Authentication with the REST API using custom OAuth

Description

I am integrating RocketChat in my website for my users to chat with each other. And I like to register my users to RocketChat using the same credentials (they use to login to my website) via RESTApi. For that I am exploring OAuth option provided by RocketChat. As I can see RocketChat provided ways to authentication with the REST API for third party app like Facebook, Google etc:

https://docs.rocket.chat/api/rest-api/methods/authentication

But there is no custom app given here in this list.

However they have given how to configure custom application for OAuth here:

But not sure if and how can this be used via REST API

I am looking for how to use custom OAuth to authenticate with RocketChat via REST Api. Any sample or explanation how to use would be really great.

Thanks and anticipation.

Server Setup Information

  • Version of Rocket.Chat Server: 3.7.1
  • Operating System: Linux
  • Deployment Method:
  • Number of Running Instances: 1
  • DB Replicaset Oplog:
  • NodeJS Version: v12.14.0
  • MongoDB Version: 4.0.21
  • Proxy:
  • Firewalls involved:

Any additional Information

Nil