code: function initGetOne(router, adminCGIBase, pluginName, handlerNameField, callback) {
      router.get(`${adminCGIBase}/${pluginName}/:${handlerNameField}`, callback);
  }
docs: 获得指定的 handler 信息
  @param router
  @param adminCGIBase
  @param pluginName
  @param handlerNameField
  @param callback