docs: public void createIndex(String indexDefinition) {
          assertNotEmpty(indexDefinition, "indexDefinition");
          InputStream putresp = null;
          URI uri = new DatabaseURIHelper(db.getDBUri()).path("_index").build();
          try {
              putresp = client.couchDbClient.executeToInputStream(createPost(uri, indexDefinition,
                      "application/json"));
              String result = getAsString(putresp, "result");
              if (result.equalsIgnoreCase("created")) {
                  log.info(String.format("Created Index: '%s'", indexDefinition));
              } else {
                  log.warning(String.format("Index already exists : '%s'", indexDefinition));
              }
          } finally {
              close(putresp);
          }
      }