Embrace WorkManager

After all of 2018 spent as alpha and beta, WorkManager graduated in 2019 to its first stable release and it is now the recommended solution for scheduling and executing deferrable background tasks in Android.
In this talk we’ll quickly look into which use cases are a good fit for WorkManager, and which are better handled by different tools/APIs. Then we will jump into the API itself covering the different options available, from the simple Worker class to the newer CoroutineWorker.
All this with an eye on how you can (and should) test your Workers and how you can implement some of the few missing features that are not yet covered by WorkManager out of the box.

Transcript

1. Embrace WorkManager
   Pietro Maggi
   @pfmaggi
   

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2. .plan
   ● What is WorkManager
   ● Which Worker class is right for my job
   ● WorkManager’s status
   ● Cancel Work
   ● Unique Work
   ● Periodic Work
   ● Testing WorkManager
   ● WorkManager Configuration
   

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3. Part of Jetpack
   Accelerate
   development
   Eliminate
   boilerplate code
   Build high
   quality, robust
   apps
   

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4. Jetpack categories
   Foundation
   Android KTX
   AppCompat
   Auto
   Benchmark
   Multidex
   Security
   Test
   TV
   Wear OS by Google
   Behavior
   CameraX
   Download manager
   Media & playback
   Notifications
   Permissions
   Preferences
   Sharing
   Slices
   UI
   Animation & transitions
   Emoji
   Fragment
   Layout
   Palette
   Architecture
   Data Binding
   Lifecycles
   LiveData
   Navigation
   Paging
   Room
   ViewModel
   WorkManager
   

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5. WorkManager
   WorkManager is an Android library that runs
   deferrable background work when the work's
   constraints are satisfied.
   

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6. WorkManager
   WorkManager is an Android library that runs
   deferrable background work when the work's
   constraints are satisfied.
   

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7. WorkManager
   WorkManager is an Android library that runs
   deferrable background work when the work's
   constraints are satisfied.
   WorkManager is intended for tasks that require a
   guarantee that the system will run them even if the
   app exits.
   

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8. WorkManager
   WorkManager is an Android library that runs
   deferrable background work when the work's
   constraints are satisfied.
   WorkManager is intended for tasks that require a
   guarantee that the system will run them even if the
   app exits.
   Introducing WorkManager: bit.ly/WM_Introduction
   

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9. I need to run a task
   

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10. Has to finish?
    I need to run a task
    

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11. Has to finish?
    I need to run a task
    NO
    ThreadPool*
    or Coroutines
    *If you have system triggers, use a broadcast receiver to get notified
    

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12. Is Deferrable?
    Has to finish?
    I need to run a task
    YES
    NO
    ThreadPool*
    or Coroutines
    *If you have system triggers, use a broadcast receiver to get notified
    

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13. Is Deferrable?
    Has to finish?
    I need to run a task
    YES
    NO NO
    ThreadPool*
    or Coroutines Foreground Service*
    *If you have system triggers, use a broadcast receiver to get notified
    

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14. Is Deferrable?
    Has to finish?
    I need to run a task
    YES
    NO NO
    ThreadPool*
    or Coroutines Foreground Service*
    WorkManager
    *If you have system triggers, use a broadcast receiver to get notified
    YES
    

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15. ● Asynchronous one-off and
    periodic tasks
    WorkManager Benefits
    Compress
    

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16. Compress
    Upload
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining
    WorkManager Benefits
    Filter Image 2 Filter Image 3
    Filter Image 1
    

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17. Compress
    Upload
    WorkManager Benefits
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining with Input/Output
    Filter Image 2 Filter Image 3
    Filter Image 1
    

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18. Upload
    Compress
    WorkManager Benefits
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining with Input/Output
    ● Constraints
    Filter Image 2 Filter Image 3
    Filter Image 1
    Battery
    not low
    Storage
    not low
    Has
    Network
    

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19. Upload
    Compress
    WorkManager Benefits
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining with Input/Output
    ● Constraints
    ● Handles compatibility
    ● System health best
    practices
    ● Guaranteed execution
    Filter Image 2 Filter Image 3
    Filter Image 1
    Battery
    not low
    Storage
    not low
    Has
    Network
    

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20. WorkManager Benefits
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining with Input/Output
    ● Constraints
    ● Handles compatibility
    ● System health best
    practices
    ● Guaranteed execution
    ● Query state to display in UI
    Uploading...
    

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21. WorkManager Benefits
    ● Asynchronous one-off and
    periodic tasks
    ● Chaining with Input/Output
    ● Constraints
    ● Handles compatibility
    ● System health best
    practices
    ● Guaranteed execution
    ● Query state to display in UI
    Finished
    

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22. Choose the
    Background Scheduler
    API 23+
    JobScheduler*
    YES NO
    AlarmManager and
    BroadcastReceiver
    * Available since API level 21, but used only on devices with API level 23+
    

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23. WorkManager’s Worker classes
    

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24. ListenableWorker
    Worker RxWorker CoroutineWorker*
    * Only available using Kotlin
    Meet the Worker family
    

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25. ListenableWorkers
    class LocationWorker(context : Context, params : WorkerParameters)
    : ListenableWorker(context, params) {
    val future = ResolvableFuture.create()
    override fun startWork(): ListenableFuture {
    if (hasPermissions()) {
    getLocation()
    } else {
    future.set(Result.failure())
    }
    return future
    }
    }
    

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26. ListenableWorkers
    class LocationWorker(context : Context, params : WorkerParameters)
    : ListenableWorker(context, params) {
    val future = ResolvableFuture.create()
    override fun startWork(): ListenableFuture {
    if (hasPermissions()) {
    getLocation()
    } else {
    future.set(Result.failure())
    }
    return future
    }
    }
    

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27. ListenableWorkers
    class LocationWorker(context : Context, params : WorkerParameters)
    : ListenableWorker(context, params) {
    val future = ResolvableFuture.create()
    override fun startWork(): ListenableFuture {
    if (hasPermissions()) {
    getLocation()
    } else {
    future.set(Result.failure())
    }
    return future
    }
    }
    runs on
    main thread
    

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28. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    

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29. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    

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30. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    Needs to be
    Synchronous
    

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31. A CoroutineWorker sample
    class RefreshMainDataWork(context: Context, params: WorkerParameters) :
    CoroutineWorker(context, params) {
    override suspend fun doWork(): Result {
    val database = getDatabase(applicationContext)
    val repository = TitleRepository(MainNetworkImpl, database.titleDao)
    return try {
    repository.refreshTitle()
    Result.success()
    } catch (error: TitleRefreshError) {
    Result.failure()
    }
    }
    }
    

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32. A CoroutineWorker sample
    class RefreshMainDataWork(context: Context, params: WorkerParameters) :
    CoroutineWorker(context, params) {
    override suspend fun doWork(): Result {
    val database = getDatabase(applicationContext)
    val repository = TitleRepository(MainNetworkImpl, database.titleDao)
    return try {
    repository.refreshTitle()
    Result.success()
    } catch (error: TitleRefreshError) {
    Result.failure()
    }
    }
    }
    WorkManager meets Kotlin: bit.ly/WM_Kotlin
    

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33. RxWorker, for the RxJava2 users
    class RxDownloadWorker(context : Context, params : WorkerParameters) :
    RxWorker(context, params ) {
    override fun createWork() : Single {
    return Observable.range(0, 100)
    .flatMap { download("https://www.google.com") }
    .toList()
    .map { Result.success() };
    }
    }
    

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34. WorkManager Dependencies
    dependencies {
    def work_version = '2.0.1'
    implementation "androidx.work:work-runtime:$work_version"
    implementation "androidx.work:work-runtime-ktx:$work_version"
    implementation "androidx.work:work-rxjava2:$work_version"
    androidTestImplementation "androidx.work:work-testing:$work_version"
    }
    

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35. WorkManager Dependencies
    dependencies {
    def work_version = '2.0.1'
    implementation "androidx.work:work-runtime:$work_version"
    implementation "androidx.work:work-runtime-ktx:$work_version"
    implementation "androidx.work:work-rxjava2:$work_version"
    androidTestImplementation "androidx.work:work-testing:$work_version"
    }
    

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36. WorkManager Dependencies
    dependencies {
    def work_version = '2.0.1'
    implementation "androidx.work:work-runtime:$work_version"
    implementation "androidx.work:work-runtime-ktx:$work_version"
    implementation "androidx.work:work-rxjava2:$work_version"
    androidTestImplementation "androidx.work:work-testing:$work_version"
    }
    

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37. WorkManager Dependencies
    dependencies {
    def work_version = '2.0.1'
    implementation "androidx.work:work-runtime:$work_version"
    implementation "androidx.work:work-runtime-ktx:$work_version"
    implementation "androidx.work:work-rxjava2:$work_version"
    androidTestImplementation "androidx.work:work-testing:$work_version"
    }
    

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38. WorkManager Dependencies
    dependencies {
    def work_version = '2.0.1'
    implementation "androidx.work:work-runtime:$work_version"
    implementation "androidx.work:work-runtime-ktx:$work_version"
    implementation "androidx.work:work-rxjava2:$work_version"
    androidTestImplementation "androidx.work:work-testing:$work_version"
    }
    

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39. WorkManager’s Status
    

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40. WorkManager’s WorkRequest
    WorkManager Basics: bit.ly/WM_Basics
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    

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41. WorkManager’s WorkRequest - WorkInfo from UUID
    WorkManager Basics: bit.ly/WM_Basics
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    WorkManager.getInstance().getWorkInfoById(save.id)
    

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42. WorkManager’s WorkRequest - WorkInfo from UUID
    WorkManager Basics: bit.ly/WM_Basics
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    WorkManager.getInstance().getWorkInfoById(save.id)
    WorkManager.getInstance().getWorkInfoByIdLiveData(save.id)
    

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43. WorkManager’s WorkRequest - WorkInfo(s) from TAG
    WorkManager Basics: bit.ly/WM_Basics
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    WorkManager.getInstance().getWorkInfoById(save.id)
    WorkManager.getInstance().getWorkInfoByIdLiveData(save.id)
    WorkManager.getInstance().getWorkInfosByTag(TAG_SAVE)
    

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44. WorkManager.getInstance().getWorkInfosByTagLiveData(TAG_SAVE)
    WorkManager’s WorkRequest - WorkInfo(s) from TAG
    WorkManager Basics: bit.ly/WM_Basics
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    WorkManager.getInstance().getWorkInfoById(save.id)
    WorkManager.getInstance().getWorkInfoByIdLiveData(save.id)
    WorkManager.getInstance().getWorkInfosByTag(TAG_SAVE)
    

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45. RUNNING
    Life of OneTime Work
    ENQUEUED
    SUCCEEDED
    BLOCKED FAILED
    CANCELLED
    RETRY SUCCESS
    FAILURE
    CANCEL
    

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46. Cancel Work
    

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47. Cancel Work
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    WorkManager.getInstance().cancelWorkById(save.id)
    Source: developer.android.com/topic/libraries/architecture/workmanager/how-to/cancel-stop-work
    

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48. Cancel Work
    val save = OneTimeWorkRequestBuilder()
    .addTag(TAG_SAVE)
    .build()
    Source: developer.android.com/topic/libraries/architecture/workmanager/how-to/cancel-stop-work
    WorkManager.getInstance().cancelWorkById(save.id)
    WorkManager.getInstance().cancelAllWorkByTag(TAG_SAVE)
    

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49. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    if (isStopped()) return Result.failure()
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    

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50. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    if (isStopped()) return Result.failure()
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    

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51. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    val in = inputData.getString(KEY_STRING)
    return try {
    // Do something that can fail
    if (isStopped()) return Result.success() // this is not used
    Result.success(workDataOf(KEY_INT to 42))
    } catch (throwable: Throwable) {
    // For errors, return FAILURE or RETRY
    Result.failure()
    }
    }
    }
    

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52. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    // …
    }
    override fun onStopped() {
    super.onStopped()
    // Cleanup
    }
    }
    

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53. Worker
    class MyWorker(ctx: Context, params: WorkerParameters) : Worker(ctx,
    params) {
    override fun doWork(): Result {
    // …
    }
    override fun onStopped() {
    super.onStopped()
    // Cleanup
    }
    }
    

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54. Unique Work
    

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55. Unique Work
    Three different policies for OneTimeWorker:
    ● KEEP
    ● REPLACE
    ● APPEND
    Two different policies for PeriodicWorker:
    ● KEEP
    ● REPLACE
    ● APPEND
    

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56. Unique Work - Periodic
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    val backup = PeriodicWorkRequestBuilder(8, TimeUnit.HOURS)
    .build()
    WorkManager.getInstance().enqueueUniquePeriodicWork((
    "BackupWork",
    ExistingPeriodicWorkPolicy.KEEP,
    myWork)
    }
    }
    

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57. Unique Work - Periodic
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    val backup = PeriodicWorkRequestBuilder(8, TimeUnit.HOURS)
    .build()
    WorkManager.getInstance().enqueueUniquePeriodicWork((
    "BackupWork",
    ExistingPeriodicWorkPolicy.KEEP,
    myWork)
    }
    }
    

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58. Unique Work - Periodic
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    val backup = PeriodicWorkRequestBuilder(8, TimeUnit.HOURS)
    .build()
    WorkManager.getInstance().enqueueUniquePeriodicWork((
    "BackupWork",
    ExistingPeriodicWorkPolicy.KEEP,
    myWork)
    }
    }
    val workManager = WorkManager.getInstance()
    workManager.getWorkInfosForUniqueWorkLiveData("BackupWork")
    

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59. Unique Work - Periodic
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    val backup = PeriodicWorkRequestBuilder(8, TimeUnit.HOURS)
    .build()
    WorkManager.getInstance().enqueueUniquePeriodicWork((
    "BackupWork",
    ExistingPeriodicWorkPolicy.KEEP,
    myWork)
    }
    }
    val workManager = WorkManager.getInstance()
    workManager.getWorkInfosForUniqueWorkLiveData("BackupWork")
    

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60. Periodic Work
    

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61. PeriodicWorkRequest
    Few differences from OneTimeWorkRequest:
    ● No InitialDelay
    

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62. PeriodicWorkRequest
    Few differences from OneTimeWorkRequest:
    ● No InitialDelay
    ● InitialDelay available in WorkManager v2.1.0-alpha02+
    

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63. PeriodicWorkRequest
    Few differences from OneTimeWorkRequest:
    ● No InitialDelay
    ● InitialDelay available in WorkManager v2.1.0-alpha02+
    ● UniqueWork cannot be APPENDED (only KEEP or REPLACE)
    

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64. PeriodicWorkRequest
    Few differences from OneTimeWorkRequest:
    ● No InitialDelay
    ● InitialDelay available in WorkManager v2.1.0-alpha02+
    ● UniqueWork cannot be APPENDED (only KEEP or REPLACE)
    ● There’s no SUCCEEDED state
    

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65. PeriodicWorkRequest
    Few differences from OneTimeWorkRequest:
    ● No InitialDelay
    ● InitialDelay available in WorkManager v2.1.0-alpha02+
    ● UniqueWork cannot be APPENDED (only KEEP or REPLACE)
    ● There’s no SUCCEEDED state (and no FAILED state)
    

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66. RUNNING
    Life of Periodic Work
    ENQUEUED
    CANCELLED
    RETRY, SUCCESS or FAILURE
    CANCEL
    WorkManager Periodicity: bit.ly/WM_Periodic
    

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67. Periodic Work - Initial Delay
    class DelayPeriodicWorker(ctx: Context, params: WorkerParameters) :
    Worker(ctx, params) {
    override fun doWork(): Result {
    // Schedule periodic work
    val periodicRequest = PeriodicWorkRequestBuilder(
    1, TimeUnit.HOURS
    ).build()
    WorkManager.getInstance().enqueue(periodicRequest)
    return Result.success()
    }
    }
    val delayedWorkRequest = OneTimeWorkRequestBuilder()
    .setInitialDelay(6, TimeUnit.HOURS)
    .build()
    WorkManager.getInstance().enqueue(delayedWorkRequest)
    

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68. Testing WorkManager
    

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69. WorkManager TestInitHelper
    targetContext = InstrumentationRegistry.getInstrumentation().targetContext
    WorkManagerTestInitHelper.initializeTestWorkManager(targetContext)
    targetContext = InstrumentationRegistry.getInstrumentation().targetContext
    configuration = Configuration.Builder()
    .setMinimumLoggingLevel(Log.DEBUG)
    .setExecutor(SynchronousExecutor())
    .build()
    WorkManagerTestInitHelper.initializeTestWorkManager(targetContext, configuration)
    Source: developer.android.com/topic/libraries/architecture/workmanager/how-to/testing
    

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70. A sample test
    val inputData = workDataOf(KEY_IMAGE_URI to inputDataUri.toString())
    val request = OneTimeWorkRequestBuilder()
    .setInputData(inputData)
    .build()
    workManager.enqueue(request).result.get()
    val workInfo = workManager.getWorkInfoById(request.id).get()
    val outputUri = workInfo.outputData.getString(KEY_IMAGE_URI)
    assertThat(uriFileExists(targetContext, outputUri), `is`(true))
    assertThat(workInfo.state, `is`(WorkInfo.State.SUCCEEDED))
    Source: developer.android.com/topic/libraries/architecture/workmanager/how-to/testing
    

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71. TestWorkerBuilder and TestListenableWorkerBuilder (v2.1)
    @Before
    fun setup() {
    context = ApplicationProvider.getApplicationContext()
    workManager = WorkManager.getInstance(context)
    }
    @Test
    fun testRefreshMainDataWork() {
    val worker = TestListenableWorkerBuilder(context).build()
    val result = worker.startWork().get()
    assertThat(result, `is` (Result.success()))
    }
    developer.android.com/topic/libraries/architecture/workmanager/how-to/testing-210
    

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72. TestWorkerBuilder and TestListenableWorkerBuilder (v2.1)
    @Test
    fun testMyWorkRetry() {
    val data = workDataOf("SERVER_URL" to "http://fake.url")
    // Get the ListenableWorker with a RunAttemptCount of 2
    val worker = TestListenableWorkerBuilder(context)
    .setInputData(data)
    .setRunAttemptCount(2)
    .build()
    // Start the work synchronously
    val result = worker.startWork().get()
    assertThat(result, `is`(Result.retry()))
    }
    WorkManager meets Kotlin: bit.ly/WM_Kotlin
    

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73. TestWorkerBuilder and TestListenableWorkerBuilder (v2.1)
    @Test
    fun testMyWorkRetry() {
    val data = workDataOf("SERVER_URL" to "http://fake.url")
    // Get the ListenableWorker with a RunAttemptCount of 2
    val worker = TestListenableWorkerBuilder(context)
    .setInputData(data)
    .setRunAttemptCount(2)
    .build()
    // Start the work synchronously
    val result = worker.startWork().get()
    assertThat(result, `is`(Result.retry()))
    }
    WorkManager meets Kotlin: bit.ly/WM_Kotlin
    

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74. TestWorkerBuilder and TestListenableWorkerBuilder (v2.1)
    @Test
    fun testMyWorkRetry() {
    val data = workDataOf("SERVER_URL" to "http://fake.url")
    // Get the ListenableWorker with a RunAttemptCount of 2
    val worker = TestListenableWorkerBuilder(context)
    .setInputData(data)
    .setRunAttemptCount(2)
    .build()
    // Start the work synchronously
    val result = worker.startWork().get()
    assertThat(result, `is`(Result.retry()))
    }
    WorkManager meets Kotlin: bit.ly/WM_Kotlin
    

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75. WorkManager Configuration
    

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76. Why?
    ● Provide your custom executor
    ● Setup a different logging level
    ● Setup a custom WorkerFactory
    

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77. Why?
    ● Provide your custom executor
    ● Setup a different logging level
    ● Setup a custom WorkerFactory (for DI)
    

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78. WorkManager configuration - Disable the default initialization
    AndroidManifest.xml
    android:name="androidx.work.impl.WorkManagerInitializer"
    android:authorities="${applicationId}.workmanager-init"
    tools:node="remove" />
    

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79. WorkManager configuration - Make a new configuration
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    // provide custom configuration
    val config = Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory())
    .build()
    //initialize WorkManager
    WorkManager.initialize(this, config)
    val workManager = WorkManager.getInstance()
    }
    }
    

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80. WorkManager configuration - Make a new configuration
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    // provide custom configuration
    val config = Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory())
    .build()
    //initialize WorkManager
    WorkManager.initialize(this, config)
    val workManager = WorkManager.getInstance()
    }
    }
    

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81. WorkManager configuration - Make a new configuration
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    // provide custom configuration
    val config = Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory())
    .build()
    //initialize WorkManager
    WorkManager.initialize(this, config)
    val workManager = WorkManager.getInstance()
    }
    }
    

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82. WorkManager configuration - Make a new configuration
    class MyApplication: Application() {
    override fun onCreate() {
    super.onCreate()
    // provide custom configuration
    val config = Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory())
    .build()
    //initialize WorkManager
    WorkManager.initialize(this, config)
    val workManager = WorkManager.getInstance()
    }
    }
    

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83. Timeline
    WorkManager
    Initialize
    App Starts
    WorkManager
    executes
    WorkRequests
    

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84. WorkManager configuration - Build your factory
    class MyWorkerFactory(private val appContext: Context) : WorkerFactory() {
    override fun createWorker(appContext: Context,
    workerClassName: String,
    workerParameters: WorkerParameters): ListenableWorker {
    if (workerClassName.equals("com.sample.myWorker")) {
    return UpvoteStoryWorker(appContext, workerParameters)
    } else {
    throw Exception("Unexpected Worker classname: $workerClassName")
    }
    }
    }
    

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85. WorkManager configuration - New 2.1.x on demand initialization
    class MyApplication : Application(), Configuration.Provider {
    override fun getWorkManagerConfiguration(): Configuration =
    // provide custom configuration
    Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory(this))
    .build()
    }
    

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86. WorkManager configuration - New 2.1.x on demand initialization
    class MyApplication : Application(), Configuration.Provider {
    override fun getWorkManagerConfiguration(): Configuration =
    // provide custom configuration
    Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory(this))
    .build()
    }
    

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87. WorkManager configuration - New 2.1.x on demand initialization
    class MyApplication : Application(), Configuration.Provider {
    override fun getWorkManagerConfiguration(): Configuration =
    // provide custom configuration
    Configuration.Builder()
    .setMinimumLoggingLevel(android.util.Log.INFO)
    .setWorkerFactory(MyWorkerFactory(this))
    .build()
    }
    WorkManager.getInstance(context)
    

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88. Dagger?
    

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89. I’m not a Dagger expert!
    - Different requirements
    - Different architectures
    - Different setups
    

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90. Plaid
    

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91. Plaid Modules
    StoryComponent
    CoreComponent
    Dribbble
    Component
    Home
    Component
    About
    Component
    bit.ly/plaid-dagger
    

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92. WorkManager in Plaid
    class UpvoteStoryWorker(appContext: Context,
    workerParams: WorkerParameters,
    private val service: DesignerNewsService)
    : CoroutineWorker(appContext, workerParams) {
    override suspend fun doWork(): Result {
    return try {
    val storyId = inputData.getLong(KEY_STORY_ID, 0)
    val userId = inputData.getLong(KEY_USER_ID, 0)
    val request = UpvoteStoryRequest(storyId, userId)
    val response = service.upvoteStoryV2(request).await()
    if (response.isSuccessful) {
    Result.success()
    } else {
    Result.failure()
    }
    } catch (e: Exception) {
    Result.failure()
    }
    }
    }
    

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93. WorkManager in Plaid
    class UpvoteStoryWorkerFactory(private val service: DesignerNewsService) : WorkerFactory() {
    override fun createWorker(
    appContext: Context,
    workerClassName: String,
    workerParameters: WorkerParameters
    ): ListenableWorker {
    if (workerClassName.equals("io.plaidapp.designernews.worker.UpvoteStoryWorker")) {
    return UpvoteStoryWorker(appContext, workerParameters, service)
    } else {
    throw Exception("Unexpected Worker classname: $workerClassName")
    }
    }
    }
    

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94. DelegatingWorkerFactory (v2.1)
    A WorkerFactory which delegates to other factories. Factories can register
    themselves as delegates, and they will be invoked in order until a delegated
    factory returns a non-null ListenableWorker instance.
    Source: developer.android.com/reference/androidx/work/DelegatingWorkerFactory
    

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95. @Provides
    @FeatureScope
    fun provideWorkManager(service: DesignerNewsService): WorkManager {
    // provide custom configuration
    val appContext = context.applicationContext
    if (appContext is Configuration.Provider) {
    val factory =
    appContext.getWorkManagerConfiguration().workerFactory as
    PlaidWorkerFactory
    factory.addFactory(UpvoteStoryWorkerFactory(service))
    }
    return WorkManager.getInstance(context)
    }
    DelegatingWorkerFactory (v2.1)
    

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96. Things to keep in mind
    - Register your WorkerFactory
    - Renaming a Worker requires to cancel their
    work requests
    - WorkManager and on demand Delivery...
    

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97. Conclusion
    

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98. ● New developments on v2.x branch
    ● Fixes backported to v1.x branch
    ● Use Kotlin? CoroutineWorker
    ● Don’t forget to handle cancellation and stopping
    ● If you need to do something once, make it unique
    ● WorkRequest are persisted in a DB (including Data)
    Few things before I take off..
    

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99. Resources
    Documentation:
    developer.android.com/topic/libraries/architecture/workmanager/
    Codelab:
    codelabs.developers.google.com/codelabs/android-workmanager-kt/
    Release Notes:
    developer.android.com/jetpack/androidx/releases/work
    Working with WorkManager talk at ADS:
    www.youtube.com/watch?v=83a4rYXsDs0
    Guide to background processing:
    developer.android.com/guide/background/
    WorkManager Source Code (part of AOSP):
    android.googlesource.com/platform/frameworks/support/+/master/work
    

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100. Resources
     WorkManager Blog Series:
     ● Introducing WorkManager
     bit.ly/WM_Introduction
     ● WorkManager Basics
     bit.ly/WM_Basics
     ● WorkManager meets Kotlin
     bit.ly/WM_Kotlin
     ● WorkManager Periodicity
     bit.ly/WM_Periodic
     

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101. Q&A
     Pietro Maggi
     @pfmaggi
     

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102. Thank you!
     Pietro Maggi
     @pfmaggi
     

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