auth/internal/testdata/imp_universe_domain.json

{
    "service_account_impersonation_url": "https://iamcredentials.googleapis.com/v1/projects/-/serviceAccounts/sa3@developer.gserviceaccount.com:generateAccessToken",
    "delegates": [
        "sa1@developer.gserviceaccount.com",
        "sa2@developer.gserviceaccount.com"
    ],
    "source_credentials": {
        "type": "service_account",
        "project_id": "fake_project",
        "private_key_id": "89asd789789uo473454c47543",
        "private_key": "fake",
        "client_email": "sa@fake_project.iam.gserviceaccount.com",
        "client_id": "gopher",
        "auth_uri": "https://accounts.google.com/o/oauth2/auth",
        "token_uri": "https://oauth2.googleapis.com/token"
    },
    "type": "impersonated_service_account",
    "universe_domain": "example.com"
}