How to use Application Default Credentials on CGP Cloud Run for Google Drive API

Step 1. Create service account.

Step 2. Set the service account to Cloud Run security settings.

Step 3. Share a Google Drive folder (or a file) to the service account email address.

• see also :
  • https://developers.google.com/identity/protocols/application-default-credentials
  • (for PHP) https://github.com/googleapis/google-api-php-client