Migrate Gradle To Kotlin DSL

A presentation about the topic "Migrate Gradle To Kotlin DSL", GDG Tbilisi Android Meetup November 30

Transcript

1. Migrate Gradle To Kotlin DSL Luka Parchukidze 30.11.2021
2. TABLE OF CONTENTS ❖ What is DSL (with examples) ❖ buildSrc Directory ❖ Migrate Project-Module Gradle Files to Kotlin DSL ❖ Control Dependencies Versions ❖ Comparison: Groovy DSL VS Kotlin DSL
3. Introduction
4. What is DSL ? A domain-specific language is a computer language specialized to a particular application domain Generally, DSLs are developed in close coordination with the experts in the field for which the DSL is being designed.
5. Examples of DSLs:
6. Kotlin DSL Gradle’s Kotlin DSL provides an alternative syntax to the traditional Groovy DSL with an enhanced editing experience in supported IDEs, with superior content assist, refactoring, documentation, and more.
7. buildSrc buildSrc is a directory at the Gradle project root, which can contain our build logic.
8. Create our first Kotlin DSL file Create buildSrc directory at the project root and Inside buildSrc create the file build.gradle.kts and enable the kotlin-dsl plugin. import org.gradle.kotlin.dsl.`kotlin-dsl` plugins { `kotlin-dsl` } repositories { google() mavenCentral() }
9. Extract All Gradle Stuff To buildSrc Extract all dependencies, plugins, configs, verions etc. into separated objects. object Versions { const val GRADLE: String = "7.0.3" const val KOTLIN: String = "1.5.31" const val KTX_CORE: String = “1.7.0“ const val RETROFIT2: String = “2.6.2" const val HILT: String = "2.39.1" . . . . . } object Dependencies { const val KTX_CORE: String = "androidx.core:core-ktx:${Versions.KTX_CORE}" const val RETROFIT: String = "com.squareup.retrofit2:retrofit:${Versions.RETROFIT2}" const val HILT: String = "com.google.dagger:hilt-android:${Versions.HILT}“ . . . . . }
10. Extract All Gradle Stuff To buildSrc object Plugins { const val ANDROID_APPLICATION = "com.android.application“ const val KOTLIN_ANDROID = "android“ const val KOTLIN_KAPT = "kapt" const val DAGGER_HILT = "dagger.hilt.android.plugin" const val DETEKT = "io.gitlab.arturbosch.detekt" } object DefaultConfig { const val MIN_SDK = 23 const val TARGET_SDK = 31 const val COMPILE_SDK = 31 }
11. Look at buildSrc in sample project
12. Start migrating project & module gradle files
13. Migration First Steps Change module-project gradle files type (file name extension) to .kts to make all gradle red
14. Migrate Classpathes buildscript { repositories { google() mavenCentral() } dependencies { classpath(Build.BUILD_GRADLE) classpath(Build.KOTLIN_GRADLE_PLUGIN) classpath(Build.DETEKT) classpath(Build.HILT_GRADLE_PLUGIN) } } Kotlin DSL buildscript { repositories { google() mavenCentral() } dependencies { classpath Build.BUILD_GRADLE classpath Build.KOTLIN_GRADLE_PLUGIN classpath Build.DETEKT classpath Build.HILT_GRADLE_PLUGIN } } Groovy DSL project gradle project gradle
15. Project Plugin Expanding Properties Issue Excpected Behaviour Build file 'C:\...\KotlinDSLMeetup\build.gradle' line: 23 Could not compile build file 'C:\...\KotlinDSLMeetup\build.gradle'. > startup failed: build file 'C:\...\KotlinDSLMeetup\build.gradle': 23: argument list must be exactly 1 literal String or String with property replacement Groovy DSL project gradle Reality Gradle Issue: https://github.com/gradle/gradle/issues/1697 plugins { id "io.gitlab.arturbosch.detekt" version Versions.DETEKT or id Plugins.DETEKT version Versions.DETEKT }
16. Project Plugin Expanding Properties Issue Solutions Groovy DSL project gradle buildcript { ext { detekt_version = Versions.DETEKT } } plugins { id "io.gitlab.arturbosch.detekt" version "$detekt_version" } 1. Extract version to gradle.properties ---> detektVersion=1.18.1 2. Extract version to ext (project gradle) Kotlin DSL project gradle plugins { id(Plugins.DETEKT) version Versions.DETEKT }
17. Tasks Declaration Groovy DSL project gradle Kotlin DSL project gradle detekt { tasks.register<io.gitlab.arturbosch.detekt.Detekt>("detektAll") {...} tasks.register<io.gitlab.arturbosch.detekt.DetektCreateBaselineTask> ("detektGenerateProjectBaseline") {...} } detekt { tasks { task detektAll(type: Detekt) {...} task detektGenerateProjectBaseline(type: DetektCreateBaselineTask) {...} } }
18. Migrate Module Gradle Groovy DSL module gradle Kotlin DSL module gradle plugins { id 'com.android.application' id 'kotlin-android' id 'kotlin-kapt' id 'io.gitlab.arturbosch.detekt' id 'dagger.hilt.android.plugin' } plugins { id("com.android.application") kotlin("android") kotlin("kapt") id("io.gitlab.arturbosch.detekt") id(“dagger.hilt.android.plugin") }
19. Migrate Module Gradle Groovy DSL module gradle Kotlin DSL module gradle plugins { id 'com.android.application‘ id 'kotlin-android‘ id 'kotlin-kapt‘ id 'io.gitlab.arturbosch.detekt‘ id 'dagger.hilt.android.plugin' } plugins { id("com.android.application") kotlin("android") // same as "kotlin-android" kotlin("kapt") // same as "kotlin-kapt" id("io.gitlab.arturbosch.detekt") id(“dagger.hilt.android.plugin") }
20. Migrate Build Types Groovy DSL module gradle Kotlin DSL module gradle buildTypes { getByName("debug") { . . . } create("meetup") { . . . } getByName("release") { . . . } } buildTypes { debug { . . . } meetup { . . . } release { . . . } }
21. Migrate Product Flavors Groovy DSL module gradle Kotlin DSL module gradle productFlavors { create("free") { . . . } create("pro") { . . . } } productFlavors { free { . . . } pro { . . . } }
22. Migrate Module Dependencies Groovy DSL module gradle Kotlin DSL module gradle dependencies { // Dependencies implementation(Dependencies.KTX_CORE) // Annotation processing kapt(AnnotationProcessing.HILT_COMPILER) // Testing testImplementation(TestDependencies.JUNIT4) androidTestImplementation(AndroidTestDependencies.EXT_JUNIT) } dependencies { // Dependencies implementation Dependencies.KTX_CORE // Annotation processing kapt AnnotationProcessing.HILT_COMPILER // Testing testImplementation TestDependencies.JUNIT4 androidTestImplementation AndroidTestDependencies.EXT_JUNIT }
23. Look at migrated gradle in sample project
24. Control Dependencies Versions Github Repository Link: https://github.com/ben-manes/gradle-versions-plugin
25. Comparison: Groovy DSL VS Kotlin DSL Feature Groovy DSL Kotlin DSL Readability ✔ Performance ✔ Better IDE Experience ✔ Compile Time Errors ✔ Less Ambiguity ✔ Scalability ✔
26. Thank you For Your Attention