SBT Build plugin for Hadoop legacy jar format

build.scala

object build extends Build {
  val maestroJar = TaskKey[File]("maestro-jar", "Creates a packaged jar that works for maestro")

  def allFiles(base: File): Seq[File] = {
    val finder: PathFinder = PathFinder(base).***
    finder.get
  }

  val maestroJarSettings: Seq[Project.Setting[_]] = inTask(maestroJar)(Seq(
    artifactPath <<= artifactPathSetting(artifact),
    cacheDirectory <<= cacheDirectory / maestroJar.key.label
  )) ++ Seq(
    publishArtifact in maestroJar <<= publishMavenStyle,
    mainClass in maestroJar <<= mainClass in run in Compile,
    packageOptions in maestroJar <++= (mainClass in maestroJar).map {
      case Some(mainClass) => Seq(ManifestAttributes((MAIN_CLASS, mainClass)))
      case _ => Seq()
    },
    mappings in maestroJar <<= (products in Compile, dependencyClasspath in Runtime).map {(products, classpath) =>
      println(products)
      val thisArtifactMapping: Seq[(File, String)] = products.map(f => {
        val topLevel = List.fromArray(f.list()).map(t => new File(f, t))
        val children = topLevel.flatMap(x => allFiles(x))
        children.map(c => (c, Path.relativizeFile(f, c)))
          .filter{_ match {
            case (_, None) => false
            case (_,Some(_)) => true
            }
          }
          .map{x => (x._1,x._2.getOrElse(f).toString)}
      }).flatten
      println(thisArtifactMapping)
      val deps: Seq[(File, String)] = {
          val allDeps = Build.data(classpath).map(f => (f, (file("lib") / f.name).getPath))
          allDeps.filterNot(_._1 == artifact)
      }
      thisArtifactMapping ++ deps
    },
    maestroJar <<= (mappings in maestroJar, artifactPath in maestroJar, packageOptions in maestroJar, cacheDirectory in maestroJar, streams) map {
      (mappings, output, packOpts, cacheDir, s) =>
        val packageConf = new Package.Configuration(mappings, output, packOpts)
        Package(packageConf, cacheDir, s.log)
        output
    }
  )

}