Getting started with Kotlin/Native in a project near you

Given at an internal company event.

Want to getting started with Kotlin/Native in your Android and iOS TODAY?
Fine, let's do it.
In this talk I present how to setup everything so that we can start coding on a shared library for both platforms.

Transcript

1. Getting started with
   Kotlin/Native
   in a project near you
   

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2. Kotlin/Native
   Kotlin/Multiplatform
   

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4. Kotlin + /JVM + /Native + /JS
   =
   Kotlin/Multiplatform
   

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5. Kotlin + /JVM + /Native + /JS
   =
   Kotlin/Multiplatform
   

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7. We have a problem
   in the Kotlin/Multiplatform docs
   

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8. .
   ├── SharedCode
   │ └── src
   │ ├── commonMain
   │ ├── androidMain
   │ └── iosMain
   ├── android
   │ └── src
   │ ├── main
   │ ├── test
   │ └── androidTest
   ├── native
   │ └── KotlinIOS
   │ ├── KotlinIOS
   │ ├── KotlinIOSTests
   │ └── KotlinIOSUITests
   └── ...
   Taken from
   github.com/kotlin-hands-on/mpp-ios-android
   

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9. someProjectRepo
   /iOS
   someProjectRepo
   /Android
   

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10. someProjectRepo
    /iOS
    someProjectRepo
    /Android
    someProjectRepo
    /mobile
    

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11. someProjectRepo
    /iOS
    someProjectRepo
    /Android
    someProjectRepo
    /mobile
    

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13. What if…
    

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14. an independent project creates artifacts
    (Jar & Framework)
    

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15. which can be published
    

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16. and imported in our existing projects
    // Gradle (Android)
    repositories {
    maven(url = "https://artifactory.some.thing")
    }
    dependencies {
    implementation("something:sharedLib:1.0.0")
    }
    // Carthage (iOS)
    binary "https://artifactory.some.thing/something/sharedLib.json" ~> 1.0.0
    

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18. iOS devs...
    welcome to the world of Gradle
    

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19. plugins {
    kotlin("multiplatform") version "1.3.50"
    }
    kotlin {
    jvm()
    // This is for real iDevices
    iosArm64().binaries.framework()
    // This is for simulators
    iosX64().binaries.framework()
    }
    repositories {
    jcenter()
    }
    val jvmMainImplementation by configurations
    dependencies {
    commonMainImplementation(kotlin("stdlib-common"))
    jvmMainImplementation(kotlin("stdlib-jdk8"))
    }
    

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20. That's it
    Happy coding y'all
    

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21. Uhm.. sorry.
    But you said something about
    artifacts and publishing
    

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22. Build tasks
    -----------
    - jvmJar
    - linkDebugFrameworkIosArm64
    - linkDebugFrameworkIosX64
    - linkReleaseFrameworkIosArm64
    - linkReleaseFrameworkIosX64
    Artifacts - Jar and Framework
    ./gradlew tasks
    

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23. pluginManager.apply("maven-publish")
    // Setup our artifactory repository
    extensions.getByType(PublishingExtension::class.java).apply {
    repositories { repoHandler ->
    repoHandler.maven {
    it.name = "Artifactory"
    it.url = project.uri("https://artifactory.some.thing/something")
    it.credentials { credentials ->
    credentials.username = properties["artifactoryUser"] as? String
    credentials.password = properties["artifactoryKey"] as? String
    }
    }
    }
    }
    Publishing - Jar
    

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24. // Creates a task to pack the `iosArm64` & `iosX64` Frameworks
    // into one Framework.
    // This is because the Simulator and Devices running on different platforms.
    // Therefore we need a Framework which runs on both.
    val fatFrameworkTask = tasks.register("releaseFatFramework", FatFrameworkTask::class) {
    …
    }
    // Well, it's complicated!
    Publishing - Framework
    

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25. We are using Carthage as a…
    "dependency manager"*
    *Seems only Gradle users get this joke
    

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26. FatFramework
    kotlin {
    iosArm64().binaries.framework {
    baseName = "sharedLib"
    }
    iosX64().binaries.framework {
    baseName = "sharedLib"
    }
    }
    val fatFrameworkTask = tasks.register("releaseFatFramework", FatFrameworkTask::class) {
    baseName = "sharedLib"
    from(
    kotlin.iosArm64().binaries.getFramework("RELEASE"),
    kotlin.iosX64().binaries.getFramework("RELEASE")
    )
    }
    

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27. ...Zipp it and publish
    val zipFramework = tasks.register("zipFatFramework", Zip::class.java) {
    it.dependsOn(tasks.named("releaseFatFramework"))
    it.from("$buildDir/fat-framework")
    it.archiveFileName.set("sharedLib.framework.zip")
    it.destinationDirectory.set(file("$buildDir/fat-framework-zip"))
    }
    tasks.register("publishFatFrameworkToArtifactory", Exec::class.java) {
    it.dependsOn(tasks.named("releaseFatFramework"), zipFramework)
    it.commandLine("jfrog", "magic")
    }
    

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28. Create a JSON file for "versioning"
    /**
    * // The code should generate something like this:
    * ```
    * {
    * "1.0.0": "https://artifactory.some.thing/1.0.0/shared.Framework.zip",
    * "1.0.1": "https://artifactory.some.thing/1.0.1/shared.Framework.zip",
    * "1.1.0": "https://artifactory.some.thing/1.1.0/shared.Framework.zip"
    * }
    * ```
    * Basically a `version <-> Framework location` mapping.
    */
    

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29. ...and publish it as well
    tasks.register("publishFrameworkJsonToArtifactory", Exec::class.java) {
    it.dependsOn(downloadAndModifyJson)
    it.commandLine("jfrog", "magic")
    }
    

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31. Q'nd A
    

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