inititally i thought there could be a way and i tried the following
func DoHTTPProbe(url *url.URL, headers http.Header, client HTTPGetInterface) (probe.Result, string, error) {
    // ...
    body := string(b)
    if res.StatusCode >= http.StatusOK && res.StatusCode < http.StatusBadRequest {
        glog.V(4).Infof("Probe succeeded for %s, Response: %v", url.String(), *res)
        return probe.Success, body, nil
    }
    glog.V(4).Infof("Probe failed for %s with request headers %v, response body: %v", url.String(), headers, body)
    return probe.Failure, fmt.Sprintf("HTTP probe failed with statuscode: %d", res.StatusCode), nil
}
But it doesnt work