gc

$scopes = array('https://www.googleapis.com/auth/calendar', 'https://www.googleapis.com/auth/calendar.readonly');
$credentials = new Google_Auth_AssertionCredentials(
  $client_email,
  $scopes,
  $private_key,
  'notasecret'
);
$client = new Google_Client();
$client->setAssertionCredentials($credentials);
if ($client->getAuth()->isAccessTokenExpired()) {
  $client->getAuth()->refreshTokenWithAssertion();
}
//only get events for today
$today = date('H:i');
$current_time = strtotime($today);
$params = array(
  'singleEvents' => false,
  'timeMin' => (new DateTime())->format(DateTime::RFC3339),
  'timeMax' => (new DateTime())->add(new DateInterval('P1D'))->format(DateTime::RFC3339)
);