IDP 3.3 MFA flow -- checking to see if an authn context class ref was requested

[Jim Fox]

>
> First, I see I can use the isAcceptable method (as included in the distributed example) to see if a requested method has been satisfied. But I'm curious, in this case, about requested methods that haven't been satisfied - namely Duo. How can I get a list of requested authentication context classes? I've looked at the MFA context and authentication context in the JavaDocs, but I don't see anything to help me in those.
>
>
I do something like this (to see if token was requested):

      authCtx = input.getSubcontext("net.shibboleth.idp.authn.context.AuthenticationContext");
      rpCtx = authCtx.getSubcontext("net.shibboleth.idp.authn.context.RequestedPrincipalContext");
      if (rpCtx != null) {
          rps = rpCtx.getRequestedPrincipals();
          tkp = new AuthnContextClassRefPrincipal("urn:oasis:names:tc:SAML:2.0:ac:classes:TimeSyncToken");
          if (rpCtx.getRequestedPrincipals().contains(tkp)) {
            logger.debug("RP requested token login");
          }
      }


Jim