def nxDataGetSignals(data):
    """
    Get NXdata signals (default signal first)

    :param h5py.Group data:
    :returns list(str): signal names (default first)
    """
    signal = data.attrs.get('signal', None)
    auxsignals = data.attrs.get('auxiliary_signals', None)
    if signal is None:
        lst = []
    else:
        lst = [signal]
    if auxsignals is not None:
        lst += auxsignals.tolist()
    return lst
