def secured_download(func):
    """Wraps a view to server files securely ONLY when a
    ``FileField`` is returned
    Uses Django when ``DEBUG`` is on else NGINX
    """
    def wrapper(request, *args, **kwargs):
        response = func(request, *args, **kwargs)
        if isinstance(response, FieldFile):
            # response is a ``FieldFile`` we should serve it
            if settings.DEBUG:
                # only serve through Django when DEBUG is on
                stream = serve(request, response.name, settings.MEDIA_ROOT)
                stream['Content-Disposition'] = 'attachment; filename=%s' % \
                                 response.name
                return stream
            else:
                # Use X-Accel-Redirect to serve the file
                stream = HttpResponse('')
                stream['X-Accel-Redirect'] = response.url
                return stream
        return response
    return wrapper