BuildService + projectsEvaluated callback example

settings.gradle.kts

import org.gradle.tooling.events.FinishEvent
import javax.inject.Inject

abstract class TraceService : BuildService<TraceService.Parameters>, org.gradle.tooling.events.OperationCompletionListener {

    private
    var projectsEvaluated = false

    interface Parameters : BuildServiceParameters {
    }

    fun onProjectsEvaluated() {
        println("onProjectsEvaluated()")
        projectsEvaluated = true
    }

    override fun onFinish(event: FinishEvent) {
        if (!projectsEvaluated) {
            println("from the cache!")
        }
        println("onFinish($event)")
    }
}

open class TraceServicePlugin @Inject constructor(
    private val buildEventsListenerRegistry: BuildEventsListenerRegistry
) : Plugin<Settings> {

    override fun apply(target: Settings) {
        target.gradle.run {
            val service = sharedServices.registerIfAbsent("traceService", TraceService::class) {
                parameters {
                    // configure service here
                }
            }
            buildEventsListenerRegistry.onTaskCompletion(service)
            projectsEvaluated {
                service.get().onProjectsEvaluated()
            }
        }
    }
}

apply<TraceServicePlugin>()

That's a great thread, thanks for sharing. Lots of people are struggling with this :)

Luckily that approach is working for me so far. I am uncomfortable that I'm checking an interface match, since Gradle could possibly invent some different failure-ish type in the future and my code will silently stop working, which will be a pain to debug.