code: public String getConfigAttributeWithDefaultValue(Map<String, Object> props, String key, String defaultValue) {
          String result = getAndTrimConfigAttribute(props, key);
          if (key != null && result == null) {
              if (defaultValue != null) {
                  result = defaultValue;
              }
          }
          return result;
      }
docs: Returns the value for the configuration attribute matching the key provided. If the value does not exist or is empty, the
  provided default value will be returned.