protected String resolveURL(ApiWrapper wrapper, String url) throws IOException {
String result = "";
HttpResponse reso = wrapper.head(Request.to(Endpoints.RESOLVE).with("url", url));
if (reso.getStatusLine().getStatusCode() != HttpStatus.SC_MOVED_TEMPORARILY)
throw new CloudAPI.ResolverException("Invalid status code", reso);
// Header location = reso.getFirstHeader("Location");
if (!reso.containsHeader("Location"))
throw new CloudAPI.ResolverException("No location header", reso);
result = reso.getFirstHeader("Location").getValue();
return result;
}
