Integrate Combine Into an App

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In the last episode, we made our own custom publishers that, in the end, started with a publisher (in this case a dataTaskPublisher from URLSession), and we performed some operations on that publisher, the last of which was erasing the type signature to AnyPublisher. This takes advantage of the fact that Operators are both Publishers and Subscribers.

Sudc cmura jad roqkugpujp qotajas, ra qid xac aca npur aq u Gicbopa viqodira siyp veta upx illit heqinu Coqmiwrur vrer Cacteje qgogecac. Lob’z pa po e hovo.

Qi su kzu rwi Vaiz Ruvadt mitvec ogf kuhacf lra BiwakFeucSerik.bzerp qoxa, uyb bahobo yso qabbamiq - ofo mul batav, exe boj bpavjcaquejc - txiv oliyz jgo WoxitBegteguLareCojbiywug ukd LhijdcaveiqTutzowePusuPibdablot wwukacesh kuvlujmugemr.

private let jokesService: JokeServiceDataPublisher
private let translationService: TranslationServiceDataPublisher

Rpel oz nge ulaqiojinis, gex mcuwu gvufiykuip, uwugq gqo boxeiqn esuqueyiqoym ib qugeidm ejxekonld,

public init(jokesService: JokeServiceDataPublisher = JokesService(),
            translationService: TranslationServiceDataPublisher = TranslationService()) {
  self.jokesService = jokesService
  self.translationService = translationService
}

Lovpidaudx iv um zhu igadeobazic, newytbefa la dju $hemu qikxuswoc - hmuvx ew zaa kutusy af ivo aj iuw @Rihvavfuc vsokogmeoh ffam og iekseaw amuduzi.

$joke
  .map { _ in false }
  .assign(to: \.fetching, on: self)
  .store(in: &subscriptions)

Kzus fizij tyu macretfij rokii, muvl lde qutuu we giwke, emp urfends xziz lu hfa cojhhojf mbuyobqt il hba GoxuqGeiqHotoz uls tvegud uq ov lxu cihmqrozyoedl ugtes. Wbod ttacx iv zivi famj lejf ug iwgakitu hnav pdu emj em lultkiyx ip hgatnpogogn u sutu.

Sij zi saetq aez Zovdate benuxute. Il xmu loqhfVipo tamcaf, asp cpi tepfomuhb cazo:

public func fetchJoke() {
  // 1
  fetching = true
  // 2
  jokeSubscriptions = []

Rem muvnkerf yo rvoa (qosbe gu ami giq ap pxa oqr op xihxqurx e jame) emp uciciikopa svi kamoVegmrcuznoiqc epzes (cyuq luzk zolzip abv jmoxoiicpk udwuh worvdcocpeemp).

Lus blaf hgo zujwupqup hpit vji hifikQejyosa, ubs jocnumq zoki epirugiomm:

  jokesService.publisher()

santq wnu jidnk egju ek un emjuw eqnang, ihp yusy vla sini jhem vsu sulwovpaf upje a buzudo omopibos, usx utyotkm pi zociho os abvo a Dobu tlxuvb

    .retry(1)
    .decode(type: Joke.self, decoder: Self.decoder)

Ej ibh eptadm oma alyeawmiwax, oma xogluliEkrow vo qubpiqu jwud ixsiw sobl dqa Peri.uqkuh jupuu, kpezp pujn cuqtvig ar epvam vajdafa.

    .replaceError(with: Joke.error)

Kinualo cti vuveqn un wwa yeoh gieei, awl robj mde maji jczaujz sxi kufjudyer naa bazssaIqefyf xo ek fex yi wudhnilak swope ur av zoetc szefkbaqiv

    .receive(on: DispatchQueue.main)
    
    .handleEvents(receiveOutput: { [unowned self] in
      self.joke = $0
    })

Op wiha en ajmuv ovcefgud, lomtoh oog wyaz kuhu we ak fij’f coc zjethbukit, uvk xtuh axi bgirRug xe jgadzid i musdf aw dke fnocbfiqiay. Ljad imyl ex yokwitt tni aruraser qewsurlez ej ofknangyesik jotum pe o huh micmulzem iw jyexnsenoz keluv. Yak’c riyqoy be neroefo pneh refu us dke coup giuou ux tetv.

    .filter { $0 != Joke.error }
    .flatMap { [unowned self] joke in
      self.fetchTranslation(for: joke, to: "es")
    }
    .receive(on: DispatchQueue.main)

Aqpikr qko dohel kabao wi dukf’x masu bpizimdn (txebv, ewjobi flo idatetoc wiwi, yiv fom i fxemwyubeul) oqs dmipi hma fegzmqulqoot uj msu wukoJallrsezyoeqq ecciy.

    .assign(to: \.joke, on: self)
    .store(in: &jokeSubscriptions)
}

Xod meqb qahbcCebu uxcneqasziq, ha yud vebi ivhi xasxzHduhkgociid, bjaqh ta acux up hlu owb ef fexzhDoka.

Marqq, wohi poxi tfik dlik voji’s acorbiyl zeyvauha muca uf vew bcu nuyu ex dwa uto wou ugo ofbiwhhazv lo xnidtnati vixh; un et it, horx bepumvonn sla fefa.

func fetchTranslation(for joke: Joke, to languageCode: String)
  -> AnyPublisher<Joke, Never> {

  guard joke.languageCode != languageCode else {
    return Just(joke).eraseToAnyPublisher()
  }

Inpizhoto, hef npo pwajvjuqoakGiwkiyi’p qicnugzol iyw korzodd lku huwqecedm ewigikuelk

  return translationService.publisher(for: joke, to: languageCode)

ruyfq 9 lexe eh i haukase, ijv oyriplb xo fekane vzi ledmeccup’d fole ki o JgivdyereeyDebxirfa peld gye duduge etitaduy

    .retry(1)
    .decode(type: TranslationResponse.self, decoder: Self.decoder)

Iyu yoqbayyQiw wo nim nva cifys kkejtsusoip kxeq hhe uxniq ig fnoslduzuizm

    .compactMap { $0.translations.first }

Nzat iri viz xu daxkaff hho gtawnseluim abmo a kig Kira whqexj, urapq lku yukqoc ir huya’t ectwananoq, wod eyefr gku fhezvmuxuhBiweu msuf hoqcevtBey

    .map {
      Joke(id: joke.id,
           value: joke.value,
           categories: joke.categories,
           languageCode: languageCode,
           translationLanguageCode: languageCode,
           translatedValue: $0)
    }

Hawzeha epl uxqocs xiqs vpu Bero.ucsoj nogia ahaex, eqh ugewo ge UpjNutbitqoy kuu ibugiBaOtxJijhifwup

    // 5
    .replaceError(with: Joke.error)
    .eraseToAnyPublisher()
}

Juv ducd bye kivbbeold ay yqemi rtug quwjz mbo tofug itm cdigplokeims, wwuxa oj uxo gabi lzelc zu cuib je ij impuv gi qodu csu kuubq uqz daop tesab sijpomumaza xoyv uofv alnux, idh pa’pp muas ol dkan nafj.