private function createJson() {
    $content = $this->getContent()->get();
    $json = json_encode(
      $content,
      JSON_PRESERVE_ZERO_FRACTION |
      JSON_BIGINT_AS_STRING |
      JSON_NUMERIC_CHECK |
      JSON_PRETTY_PRINT |
      JSON_UNESCAPED_SLASHES
    );

    if (!$this->isValidJson($json)) {
      throw new \Nuki\Exceptions\Base('Encoded json string is not valid, check input');
    }
    
    return $json;
  }