I am trying to implement a Google App Engine Go application that will use OAuth and OAuth2 for login. I wonder if this is possible, and if so, how to do it? Can someone give an example of this?
You can use goauth2 to implement OAuth2 client in App Engine
You can then register your users with your Google account by requesting areas https://www.googleapis.com/auth/userinfo.profileas shown in Using OAuth 2.0 to Log In
https://www.googleapis.com/auth/userinfo.profile