AEM 6.1 - JAVA External Custom Login Module

[#1]

We have a custom (java) login module that was implemented in 5.6 version but its not working after upgrading to 6.0/6.1. 

We understand that in AEM 6 we have to re-create the custom login module using Oak External Login Module or implement org.apache.sling.jcr.jackrabbit.server.security.LoginModulePlugin . We found some articles on the developer forum, but they are not detailed. Need your help on how to achieve this in AEM 6. 

[#2]

I have watched the recent session conducted on external login with LDAP module and that was for LDAP configuration. I am looking substitute for com.day.crx.core.CRXLoginModule if any POC or example code exist. I was looking at this https://github.com/apache/jackrabbit-oak.