docs: public boolean createIndex(String name, String type, EsRequest mappings) throws IOException {
          if (indexExists(name)) {
              return true;
          }
  
          CloseableHttpClient client = HttpClients.createDefault();
          HttpPost method = new HttpPost(String.format("http://%s:%d/%s", host, port, name));
          try {
              StringEntity requestEntity = new StringEntity(mappings.toString(), ContentType.APPLICATION_JSON);
              method.setEntity(requestEntity);
              CloseableHttpResponse resp = client.execute(method);
              return resp.getStatusLine().getStatusCode() == HttpStatus.SC_OK;
          } finally {
              method.releaseConnection();
          }
      }