RxSwiftでエラーを分岐するTips

potatotips #56 での発表資料です

https://potatotips.connpass.com/event/104242/

Transcript

1. 3Y4XJGUͰΤϥʔΛ෼ذ͢Δ
   5JQT
   ࠓ৓ળۣ!ZJNBKP
   QPUBUPUJQT4NBSU/FXTࣾ։࠵
   ͬͯςΩετ͕ग़͖ͯͨΒͦ͜͸੝Γ্͕ΓϙΠϯτͰ͢ʂ
   3FDZDMFE"MVNJOJVN
   Ҏ߱ͷεϥΠυʹ
   

   View Slide

2. ࣗݾ঺հ
   

   View Slide

3. J04ΞϓϦ։ൃܥͷٕज़ಉਓࢽΛ#005)Ͱެ։͍ͯ͠·͢
   4XJGUBTZODBXBJUݚڀಡຊ
   ԁ
   IUUQTTXJGUCPPUIQN
   
   

   View Slide

4. ͞Βʹࠓ݄৽͘͠ެ։͠·ͨ͠ʂ
   3Y4XJGUݚڀಡຊᶗ
   ԁ
   IUUQTTXJGUCPPUIQN
   
   3FDZDMFE"MVNJOJVN
   

   View Slide

5. ຊ୊
   

   View Slide

6. 3Yͷҟৗऴྃͷݪଇ
   ˣ
   0CTFSWBCMFγʔέϯεʹ
   Τϥʔྲྀ͞ΕΔͱͦΕҎ߱
   ߪಡͰ͖ͳ͘ͳΔ
   ☓
   ☓
   

   View Slide

7. ҟৗॲཧܥͷύλʔ
   ϯ͸৭ʑ
   ΤϥʔΛΩϟονͯ͠PO&SSPSͱͯ͠ྲྀ͞ͳ͍Α͏ʹ͢Δ
   w DBUDI&SSPS\^ͯ͠Τϥʔʹରॲ
   w 0CTFSWBCMF3FTVMUͳܕͰྲྀ͢
   w ͜͜Ͱͷ3FTVMU͸੒൱ͱͦͷ৘ใΛؚΉFOVN
   0CTFSWBCMFγʔέϯεΛ෼ذ͢Δ
   w 0CTFSWBCMF3FTVMUͳܕʹͨ͠΋ͷΛ͞Βʹͭͷγʔέϯεਖ਼ৗͱҟ
   ৗܥʹ෼ذ
   w ࢀߟϝϧΧϦΞοςͷ3Y4XJGU࣮૷ΨΠυIUUQTTQFBLFSEFDLDPNQBSBLFFUZ
   NFSVLBSJBUVUFGBMTFSYTXJGUTIJ[IVBOHHBJEP TMJEF
   

   View Slide

8. 0CTFSWBCMFγʔέϯεΛ
   ਖ਼ৗܥͱΤϥʔͰ෼ذ͢Δͷ͸
   3Y4XJGUͷNBUFSJBMJ[F࢖͑͹
   ָʹͰ͖·͢Αͱ͍͏ͷ͕
   ࠓճͷ5JQT
   

   View Slide

9. ☓
   NBUFSJBMJ[F
   
   &WFOU &WFOU
   ☓ &WFOU
   3YͷNBUFSJBMJ[F
   ϝιουͰΠϕϯτΛSFQSFTFOUͨ͠
   0CTFSWBCMF&WFOU5ͳγʔέϯεΛ৽ͨʹ࡞Δ
   

   View Slide

10. ਖ਼ৗܥͱҟৗܥͷΠϕϯτΛ
    औΓग़ͤΔΑ͏ͳϝιουΛ༻ҙ
    extension ObservableType where E: EventConvertible {
    public func elements() -> Observable {
    return filter { $0.event.element != nil }
    .map { $0.event.element! }
    }
    public func errors() -> Observable {
    return filter { $0.event.error != nil }
    .map { $0.event.error! }
    }
    }
    // 1. ObservableͷE͕EventConvertible४ڌͰ͋Ε͹࢖͑ΔΑ͏ʹͳΔ
    // ྫ͑͹ Observable> ͱ͔
    // 2_1. Πϕϯτͷਖ਼ৗܥelementͷΈΛฦ͢Α͏ʹ͢Δ͚ͩ
    // 2_2. ΠϕϯτͷΤϥʔͷΈΛฦ͢Α͏ʹ͢Δ͚ͩ
    

    View Slide

11. ར༻ྫ
    

    View Slide

12. let result = Observable.of(1, 2)
    .flatMap { _ -> Observable> in
    let observable = Observable.create { observer in
    observer.onNext("A")
    observer.onError(TestError.test)
    observer.onNext(“B")
    observer.onCompleted()
    return Disposables.create()
    }
    return observable.materialize()
    }
    output1 = result
    .elements()
    .subscribe(onNext: {
    print("elements, onNext: \($0)”)
    }, onError: {
    print("elements, onError: \($0)")
    },)
    error = result
    .errors()
    .subscribe(onNext: {
    print("errors, onNext: \($0)")
    }, onError: {
    print("errors, onError: \($0)")
    })
    —— ग़ྗ ——
    elements, onNext: A
    elements, onNext: A
    elements, onCompleted:
    errors, onNext: test
    errors, onNext: test
    errors, onCompleted:
    

    View Slide

13. ͱ͍͏͜ͱͰ
    FMFNFOUT
    ͱFSSPST
    ϝιουΛFYUFOTJPOʹ͠
    ର৅ͷ0CTFSWBCMFγʔέϯεʹ
    NBUFSJBMJ[F
    ͢Δ͚ͩͰ
    FSSPSͷγʔέϯε͕෼ذͰ͖Δʜ
    

    View Slide

14. 7JFX.PEFM
    MFUPVUQVU%SJWFS#PPM
    MFUFSSPS%SJWFS&SSPS
    ͔͠͠
    &SSPSܕͬͯΧόʔൣғ޿͗͢ΔͷͰ͸ʁ
    ࣗલͰΤϥʔ෼ذͯ͠ΔΜ͔ͩΒܕΛ੍ݶ͢Ε͹͍͍ͷʹ
    

    View Slide

15. ྫಛఆͷΤϥʔʹ͢Δ
    let error: Observable = result
    .errors()
    .map {
    guard let error = $0 as? OAuthSwiftError else {
    // ͜͜ͰΫϥογϡϨϙʔτૹΓͭͭ
    ….
    fatalError($0.localizedDescription)
    }
    return error
    }
    .share(replay: 1)
    w Ͱ͖Δ͚Ͳ΋ʜ
    w ΍Δඞཁ͕͋ΔͱࢥͬͨΒ΍ͬͨΒΑΖͦ͠͏
    w .PEFM૚ͷԞਂ͘ͰಛఆͷΤϥʔͷΈΛ૝ఆ͍ͯ͠Δ৔߹ͳͲ
    w ͦ͜·Ͱ΍Δඞཁͳͦ͞͏ͱ൑அͰ͖Δͱ͖
    w 7JFX.PEFMͷϓϨθϯςʔγϣϯϩδοΫͰ&SSPS൑ผ͢Ε͹͍
    ͍ͱ͍͏৔߹ͳͲ
    

    View Slide

16. ͔͠͠ࠔͬͨ͜ͱʹ
    

    View Slide

17. 4JOHMF΍.BZCF $PNQMFUBCMFͰ͸
    ͦͷ··Ͱ͸
    NBUFSJBMJ[F͸࢖͑ͳ͍
    

    View Slide

18. 1SPUPDPM
    0CTFSWBCMF5ZQF
    NBUFSJBMJ[F
    
    1SPUPDPM
    1SJNJUJWF4FRVFODF5ZQF
    $MBTT
    0CTFSWBCMF&
    1SPUPDPM
    0CTFSWBCMF$POWFSUJCMF5ZQF
    4USVDU
    1SJNJUJWF4FRVFODF5SBJU &MFNFOU
    4JOHMFͳͲ
    
    

    View Slide

19. 4JOHMFͰNBUFSJBMJ[FΛ࢖͍͍ͨ৔߹
    BT0CTFSWBCMF
    NFUFSJBMJ[F
    
    

    View Slide

20. ྫ͑͹4JOHMFΛฦ͢ΠϯλϑΣʔε͕
    ͋ͬͨͱͯ͠
    ͦ͏͍͏΋ͷ͸
    BT0CTFSWBCMF
    NFUFSJBMJ[F
    
    ͢Δ͜ͱʹΑͬͯ
    0CTFSWBCMF&WFOU3FTQPOTF
    ͱͳΔ
    func request(_ param: RequestParam) -> Single {}
    

    View Slide

21. ͦ΋ͦ΋
    ͳͥ͜ͷ෼ذํ๏ʹ
    ؾ͍͔ͮͨ
    

    View Slide

22. 3Y4XJGU&YU
    IUUQTHJUIVCDPN3Y4XJGU$PNNVOJUZ3Y4XJGU&YU
    w FMFNFOUT
    FSSPST
    
    w VOXSBQ
    
    w JHOPSF @WBMVFT5P*HOPSF&ʜ
    
    w OPU
    
    w pMUFS.BQ\^
    FUD
    

    View Slide

23. IUUQTHJUIVCDPN3FBDUJWF93Y4XJGUQVMM
    3Y4XJGU
    
    ͦ΋ͦ΋ઌʹ3Y4XJGU&YUͰNBUFSJBMJ[F͕࣮૷͞Ε
    ͦΕ͕3Y4XJGUʹऔΓࠐ·Εͨ
    

    View Slide

24. ·ͱΊ
    w ΤϥʔΛ෼ذ͍ͨ͠ͱ͖͸0CTFSWBCMF&WFOU5
    w NBUFSJBMJ[F
    ݺ΂͹ˢʹͳΔ
    w &WFOUͷpMUFSͱNBQ͢ΔϝιουͰͭʹ෼ذ
    w &SSPSΛ೚ҙͷ&SSPSʹͰ͖ΔͷͰ΍ͬͯ΋͍͍
    w NBUFSJBMJ[F
    ͸0CTFSWBCMF5ZQFʹ͔࣮͠૷͞Ε͍ͯͳ͍
    ͷͰ4JOHMF .BZCF $PNQMFUFEͳͲͰ͸࢖͑ͳ͍
    

    View Slide

25. Ҏ্Ͱ͢
    ͝ਗ਼ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠
    

    View Slide