@Nullable
    private static String getAuthority0(RequestContext ctx, HttpHeaders headers) {
        String authority = headers.get(HttpHeaderNames.AUTHORITY);
        if (authority != null) {
            final Pattern portPattern = ctx.sessionProtocol().isTls() ? PORT_443 : PORT_80;
            final Matcher m = portPattern.matcher(authority);
            if (m.find()) {
                authority = authority.substring(0, m.start());
            }
            return authority;
        }

        return null;
    }
{@code "tls.proto"} - the current {@linkplain SSLSession#getProtocol() TLS protocol}.
Unavailable if TLS handshake is not finished or the connection is not a TLS connection, such as
{@code "TLSv1.2"}.
core/src/main/java/com/linecorp/armeria/common/logging/BuiltInProperty.java