MDCPropagatingDispatcher

gistfile1.scala

/**
 * A MDC propagating dispatcher.
 *
 * This dispatcher propagates the MDC current request context if it's set when it's executed.
 */
class MDCPropagatingDispatcher(_configurator: MessageDispatcherConfigurator,
                               id: String,
                               throughput: Int,
                               throughputDeadlineTime: Duration,
                               executorServiceFactoryProvider: ExecutorServiceFactoryProvider,
                               shutdownTimeout: FiniteDuration)
  extends Dispatcher(_configurator, id, throughput, throughputDeadlineTime, executorServiceFactoryProvider, shutdownTimeout ) with SLF4JLogging {

  override def execute(runnable: Runnable): Unit = {

    // capture the callee MDC
    val mdcContext = MDC.getCopyOfContextMap
    val id = mdcContext.get("id")
    log.info(s"new id = $id")

    super.execute(new Runnable {

      def run() = {
        // backup the callee MDC context
        val oldMDCContext = MDC.getCopyOfContextMap
        val oldId = oldMDCContext.get("id")
        log.info(s"new oldId = $oldId")
        // Run the runnable with the captured context
        setContextMap(mdcContext)
        try {
          runnable.run()
        } finally {
          // restore the callee MDC context
          setContextMap(oldMDCContext)
        }
      }
    })
  }