protected function _callApiPreparations(
    $httpmethod, $method, $method_template, $params, $multipart, $app_only_auth
  )
  {
    $url             = $this->_getEndpoint($method, $method_template);
    $request_headers = [];
    if ($httpmethod === 'GET') {
      // GET
      list ($authorization, $url) =
        $this->_callApiPreparationsGet($httpmethod, $url, $params, $app_only_auth);
    } else {
      // POST
      list ($authorization, $params, $request_headers) =
        $this->_callApiPreparationsPost($httpmethod, $url, $method, $method_template, $params, $multipart, $app_only_auth);
    }
    if ($app_only_auth) {
      $authorization = $this->_getBearerAuthorization();
    }

    return [
      $authorization, $url, $params, $request_headers
    ];
  }