Загрузка файлов на Google Drive с использованием переполнения стека

Я пытаюсь загрузить файл на Google Диск с помощью Php, но получаю следующее сообщение об ошибке

Неустранимая ошибка: необработанное исключение «Google_Service_Exception» с сообщением «Ошибка вызова POST https://www.googleapis.com/upload/drive/v2/files?uploadType=media: (401) Требуется вход в систему ‘в C: \ xampp \ htdocs \ Testing \ src \ Google \ Http \ REST.php: 79

Вот мой код:

DEFINE("TESTFILE", 'testfile-small.txt');//Creating a file
if (true || !file_exists(TESTFILE)) {
$fh = fopen(TESTFILE, 'w');
echo "File Created";
fseek($fh, 1024 * 1024);
fwrite($fh, "!", 1);
fclose($fh);
}
//Setting the Authentication Properties
$client_id = 'x-x-x-';      //These properties generated using GoogleApisConsole
$client_secret = 'x-x-x-';
$redirect_uri = 'x-x-x ';
$client = new Google_Client();
$client->setClientId($client_id);
$client->setClientSecret($client_secret);
$client->setRedirectUri($redirect_uri);
//$client->setDeveloperKey('AIzaSyAMOwFvprof_tCGdfiaeoUoYI5BfgGyO7I');
$client->setApplicationName("My Application");
$client->addScope("https://www.googleapis.com/auth/drive.file");//Adding Scope

$service = new Google_Service_Drive($client);
//Checking for User Session
if (isset($_REQUEST['logout'])) {
echo "In first if";
unset($_SESSION['upload_token']);
}
if (isset($_GET['code'])) {
$client->authenticate($_GET['code']);
$_SESSION['upload_token'] = $client->getAccessToken();
$redirect = 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['PHP_SELF'];
header('Location: ' . filter_var($redirect, FILTER_SANITIZE_URL));
}
if (isset($_SESSION['upload_token']) && $_SESSION['upload_token']) {
$client->setAccessToken($_SESSION['upload_token']);
echo "In second if";
if ($client->isAccessTokenExpired()) {
echo "In third if";
unset($_SESSION['upload_token']);
}
} else {
echo "In else";
$authUrl = $client->createAuthUrl();
}

// This is uploading a file directly, with no metadata associated.
//if ($client->getAccessToken()) {
echo "Now i can send file";
// This is uploading a file directly, with no metadata associated.
$file = new Google_Service_Drive_DriveFile();
echo "First Step";
$result = $service->files->insert(
$file,
array(
'data' => file_get_contents(TESTFILE),
'mimeType' => 'application/octet-stream',
'uploadType' => 'media'
)
);

// Now lets try and send the metadata as well using multipart!
$file = new Google_Service_Drive_DriveFile();
Echo "last problem";
$file->setTitle("Hello World!");
$result2 = $service->files->insert(
$file,
array(
'data' => file_get_contents(TESTFILE),
'mimeType' => 'application/octet-stream',
'uploadType' => 'multipart'
)
);
//}
echo ($client->getAccessToken());
echo "File Upload - Uploading a small file";

?>

Пожалуйста, помогите мне.