AuthSession / Oauth2 : Resource Owner Password Credentials Grant

Hello,
I would like to use the Resource Owner Password Credentials Grant in my app.

I’m aware that’s not the best implementation of Oauth2 and could leads to security problems.
But

  1. The resource owner and the client are “mine”
  2. I can’t change the API aka I must send client_id, client_secret, username, password, grant_type:'password' in order to receive tokens

I was reading and trying ot use AppAuth but it’s “deprecated” and I don’t see how I could possibly send all those params …
Should I use OAuthProps. additionalParameters in order to add my username/password/grant_type to the request ? (It didn’t work)

The AuthSession Doc isn’t very clear either…

I’ve took a look at react-native-app-auth package but still don’t see the “Resource Owner Password Credentials Grant” flow well described …

Must I handle the OAuth workflow on my own ? :confused:

(SDK 40.0.1 for Android and iOS)