title: Any samples showing the use of OAuth2 service (server to server) accounts
body: <p>All the samples I'v seen only support 'user' accounts where a user has to be present.</p>
  
  <p>Looks like latest version of OAuth2 supports service accounts for server to server authentication where humans not present but I am struggling to find any libraries that support it or examples of in use.</p>
  
  <p><a href="https://developers.google.com/accounts/docs/OAuth2ServiceAccount" rel="nofollow">https://developers.google.com/accounts/docs/OAuth2ServiceAccount</a></p>