protected void configureHttpRequest(final Http request) {
        val factory = httpClient.httpClientFactory();
        if (factory.getProxy() != null) {
            request.setProxy(factory.getProxy().getHostName(), factory.getProxy().getPort());
        }
    }
This is {@link BaseDuoSecurityAuthenticationService}.

@author Misagh Moayyed
@since 5.1.0
support/cas-server-support-duo-core/src/main/java/org/apereo/cas/adaptors/duo/authn/BaseDuoSecurityAuthenticationService.java