132 lines
4.1 KiB
Swift
132 lines
4.1 KiB
Swift
/*:
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> # IMPORTANT: To use **Rx.playground**:
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1. Open **Rx.xcworkspace**.
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1. Build the **RxSwift-OSX** scheme (**Product** → **Build**).
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1. Open **Rx** playground in the **Project navigator**.
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1. Show the Debug Area (**View** → **Debug Area** → **Show Debug Area**).
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----
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[Previous](@previous) - [Table of Contents](Table_of_Contents)
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*/
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import RxSwift
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/*:
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# Error Handling Operators
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Operators that help to recover from error notifications from an Observable.
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## `catchErrorJustReturn`
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Recovers from an Error event by returning an `Observable` sequence that emits a single element and then terminates. [More info](http://reactivex.io/documentation/operators/catch.html)
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*/
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example("catchErrorJustReturn") {
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let disposeBag = DisposeBag()
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let sequenceThatFails = PublishSubject<String>()
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sequenceThatFails
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.catchErrorJustReturn("😊")
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.subscribe { print($0) }
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.addDisposableTo(disposeBag)
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sequenceThatFails.onNext("😬")
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sequenceThatFails.onNext("😨")
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sequenceThatFails.onNext("😡")
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sequenceThatFails.onNext("🔴")
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sequenceThatFails.onError(TestError.test)
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}
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/*:
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----
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## `catchError`
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Recovers from an Error event by switching to the provided recovery `Observable` sequence. [More info](http://reactivex.io/documentation/operators/catch.html)
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*/
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example("catchError") {
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let disposeBag = DisposeBag()
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let sequenceThatFails = PublishSubject<String>()
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let recoverySequence = PublishSubject<String>()
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sequenceThatFails
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.catchError {
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print("Error:", $0)
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return recoverySequence
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}
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.subscribe { print($0) }
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.addDisposableTo(disposeBag)
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sequenceThatFails.onNext("😬")
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sequenceThatFails.onNext("😨")
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sequenceThatFails.onNext("😡")
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sequenceThatFails.onNext("🔴")
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sequenceThatFails.onError(TestError.test)
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recoverySequence.onNext("😊")
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}
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/*:
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----
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## `retry`
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Recovers repeatedly Error events by resubscribing to the `Observable` sequence, indefinitely. [More info](http://reactivex.io/documentation/operators/retry.html)
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*/
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example("retry") {
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let disposeBag = DisposeBag()
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var count = 1
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let sequenceThatErrors = Observable<String>.create { observer in
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observer.onNext("🍎")
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observer.onNext("🍐")
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observer.onNext("🍊")
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if count == 1 {
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observer.onError(TestError.test)
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print("Error encountered")
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count += 1
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}
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observer.onNext("🐶")
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observer.onNext("🐱")
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observer.onNext("🐭")
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observer.onCompleted()
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return Disposables.create()
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}
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sequenceThatErrors
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.retry()
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.subscribe(onNext: { print($0) })
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.addDisposableTo(disposeBag)
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}
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/*:
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----
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## `retry(_:)`
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Recovers repeatedly from Error events by resubscribing to the `Observable` sequence, up to `maxAttemptCount` number of retries. [More info](http://reactivex.io/documentation/operators/retry.html)
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*/
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example("retry maxAttemptCount") {
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let disposeBag = DisposeBag()
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var count = 1
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let sequenceThatErrors = Observable<String>.create { observer in
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observer.onNext("🍎")
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observer.onNext("🍐")
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observer.onNext("🍊")
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if count < 5 {
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observer.onError(TestError.test)
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print("Error encountered")
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count += 1
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}
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observer.onNext("🐶")
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observer.onNext("🐱")
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observer.onNext("🐭")
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observer.onCompleted()
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return Disposables.create()
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}
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sequenceThatErrors
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.retry(3)
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.subscribe(onNext: { print($0) })
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.addDisposableTo(disposeBag)
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}
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//: [Next](@next) - [Table of Contents](Table_of_Contents)
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