google login authentication api code example
Example 1: login by google api
<meta name="google-signin-client_id" content="YOUR_CLIENT_ID.apps.googleusercontent.com">
Example 2: login by google api
<a href="#" onclick="signOut();">Sign out</a><script> function signOut() { var auth2 = gapi.auth2.getAuthInstance(); auth2.signOut().then(function () { console.log('User signed out.'); }); }</script>