Calendar: Additional Scope enforced to be requested when it is not needed

まず、GoogleSignInOptions requestScopes(CalendarScopes.CALENDAR_EVENTS_READONLY) のフローを UserRecoverableAuthIOException と recovery Intent まで追跡します。その動作を外部リファレンスに記載されている Calendar events.list の scope と比較します。readonly scope でイベントを一覧表示したときに、より広い calendar scope が要求されなければ完了です。

Environment details

1. Specify the API at the beginning of the title. Calendar API
2. OS type and version: Android target SDK 33
3. Java version: Android 13
4. version(s): com.google.apis:google-api-services-calendar:v3-rev20230707-2.0.0

Steps to reproduce

1. Sign-In to Google and request Scope CALENDAR_EVENTS_READONLY =
   https://www.googleapis.com/auth/calendar.events.readonly"
2. Retrieve the Calendar Events List for a certain CalendarID
3. Get warning [GoogleAuthUtil] isUserRecoverableError status: NEED_REMOTE_CONSENT, which triggers exception UserRecoverableAuthIOException
4. Upon handling exception, Request_Permission is requesting Scope "https://www.googleapis.com/auth/calendar". This is not needed, as observed in https://developers.google.com/calendar/api/v3/reference/events/list, and selecting only the events.readonly scope

Code example (simplified)

        GoogleSignInOptions mGoogleSignInOptions = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .requestScopes(new Scope(CalendarScopes.CALENDAR_EVENTS_READONLY)) //https://developers.google.com/identity/protocols/oauth2/scopes#calendar
                .build();

        // Build a GoogleSignInClient with the options specified by gso.
        GoogleSignInClient mGoogleSignInClient = GoogleSignIn.getClient(MainActivity.this, mGoogleSignInOptions);
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent, SIGN_IN_REQUEST_CODE); 


            do {
                page++;
                Events events;
                Log.i(appLogTAG, "Sending events request, page "+page);

                events = calendarService.events().list(calendarID).execute();


                List<Event> items = events.getItems();

                for (Event event : items) {
                    //some work
                }

                pageToken = events.getNextPageToken();
                syncToken = events.getNextSyncToken();
            } while (pageToken != null);


        }catch (UserRecoverableAuthIOException e) {
            toastInUI("Error while retrieving data. ");

            //request missing permissions
            Intent intent = e.getIntent();
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            appContext.startActivity(intent);

        } catch (GoogleJsonResponseException e) {
            if (e.getStatusCode() == 410) {
                // A 410 status code, "Gone", indicates that the sync token is invalid.
                Log.e(appLogTAG,"Invalid sync token, clearing event store and re-syncing.");
            } else {
                throw new RuntimeException(e);
            }
        }catch (SocketTimeoutException e) {
            Log.e(appLogTAG, "Timeout while retrieving data.");
            toastInUI("Timeout while retrieving data.");
        }catch (IOException e) {
            Log.e(appLogTAG, "Unknown error.");
            throw new RuntimeException(e);
        }
       

Stack trace

W  [GoogleAuthUtil] isUserRecoverableError status: NEED_REMOTE_CONSENT

External references such as API reference guides

• https://developers.google.com/calendar/api/v3/reference/events/list

Any additional information below

I have tried debugging to understand where the enforced permission request comes from without success. From the link in External References the requested Scope is enough to list all events in the Calendar.

Thanks!