Compartilhando Código com Kotlin Multiplataforma

Apresentada no Kotlin Community Summit 2018

Transcript

1. KOTLIN
   Compartilhando código com Kotlin Multiplataforma
   

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2. ADOTE
   

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3. https://pusher.com/state-of-kotlin
   

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4. Plataformas
   4
   JVM JS NATIVE
   ANDROID
   

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5. Por que usar Kotlin no desenvolvimento Android?
   ● Compatibilidade - Java 6
   ● Performance
   ● Interoperabilidade
   ● Footprint: standard library & runtime ~100Kb
   ● Tempo de Compilação não é mais um problema
   ● Tooling evoluindo
   5
   

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6. https://bit.ly/2ATKly0
   

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7. Por que usar Kotlin no desenvolvimento para JVM?
   ● Expressividade
   ● Escalabilidade & Performance - Kotlin Coroutines
   ● Interoperabilidade com código já existente - migração gradual
   ● Tooling
   7
   

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8. https://bit.ly/2jV4utA
   

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9. JavaFX Framework for Kotlin
   https://github.com/edvin/tornadofx
   

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10. Ktor for building servers and clients
    https://ktor.io
    

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11. Por que usar Kotlin no desenvolvimento JavaScript?
    ● JavaScript Optimized - DCE (Dead Code Elimination)
    ● JavaScript legível e depurável
    ● Compatibilidade com código JavaScript pré-existente
    ● Mesmas features da Standard Library da JVM - incluindo Coroutines
    11
    

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12. https://github.com/JetBrains/kotlin-wrappers
    

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13. Kotlin para JavaScript - e a tipagem?
    ● É possível interagir com qualquer tipo de código JavaScript
    ● Strong-typed APIs / TypeScript -> https://github.com/kotlin/ts2kt
    ● Dynamic types para outros cenários
    13
    

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14. KotlinJS - jQuery
    fun main(args: Array) {
    jq("#message").html("Hello from Kotlin")
    }
    14
    

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15. KotlinJS - React
    class HelloComponent: RComponent() {
    override fun RBuilder.render() {
    div(classes = "content") {
    h1 {
    +"Hello!"
    }
    }
    }
    }
    fun RBuilder.hello() = child(HelloComponent::class) { }
    15
    

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16. KotlinJS - NodeJS
    fun main(args: Array) {
    val express = require("express")
    val app = express()
    app.get("/", { req, res ->
    res.type("text/plain")
    res.send("i am a beautiful butterfly")
    })
    app.listen(3000, {
    println("Listening on port 3000")
    })
    } 16
    

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17. Why to use Kotlin for native development?
    ● Código Nativo
    ● Backend baseado no LLVM
    ● Interoperabilidade com código nativo e bibliotecas - binding gerado a
    partir de arquivos .h
    ● MacOS / iOS - Objective C e Swift
    ● Atualmente na versão 0.9 - em desenvolvimento - 1.3
    17
    

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18. Kotlin Native supported targets
    ● Windows (x86_64)
    ● Linux (x86_64, arm32, MIPS e MIPS little endian)
    ● MacOS (x86_64)
    ● iOS (arm32, arm64, x64)
    ● Android (arm32 e arm64)
    ● STM32
    ● WebAssembly (wasm32)
    18
    

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19. Kotlin Native - C interop
    components.main {
    targets = ['macos_x64', 'linux_x64']
    dependencies {
    cinterop('libcurl-interop') {
    defFile 'src/main/c_interop/libcurl.def'
    target('linux_x64') {
    includeDirs.headerFilterOnly '/usr/include'
    }
    target('macos_x64') {
    includeDirs.headerFilterOnly '/opt/local/include', '/usr/local/include'
    }
    }
    } 19
    

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20. Kotlin Native - C interop
    headers = curl/curl.h
    headerFilter = curl/*
    linkerOpts.osx = -L/opt/local/lib -L/usr/local/opt/curl/lib -lcurl
    linkerOpts.linux = -L/usr/lib64 -L/usr/lib/x86_64-linux-gnu -lcurl
    20
    

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21. Kotlin Native - C interop
    fun fetch() {
    val res = curl_easy_perform(curl)
    if (res != CURLE_OK)
    println("curl_easy_perform() failed")
    }
    fun CPointer.toKString(length: Int): String {
    val bytes = this.readBytes(length)
    return bytes.stringFromUtf8()
    }
    21
    

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22. Integração com IDE
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23. Reference links
    https://kotlinlang.org/docs/reference/android-overview.html
    https://kotlinlang.org/docs/reference/server-overview.html
    https://kotlinlang.org/docs/reference/js-overview.html
    https://kotlinlang.org/docs/reference/native-overview.html
    23
    

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24. MÓDULOS
    MULTIPLATAFORMA
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25. Kotlin Multiplataforma
    ● Suporte introduzido na versão 1.2
    ● JVM & JavaScript (Native "meio que" funciona)
    ● módulos common, platform e regular
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26. Módulos Multiplataforma
    common: Contém código que não é específico a nenhuma plataforma, assim
    como a declaração de APIs que necessitam de implementação específica
    platform: Contém a implementação das APIs definidas em um módulo
    common, além de outros códigos específicos da plataforma
    regular: Módulo comum que tem como target uma plataforma específica
    26
    

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27. Multiplatform Module - Gradle
    buildscript {
    ext.kotlin_version = '1.2.70'
    repositories {
    mavenCentral()
    }
    dependencies {
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
    }
    apply plugin: 'kotlin-platform-common'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-common:$kotlin_version"
    testCompile "org.jetbrains.kotlin:kotlin-test-common:$kotlin_version"
    } 27
    

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28. Multiplatform Module - Gradle
    buildscript {
    ext.kotlin_version = '1.2.70'
    repositories {
    mavenCentral()
    }
    dependencies {
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
    }
    apply plugin: 'kotlin-platform-common'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-common:$kotlin_version"
    testCompile "org.jetbrains.kotlin:kotlin-test-common:$kotlin_version"
    } 28
    

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29. Multiplatform Module - JVM target
    ...
    apply plugin: 'kotlin-platform-jvm'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    expectedBy project(":common")
    testCompile "junit:junit:4.12"
    testCompile "org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version"
    testCompile "org.jetbrains.kotlin:kotlin-test:$kotlin_version"
    }
    29
    

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30. Multiplatform Module - JVM target
    ...
    apply plugin: 'kotlin-platform-jvm'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    expectedBy project(":common")
    testCompile "junit:junit:4.12"
    testCompile "org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version"
    testCompile "org.jetbrains.kotlin:kotlin-test:$kotlin_version"
    }
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31. Multiplatform Module - JavaScript target
    ...
    apply plugin: 'kotlin-platform-js'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-js:$kotlin_version"
    expectedBy project(":common")
    testCompile "org.jetbrains.kotlin:kotlin-test-js:$kotlin_version"
    }
    31
    

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32. Multiplatform Module - JavaScript target
    ...
    apply plugin: 'kotlin-platform-js'
    repositories {
    mavenCentral()
    }
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-js:$kotlin_version"
    expectedBy project(":common")
    testCompile "org.jetbrains.kotlin:kotlin-test-js:$kotlin_version"
    }
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33. Multiplatform Module - Native target
    ...
    buildscript {
    repositories {
    maven { url 'https://jetbrains.bintray.com/kotlin-native-dependencies' }
    }
    dependencies {
    classpath 'org.jetbrains.kotlin:kotlin-native-gradle-plugin:0.8.2'
    }
    }
    apply plugin: 'kotlin-platform-native'
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    expectedBy project(":common")
    }
    ... 33
    

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34. Multiplatform Module - Native target
    ...
    apply plugin: 'kotlin-platform-native'
    dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    expectedBy project(":common")
    }
    sourcesets.main.component {
    baseName.set('MyCommonModule')
    target 'ios_arm64', 'ios_x64'
    outputKinds = [ FRAMEWORK ]
    }
    ...
    34
    

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35. Multiplatform Module - Common code
    package com.example.foo
    expect class Foo(bar: String) {
    fun frob()
    }
    fun main(args: Array) {
    Foo("Hello").frob()
    }
    35
    

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36. Multiplatform Module - JVM implementation
    package com.example.foo
    actual class Foo actual constructor(val bar: String) {
    actual fun frob() {
    println("Frobbing the $bar")
    }
    }
    36
    

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37. DI Multiplataforma
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38. Mock Multiplataforma
    38
    

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39. KOTLIN GRADLE DSL
    Bonus - por que não usar em todo o projeto então?
    

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40. Por que usar a Kotlin Gradle DSL?
    ● Aumento na velocidade de análise e compilação
    dos build scripts, em comparação com Groovy
    ● IDE friendly, melhor autocomplete
    ● Unificação da linguagem de desenvolvimento
    ● 1.0 RC 6 incluído no Gradle 4.10.1, estável no
    Gradle 5.0 (próxima versão)
    40
    

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41. Gradle - Groovy (default)
    // build.gradle
    allprojects {
    buildscript {
    ext.kotlin_version = '1.2.70'
    repositories {
    mavenCentral()
    }
    dependencies {
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
    }
    repositories {
    mavenLocal()
    }
    }
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42. Gradle - Kotlin DSL
    // build.gradle.kts
    allprojects {
    buildscript {
    val kotlin_version by extra { "1.2.70" }
    repositories {
    mavenCentral()
    }
    dependencies {
    classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version")
    }
    }
    repositories {
    mavenLocal()
    }
    }
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43. e se...
    43
    

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44. a gente tivesse um projeto definitivamente full stack em
    Kotlin?
    44
    

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46. 46
    https://github.com/JetBrains/kotlinconf-app
    Ktor / ReactJS / Android / iOS
    

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47. 47
    https://github.com/MarcinMoskala/KotlinAcademyApp
    Ktor / ReactJS / Android / iOS / JavaFX
    

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48. Links
    BLOG OFICIAL
    https://blog.jetbrains.com/kotlin
    KOTLIN KOANS
    https://kotlinlang.org/docs/tutorials/koans.html
    KOTLIN IN ACTION
    https://www.manning.com/books/kotlin-in-action
    48
    

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49. OBRIGADO!
    Questions and feedbacks?
    Rafael Toledo
    rdtoledo@thoughtworks.com
    speakerdeck.com/rafaeltoledo
    github.com/rafaeltoledo
    49
    

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