# What this PR does
Follow up PR to https://github.com/grafana/oncall/pull/4792
Basically if when communicating with Google Calendar's API we encounter
an HTTP 403, or the Google client throws a
`google.auth.exceptions.RefreshError` this means one of three things:
1. the refresh token we have persisted for the user is missing the
`https://www.googleapis.com/auth/calendar.events.readonly` scope (HTTP
403)
2. the Google user has been deleted
(`google.auth.exceptions.RefreshError`)
3. the refresh token has expired (`google.auth.exceptions.RefreshError`)
To prevent scenario 1 above from happening in the future we now will
check that the token has been granted the required scopes. If the user
doesn't grant us all the necessary scopes, we will show them an error
message in the UI:
https://www.loom.com/share/0055ef03192b4154b894c2221cecbd5f
For tokens that were granted prior to this PR and which are missing the
required scope, we will show the user a dismissible warning banner in
the UI letting them know that they will need to reconnect their account
and grant us the missing permissions (see [this second demo
video](https://www.loom.com/share/bf2ee8b840864a64893165370a892bcd)
showing this).
## Checklist
- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
show up in the autogenerated release notes.
---------
Co-authored-by: Dominik <dominik.broj@grafana.com>