https://accounts.google.com/o/oauth2/auth?scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fuserinfo.email+https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fuserinfo.profile&redirect_uri=https://my_url&response_type=code&client_id=xxxxx

require('google-api-php-client-2.2.2_PHP54/vendor/autoload.php');
$client = new Google_Client(Constant::PARAMS);
$client->setAccessType('offline');
$client->setRedirectUri('https://my_url');
$accessToken = $client->fetchAccessTokenWithAuthCode($_GET['code']);

https://accounts.google.com/o/oauth2/auth?scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fuserinfo.email+https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fuserinfo.profile&redirect_uri=https://my_url&response_type=code&client_id=xxxxx&state=https://my_url

require('google-api-php-client-2.2.2_PHP54/vendor/autoload.php');
$client = new Google_Client(Constant::PARAMS);
$client->setAccessType('offline');
$client->setRedirectUri($_GET['state']);
$accessToken = $client->fetchAccessTokenWithAuthCode($_GET['code']);