code: function log(requester, level) {
      var context = requester.context;
      var logger = context.data.logger;
      if (!logger || !logger[level]) {
          return;
      }
  
      var args = Array.prototype.slice.call(arguments, 2);
      args[0] = 'AJAX-' + requester.uid + ' ' + args[0];
      logger[level].apply(logger, args);
  }
docs: 纪录日志
  
  @inner
  @param {Object} requester 请求对象
  @param {string} level 日志级别