title: Migrating from Google Sign-In and Google Classroom
body: <p>I'm currently trying to add google sign-in support to our educational website. The majority of time users will just sign in with Google, but occasionally teachers need to be able to import pupil rosters from Google Classroom too.  I've got all of this working using the guides from the Classroom developers site (<a href="https://developers.google.com/classroom/quickstart/js" rel="nofollow noreferrer">https://developers.google.com/classroom/quickstart/js</a>). I'm using <a href="https://apis.google.com/js/api.js" rel="nofollow noreferrer">https://apis.google.com/js/api.js</a> to sign users in (gapi.auth2.getAuthInstance().signIn) with just the &quot;profile&quot; scope and then  granting the extra classroom scopes if teachers need them.</p>
  <p>I'm just reading the Migrating to Google Sign-In guide (<a href="https://developers.google.com/identity/gsi/web/guides/migration" rel="nofollow noreferrer">https://developers.google.com/identity/gsi/web/guides/migration</a>) and trying to work out if it applies to us or not.  It's explicitly saying not to use gapi.auth2/gapi.client etc anymore and to use the new Identity Services Library instead, but there's no explanation how to use that to make API calls to Classroom (or any other Google API).  The OAuth 2.0 JS guide (<a href="https://developers.google.com/identity/protocols/oauth2/javascript-implicit-flow" rel="nofollow noreferrer">https://developers.google.com/identity/protocols/oauth2/javascript-implicit-flow</a>) is still saying to use gapi.auth2 etc too.</p>
  <p>So should I be using the new library to sign users in, instead of api.js?</p>
  <p>And if so, am I still supposed to be using gapi.auth2 to make API calls, or should I be using the new library instead somehow?</p>