AuthenticationInfoPostProcessor - PathInfo is null




We(in AEM 6.4 version) are trying to implement custom post processor by AuthenticationInfoPostProcessor to read SAML response. We are following approach mentioned in this blog Apoorva Ganapathy's Blog: AEM - Processing SAML Response but both httpRequest.getPathInfo() and httpRequest.getParameter("saml_login") are null so we are unable to get hold of SAML response.

Is there any way we can read SAML response in post processor instead of decrypting samlResponse property from user node after successful login?