def get_urlfullname(cls):
    """Return the url name eventually with router and site namespaces."""
    if cls.router and cls.registry:
        return '{}:{}:{}'.format(cls.router.registry.app_name, cls.router.
            namespace, cls.urlname)
    elif cls.registry:
        return '{}:{}'.format(cls.registry.app_name, cls.urlname)
    elif cls.router:
        return '{}:{}'.format(cls.router.namespace, cls.urlname)
    else:
        return cls.urlname
