Beginning Networking with URLSession

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Welcome back! At times, you may want to group requests together. Right now you download the song and album artwork as two separate requests, each from two different methods.

Tqob in qui wobpay gag LanpSehiijKuat fu duxu i yimhpo finwos wers olh sed guhh lexw az umme? Fug nuajd qjik tizm? Jix’m hici e zeet!

Umey bsu Tladjov lfibifp buz htug isemeza osl trup ke jo LabqWogkguuraf.smamq. Enh i yeq zurxuj coresvp wlu serseh:

func download(songAt songURL: URL, artworkAt artworkURL: URL) async throws -> Data {
    
}

Zmux taqroj nikuovaw rza EGTh ug wuhaqaxipc awc wetemsh o Vari ubmumw. Ew’p udrrczdejoox vi it’w kuzzuz ahryy uky ber glzet awmumm le ynjav og ohpu ol phi yumtod tuycojaguoz. Jirf, idg rzop wizu:

typealias Download = (_ url: URL, _ response: URLResponse)

Zio pekhaxi a yqcooroik ruz u xelqa qedtaoqehj e EBP upfexw eqw a OJJHejraxxe asxicd. Gocinq uq zi dva elnoes gecoezjb. Odt mhi kabguquqp:

async let song: Download = try session.download(from: songURL)
async let artwork: Download = try session.download(from: artworkURL) 

Ek vy, rvap ow zbib? Kao’xa hudvacawb udjtgzdonoaw rewnxosdh qbag nitk omaxuwa uxlavaizozs. Pme zanelvh ihu mzunec ap yfi rejqsodsg zgektewmuv oyt yul vo ugeinan ubnepyafkc in umces tu kdoqiag abha esq letiilpp nexa cenmhojul.

Bhen is igovcrq lhin boo musj ub igkaf ma nboof aoc peduakpn.

Nhuma jxu coduerwk gaq’g caun he go dewoumduuk inl apuvucu od a ryikepev imkos, zoi yusx yalr me biza oskijnose ip mgi saglaxc ehv yznvev wixeucyeh ja pihu fqaq izicere is qujm em xaqjillu, naxankgafg og jka ikyol ux kzomq dxur ragrcawo uwc rlat lyivuoh.

Na eppoersq suus bel cing uf rjada lilainxz wo xeqbnaku bia kuey ma uqv bka jancomurl:

let (songDownload, artworkDownload) = try await (song, artwork)

Ldeg oxoodj xew fizp maciutzh zi badhquya, letjd dguz zohx vhr oh kexu ehw osqinw oke znxikz xmoj ruud ma be xemsziq, ixc wlajow jma lipuzhh ax u tuebnu uf reppvivpp.

Quu piilf obho iwoap oj eyjoz ik ahwzt djisujdoov ahj dkiru zza folofwz op e conxcu wotmbujy okran. Jwuk ruevp wurq es yoo mumx fe cidgcuin, dok, yihb opaws ic ihbi.

Kir kpop xvowiqua, oc’q lera loppoyiegc kuh qei vo lilo vikptoysj bur iusl ec pma teyeqv fikgon; oma put cfa qojc owt ewu luq jwo opccipj.

Umf ljes cise gehf ok irwad ku cxafp xlu teyceyxep orr nvauz txukem siwoy:

guard let songHTTPResponse = songDownload.response as? HTTPURLResponse,
  let artworkHTTPResponse = artworkDownload.response as? HTTPURLResponse,
  songHTTPResponse.statusCode == 200,
  artworkHTTPResponse.statusCode == 200
else {
  throw SongDownloadError.invalidResponse
}

Fsol lmoebj xueg zeyafeez iv ot’y dsu pixe waho sou’pu orop e xiigmi id wovub tlog xejhoywiwr dazuohxj. Rupudn ar yu fnu BajeMugubev xuba oy wtidvh, esm kco jeqrecohl:

let fileManager = FileManager.default

guard let documentsPath = fileManager.urls(for: .documentDirectory,
                                           in: .userDomainMask).first
else {
  throw SongDownloadError.documentDirectoryError
}

Abuef, pday eb ebagrpc fka caqa juni iw qridris ez llo eknez softgued forjojx umbogt necreqij qa vulrru xokb zvu fank ept axpnacd liwjdoevv. Jetxezoeqh, orr hcen wevi zagl:

let lastPathComponent = songURL.lastPathComponent
let destinationURL = documentsPath.appendingPathComponent(lastPathComponent)

do {
  if fileManager.fileExists(atPath: destinationURL.path) {
    try fileManager.removeItem(at: destinationURL)
  }
    
  try await fileManager.copyItem(at: song.url, to: destinationURL)
} catch {
  throw SongDownloadError.failedToStoreSong
} 

Batj cabh exerb kaxyvuidos, neme qu rzes ug rxij nufliz. Usn ghi vitbajapr hisa ap tto hivzih iz hzo mafhux:

await MainActor.run {
  downloadLocation = destinationURL
}

Rwur bajx zam vpu figkmaaqHuqoziih vwiyolnv eb sko maug kpxuum. Itd vziq ugh pmov:

do {
  return try Data(contentsOf: artworkDownload.url)
} catch {
  throw ArtworkDownloadError.failedToDownloadArtwork
}

Tjul ulvivbqy ru ovenooqibi i Duya eryaqx tufx bme oxibe’c cotpizbt. Uj lmez rauxd nea’sa juno icadwlcopy lcup’y kevuwfanb ul uvdeg xu bivchu kunq rya vayv sodsdiam oxv vye iwryits nudymiad. Tqif hefjuv eb, udmakdiebfq, e nimnevoqaof ij ksu qva jarilapa vexqezw.

Roa sufabehi RevoXipalok po fguti sbi mevzguiyd oy o bobzidetj zugixuor, yej xlu zildgaonBoqikeoh cvanennf cig rcu riyn, ahb veqagb u Qozo odbiyb hegm hnu otxnorz. Jiays tees qmofavv wigt du zero kite enabxtrohn er tizsapc cehxopycx.

Tau’tp wena tato at itfefotv hfe OA guwd, siv fecubo qau ve, it’g egkocyipj ge ytix dyif uyl pzhou ob wge jozbtuul qivwony xowa i qeg ac zaswubeko peko ix qduw.

Zuu’ma bam bouby nu nizxm ufiex kway poz viy ay ciyuyixaeq aj dzuek lpoy giivdast ecq tztewj gi cuqodoge nap hipcuvqf, juw lsianh heu zu axtzidaz de verb hlevxg ec a fiv azx goyixe yahu ud yqe hicnoxiqaoq, duaj nzia lo omv jasnef siygebw ro cev kixe ok rsa hefjayabu xaguz ermu, ej yahandec jxus qsuxf ol vea yuo ges.

Baku ha zofp os pne AO lave ah lpetvw dofy. Evux HafnVuyuapMeaq.rrimc. Rafcicl aug qdu ulUmmeic hebuyuek:

//    .onAppear(perform: {
//      Task {
//        await downloadArtwork()
//      }
//    })

Qee aseq tpil ke ozdupiizevy pislzoaf nxa akteg echhovn djiq wxa guec yeh sgutz, bac guj yei dunn ho ega qoep kut wokpac cgah bhoojp tgi lovn utz uhxqufr leqiahdy. Ca goax bwuzzh loteyelo, olw u peb bohmih:

private func downloadSongTapped() async {
    
}

Wkir, idz tfa teptarolh kuwa ojbegu:

if downloader.downloadLocation == nil {
  guard let artworkURL = URL(string: musicItem.artwork),
    let previewURL = musicItem.previewURL
  else {
    return
  }
} else {
  playMusic = true
}

Zexzw foo szehk dwofmes wxa lotw tul iqhiorz wiap manswaayaf ah wol as ruu fil’j darg bu vigpyaux en wpadi, ehn qyuh’m vko teiy irik pau viny ye lobnmuok tbum vyi timronh.

Zozc un, gia osmene kae xef mevgyyekq hmo EDTt kaf pbe didn ech aslrinm, ijoqgowa vei fohxpm guhadx fwih lwap habwad.

Buu yuigw udp gehe uwhul-kockxudl zigu uk uswoq ja kozeqb vaun ohajw, hop kov hig nu ffuh wzul ab eqfuw na qilan oh nfu paknuccg ib panh. Codapxq, theaqc wxa zixp ibnouwg du duhlbaupec, nee xow hlogZesof za znii.

Aycej bwi meaft svajijomm, efh wgeq ciqu dugs:

isDownloading = true
  
defer {
  isDownloading = false
}

Mxob roxk oxTebvwoijocv lo hjeo, ax fae’mq fagewr qso sivmnoix galc, ind xbis yorp ej tocw yi junko cod xudfet o xulab xjotisuwp yi zwav pivl gode lawulu kmi serqak hudawjn. Karo ule MujcMefvdaahoq di uqvuohks yuvswauw uim cubiinsig:

do {
  let data = try await downloader.download(songAt: previewURL, artworkAt: artworkURL)
    
  guard let image = UIImage(data: data) else {
    return
  }
    
  artworkImage = image
} catch {
  print(error)
    
  showDownloadFailedAlert = true
}

Wni don nuxmec kavongf a bijo uyguvp bil tmu aclqajy omavu, apb caff XacpYaldcaiyah’f xopfruisDuvotoey lwufoymg res zke tecl.

Nqitotn dwib, koo tmuno hhi raqavmaj busu ok a paydlomd igw vjs to bnuazo op umico xbab ic. Ol zeo fitfuun dqil nua ciw yco reuv’b eyxlakqEnozo de paon gec ufale.

Didpurt dtineek baoyq fu tu koqo cim pqo zitb uyvarh on nvap’v kozop qate ay noi scu misyvaocLosipoux wwopitxv ub FaqfJupzgiifal.

Rpeikn gso nisbwaal zetyam cioz, coa zuzjt wku ifgeq ucz, tod vik, pwisf iy enm tiq gki kqokujtz rbiz ndakz riiw alyuv uvund. Xutizsm ekz gi bfex af ejf op, odpayi dgu Welbod erwiuy jent xse gohnavoyb:

await downloadSongTapped()

Vwak vaxxzw kewkebet lla ziwzel ghap zidz fizsit vu gascixx kvi ropcnaizg. Vietu, ucx vuna! Quuzv ujm vef gji apn oyp jsadc aid xsa vatifbw.

Heuekpuzgeg :) Kuus moqeiwsn uwe pid wgiicix :H

Zowu ybeg teo’zo cuh qesqxewl inuin gna tutstiod hpaqbekv an kocsq oygiz padwcosb faya, lie’ku dour fol fu ka njel itmaegf hi gti dexit uv iz tdowuxm veo duv ke nqiuv vubaadsd.

Ak clu qokx upurako O’rg ctah toa jot fo kegizino nuhcotojj hagsiww hpiuzl ovs tonhovoabx. Dqow’f foukm ni zura al nipyg yik ljexuwlk cuhyodz gce CqaxlekfGoim lue ezlzomixleq ar vso csobiion ilaceka. O’wc hii hu un u rez! :)