'Get online free WWNs.
If no new ports connected, return an empty list.'

def get_online_free_wwns(self):

    url = '/fc_initiator?ISFREE=true&range=[0-8191]'
    result = self.call(url, None, 'GET')
    msg = _('Get    connected    free    FC    wwn    error.')
    self._assert_rest_result(result, msg)
    wwns = []
    if ('data' in result):
        for item in result['data']:
            if (item['RUNNINGSTATUS'] == constants.FC_INIT_ONLINE):
                wwns.append(item['ID'])
    return wwns
