private static void transformModelValue(Element value, boolean hosted) {
        if ( ! value.hasAttribute("model-id")) return;

        if (hosted) {
            value.setAttribute("url", modelIdToUrl(value.getTagName(), value.getAttribute("model-id"), Set.of()));
            value.removeAttribute("path");
        }
        else if ( ! value.hasAttribute("url") && ! value.hasAttribute("path")) {
            throw onlyModelIdInHostedException(value.getTagName());
        }
    }
Expands a model config value into regular config values.
config-model/src/main/java/com/yahoo/vespa/model/container/xml/ModelIdResolver.java