I’m generating an XML feed to be used from outside of a Rails
application. The feed should include URLs for associated images. I’m
using image_path to generate the image URLs. This respects
relative_url_root, but all it gives me is the absolute path of the
image relative to the domain root (e.g. /image_assets/1234/
my_image.jpg). Is there a standard way to get fully specified absolute
URLs to images? I looked at url_for, which implements an :only_path
option, but that option is only available for controller paths.