public String toUrl(ConfigKey<?> key, boolean rec) {
            return urlBase + key.getNamespace() + "." + key.getName() + configIdUrlPart(rec, key.getConfigId());
        }
The listing URL for this config in this service

@param key config key
@param rec recursive
@return url
configserver/src/main/java/com/yahoo/vespa/config/server/http/v2/HttpListConfigsHandler.java