiUrl) val outputData = workDataOf(KEY_NUM_DOGS to response.dogCount) return Result.success(outputData) } }
30. WorkManager.getInstance(context) .getWorkInfoByIdLiveData(getDogsWorkRequest.id) .observe(lifecycleOwner, Observer { workInfo -> if (workInfo != null && workInfo.state == WorkInfo.State.SUCCEEDED) { progressBar.visibility = View.GONE } }) <.../> Observing Work status
31. val getDogsWorkRequest = OneTimeWorkRequestBuilder<GetAllDogsWorker>() .addTag("fetch") .build() ➔ cancelAllWorkByTag("fetch") Grouping tasks using a tag <.../>
32. States of a One Time Worker Blocked Enqueued Running Failed Succeeded Cancelled Retry Success Failure Cancel
33. Enqueued Running Cancelled Retry, Success or Failure Cancel States of a Periodic Worker
34. WorkManager.getInstance(context) .beginWith(listOf(filter1, filter2)) .then(compress) .then(email) .enqueue() Chaining of tasks<.../>
35. val compress: OneTimeWorkRequest = OneTimeWorkRequestBuilder<CompressWorker>() .setInputMerger(ArrayCreatingInputMerger::class) .build() Input Mergers<.../> • OverwritingInputMerger • ArrayCreatingInputMerger
36. Input Mergers<.../> FilterWorkRequest1 Key 1 5 Key 2 “Pup” FilterWorkRequest2 Key 1 8 Key 2 4 CompressWorker Key 1 8 Key 2 Exception CompressWorker Key 1 [5, 8] Key 2 Exception Overwrite Array
37. • REPLACE • KEEP Unique Work WorkManager.getInstance(context) .enqueuePeriodicWork(“notifyUniqueWork”, ExistingPeriodicWorkPolicy.KEEP, notifyPeriodicWorkRequest) • APPEND
38. Custom Configuration Disable Default Initializer Implement Configuration. Provider Override getWorkManager Configuration() WorkManager.getInstance(context)
39. @Test fun testGetDogsWorker() { val worker = TestWorkerBuilder<GetAllDogsWorker>( // define context & executor inputData = workDataOf(API_URL to url)).build() val result = worker.doWork() assertThat(result, `is`(Result.success())) } Testing your Work<.../>
41. Deep dive WorkManager Resources bit.ly/wm-res ✍ WorkManager article bit.ly/wm-series Furrever demo app github.com/amy6/furrever
42. Thank you! @mahi_amy