I try to use fetch list of Calendar Resources (https://support.google.com/a/answer/60766?hl=en) from my company's Google Apps, using Google API. I try to use it using OAuth 2.0 Playground page (https://developers.google.com/oauthplayground). What I do:
1. I select scope & authorize API with my company's admin account and using this scope https://apps-apis.google.com/a/feeds/calendar/resource/
2. I xchange authorization code for tokens
3. I put a requested URL: https://apps-apis.google.com/a/feeds/calendar/resource/2.0/my-company-domain-url/
4. I send request and I get error:
HTTP/1.1 403 Forbidden
Alternate-protocol: 443:quic,p=1
Content-length: 207
X-xss-protection: 1; mode=block
X-content-type-options: nosniff
Transfer-encoding: chunked
Expires: Fri, 18 Dec 2015 22:09:43 GMT
Server: GSE
-content-encoding: gzip
Cache-control: private, max-age=0
Date: Fri, 18 Dec 2015 22:09:43 GMT
X-frame-options: SAMEORIGIN
Alt-svc: quic=":443"; ma=604800; v="30,29,28,27,26,25"
Content-type: text/html; charset=UTF-8
<HTML>
<HEAD>
<TITLE>You are not authorized to access this API.</TITLE>
</HEAD>
<BODY BGCOLOR="#FFFFFF" TEXT="#000000">
<H1>You are not authorized to access this API.</H1>
<H2>Error 403</H2>
</BODY>
</HTML>
I've already enabled this API in Developers Console.
Question: what else do I need to do to make it work, i.e. be able to fetch calendar resources list?