Google服务帐户授权

Question

我尝试使用google-api-php-client客户端使用服务帐户连接到Google云端硬盘。如支持人员所述，所有帐户设置均正确设置。但是我有错误{“ error”：“ invalid_grant”}

include_once __DIR__ . '/vendor/autoload.php';
include_once __DIR__ . '/vendor/google/apiclient/examples/templates/base.php';

$client = new Google_Client();
if ($credentials_file = checkServiceAccountCredentialsFile()) {
 $client->setAuthConfig($credentials_file);
} elseif (getenv('GOOGLE_APPLICATION_CREDENTIALS')) {
  $client->useApplicationDefaultCredentials();
} else {
  echo missingServiceAccountDetailsWarning();
  return;
}  
$client->setApplicationName('name-server-google-suite-drive');
$client->addScope(Google_Service_Drive::DRIVE);
$client->setSubject('account_email');

我正在尝试创建Google客户端，但没有授权。在客户端设置中还应该指定什么才能授权工作？