We need to Authenticate user from IDP before user is authenticated on Gluu

Required flow of request from user:

• User requested to SP
• SP redirect user to gluu for login with request IDP encoded in base64 in state param
• Gluu extract state param and prepare request and IDP endpoint.
• Send Prepare Request to IDP Endpoint
  • Extract info(whatever required) from state
    • extract endpoint of IDP
  • Prepare request to send user on IDP
  • Redirect User to IDP
• After validating user from IDP its redirected back to SP.

The Image below show the Flow of Passport SAML Authentication