Support publications with grade metadata feature enabled

[vvlevchenko]

Gradle introduced gradle metadata feature in version 4.6 for which mostly used in native publications. It generate .module file for artifact which contains information about possible variants of artifact and configuration attributes for resolving. This file skipped by current version of plugin.

PR #230 realise metadata file publishing.

[h0tk3y]

+1 for this feature, as Kotlin Multiplatform projects now support publishing Gradle module metadata for simplifying dependency management. Is this going to be supported in the Bintray plugin?

[ilmat192]

Hi @eyalbe4! This issue prevents publishing Kotlin multiplatform libraries to Bintray but the PR mentioned above can fix it. Do you have any plans to merge it?

[fluidsonic]

Workaround which works for us until the Bintray plugin catches up.

build.gradle.kts

tasks.withType<BintrayUploadTask> {
    doFirst {
        publishing.publications
            .filterIsInstance<MavenPublication>()
            .forEach { publication ->
                val moduleFile = buildDir.resolve("publications/${publication.name}/module.json")
                if (moduleFile.exists()) {
                    publication.artifact(object : FileBasedMavenArtifact(moduleFile) {
                        override fun getDefaultExtension() = "module"
                    })
                }
            }
    }
}

Note that we use Gradle Kotlin Script, so for Grovvy-based build.gradle files the code needs to be adjusted.

[dhakehurst]

This is a great workaround, though how do you 'get' the 'publishing' variable

In my multi project, multiplatform build, in the root project 'publishing' is an unresolved reference!

[dhakehurst]

found the answer,
val publishing = extensions.getByType(PublishingExtension::class.java)

[ljacomet]

Finding this issue after having added a similar support to the build-info plugin for Artifactory integration.
@eyalbe4 If I open a PR to enable this plugin, in a similar manner to what was done in jfrog/build-info#265 (and follow up PRs), what would be the objective in terms of supported Gradle versions?
The current version of this build uses Gradle 4.3. It would be awesome to be able to bump this to at least 4.10.3 and leverage some of the APIs introduced on internal types in the 4.x line, not available in 4.3.

[eyalbe4]

Sure @ljacomet,
We'd be happy to merge a PR that supports this.
Thanks!

[martinbonnin]

For the record, you can upload Gradle metadata with the maven-publish plugin bundled with Gradle. That will publish all the .module files:

      maven {
        name = "bintray"
        url = uri("https://api.bintray.com/maven/$subject/$repo/$package/;publish=1;override=1")
        credentials {
          username = username
          password = password
        }
      }

[tsjensen]

Thanks @fluidsonic for this quite sophisticated workaround! 👍

I adapted it for the Groovy DSL (probably imperfectly, but it works for me 😉):

import com.jfrog.bintray.gradle.tasks.BintrayUploadTask
import org.gradle.api.publish.maven.internal.artifact.FileBasedMavenArtifact

tasks.withType(BintrayUploadTask) {
    doFirst {
        publishing.publications.withType(MavenPublication).forEach({ publication ->
            File moduleFile = new File(project.buildDir, "publications/${publication.name}/module.json")
            if (moduleFile.exists()) {
                publication.artifact(new FileBasedMavenArtifact(moduleFile) {
                    protected String getDefaultExtension() {
                        return 'module';
                    }
                })
            }
        })
    }
}

[Danilo-Araujo-Silva]

The workaround provided is not working for me.

Locally, using Maven Local, it is being resolved automatically.
But when uploading to bintray, also with the workaround, the dependency is not resolve automatically.

For example, locally this works:

implementation("com.company:project:1.0.0")

But when using bintray, even when we have the .module uploaded there it is not resolving for me and only the version below is working:

implementation("com.company:project-jvm:1.0.0")

But it seems to be not perfect because when using KScript the second version does not work as well.

[LouisCAD]

@Danilo-Araujo-Silva Replacing this plugin by Gradle's first-party maven-publish plugin, as Martin said in this comment above will solve all your issues.

[tsjensen]

@LouisCAD Really? How will you handle the secondary features, such as synching to Maven Central without going through their complicated workflow?

[LouisCAD]

@tsjensen You are mistaking the maven-publish gradle plugin with Maven Central.
The example I linked uploads to bintray. Please, take the time to read it 🙂

[martinbonnin]

@tsjensen if you're talking about https://github.com/bintray/gradle-bintray-plugin#Maven_Central_Sync, I think (but have never tried so that'll need confirmation) that you can setup Maven Central sync from the UI at bintray.com. Once setup in the UI, bintray should sync every time you push, whether you push with the maven-publish or bintray plugin.

[tsjensen]

@martinbonnin Yes, that's what I mean. I tried hard to get this to run via their UI. It worked, but only when pushing the buttons manually. For automation, this plugin seemed like the only way.

@LouisCAD No, I did not "mix up maven-publish and Maven Central". I am genuinely interested in finding out how to do the Maven Central Sync when publishing to bintray using maven-publish. If you can point us to somewhere this is resolved, then I'll switch!

[martinbonnin]

@tsjensen the maven-publish plugin will not help with bintray specific features like this but you could certainly use the bintray API to automate this separately. It looks like a HTTP POST is everything that is required to sync a given version of a package: https://bintray.com/docs/api/#_sync_version_artifacts_to_maven_central

[LouisCAD]

Ah, I get it now. What Martin just wrote should work for syncing bintray to maven central.

In fact, that's how the gradle-bintray-plugin has been doing it:

gradle-bintray-plugin/src/main/groovy/com/jfrog/bintray/gradle/tasks/BintrayPublishTask.groovy

Line 107 in 67718c3

private void mavenCentralSync(String repoName, String pkgName, String versionName, BintrayUploadTask task) {