How to publish signatures to Maven Central?

I’m using the signing and maven-publish plugins as follows to publish a JVM library to Maven Central:

signing {
    setRequired {
        gradle.taskGraph.allTasks.any { it is PublishToMavenRepository }
    }
    val signingKey: String? by project
    val signingPassword: String? by project
    useInMemoryPgpKeys(signingKey, signingPassword)
    sign(configurations.archives.get())
}
publishing {
    publications {
        create<MavenPublication>("default") {
            from(components["java"])

            pom {
                name.set(rootProject.name)
                description.set("Relaynet JVM library")
                url.set("https://github.com/relaycorp/awala-jvm")
                developers {
                    developer {
                        id.set("relaycorp")
                        name.set("Relaycorp, Inc.")
                        email.set("no-reply@relaycorp.tech")
                    }
                }
                licenses {
                    license {
                        name.set("Apache-2.0")
                    }
                }
                scm {
                    connection.set("scm:git:https://github.com/relaycorp/awala-jvm.git")
                    developerConnection.set("scm:git:https://github.com/relaycorp/awala-jvm.git")
                    url.set("https://github.com/relaycorp/awala-jvm")
                }
            }
        }
    }
    repositories {
        maven {
            url = uri("https://s01.oss.sonatype.org/service/local/staging/deploy/maven2/")
            credentials {
                username = System.getenv("MAVEN_USERNAME")
                password = System.getenv("MAVEN_PASSWORD")
            }
        }
    }
}

The publication is done by running ./gradlew publish from a GutHub action.

However, when I try to close the staging repository, it fails with Failed: Signature Validation:

Those failure messages look correct, considering that those *.asc files aren’t available:

According to the signing plugin, they should be automatically added to the publication,. However, having run ./gradlew publish --dry-run, I don’t think the signing plugin is actually used at all:

+ ./gradlew publish --dry-run
:compileKotlin SKIPPED
:compileJava SKIPPED
:processResources SKIPPED
:classes SKIPPED
:inspectClassesForKotlinIC SKIPPED
:jar SKIPPED
:javadoc SKIPPED
:javadocJar SKIPPED
:sourcesJar SKIPPED
:generateMetadataFileForDefaultPublication SKIPPED
:generatePomFileForDefaultPublication SKIPPED
:publishDefaultPublicationToMavenRepository SKIPPED
:publish SKIPPED

So, how can I get ./gradlew publish to run the signing plugin? Unfortunately, I’m using a third-party tool that runs ./gradlew publish and it won’t allow me to change the arguments passed to Gradle, so any change would have to be done in build.gradle.kts.

Thanks!

Read the section you linked to yourself again and try to understand it.
Then replace sign(configurations.archives.get()) by sign(publishing.publications) and it should work I think. :slight_smile:

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