SCarman's spark job API on top of existing API

sparkjobapi.scala

package spark.jobserver.api

import com.typesafe.config.Config
import org.scalactic._
import spark.jobserver.api._

trait ContextProvider[C] {
  val ctx: C with ContextLike = null
  def context: C with ContextLike = ctx
}

trait SimpleSparkJob[R, CX] {
  type JobOutput = R
  type JobData = Config
  type C = CX
  
  def runJob(runtime: JobEnvironment, data: Config): R
  
  def validate(runtime: JobEnvironment, config: Config): Config

  val baseSparkJob = new SparkJobBase with ContextProvider[CX] {
    def runJob(sc: C, runtime: JobEnvironment, data: JobData): JobOutput = {
      ctx = sc
      runJob(runtime, data)
    }
  
    def validate(sc: C, runtime: JobEnvironment, config: Config): JobData Or Every[ValidationProblem] = {
      try {
        Good(validate(runtime, config))
      } catch {
        case e: Exception => Bad(SingleProblem(e.getMessage))
      }
    }
  }
}