@Override
    public void operationComplete(ChannelFuture future) {
      logger.trace("scheduling closure of channel {}", future.channel());
      future.channel().eventLoop().schedule(() -> {
        nettyMetrics.delayedCloseActivatedCount.inc();
        if (future.channel().isActive()) {
          logger.trace("closing channel {}", future.channel());
          nettyMetrics.delayedCloseExecutedCount.inc();
          future.channel().close();
        }
      }, nettyConfig.nettyServerCloseDelayTimeoutMs, TimeUnit.MILLISECONDS);
    }
A {@link ChannelFutureListener} that closes the {@link Channel} which is
associated with the specified {@link ChannelFuture} after certain delay which is configured through {@link NettyConfig}.
ambry-rest/src/main/java/com/github/ambry/rest/NettyResponseChannel.java