cid2.scala

object CorrelationId {
  val CorrelationIdHeader = "X-Correlation-ID"
  
  def setCorrelationIdMiddleware(service: HttpRoutes[Task]): HttpRoutes[Task] = 
    Kleisli { req: Request[Task] =>
      val cid = req.headers.get(CaseInsensitiveString(CorrelationIdHeader)) match {
        case None => newCorrelationId()
        case Some(cidHeader) => cidHeader.value
      }

      localCid.update(Some(cid))
      logger.info("Starting request")
      service(req)
    }
}