def _is_raw_pubsub_payload(request_data) -> bool:
    """Does the given request body match the schema of a unmarshalled Pub/Sub request"""
    return (
        request_data is not None
        and "context" not in request_data
        and "subscription" in request_data
        and "message" in request_data
        and "data" in request_data["message"]
        and "messageId" in request_data["message"]
    )