Go client 如何自定义 dns 解析以及跳过 https 证书验证

var (
    dialer = &net.Dialer{}
)
type DnsOverride struct {
    Domain string `json:"domain"`
    Ip     string `json:"ip"`
}
func newTr(overrides []DnsOverride, skipTlsVerify bool) *http.Transport {
    tr := &http.Transport{
        TLSClientConfig: &tls.Config{InsecureSkipVerify: skipTlsVerify},
    }
    if len(overrides) == 0 {
        return tr
    }
    tr.DialContext = func(ctx context.Context, network, addr string) (net.Conn, error) {
        host, port, err := net.SplitHostPort(addr)
        if err != nil {
            return dialer.DialContext(ctx, network, addr)
        }
        for _, override := range overrides {
            if host == override.Domain {
                addr = override.Ip + ":" + port
                break
            }
        }
        return dialer.DialContext(ctx, network, addr)
    }
    return tr
}