go: 获取所有网卡名和IP地址

func GetClientIp(filter string) (string, error) {
    interfaces, err := net.Interfaces()
    if err != nil {
        return "", err
    }
    nameIPS := map[string]string{}
    names := []string{}
    for _, i := range interfaces {
        name := i.Name
        addrs, err := i.Addrs()
        if err != nil {
            panic(err)
        }
        // handle err
        for _, addr := range addrs {
            var (
                ip net.IP
            )
            switch v := addr.(type) {
            case *net.IPNet:
                ip = v.IP
            case *net.IPAddr:
                ip = v.IP
            }
            if filter == "" || strings.Contains(name, filter) {
                names = append(names, name)
                nameIPS[name] = ip.String()
            }
        }
    }
    sort.Strings(names)
    if len(names) == 0 {
        return "", errors.New("can not find the client ip address ")
    }
    logrus.Infof("GetClientIP ips:%v", nameIPS)
    return nameIPS[names[0]], nil
}