title: How to identify allowed user google calendar api authorization request gmail account
body: <p>I need to find the user response for  authorised request in identification to his gmail account, Actually am trying to send mail regarding the authentication from developers account to users. When user clicks Allow then calendar events are created in their calendar.</p>
  
  <p>But when they deny, Exception pops out stating Not authorised user. I need to find the user mail id and what user doing accepting or denying ? Yeah I tried 
  <a href="https://www.googleapis.com/oauth2/v1/userinfo?alt=json&amp;access_token=youraccess_token" rel="nofollow">this link</a></p>
  
  <p>Example :</p>
  
  <p><a href="https://www.googleapis.com/oauth2/v1/userinfo?alt=json&amp;access_token=ya29.Ci82A9-AcdxxjkatYj5NxwaxmJJybeOq7JwqhBUOCYpFM9xpBKHrWlEVULea4OfM_Q" rel="nofollow">https://www.googleapis.com/oauth2/v1/userinfo?alt=json&amp;access_token=ya29.Ci82A9-AcdxxjkatYj5NxwaxmJJybeOq7JwqhBUOCYpFM9xpBKHrWlEVULea4OfM_Q</a></p>
  
  <p>but i am getting error:</p>
  
  <pre><code>   {
       "error": {
       "errors": [
          {
            "domain": "global",
            "reason":  "insufficientPermissions",
            "message": "Insufficient Permission"
          }
          ],
        "code": 403,
        "message": "Insufficient Permission"
      }
    }
  </code></pre>
  
  <p>Need Assistance Guys.</p>