code: protected function resourceAttributes($record = null)
      {
          return $this->validatorFactory()->attributes(
              $this->attributeRules($record),
              $this->attributeMessages($record),
              $this->attributeCustomAttributes($record),
              function (Validator $validator) use ($record) {
                  return $this->conditionalAttributes($validator, $record);
              },
              function (ResourceObjectInterface $resource, $record) {
                  return $this->extractAttributes($resource, $record);
              }
          );
      }
docs: Get a validator for the resource attributes member.
  
  @param object|null $record
  @return AttributesValidatorInterface