private function executePostRequest($str_action, $obj_request_body = null)
    {
        $arr_options = [];
        if(null !== $obj_request_body) {
            $arr_options['json'] = $obj_request_body;
        }
        $obj_response = $this->httpClient()->post($this->actionUrl($str_action), $arr_options);
        $this->obj_last_response = json_decode((string)$obj_response->getBody());
    }