Google calendar v3 returns 403 Insufficient Permission

Question

I've been trying to access Calendar v3 API with a service account. I have already added the scope https://www.googleapis.com/auth/calendar from the admin console and shared my calendar with that service account's email address.

I have also been accessing https://www.googleapis.com/auth/coordinate scope with the very same service account and it works fine.

Also, tried revoking access as said here: Why is Google Calendar API (oauth2) responding with 'Insufficient Permission'?

All that, and I am still getting;

{"error"=>
  {"errors"=>
    [{"domain"=>"global",
      "reason"=>"insufficientPermissions",
      "message"=>"Insufficient Permission"}],
   "code"=>403,
   "message"=>"Insufficient Permission"}}

Am i missing something?

Answer 1

Try to add to you scope 'userinfo.email' and enable in Developers console "Contacts API" and "Google+ API". I've spent 2 weeks searching for answer to this question, and this trick has worked for me.