Unable to consume api in portal if they require oauth client grant

[success:false,result:,error:[title=Something went wrong, message=Failed to connect to some endpoint, detail=Geen details beschikbaar],connectedSystem:[Connected System:],binaryDoc75MbLimitExceeded:false]

{"HouseNumber":"23","HouseNumberAddition":"","PostalCode":"2012Gb"}

This api works fine with same user when called through site but on portal it does not works even after every security is fine. 

When will appian open portals to connect with oauth 2.0 connected system with portals?

I was checking the portal error log and found out something very interesting. They are not allowing the portal user to read this secure credentials of connected system

The appian.sec shared security token file is not present, is unreadable or invalid. This engine will not require a security token for connections.


For now i know the solution is to make this endpoint public and consume in portal. 
But this is very realistic scenario where we have to consume the endpoint in portals which require oauth.
When can appian extend the functionality to support search sensitive api with control access using outh permissions?