code: function jsonRet(req,res) {
      var state = 200;
      var data = {
          code:state,
          message:""
      };
  
      //错误判断（404）
      if(!req.input) {
          state = 404;
          req.app.yolog.log('error','error 404');
      } else if(req.input.error) {
          state = 500;
          data.message = req.input.message ? req.input.message:'';
          req.app.yolog.log('error','error 500',req.input);
      } else {
          data.data = res.proxyData;
      } 
      req.app.yolog.log('verbose','pjax vo: %j',data,{});
      data.code = state;
      res.status(state).json(data);
  }
docs: 返回json的处理
  @param  {Object} input 参数输入
  @param  {Object} res   响应
  @return {void}