protected def getGraceParam()

in server/src/main/scala/com/twitter/server/handler/ShutdownHandler.scala [21:76]
51 lines of code
6 McCabe index (conditional complexity)

  protected def getGraceParam(request: Request): Option[String] =
    Uri.fromRequest(request).params.get("grace")

  def apply(req: Request): Future[Response] = {
    if (req.method == Method.Post) {
      val specifiedGracePeriod = getGraceParam(req).map { d =>
        try Duration.parse(d)
        catch {
          case e: NumberFormatException =>
            val msg = s"could not parse 'grace' parameter: $d is not a valid duration"
            log.info(
              s"[${req.uri}] from ${req.remoteAddress.getHostAddress} " +
                s"failed to quit due to invalid grace period format",
              e
            )
            return newResponse(
              status = Status.BadRequest,
              contentType = "text/plain;charset=UTF-8",
              content = Buf.Utf8(msg)
            )
        }
      }
      val grace = specifiedGracePeriod.getOrElse(app.defaultCloseGracePeriod)
      log.info(
        s"[${req.uri}] from ${req.remoteAddress.getHostAddress} " +
          s"quitting with grace period $grace"
      )

      // Isolate a current thread (likely netty IO thread)
      // from probable blocking calls inside app.close.
      val ctx = Local.save()
      new Thread(
        () =>
          try {
            Local.restore(ctx)
            app.close(grace)
          } catch {
            case th: Throwable =>
              log.error("Exception when asking an app to close", th)
          },
        "shutdown-handler" // thread name
      ).start()

      newOk("quitting\n")
    } else {
      log.info(
        s"ignoring [${req.uri}] from ${req.remoteAddress.getHostAddress}, because it is a ${req.method}, not a POST"
      )
      newResponse(
        status = Status.MethodNotAllowed,
        headers = Seq(("Allow", "POST")),
        contentType = "text/plain;charset=UTF-8",
        content = Buf.Empty
      )
    }
  }