code: @Override
      public Map<String, Object> toSource() {
          Map<String, Object> sourceMap = new HashMap<>();
          if (urlId != null) {
              addFieldToSource(sourceMap, "urlId", urlId);
          }
          if (docId != null) {
              addFieldToSource(sourceMap, "docId", docId);
          }
          if (order != null) {
              addFieldToSource(sourceMap, "order", order);
          }
          if (queryId != null) {
              addFieldToSource(sourceMap, "queryId", queryId);
          }
          if (queryRequestedAt != null) {
              addFieldToSource(sourceMap, "queryRequestedAt", queryRequestedAt);
          }
          if (requestedAt != null) {
              addFieldToSource(sourceMap, "requestedAt", requestedAt);
          }
          if (url != null) {
              addFieldToSource(sourceMap, "url", url);
          }
          if (userSessionId != null) {
              addFieldToSource(sourceMap, "userSessionId", userSessionId);
          }
          return sourceMap;
      }
docs: ======