Auto refresh token in session on google api

refresh_session.js

function refreshSession() {
  if (!gapi.auth2.getAuthInstance().currentUser.get().isSignedIn()) {
    return;
  }
  var authResponse = gapi.auth2.getAuthInstance().currentUser.get().getAuthResponse();
  if (authResponse.expires_at - Date.now() < 60000) {
    gapi.auth2.getAuthInstance().currentUser.get().reloadAuthResponse()
    .then(() => {
      setTimeout(refreshSession, 5000); // 5s 
    })
    .catch(error => {
      setTimeout(refreshSession, 3000); // 3s
    });
  } else {
    setTimeout(refreshSession, 1000); // 1s
  }
}

### Credit-don't remember.