![Build Your Own RAC
extension SignalType {
/// Returns a signal that will yield an array of values when `self` completes.
@warn_unused_result(message="Did you forget to call `observe` on the signal?")
public func collect() -> Signal<[Value], Error> {
return self
.reduce(CollectState()) { $0.append($1) }
.map { $0.values }
}
}](https://image.slidesharecdn.com/ios-rac-160415151910/85/iOS-Reactive-Cocoa-Pipeline-32-320.jpg)
iOS Reactive Cocoa Pipeline
- 1. Рак мозга или мозг рака Раком можно все
- 2. 1023
- 4. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer
- 5. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Persistence Notifications Runtime
- 6. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer NSNotification LocationUpdate
- 7. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Networking Networking policies
- 8. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer HTTP.Request HTTP.Response HTTP.Error
- 9. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer API Request Persistence Request Application Service wrapper
- 10. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Update request Value Object Service Object
- 11. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Business logic Logic state
- 12. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Model Object
- 13. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Application State Presentation Logic
- 14. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Bindings Presentables
- 15. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Presentation UI State
- 16. •Application Layer •Transport Layer •Service Layer •Model Layer •ViewModel Layer •View Layer Presenters UIObjects Foundation Types
- 17. Data Flow
- 18. 1024
- 19. Data + Data Request Flow
- 20. Transport Layer
- 21. Transport Layer
- 22. Transport Layer + Errors
- 23. Transport Layer + Binding
- 24. And now?
- 25. RAC • Signal • SignalProducer • Action • Property • Result
- 26. RAC • Signal • SignalProducer • Action • Property • Result • Pipeline • Future Task • Future Builder • Reactive State • Enum<Value | Error>
- 27. RAC • Signal • SignalProducer • Action • Property • Result • NSNotificationCenter • startWithCompletion: • startWithInput:Completions • value + KVO • completions(result, error)
- 28. RAC + Transforms • Signal -> Signal - Operator • Signal.map(transform) • Signal.retry(3) • Signal -> Signal -> Signal - pipeline - retry(map(signal, transform), 3) ✓ signal.map(transform).retry(3)
- 29. RAC + (flat)map
- 30. Transport Layer + RAC
- 31. Transport Layer + RAC let requestAction = Action<URLRequest, URLResponse, Error> { .../*future task*/ } let http = Action<Request, Response, Error> { request in return Result<Request, Error>(value: request) .flatMap(serialize) //Result<JSON, Error> .flatMap(requestBuilder(forConfiguration: configuration)) //Result<URLRequest, Error> .map(SignalProducer.init) //SignalProducer<URLRequest, Error> .flatMap(.Latest, transform: requestAction.apply) //SignalProducer<URLResponse, Error> .attemptMap(deserialize) //SignalProducer<Response Error } Заметьте - эта штука вполне может быть общей вне зависимости от входных и выходных данных засчет generic
- 32. Build Your Own RAC extension SignalType { /// Returns a signal that will yield an array of values when `self` completes. @warn_unused_result(message="Did you forget to call `observe` on the signal?") public func collect() -> Signal<[Value], Error> { return self .reduce(CollectState()) { $0.append($1) } .map { $0.values } } }
- 33. Transport Layer + RAC let httpWithPolicy = Action<Request, Response, Error> { request in http.apply(request) .retry(3) .suspendOn(enterBackgroundSignal: background, enterForeground: foreground) }
- 34. Service Layer
- 35. Service Layer
- 36. Service Layer + RAC let service = Action<Number, Image, Error> { number in let image = cacheService.inquire .apply(number) .concat { xkcdImageHTTP.apply(number) } let description = xkcdDescriptionHTTP.apply(number) return combineLatest(image, description).map { ImageWithDescription(image: $0, description: $1) } }
- 37. Model Layer
- 38. Model Layer
- 39. Model Layer + RAC struct State { let number: Int let value: AnyProperty<ImageWithDescription?> init(number: Int) { self.number = number self.value = AnyProperty(value: nil, producer: service.apply(number)) } } let state = MutableProperty(State(number: 100)) let increment = { number.value = State(number: number.value.number + 1) } let exposedState = AnyProperty(state)
- 40. View Model Layer
- 41. View Model Layer
- 42. VM Layer + RAC let image = model.exposedState .flatMap { $0.value.image } .map { $0 ?? imagePlaceholder } let description = model.exposedState .flatMap { $0.value.description } .map { $0 ?? "Loading..." } let rightButtonAction = model.increment let present = { presenters in presenters.rightButtonAction <~ rightButtonAction presenters.description <~ description.producer presenters.image <~ description.image }
- 43. View Layer
- 44. View + RAC class View { //{ self.imageView.image = $0 } let image: Presenter<UIImage> = self.imageView.imagePresenter //{ self.descriptionLabel.value = $0 } let description: Presenter<String> = self.descriptionLabel.textPresenter //{ self.button.clickedSignal.observe($0) } let rightButton: Presenter<() -> ()> = self.button.clickActionPresenter }
- 45. Hm…
- 46. Benefits? • Consistency • Observability • Testability • Encapsulation • Completeness
- 47. Examples? Popup Action Navigation Property + Actions UIKit Sinks + Presentables Login Form Action + Operators
- 48. What’s next? • RXMarbles (http://rxmarbles.com/) • Reactive Cocoa sources - all here
- 49. Questions?