I have applied the `kotlin("multiplatform")` plugi...

# gradle

[CLOVIS]

I have applied the kotlin("multiplatform") plugin to a build. When running ./gradlew :components , I get:

No components defined for this project.
Note: currently not all plugins register their components, so some components may not be visible here.

Is this planned? Is there a reason in particular this cannot be done?

I would like to add a new variant to the Kotlin Multiplatform artifacts, by having it be mentioned in the Gradle Module Metadata for the Multiplatform publication. Is there another way to add information to it?

[Jeff Lockhart]

You might find this issue I created relevant. In my case, I needed to add Gradle Module Metadata to an Android component. The Android Gradle plugin uses the Kotlin Gradle plugin under the hood. I was able to access the AdhocComponentWithVariants reference via reflection. It would be nice if my PR got a look to open up the API directly.

[mbonnin]

I was using reflection too. Issue upvoted ⭐

[CLOVIS]

…why does the KGP team always do things differently from the Gradle team? 😐

[CLOVIS]

Thank you both for the workarounds.

[CLOVIS]

I have a task that generates a ZIP file. I also have an outgoing configuration that contains that ZIP file (added as artifact) as well as multiple variant declarations. I'd like to add this configuration to the multiplatform component's Gradle Module Metadata so it can be found using variant-aware dependency resolution under the same artifact name as the project itself.

I tried to use @mbonnin's workaround but I'm confused: it gives me access to a few KotlinTargetComponent s, but these don't seem to implement AdhocComponentWithVariants , so how I can add my own variants to them?

[Jeff Lockhart]

My use case was with an Android module and seems this API has changed in 1.9.20, since I accessed it with reflection, invalidating my PR. (I'm assuming this will affect my code after updating to an AGP version using a version of the KGP with this API change.)

It looks like the AdhocComponentWithVariants reference should be accessible alongside the KotlinTargetComponent reference if you can go up another level to the KotlinTargetSoftwareComponent object.

And it appears you can get the KotlinTargetSoftwareComponent reference from the KotlinTarget.components property, rather than KotlinTarget.kotlinComponents in @mbonnin’s reflection method, which looks to be accessible without reflection, but possibly requiring an opt-in. You might try casting to KotlinTargetSoftwareComponentImpl and accessing adhocComponent via reflection.

[CLOVIS]

I see. I managed to get a KotlinTargetSoftwareComponent instance following what you said, but I'm not sure how to access the AdhocComponentWithVariants from that.

Using component::class.members.find { it.name == "adhocComponent" } , I do get access to the field, however if I try to call it I get:

class kotlin.reflect.jvm.internal.calls.CallerImpl$FieldGetter cannot access a member of class org.jetbrains.kotlin.gradle.plugin.mpp.KotlinTargetSoftwareComponentImpl with modifiers "private final"

Since it's a private field, no getter is generated, so I cannot use Java reflection with setAccessible(true) . Is there another way to access the field?

[Jeff Lockhart]

You should be able to call setAccessible(true) on a field reference. Try:

val adHocField = Class.forName("org.jetbrains.kotlin.gradle.plugin.mpp.KotlinTargetSoftwareComponentImpl")
    .declaredFields.find { it.type == AdhocComponentWithVariants::class.java }
adHocField?.isAccessible = true

[CLOVIS]

Reading https://docs.gradle.org/current/userguide/publishing_customization.html, it seems that adding the variant to the AdhocComponentWithVariants should be enough for everything to be published, right?

My variant looks normal to me:

--------------------------------------------------
Variant exposedKotlinJsResources
--------------------------------------------------

Capabilities
    - example-kmp:core:unspecified (default capability)
Attributes
    - dev.opensavvy.resources    = Regular
    - org.gradle.category        = library
    - org.gradle.libraryelements = resources
Artifacts
    - build/distributions/core-kjs-assets.zip (artifactType = zip, classifier = kjs-assets)

However, it doesn't appear in the .module files when calling ./gradlew publishToMavenLocal 😕

[CLOVIS]

Nevermind, it was an initialization order issue. With a small afterEvaluate , it now works 🙂

[CLOVIS]

Thanks a lot! Now I just have some cleanup to do and I'll be able to announce this