Make GitProperties plugin only gather properties once

build.gradle

plugins {
    id 'java'
    // Only add the git-properties plugin to the classpath, don't apply (yet)
    id 'com.gorylenko.gradle-git-properties' version '2.2.1' apply false
}

// This plugin is only applied to the root project
apply plugin: GitRootProjectPropertiesPlugin

subprojects {
    apply plugin: "java"
    // This plugin is applied to everything but the root project
    apply plugin: GitSubProjectPropertiesPlugin
}

class GitRootProjectPropertiesPlugin implements Plugin<Project> {
    void apply(Project project) {
        // This is the only place the git properties plugin is applied
        project.apply(plugin: "com.gorylenko.gradle-git-properties")

        // Create a new configuration that has the git-properties attribute associated with it
        project.configurations {
            git {
                canBeConsumed = true
                canBeResolved = false
                visible = false
                Named gitPropertiesType = project.objects.named(GitPropertiesType.class, GitPropertiesType.NAME)
                attributes.attribute(GitPropertiesType.ATTRIBUTE, gitPropertiesType)
            }
        }
        
        // Set this as the default overlaps with other resources
        project.gitProperties.gitPropertiesDir = project.file("${project.buildDir}/git")

        // Map a provider that produces the parent directory of the generated git properties file
        def taskProvider = project.tasks.named(com.gorylenko.GenerateGitPropertiesTask.TASK_NAME)
        def resourceDirProvider = taskProvider.map { task -> task.output.parentFile }
        
        // Add the directory as the artifact associated with the git configuration.  Because this is 
        // a provider mapped from the task, there is an implicit "builtBy" relationship.
        project.artifacts {
            git resourceDirProvider
        }
    }

}

class GitSubProjectPropertiesPlugin implements Plugin<Project> {
    void apply(Project project) {
         // Create a corresponding consumer configuration that has the same "git-properties" attribute.
         project.configurations {
            git {
                canBeConsumed = false
                canBeResolved = true
                visible = false
                Named gitPropertiesType = project.objects.named(GitPropertiesType.class, GitPropertiesType.NAME)
                attributes.attribute(GitPropertiesType.ATTRIBUTE, gitPropertiesType)
            }
        }
        
        // This configuration has a simple project dependency on the root project.  Gradle will find the 
        // git configuration with the matching attribute, whose artifact is the directory of the generated
        // file.
        project.dependencies {
            git project.rootProject
        }

        // Add that directory to the resource dirs of this project
        project.sourceSets.main.resources.srcDirs project.configurations.git
    }
}

// Custom type to use for configuration attributes
interface GitPropertiesType extends Named {
    Attribute<GitPropertiesType> ATTRIBUTE = Attribute.of("com.shelter.gitProperties", GitPropertiesType.class)
    String NAME = "git-properties"
}