title: Get logged in user's calendarId
body: <p>I want to retrieve calendar events of the logged in user. The API doc <a href="https://developers.google.com/google-apps/calendar/v3/reference/calendars/get" rel="nofollow noreferrer">here</a> suggests that I need to pass 'primary' as calendarId for the logged in user. </p>
  
  <p>Therefore the URL becomes <code>https://www.googleapis.com/calendar/v3/calendars/primary/</code></p>
  
  <p>I am getting a 401 on this URL.</p>
  
  <pre><code>GET https://www.googleapis.com/calendar/v3/calendars/primary/ 401 ()
  </code></pre>
  
  <p>Can someone please suggest what am I doing wrong.</p>