$client = new Google_Client();
$client->setAssertionCredentials(new Google_Auth_AssertionCredentials(
SERVICE_EMAIL_MY, // $serviceAccountName
array('https://www.googleapis.com/auth/analytics.readonly'), //.readonly // scope
file_get_contents(KEY_FILE_MY) //privateKey
));
$client->setClientId(CLIENT_ID_MY);
$client->setAccessType('offline_access');
$client->setClassConfig("Google_Http_Request", "disable_gzip", true);