TransformerAction is not triggered on dependency resolution - gradle

Question

I would like to transform some dependencies when Gradle resolves them.
I have followed the 'Transforming dependency artifacts on resolution' documentation, but my TransformAction is not triggered.
I have
created a custom configuration, gitHub
created custom attributes, and both
applied them to the gitHub configuration,
and registered them in the dependencies {} block)
created and registered a custom TransformAction.
created a task, resolveGitHubDependencies, that will resolve the gitHub configuration.
I have tried a few different adjustments, but nothing seems to have an impact.
What am I missing? Or is this a bug?
Here's the code I've created. It can be tested by running ./gradlew resolveGitHubDependencies. I expect that MyTransformer will print some log statements, but it doesn't print anything.
import org.slf4j.LoggerFactory
plugins {
base
}
repositories {
ivy("https://github.com/") {
name = "GitHub"
patternLayout {
artifact("/[organisation]/[module]/archive/[revision].[ext]")
artifact("/[organisation]/[module]/releases/download/[revision]/[module](-[revision]).[ext]")
}
metadataSources { artifact() }
}
}
// from https://github.com/gradle/gradle/issues/19707
val transformed = Attribute.of("my-library.transformed", Boolean::class.javaObjectType)
val dependencySource = Attribute.of("dependency source", String::class.java)
// my custom configuration - I want to transform all dependencies from this configuration
val gitHub by configurations.creating {
isCanBeConsumed = false
isCanBeResolved = true
attributes {
attribute(dependencySource, "gitHub")
attribute(transformed, false)
}
}
// this is the transformer that I expect to be triggered on dependency resolution
abstract class MyTransformer : TransformAction<MyTransformer.Parameters> {
private val logger = LoggerFactory.getLogger(this::class.java)
interface Parameters : TransformParameters {
#get:Input
val sourceAttributes: MapProperty<Attribute<*>, Any?>
}
#get:PathSensitive(PathSensitivity.NAME_ONLY)
#get:InputArtifact
abstract val inputArtifact: Provider<FileSystemLocation>
override fun transform(outputs: TransformOutputs) {
val sourceAttributes = parameters.sourceAttributes.get()
logger.error("sourceAttributes: $sourceAttributes")
logger.error("sourceAttributes: ${sourceAttributes.keys}")
logger.error("sourceAttributes: ${sourceAttributes.values.joinToString { it.toString() }}")
val input = inputArtifact.get().asFile
outputs.file(input)
}
}
dependencies {
// this is the dependency I want to transform
gitHub("emcrisostomo:fswatch:1.17.1#tar.gz")
attributesSchema {
attribute(dependencySource)
attribute(transformed)
}
// artifactTypes.configureEach {
// attributes.attribute(transformed, false)
// }
registerTransform(MyTransformer::class) {
// from.attributes.attribute(dependencySource, "gitHub")
// to.attributes.attribute(dependencySource, "gitHub")
from.attributes.attribute(dependencySource, "gitHub").attribute(transformed, false)
to.attributes.attribute(dependencySource, "gitHub").attribute(transformed, true)
parameters {
sourceAttributes.set(
from.attributes.keySet().associateWith { key ->
from.attributes.getAttribute(key)
}
)
}
}
}
val resolveGitHubDependencies by tasks.registering(Sync::class) {
group = "gh transform"
from(gitHub)
into(temporaryDir)
}
Gradle version: 7.6