Here's an example of how things could work.
Worst case, we don't get back any 'id' when user authenticates via GitHub. So we only have the 'login' name to work with. Note: all queries below are done with my non-privileged account credentials. (Actually, the queries can be made unauthenticated, but the API rate limits are lower.)
At initial authentication time:
- Query for details of login. The GraphQL query is: