'Revoke a role from user/group on either a domain or project.'

@controller.protected(callback=functools.partial(_check_grant_protection, allow_no_user=True))
def revoke_grant(self, request, role_id, user_id=None, group_id=None, domain_id=None, project_id=None):

    self._require_domain_xor_project(domain_id, project_id)
    self._require_user_xor_group(user_id, group_id)
    self.assignment_api.delete_grant(role_id, user_id, group_id, domain_id, project_id, self._check_if_inherited(request.context_dict), request.context_dict)
