Clean Architecture the Right Way. Or almost...

Transcript

1. ≥ Clean Architecture the Right Way (Or almost…)
2. ≥ That’s not clean architecture!
3. ≥ View
4. ≥ View Activity / Fragment
5. ≥ Activity / Fragment View View models
6. ≥ Activity / Fragment View models View Presenter / ViewModel
7. ≥ Activity / Fragment View models Presenter / ViewModel View Domain
8. ≥ Activity / Fragment View models View Domain Presenter / ViewModel Use Case Use Case …
9. ≥ Activity / Fragment Use Case Use Case … View models View Domain Presenter / ViewModel Entities
10. ≥ Activity / Fragment Use Case Use Case … Entities View models View Domain Presenter / ViewModel Mapper
11. ≥ Activity / Fragment Use Case Use Case … Entities View models Mapper View Domain Presenter / ViewModel Repository … Repository
12. ≥ Activity / Fragment Use Case Use Case … Repository Entities … View models Mapper View Domain Repository Presenter / ViewModel Data
13. ≥ Activity / Fragment Use Case Use Case … Repository Entities … View models Mapper View Domain Data Repository Presenter / ViewModel Repository Impl Repository Impl
14. ≥ Activity / Fragment Use Case Use Case … Repository Entities … View models Mapper View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Data Source … Data Source
15. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … View models Mapper View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Database Remote API
16. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … View models Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Data models
17. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Mapper
18. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
19. ≥ 1. What complies with Clean Architecture
20. ≥ Architectural Drinking Game!
21. ≥
22. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
23. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Entities
24. ≥
25. ≥ Activity / Fragment … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Use Case Use Case
26. ≥
27. ≥ Activity / Fragment Use Case Use Case … Repository … Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Data Source Data Source Presenter / ViewModel
28. ≥
29. ≥ Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Activity / Fragment Database Remote API
30. ≥ “Typically the data that crosses the boundaries is simple data structures. You can use basic structs or simple Data Transfer objects if you like […] We don’t want to cheat and pass Entities or Database rows. ”
31. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel Data models View models Mapper Mapper
32. ≥ 2. What’s not in the specification of Clean Architecture
33. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
34. ≥ Activity / Fragment Use Case Use Case … Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Presenter / ViewModel Repository Repository Repository Impl Repository Impl
35. ≥ “[…] use cases orchestrate the flow of data to and from the entities, and direct those entities to use their enterprise wide business rules to achieve the goals of the use case.”
36. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
37. ≥ Activity / Fragment Use Case Use Case … Data Source … Data Source Entities Data models View models Mapper Mapper Database Remote API View Domain Data Presenter / ViewModel
38. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
39. ≥ Activity / Fragment Use Case Use Case … Repository Data Source … Data Source Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Repository Impl Repository Impl Presenter / ViewModel
40. ≥ Activity / Fragment Use Case Use Case … Repository Data Source Impl … Data Source Impl Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Data Source Data Source Presenter / ViewModel
41. ≥ Activity / Fragment Use Case Use Case … Repository Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository … Data Source Impl Data Source Impl Data Source Data Source Presenter / ViewModel
42. ≥ “[…] a set of adapters that convert data from the format most convenient for the use cases and entities, to the format most convenient for some external agency such as the Database”
43. ≥ Activity / Fragment Use Case Use Case … Repository Data Source Impl Data Source Impl Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Data Source Data Source Presenter / ViewModel …
44. ≥ Activity / Fragment Use Case Use Case … Repository Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository … Adapter Impl Adapter Impl Adapter Interface Adapter Interface Adapter
45. ≥
46. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Adapter Interface Adapter Interface Adapter …
47. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API View Domain Data Repository Adapter Interface Adapter Interface Adapter …
48. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API Frameworks Enterprise business rules Frameworks Repository Adapter Interface Adapter Interface Adapter Application business rules …
49. ≥ 3. Bending the rules
50. ≥ + modules, - compilation time
51. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl … Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API Frameworks Enterprise business rules Frameworks Repository Adapter Interface Adapter Interface Adapter Application business rules
52. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API Frameworks Frameworks Repository Adapter Interface Adapter Interface Adapter Application business rules … Domain
53. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API Domain Repository Adapter Interface Adapter Interface Adapter Application business rules … UI Storage Remote
54. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface Adapter … Remote N x Feature business rules
55. ≥ Presentation logic
56. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote Adapter
57. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote Presenter
58. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models View models Mapper Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote Presenter
59. ≥ Activity / Fragment Use Case Use Case … Repository Adapter Impl Adapter Impl Entities … Data models Mapper Database Remote API Domain Storage Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … Remote View Interface UI
60. ≥ Almost TDD
61. ≥ Use Case Use Case … Repository … Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … Activity / Fragment Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API Domain Storage Remote UI View Interface
62. ≥ Use Case Use Case … Repository … Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … View Interface
63. ≥ States with sealed classes
64. ≥ Use Case Use Case … Repository … Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … View Interface Activity / Fragment Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API Domain Storage Remote UI
65. ≥ Use Case Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … View Interface Activity / Fragment Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API Domain Storage Remote UI
66. ≥ Use Case Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … State View Interface Activity / Fragment Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API Domain Storage Remote UI
67. ≥ sealed class State<out T : Any> class Loaded<out T : Any>(val data: T) : State<T>() class Loading() : State<Nothing>() class Error(val message: String) : State<Nothing>()
68. ≥ fun loadProduct(productId: String) { val productDetailsState = getProductDetails.execute(productId) when(productDetailsState) { is Error -> view.renderDetailsError(productDetailsState.message) is Loading -> view.renderLoading() is Loaded -> view.renderDetails(productDetailsState.data) } }
69. ≥ FP for error managing
70. ≥ fun onPhoneNumberVerification(phoneNumber: String) { val result = checkPhoneNumber.execute(phoneNumber) result.fold({ view.renderGenericError }, { checkPhoneState(it) }) } private fun checkPhoneState(state: VerificationState) { when (state) { is Invalid -> view.renderInvalidError() is ExhaustedAttempts -> view.renderExhaustedAttempts(state.code) is Verified -> view.navigateToSuccess() } }
71. ≥ fun onPhoneNumberVerification(phoneNumber: String) { val result = checkPhoneNumber.execute(phoneNumber) result.fold({ view.renderGenericError }, { checkPhoneState(it) }) } private fun checkPhoneState(state: VerificationState) { when (state) { is Invalid -> view.renderInvalidError() is ExhaustedAttempts -> view.renderExhaustedAttempts(state.code) is Verified -> view.navigateToSuccess() } }
72. ≥ Extended Entities
73. ≥ Activity / Fragment Use Case Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … Remote State View Interface
74. ≥ Activity / Fragment Use Case Adapter Impl Adapter Impl Data models Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote State View Interface Entities Presenter
75. ≥ Use Case Adapter Impl Adapter Impl Data models Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote State View Interface Activity / Fragment Entities Presenter
76. ≥ Use Case Adapter Impl Adapter Impl Data models Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface N x Feature business rules … Remote State View Interface Activity / Fragment Presenter Entities
77. ≥ class Product( val id: String, val name: String, val price: String, val image: String, val description: String, val distanceInMeters: Int ) Domain module UI module internal fun Product.getPriceInEuros() = "$price €"
78. ≥ Activity / Fragment Use Case Adapter Impl Adapter Impl Entities Data models Mapper Database Remote API UI Domain Storage Repository Adapter Interface Adapter Interface Presenter N x Feature business rules … Remote State View Interface
79. ≥ Testable Asynchronous Presenters
80. ≥ Different asynchronous approaches •Use Case executed inside a ThreadPoolExecutor •Presenter subscribes to a Use Case (RxJava) •Coroutines for a “synchronous” code
81. ≥ class PhoneVerificationPresenter( private val checkVerificationStatus: CheckVerificationStatusUseCase, ) { //… fun onViewLoaded() { launch(UI) { val state = async { checkVerificationStatus.execute() }.await() checkVerificationState(state) } } //…
82. ≥ class PhoneVerificationPresenter( private val checkVerificationStatus: CheckVerificationStatusUseCase, ) { //… fun onViewLoaded() { launch(UI) { val state = async { checkVerificationStatus.execute() }.await() checkVerificationState(state) } } //…
83. ≥ class PhoneVerificationPresenter( private val checkVerificationStatus: CheckVerificationStatusUseCase, ) { //… fun onViewLoaded() { launch(mainContext) { val state = async(backgroundContext) { checkVerificationStatus.execute() }.await() checkVerificationState(state) } } //…
84. ≥ object CoroutineContexts { lateinit var mainContext: CoroutineContext lateinit var backgroundContext: CoroutineContext }
85. ≥ public class Application extends android.app.Application { //… private void setCorutineContexts() { CoroutineContexts.mainContext = WallapopContexts.getMain(); CoroutineContexts.backgroundContext = WallapopContexts.getBackground(); } //… }
86. ≥ var WALLAPOP_MAIN: CoroutineContext = UI var WALLAPOP_BG: CoroutineContext = newFixedThreadPoolContext(2 * Runtime.getRuntime().availableProcessors(), "bg") object WallapopContexts { @JvmStatic var main = WALLAPOP_MAIN @JvmStatic var background = WALLAPOP_BG }
87. ≥ @Test fun `render verification code when status is Verified`() { whenever(checkStatus.execute()).doReturn(Verified()) presenter.onViewLoaded() verify(view).renderSuccess() }
88. ≥ abstract class UnitTest { init { CoroutineContexts.mainContext = CoroutineContextForTest CoroutineContexts.backgroundContext = CoroutineContextForTest } }
89. ≥ object CoroutineContextForTest : CoroutineDispatcher() { override fun dispatch(context: CoroutineContext, block: Runnable) { block.run() } }
90. ≥ Wrap up
91. ≥ Given a team… •The app you have to develop •The problems you have to solve •The rules you have to follow •The trade offs you have to evaluate •The agreements you decide to take
92. ≥ Your architecture
93. ≥ Thank you!
94. ≥ Q & A Rubén Serrano @akelael ruben.serrano@wallapop.com
95. ≥ Rubén Serrano @akelael ruben.serrano@wallapop.com We’re hiring!