Daml OAuth IAM implementation

Hello,
While reading the Daml oAuth middleware concept, I came across below link which explains scala binding authorization. I would like to set up a system that manages these authorizations. I have looked at the documentation but still it is not clear how it can be implemented. Please help me to understand how it can be implemented.
https://docs.daml.com/1.9.0/app-dev/bindings-scala/index.html#scala-bindings-authorization