@Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        // Track when there's an inflight request.
        if (evt instanceof HttpLifecycleChannelHandler.StartEvent) {
            requestInflight.set(Boolean.TRUE);
        } else if (evt instanceof HttpLifecycleChannelHandler.CompleteEvent) {
            requestInflight.set(Boolean.FALSE);
        }

        super.userEventTriggered(ctx, evt);
    }
User: michaels@netflix.com
Date: 2/8/17
Time: 2:03 PM
zuul-core/src/main/java/com/netflix/netty/common/Http1ConnectionCloseHandler.java