create a groovy connection

Connection.groovy

class Connection {
    String urlPath

    private String username = project.properties.username
    private String password = project.properties.password
    private String basicAuth = "$username:$password".bytes.encodeBase64().toString()
    URL url = urlPath.toURL();

    InputStream getStream() {
        URLConnection connection = url.openConnection();
        connection.setRequestProperty("Authorization","Basic $basicAuth");
        InputStream inputStream = connection.getInputStream();
        return getStream()
    }
}