protected void verifyRegisteredService(final RequestContext requestContext, final RegisteredService registeredService) {
        val service = WebUtils.getService(requestContext);
        if (registeredService == null || !registeredService.getAccessStrategy().isServiceAccessAllowed(registeredService, service)) {
            LOGGER.debug("Service [{}] is not recognized/allowed by the CAS service registry", registeredService);
            if (registeredService != null) {
                WebUtils.putUnauthorizedRedirectUrlIntoFlowScope(requestContext, registeredService.getAccessStrategy().getUnauthorizedRedirectUrl());
            }
            throw UnauthorizedServiceException.denied("Rejected");
        }
    }
Load saml metadata into request context.

@param requestContext    the request context
@param entityId          the entity id
@param registeredService the registered service
support/cas-server-support-saml-mdui/src/main/java/org/apereo/cas/support/saml/mdui/web/flow/SamlMetadataUIParserAction.java