(Session)
| 17 | BeginAuth(state string) (Session, error) |
| 18 | UnmarshalSession(string) (Session, error) |
| 19 | FetchUser(Session) (User, error) |
| 20 | Debug(bool) |
| 21 | RefreshToken(refreshToken string) (*oauth2.Token, error) // Get new access token based on the refresh token |
| 22 | RefreshTokenAvailable() bool // Refresh token is provided by auth provider or not |
no outgoing calls