public function loadRoleAssignmentForUser($userId, $roleId, Request $request)
    {
        $user = $this->userService->loadUser($userId);
        $roleAssignments = $this->roleService->getRoleAssignmentsForUser($user);

        foreach ($roleAssignments as $roleAssignment) {
            if ($roleAssignment->getRole()->id == $roleId) {
                return new Values\RestUserRoleAssignment($roleAssignment, $userId);
            }
        }

        throw new Exceptions\NotFoundException("Role assignment not found: '{$request->getPathInfo()}'.");
    }