Migrating to build.gradle.kts: in 15 minutes

Kotlin DSL — Better player in town

If you are among those people who has no idea of how to write Gradle in groovy then kotlin DSL is the one for you.

Reason to use kotlin scripts

• Compile time error ❤
• Auto completion
• Source navigation
• Possibility to use extensions
• You have some idea of what you are doing ❤️
• Highly extendable

Why type-safe build logic ?

• Improved Developer experience
• Authoring build logic
• Troubleshooting build related issues
• IDE Support ❤️
• Shorter feedback cycle ❤️
• Less error prone on runtime

Migrate Gradle to kotlin scripts

Migration to kotlin scripts from groovy is very simple and straight forward.

1) replace single quotes with double

2) renaming .gradle to .gradle.kts

3) verify gradle version greater than 5

Step by step Android groovy to kotlin DSL

The 3 files written in groovy will be migrated to kotlin DSL

1) settings.gradle

• Rename file ‘settings.gradle’ to ‘setting.gradle.kts’
• Replace single quotes to double quotes

settings.gradle

TO

settings.gradle.kts

Sync project and make sure it builds successfully. Do not move to next step without fixing the setting.gradle file

2) Project’s build.gradle

• Rename build.gradle to build.gradle.kts
• Replace single quotes to double quotes
• The class path is a function now which has String parameters.

Dependencies

build.gradle

TO

build.gradle.kts

Clean Task

The clean task will be little different in Kotlin script

build.gradle

TO

build.gradle.kts

Repositories

build.gradle

TO

build.gradle.kts

Sync project and make it build successfully.

3) App’s build.gradle

This is the tricky part among the 3 major steps. This file has to be dealt with one step at a time. In Groovy, every plugin was applied individually but in Kotlin, plugins{} block applies all the plugins within a single block.

So, before we could start we get back to our golden steps.

• Rename build.gradle to build.gradle.kts
• Replace single quotes to double quotes
• Follow the below steps, one block at a time

Plugins

build.gradle

TO

build.gradle.kts

In Kotlin scripts id() and kotlin() functions are used to apply plugins.

id() is used for all plugins.

kotlin() is used for kotlin specific functions. You can also omit the ‘kotlin-’ prefix. dash(-) will be replaced by dot(.)

build.gradle.kts

Android

build.gradle

TO

build.gradle.kts

Build Types

This is perhaps the block which is not simple as the others.

build.gradle

TO

build.gradle.kts

The other functions be pretty easy to figure out.

Product Flavors

build.gradle

TO

build.gradle.kts

Dependencies

The functions implementation, testImplementation, androidTestImplementation, debugImplementation etc. are pretty simple to figure out, following the kotlin function pattern.

build.gradle

TO

build.gradle.kts

Sync and feel amazed

Note: There seem to be some changes on Kotlin 1.4. Stay in touch for updated blog