private void Process(string strCommand)
        {
            try
            {
                BookCommand command = JsonConvert.DeserializeObject <BookCommand>(strCommand);

                switch (command.CommandType)
                {
                case BookCommand.SubscribeType.SUBSCRIBE:
                    marketFaced.SubscribeMinibook((IUserChannelNotification)this, command.Stock);
                    break;

                case BookCommand.SubscribeType.UN_SUBSCRIBE:
                    marketFaced.UnSubscribeMinibook((IUserChannelNotification)this, command.Stock);
                    break;
                }
            }
            catch (Exception e)
            {
                logger.LogError("Process", e);
            }
        }