谷歌驱动服务帐户和“请求中的未经授权的客户端或范围"

The p12 certificate and user values are stored on the server. All "ini" files have the same structure of values, client_id, client_email, scope and query filter. In all cases the only item that changes between the files is the client_id and client_email.

我的代码如下:

    <?php

 include (__DIR__ . "/google-api-php-client/autoload.php");

 google_api_php_client_autoload("Google_Auth_AssertionCredentials");
 google_api_php_client_autoload("Google_Client");
 google_api_php_client_autoload("Google_Service_Drive");
 google_api_php_client_autoload("Google_Service_OAuth2");

 $type = $_GET['type'];
 $path = __DIR__ . "/secure/";
 $certificate = $path . $type . ".p12";
 $ini_path = $path . $type . ".ini";

 $ini = parse_ini_file($ini_path);
 $service_scope = $ini['scope'];
 $service_account_id = $ini['id'];
 $service_account_email = $ini['email'];
 $service_query = $ini['q'];

 $service_account_key = file_get_contents($certificate);
 $credentials = new Google_Auth_AssertionCredentials(
  $service_account_email,
  array($service_scope),
  $service_account_key
 );
 $credentials -> sub = $service_account_email;

 $google_client = new Google_Client();

 $google_client -> setAssertionCredentials($credentials);
 if ($google_client -> getAuth() -> isAccessTokenExpired()) {
  $google_client -> getAuth() -> refreshTokenWithAssertion(); **//FAILS HERE**
 }  

 $drive = new Google_Service_Drive($google_client);

 $result = array();
 $pageToken = NULL;

 do {
  try {
   $parameters = array();
   if ($pageToken) {
    $parameters['pageToken'] = $pageToken;
   }
   $parameters['q'] = $service_query;

   $files = $drive -> files -> listFiles($parameters);

   $result = array_merge($result, $files -> getItems());
   $pageToken = $files -> getNextPageToken();
  } catch (Exception $e) {
   print "An error occurred: " . $e -> getMessage();
   $pageToken = NULL;
  }
 } while ($pageToken);

 echo json_encode($result) . "
";
?>

每个ini文件的结构如下

id="35{code}.apps.googleusercontent.com"
email="35{code}@developer.gserviceaccount.com"
scope="https://www.googleapis.com/auth/drive.readonly"
q="mimeType != 'application/vnd.google-apps.folder'"