Fars\u00edmi? Vefur? M\u00e9r er sama.<\/h2>\n
Segjum a\u00f0 vi\u00f0 viljum b\u00faa til forrit sem notar React<\/a> b\u00f3kasafn. \u00deetta b\u00f3kasafn m\u00e1 nota til a\u00f0 byggja vef- og fars\u00edmaforrit me\u00f0 React native. R\u00f6kr\u00e6nar v\u00e9lb\u00fana\u00f0arh\u00e6tti forritsins, svo sem heimildaveitingu, \u00fatreikninga og s\u00edun. g\u00f6gn<\/a> og svo framvegis, er h\u00e6gt a\u00f0 gera me\u00f0 React-kr\u00f3kum. Meginatri\u00f0i\u00f0 er a\u00f0 \u00feessir kr\u00f3kar geta veri\u00f0 sameiginlegir b\u00e1\u00f0um \u00fatg\u00e1fum forritsins \u2013 vef- og fars\u00edma\u00fatg\u00e1fu. \u00de\u00f6kk s\u00e9 \u00feessari valkostum h\u00f6fum vi\u00f0 eftirfarandi vistanir:<\/p>\n Til a\u00f0 draga \u00feennan m\u00e1lsgrein saman \u2013 \u00fea\u00f0 er ekki \u00feannig a\u00f0 ein k\u00f3\u00f0agrunnur muni kn\u00fdja allar \u00fatg\u00e1fur forritsins, \u00fe\u00f3 a\u00f0 vi\u00f0 getum skipt sameiginlega k\u00f3\u00f0anum og nota\u00f0 hann \u00ed hverri \u00feeirra til a\u00f0 gera \u00fer\u00f3unarferli<\/a> Miki\u00f0 hra\u00f0ar.<\/p>\n \u00c1lyktun \u2013 ef \u00fe\u00fa vilt byggja vef- og fars\u00edmaforrit samt\u00edmis, \u00edhuga\u00f0u React-b\u00f3kasafni\u00f0 sem getur deilt k\u00f3\u00f0agrunni \u00ed fars\u00edma- og vef\u00fatg\u00e1fu forritsins.<\/p>\n Fyrir nokkrum \u00e1rum, \u00feegar r\u00e6tt var um bakendann, myndu f\u00e1ir hafa \u00edmynda\u00f0 s\u00e9r a\u00f0 vi\u00f0hald hans g\u00e6ti veri\u00f0 m\u00f6gulegt me\u00f0 hj\u00e1lp tungum\u00e1ls eins og JS<\/strong>. \u00der\u00f3un \u00feessa tungum\u00e1ls er \u00f3tr\u00faleg og \u00e1v\u00f6xtum \u00feess m\u00e1 enn n\u00fdta \u00ed dag.<\/p>\n Um hva\u00f0 er \u00e9g a\u00f0 tala? Ef \u00fe\u00fa r\u00e6\u00f0ur r\u00e9ttan JS-\u00fer\u00f3unara\u00f0ilar<\/strong>, kemur \u00ed lj\u00f3s a\u00f0 \u00feeir geta skrifa\u00f0 ekki a\u00f0eins frontend-i\u00f0 \u00ed forritinu, heldur einnig backend-i\u00f0 \u2013 \u00fea\u00f0 er a\u00f0 segja, s\u00e9\u00f0 um vinnslu gagna \u00e1 net\u00fej\u00f3ninum, samskipti vi\u00f0 gagnagrunninn, \u00fdmsar tegundir sam\u00fe\u00e6ttinga o.s.frv. Enn hikandi e\u00f0a ekki sannf\u00e6r\u00f0ur um \u00feetta forritunarm\u00e1l? \u00dea\u00f0 er engin \u00e1st\u00e6\u00f0a til a\u00f0 hafa sl\u00edka afst\u00f6\u00f0u! Backend me\u00f0 JS <\/strong> m\u00e1 innlei\u00f0a \u00e1 tvo vins\u00e6la vegu \u2013 \u00ed framl\u00e6gjanlegu og stillanlegu formi sem express.js getur veitt okkur, og \u00ed uppbygg\u00f0u formi me\u00f0 DI-mynstri \u2013 nest.js.<\/p>\n B\u00e1\u00f0ar lausnirnar eru \u00e1kaflega vins\u00e6lar og kn\u00fdja fram fj\u00f6lda framlei\u00f0sluums\u00f3kna sem eigendur \u00feeirra eru t\u00e6knirisar \u00ed s\u00ednum i\u00f0na\u00f0i. \u00c9g tel a\u00f0 \u00fe\u00e6r hafi \u00feroskast n\u00e6gilega til a\u00f0 sannf\u00e6ra \u00feig um a\u00f0 velja hvorri sem er \u00feeirra.<\/p>\n Ekki n\u00f3g enn\u00fe\u00e1? L\u00edkt og k\u00f3\u00f0ahlutdeild milli vef- og fars\u00edmaforrita getur bakendinn deilt au\u00f0lindum me\u00f0 b\u00e1\u00f0um. Lykilor\u00f0i\u00f0 sem \u00e1 a\u00f0 nota h\u00e9r er TypeScript<\/a> \u2013 me\u00f0al annars gerir \u00fea\u00f0 okkur kleift a\u00f0 deila k\u00f3\u00f0agrunni, \u00fe.e. sameiginlegri skilgreiningu \u00e1 gagnategundum \u00e1 \u00f6llum vettvangi.<\/p>\n Me\u00f0 forritum sem eru eing\u00f6ngu bygg\u00f0 \u00e1 JavaScript<\/a> <\/strong>\/ TypeScript<\/strong> Me\u00f0 \u00fev\u00ed a\u00f0 nota mon\u00f3l\u00edt\u00edska n\u00e1lgun sparast okkur margar k\u00f3\u00f0al\u00ednur sem vi\u00f0 \u00feyrftum a\u00f0 endurtaka \u00ed hef\u00f0bundnum forritunarm\u00e1lum. \u00c1 hinn b\u00f3ginn, me\u00f0 \u00fev\u00ed a\u00f0 nota sama forritunarm\u00e1li\u00f0 \u00e1 \u00f6llum svi\u00f0um getum vi\u00f0 deilt gr\u00ed\u00f0arlegu magni af r\u00f6kv\u00edsi \u00e1 milli allra forrita, sem myndi \u00e1n efa fl\u00fdta fyrir \u00feeim t\u00edma sem fer \u00ed a\u00f0 byggja upp tilteki\u00f0 forrit. Hlj\u00f3mar \u00fea\u00f0 ekki fr\u00e1b\u00e6rlega?<\/p>\n \u00dea\u00f0 kemur \u00ed lj\u00f3s a\u00f0 t\u00e6kni til a\u00f0 b\u00faa til vafraforrit hentar einstaklega vel til a\u00f0 vi\u00f0halda \u00feeim forritum sem vi\u00f0 notum \u00ed skj\u00e1bor\u00f0s\u00fatg\u00e1fu \u2013 gott d\u00e6mi um \u00feetta er Slack. Slack er forrit sem er nota\u00f0 til a\u00f0 li\u00f0<\/a> Samskipti \u2013 umfram hef\u00f0bundna skilabo\u00f0asendingu b\u00fd\u00f0ur \u00fea\u00f0 upp \u00e1 fj\u00f6lmargar a\u00f0ger\u00f0ir og \u00fdmsar tegundir af ytri sam\u00fe\u00e6ttingum. Allt \u00feetta gerir \u00fea\u00f0 a\u00f0 einni vins\u00e6lustu forritunum sem notu\u00f0 eru a\u00f0allega \u00ed uppl\u00fdsingat\u00e6knigeiranum.<\/p>\n Svo sem kemur \u00ed lj\u00f3s notar Slack einnig vef\u00adt\u00e6kni (og \u00fear me\u00f0 JavaScript) til a\u00f0 byggja forritavi\u00f0m\u00f3t sitt. Grunnurinn sem gerir \u00fea\u00f0 m\u00f6gulegt a\u00f0 keyra sl\u00edk forrit \u00e1 skj\u00e1bor\u00f0inu \u00fe\u00ednu er Electron. A\u00f0 b\u00faa til graf\u00edsk vi\u00f0m\u00f3t me\u00f0 vef\u00adt\u00e6kni gerir \u00fea\u00f0 mun au\u00f0veldara, hra\u00f0ara og almennt m\u00f6gulegt a\u00f0 \u00fer\u00f3a forrit fyrir mismunandi vettvanga samt\u00edmis.<\/p>\n \u00dat fr\u00e1 framenda hluta forritsins er engin blekking um a\u00f0 JS <\/strong>er eina og eina tungum\u00e1li\u00f0 sem kn\u00fdr vistkerfi\u00f0 h\u00e9r \u00e1fram. A\u00f0 svo st\u00f6ddu eru engar raunh\u00e6far lausnir sem geta komi\u00f0 \u00ed sta\u00f0 \u00feessa hluta forritsins (\u00fe\u00f3 \u00e9g telji a\u00f0 WebAssembly g\u00e6ti komi\u00f0 okkur \u00e1 \u00f3vart \u00ed framt\u00ed\u00f0inni). \u00deannig, \u00feegar r\u00e6tt er um \u00feroska JS \u00e1 framenda, er enginn vafi \u00e1 \u00fev\u00ed a\u00f0 \u00fea\u00f0 er eini konungurinn.<\/p>\n \u00deegar r\u00e6tt er um bakendann kunna margir forritarar a\u00f0 vir\u00f0ast hissa e\u00f0a neita strax a\u00f0 JavaScript henti sem forritunarm\u00e1l \u00e1 bakendanum. Hins vegar \u00fearf a\u00f0 greina m\u00e1li\u00f0 hlutlaust.<\/p>\n Margir sk\u00fdja\u00fej\u00f3nustuveitendur bj\u00f3\u00f0a upp \u00e1 SDK sem gera \u00fe\u00e9r kleift a\u00f0 nota beint sk\u00fd<\/a> a\u00f0fer\u00f0ir. Fur\u00f0ulega n\u00f3g, einn af vins\u00e6lustu flipunum, beint vi\u00f0 hli\u00f0ina \u00e1 C#, Far\u00f0u og Java<\/a>, er Node.js<\/a>. \u00dea\u00f0 kemur \u00ed lj\u00f3s a\u00f0 \u00feetta vettvangur er kj\u00f6rinn til a\u00f0 st\u00e6kka og byggja forrit sem byggja \u00e1 \u00f6r\u00fej\u00f3nustur<\/a> e\u00f0a \u00fej\u00f3nustulausri arkitekt\u00far. Ni\u00f0ursta\u00f0a \u2013 JS er eitt af vins\u00e6lustu forritunarm\u00e1lunum til a\u00f0 \u00fer\u00f3a forrit sem byggja \u00e1 \u00f6r\u00fej\u00f3nustum\/\u00fej\u00f3nustulausri arkitekt\u00far. \u00c1 skj\u00e1myndunum h\u00e9r a\u00f0 ne\u00f0an sj\u00e1um vi\u00f0 a\u00f0 hin heilaga \u00ferenning (Google Computing Services, AWS<\/a>, Bl\u00e1r<\/a>) af sk\u00fdja\u00fej\u00f3nustuveitum gerir okkur kleift a\u00f0 byggja forrit me\u00f0 hn\u00fatur<\/a>.js.<\/p>\n Var\u00f0andi node.js-vistkerfi\u00f0 er l\u00edklega allir kunnugir b\u00f3kasafninu express.js \u2013 einf\u00f6ldu og beinu t\u00f3li sem gerir \u00fe\u00e9r kleift a\u00f0 skilgreina sl\u00f3\u00f0ir og f\u00e6\u00f0a \u00fe\u00e6r vi\u00f0eigandi g\u00f6gnum sem hafa veri\u00f0 r\u00e9tt unnin \u00e1 JavaScript-hli\u00f0inni. Enn fremur hefur mynstri\u00f0 sem nota\u00f0 er \u00ed HTTP-bei\u00f0num \u00ed express.js or\u00f0i\u00f0 eitt vins\u00e6lasta \u00ed \u00f6llu vistkerfinu og er eins konar fyrirmynd fyrir \u00fdmis \u00f6nnur b\u00f3kas\u00f6fn sem n\u00fdta til d\u00e6mis serverless-arkitekt\u00far.<\/p>\n \u00c1lyktun \u2013 JS er forritunarm\u00e1l sem er n\u00e6gilega \u00feroska\u00f0 til a\u00f0 sj\u00e1 um allt og byggja b\u00e6\u00f0i frontend og backend. Auk \u00feess er \u00fea\u00f0 tilt\u00f6lulega n\u00fdtt forritunarm\u00e1l sem finnur au\u00f0veldlega lei\u00f0 s\u00edna inn \u00ed n\u00fat\u00edma forritager\u00f0ararkitekt\u00far. \u00dea\u00f0 er fr\u00e1b\u00e6rt a\u00f0 forritari sem \u00feekkir eitt forritunarm\u00e1l geti n\u00e1\u00f0 t\u00f6kum \u00e1 b\u00e1\u00f0um hli\u00f0um (full stack) forrits.<\/p>\n J\u00e6ja, v\u00e9lin sem oftast er notu\u00f0 til a\u00f0 keyrsa JS-k\u00f3\u00f0a er v8, kn\u00fain af C++-forritunarm\u00e1linu. \u00deessi v\u00e9l, sem Google \u00fer\u00f3a\u00f0i, er h\u00f6nnu\u00f0 til a\u00f0 keyra forrit \u00e1 vefvettvangi. \u00c1hugavert er a\u00f0 \u00feessi v\u00e9l t\u00falkar ekki JS-k\u00f3\u00f0ann. \u00cd sta\u00f0inn framkv\u00e6mir h\u00fan \u00fea\u00f0 sem kallast \u201cJIT\u201d \u2013 \u201cjust in time compilation\u201d. \u00de\u00f6kk s\u00e9 \u00feessu \u00feurfum vi\u00f0 ekki a\u00f0 t\u00falka JS-k\u00f3\u00f0ann l\u00ednu fyrir l\u00ednu, heldur \u00fe\u00fd\u00f0um vi\u00f0 hann og keyrum hann. \u00dea\u00f0 er enn hra\u00f0ara og gefur okkur virkilega g\u00f3\u00f0a frammist\u00f6\u00f0u.<\/p>\n Er JS n\u00e6gilega gott hva\u00f0 var\u00f0ar afk\u00f6st? J\u00e1, \u00fea\u00f0 er \u00fea\u00f0. Svo lengi sem reikniritin \u00fe\u00edn eru n\u00e6gilega g\u00f3\u00f0 er ekkert m\u00e1l a\u00f0 nota JS \u00e1 \u00fej\u00f3nahli\u00f0inni. Anna\u00f0 er a\u00f0 halda k\u00f3\u00f0anum \u00fe\u00ednum eins \u00f3samstilltum og unnt er. Me\u00f0 \u00feessum vinnubr\u00f6g\u00f0um getur k\u00f3\u00f0inn \u00feinn tekist \u00e1 vi\u00f0 samhli\u00f0a bei\u00f0nir \u00e1n vandam\u00e1la. \u00de\u00fa \u00fearft ekki a\u00f0 hafa \u00e1hyggjur af t\u00e6kni\u00adskiptum vegna afkasta \u2013 s\u00e9rstaklega \u00feegar arkitekt\u00far forritsins er skalanlegur.<\/p>\n \u00c9g hef \u00feegar r\u00e6tt frammist\u00f6\u00f0u og vi\u00f0mi\u00f0unarkannanir \u00edtarlega \u00ed \u00feessari grein. <\/p>\n J\u00e6ja, h\u00e9r eru tugir af sko\u00f0unum um a\u00f0 JavaScript-m\u00e1li\u00f0 heg\u00f0i s\u00e9r skr\u00fdti\u00f0 \u00ed sumum tilvikum og a\u00f0 f\u00e1st vi\u00f0 \u00fea\u00f0 getur sprengt hausinn \u00e1 \u00fe\u00e9r \u00e1 \u00fer\u00f3unarferlinu. \u00c9g get ekki veri\u00f0 samm\u00e1la \ud83d\ude42 R\u00e9tt eins og hva\u00f0a anna\u00f0 forritunarm\u00e1l sem er, hefur \u00fea\u00f0 nokkur mynstur og heg\u00f0unarmynstur sem eru ekki f\u00e1gu\u00f0, en me\u00f0 skilningi \u00e1 \u00fev\u00ed hvernig \u00feau virka og hva\u00f0 markmi\u00f0 \u00feeirra eru, er \u00fer\u00f3un forrita me\u00f0 JavaScript alls ekki \u00f3\u00fe\u00e6gileg.<\/p>\n S\u00e9rstaklega or\u00f0i\u00f0 \u201casynchr\u00f3nt\u201d r\u00e9tt \u00e1\u00f0ur en JavaScript kemur f\u00e6r suma forritara til a\u00f0 skj\u00e1lfa. \u00dea\u00f0 er erfitt a\u00f0 skilja \u00feegar ma\u00f0ur hefur enga reynslu af \u00fev\u00ed. Hins vegar er \u00feetta hluti af JavaScript sem gerir okkur kleift a\u00f0 byggja upp n\u00fat\u00edmalegar lausnir \u00e1 au\u00f0veldan h\u00e1tt. Sko\u00f0um vefjasamb\u00f6nd (WebSockets): \u00fear sem \u00feau eru atbur\u00f0adrifin \u2013 hvert tengt eintak, notandinn og net\u00fej\u00f3nninn, getur sent fr\u00e1 s\u00e9r og teki\u00f0 \u00e1 m\u00f3ti atbur\u00f0um samhli\u00f0a. Ef k\u00f3\u00f0inn sem kn\u00fdr \u00feessa forrit er n\u00e6gilega \u00f3samstilltur og hindrar ekki a\u00f0al\u00fer\u00e1\u00f0inn, getum vi\u00f0 au\u00f0veldlega afgreitt \u00fe\u00fasundir bei\u00f0na \u00e1 sk\u00f6mmum t\u00edma.<\/p>\n Samanberum JS og PHP<\/a> \u00cd samhengi vefjasl\u00f3\u00f0a. PHP er samstillt forritunarm\u00e1l, svo a\u00f0 takast \u00e1 vi\u00f0 vefjasl\u00f3\u00f0avi\u00f0fangsefni veldur miklum h\u00f6fu\u00f0verk. Vi\u00f0 sj\u00e1um a\u00f0 PHP s\u00e6kir mynstur \u00far JS til a\u00f0 byggja upp gagnvirkar bakendaums\u00f3knir sem geta n\u00fdtt n\u00fat\u00edmalegar t\u00e6knir, svo sem webrtc e\u00f0a vefjasl\u00f3\u00f0ir.<\/p>\n \u00deegar allir m\u00e1lsgreinar eru settar saman getum vi\u00f0 l\u00fdst nokkrum sta\u00f0reyndum:<\/p>\n JavaScript<\/strong> er forritunarm\u00e1l sem h\u00e6gt er a\u00f0 nota til a\u00f0 b\u00faa til alls konar forrit \u2013 fr\u00e1 vef- og fars\u00edmaforritum til skj\u00e1bor\u00f0sforrita; Til a\u00f0 gefa m\u00edna, j\u00e1, hlutdr\u00e6gu sko\u00f0un \u2013 a\u00f0 n\u00fdta valkost JavaScript um a\u00f0 endurn\u00fdta sama k\u00f3\u00f0ann \u00e1 \u00f6llum tilt\u00e6kum svi\u00f0um mun vissulega fl\u00fdta fyrir forritunar\u00fer\u00f3un og draga \u00far fj\u00f6lda forritara sem \u00feurfa a\u00f0 vi\u00f0halda bakenda forrita skrifa\u00f0ra \u00ed \u00f6\u00f0rum t\u00e6kni. Til sta\u00f0festingar skulum vi\u00f0 rifja upp \u00fe\u00e1 sta\u00f0reynd a\u00f0 gr\u00ed\u00f0arlegur fj\u00f6ldi svokalla\u00f0ra uppl\u00fdsingat\u00e6knirisa fylgir \u00feessu mynstri og deilir t\u00f6luver\u00f0um hluta k\u00f3\u00f0agrunns s\u00edns \u00e1 milli vettvanga. \u00der\u00e1tt fyrir \u00f3l\u00edkar sko\u00f0anir \u00e1 \u00feessu forritunarm\u00e1li ver\u00f0ur \u00fe\u00fa a\u00f0 taka tillit til \u00feess a\u00f0 t\u00f6lfr\u00e6\u00f0i um notkun og \u00e1n\u00e6gju af notkun JS <\/strong>vaxa fr\u00e1 \u00e1ri til \u00e1rs, og forritarar \u00feess geta au\u00f0veldlega tengst full-stack-stefnunni.<\/p>\n Lesa meira:<\/b><\/p>\n Af hverju \u00fe\u00fa \u00e6ttir (l\u00edklega) a\u00f0 nota TypeScript<\/a><\/p>\n Hvernig \u00e1 ekki a\u00f0 drepa verkefni me\u00f0 sl\u00e6mum forritunarvenjum?<\/a><\/p>\n\n
En hva\u00f0 me\u00f0 bakendann?<\/h2>\n
Getur JS kn\u00fai\u00f0 skj\u00e1bor\u00f0sforrit?<\/h2>\n
Er JS n\u00e6gilega \u00feroska\u00f0?<\/h2>\n
![\"Node.js](\"\/app\/uploads\/2024\/05\/zrzut-ekranu-2021-08-24-o-12.13.12.png\" "\\"Skyndibyrjun")
<\/p>\n![\"Samanbur\u00f0ur](\"\/app\/uploads\/2024\/05\/zrzut-ekranu-2021-08-24-o-12.13.25.png\" "\\"Fimm")
<\/p>\nEr JS n\u00f3gu hratt?<\/h2>\n
Er JS ekki svo s\u00e9rkennilegur mi\u00f0a\u00f0 vi\u00f0 a\u00f0rar forritunarm\u00e1l?<\/h2>\n
Blandi\u00f0 \u00f6llu saman<\/h2>\n
\nForrit sem skrifu\u00f0 eru \u00ed JS geta deilt \u00fdmsum k\u00f3\u00f0abrotum s\u00edn \u00e1 milli, svo sem \u00feeim sem sj\u00e1 um gagnaformger\u00f0 e\u00f0a ger\u00f0ir \u00ed Typescript;
\n\u00de\u00f6kk s\u00e9 vexti vefsins er frammista\u00f0a JavaScript n\u00e6gilega g\u00f3\u00f0 til a\u00f0 velja JavaScript b\u00e6\u00f0i fyrir frams\u00ed\u00f0u- og bakenda\u00fer\u00f3un forrita.;
\n\u00de\u00f6kk s\u00e9 \u00f3venjulegri h\u00f6nnun sinni getur JavaScript stutt n\u00fat\u00edma forritainnvi\u00f0i, svo sem WebSockets og WebRTC;
\nMe\u00f0 \u00fev\u00ed a\u00f0 r\u00e1\u00f0a r\u00e9tt h\u00e6fan forritara getur\u00f0u n\u00fdtt m\u00f6guleika \u00feess \u00e1 \u00f6llum tilt\u00e6kum framendavi\u00f0m\u00f3tum sem kn\u00fdja \u00feetta forritunarm\u00e1l;
\nJS er forritunarm\u00e1l sem hefur veri\u00f0 a\u00f0 klifra upp vins\u00e6ldalistana \u00ed nokkur \u00e1r n\u00fana, og ekkert bendir til \u00feess a\u00f0 \u00fea\u00f0 muni breytast \u00e1 nokkurn h\u00e1tt.<\/p>\n![\"R\u00e1\u00f0gj\u00f6f](\"\/app\/uploads\/2024\/05\/cta_2.jpeg\")
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