Refresh token expiration

[alexibz]

I'm trying to detect when a refresh_token would expire, i.e. the 5 cases outlined here. My understanding is that the expired, expiry_at fields of the Oauth client are all related to the access_token rather than the refresh_token. Is there a way to detect refresh_token expiration using the library?

      auth_client = Signet::OAuth2::Client.new(
        authorization_uri: "...."
        token_credential_uri: "....",
        client_id: "...",
        client_secret: "....",
        redirect_uri: "..."
      )
      auth_client.refresh_token = "refresh_token"
      response = auth_client.fetch_access_token!
      response = auth_client.expired?