Function add_attribute

nanofi/src/api/nanofi.cpp:371–377

* Adds an attribute * @param ff flow file record * @param key key * @param value value to add * @param size size of value * @return 0 or -1 based on whether the attributed existed previously (-1) or not (0) */

 * @return 0 or -1 based on whether the attributed existed previously (-1) or not (0)
 */
int8_t add_attribute(flow_file_record *ff, const char *key, void *value, size_t size) {
  NULL_CHECK(-1, ff, key, value);
  NULL_CHECK(-1, ff->attributes);
  auto attribute_map = static_cast<AttributeMap*>(ff->attributes);
  const auto& ret = attribute_map->insert(std::pair<std::string, std::string>(key, std::string(static_cast<char*>(value), size)));
  return ret.second ? 0 : -1;
}

/**
 * Updates (or adds) an attribute