func (settings *HTTPTransportSettings) httpRoundTripper(
	tls *tlscommon.TLSConfig,
	dialer, tlsDialer transport.Dialer,
	opts ...TransportOption,
) *http.Transport {
	t := http.DefaultTransport.(*http.Transport).Clone()

// DefaultTransport is the default implementation of Transport and is
// used by DefaultClient. It establishes network connections as needed
// and caches them for reuse by subsequent calls. It uses HTTP proxies
// as directed by the environment variables HTTP_PROXY, HTTPS_PROXY
// and NO_PROXY (or the lowercase versions thereof).
var DefaultTransport RoundTripper = &Transport{
	Proxy: ProxyFromEnvironment,
	DialContext: defaultTransportDialContext(&net.Dialer{
		Timeout:   30 * time.Second,
		KeepAlive: 30 * time.Second,
	}),
	ForceAttemptHTTP2:     true,
	MaxIdleConns:          100,
	IdleConnTimeout:       90 * time.Second,
	TLSHandshakeTimeout:   10 * time.Second,
	ExpectContinueTimeout: 1 * time.Second,
}

func (opts WithKeepaliveSettings) applyTransport(_ *HTTPTransportSettings, t *http.Transport) {
	t.DisableKeepAlives = opts.Disable
	if opts.IdleConnTimeout != 0 {
		t.IdleConnTimeout = opts.IdleConnTimeout
	}