init.gradle

import org.gradle.api.UnknownTaskException
import org.gradle.api.tasks.bundling.AbstractArchiveTask

afterProject { project ->
    // Only do this on root project for now. 
    // We are not sure about multi-project builds - we will come back later.
    if (project != rootProject) {
        return
    }

    // Check if the project is still using default archivesBaseName.
    // Emit an error if so.
    if ("modid" == project.archivesBaseName) {
        println "::error::Using default value ('modid') for archive base name; this is doomed to conflicts, and thus not allowed."
        throw new RuntimeException("Using default archiveBaseName is not allowed, please edit your build.gradle!")
    }

    // Try locating the task that produces production-ready artifact.
    // The precedence, from high to low, is as following:
    //   1. If `teaconArtifactTask' is defined in project extension, use the value specified there.
    //   2. If plugin `com.github.johnrengelman.shadow` is present, use `shadowJar` from that plugin.
    //   3. If `remapJar` exists, use that task
    //   4. Use `jar`, failing if not found.
    // The task is expected to have type of org.gradle.api.tasks.bundling.AbstractArchiveTask.
    def targetTask = project.jar
    if (project.pluginManager.hasPlugin("com.github.johnrengelman.shadow")) {
        targetTask = project.tasks.shadowJar
    }
    if (project.tasks.findByName('remapJar')) {
        targetTask = project.tasks.remapJar
    }
    if (project.ext.has("teaconArtifactTask")) { 
        // TODO Deprecate this, nobody uses this so far.
        targetTask = project.ext.teaconArtifactTask
    }
    assert targetTask instanceof AbstractArchiveTask

    // Check if the artifact id contains space. If so, replace it with hyphen.
    // Regex [A-Za-z0-9_\-.]+ shall match all valid artifactId.
    if (!(project.archivesBaseName ==~ /[A-Za-z0-9_\-\.]+/)) {
        println '::warning::Using whitespace in archivesBaseName is not recommended. Replacing it with hyphen. ' + 
                'It is recommended to make your archivesBaseName comply with the following RegEx: [A-Za-z0-9_\\-.]+'
        // This `tr` method works in a similar fashion as of that Unix utility with the same name.
        project.archivesBaseName = project.archivesBaseName.tr(' ', '-')
    }
    
    // Append GitHub Action run number as part of the version number.
    // We use hyphen to comply both Maven-style versioning (build number)
    // as well as SemVer (pre-release version number).
    project.version += System.env.GITHUB_RUN_NUMBER ? "-${System.env.GITHUB_RUN_NUMBER}" : "-private"

    println "Target:" + targetTask.archivePath.absolutePath

    project.tasks.named('build').configure {
        doLast {
            if (System.env.GITHUB_ACTIONS) {
                println "::set-output name=filename::${targetTask.archiveName}"
                println "::set-output name=artifact::${targetTask.archivePath.absolutePath}"
            }
        }
    }
}