How to move a gradle function from build.gradle into a plugin?

Question

Currently, I have a few utility functions defined in the top level build.gradle in a multi-project setup, for example like this:

def utilityMethod() {
    doSomethingWith(project) // project is magically defined
}

I would like to move this code into a plugin, which will make the utilityMethod available within a project that applies the plugin. How do I do that? Is it a project.extension?

Answer 1

This seems to work using:

import org.gradle.api.Plugin
import org.gradle.api.Project

class FooPlugin implements Plugin<Project> {
    void apply(Project target) {
        target.extensions.create("foo", FooExtension)
        target.task('sometask', type: GreetingTask)
    }
}
class FooExtension{
    def sayHello(String text) {
        println "Hello " + text
    }
}

Then in the client build.gradle file you can do this:

task HelloTask << {
    foo.sayHello("DOM")
}

c:\plugintest>gradle -q HelloTask
Hello DOM

https://docs.gradle.org/current/userguide/custom_plugins.html