gradle-template-example

Advanced gradle template using Kotlin DSL

Introduction

This is an advanced gradle kotlin project template using gradle's kotlin DSL

Features:

• Multimodule setup: Modules reside in modules folder. Please refer to settings.gradle.kts for further information
• buildSrc plugin scripts to be imported like the old groovy apply from format
• Extra properties as an example, as global versions.gradle.kts on buildSrc, overridden on the rootProject and then overridden per module on buildscript {} block
• Preconfigured java and java-test plugin scripts
• Preconfigured kotlin-jvm and kotlin-test plugin scripts, with spotless and klint (java plugin scripts doesn't have any linter)
• Preconfigured junit 5 script plugin with test summary output
• Preconfigured basic idea plugin
• Preconfigured springboot plugin and libraries with exclusions with a spring module with tracing, logging and so.
• .gitignore template
• .gitattributes template
• sample init.gradle.kts properties
• Some logging information added to several tasks, like version and properties output on compileJava, compileKotlin
• More logging information added to test, like logging version of the libraries included
• Different flavour per module (i.e. java module uses assertj and mockito while kotlin uses assertj and mockk
• Modules dependencies: kotlin module depends on java module by implementation flavour
• Gradle Wrapper included in the sources
• Gradle wrapper task example on root build.gradle.kts

This template is offered as it is as a learning resource or as a starting point to override and customize to everyone's needs. Some design choices made are an intentional exaggeration to illustrate with examples what can be done. Please review before using this on production and tailor it to your needs.

Please bear in mind that gradle recommends applying plugins on root project buildscript but that recommendation has been ignored on this template. The reasoning behind this is to make every buildscript minimal. If your buildscripts require the same plugin, please add it to the root buildscript as per gradle recommendations. See https://docs.gradle.org/current/userguide/kotlin_dsl.html#sec:multi_project_builds_applying_plugins for additional information: For example, to load common.gradle.scripts.java plugin on root buildscript but don't apply it:

plugins {
    id("common.gradle.scripts.java") false
}

Then it will be available (loaded) for modules. This might improve your build times if your plugins are shared across modules.

How is it done?

Convention over Configuration.

The template offers a hook, versions.gradle.kts, sitting on buildSrc (that includes the default versions). It also loads versions.gradle.kts sitting on root project to override the versions in buildSrc. The whole idea is to allow a company package buildSrc in either a git subtree, or a custom gradle distribution (see https://docs.gradle.org/current/userguide/organizing_gradle_projects.html#sec:custom_gradle_distribution) to embed a custom buildSrc for the company builds.

Also, modules can override their properties either by adding a buildscript block to override some default versions. Additionally, if the file versions.gradle.kts exists in the module root folder, it will overwrite the parent and buildSrc versions. In the examples provided, the java submodule is overriding jvm target with a buildscript block and the kotlin module is overriding the version of kotlin logging library with a versions.gradle.kts file.

Dummy Tests

Dummy tests exist to force the test task failure.

Single Module projects

• Remove java, kotlin and spring modules
• Add default src at projectRoot folder with the standard convention: $projectRoot/src/{main, test}/{java, kotlin}
• Edit settings.gradle.kts and remove the include section