public function __construct(Database $db, string $channel = '')
{
parent::__construct($db);
$this->channel = $channel;
$channelConfig = \Airship\loadJSON(ROOT . '/config/channels.json');
$this->channelPublicKey = new SignaturePublicKey(\Sodium\hex2bin($channelConfig[$channel]['publickey']));
$this->urls = $channelConfig[$channel]['urls'];
}