403 Error "not Authorized To Access This Resource/api" Google Admin Sdk In Web App Even Being Admin

I'm struggling to find the problem since two days without any idea why I get this error now even though the app was fully functional one month before. Among the tasks done by the w

Solution 1:

Finally, after knocking my head against the wall, I found what was the problem: the groupKey used to get the members of a group https://www.googleapis.com/admin/directory/v1/groups/groupKey/members had a trailing whitespace.

Yes, that's all. I just had to strip the string in the code (one line in Python) and it all went well.

All I did, searching for permissions / client ID / Delegation of Authority was for nuts it seems.

Seriously, the 403 error “Not Authorized to access this resource/api” of Google's API could have been more explicit.