@Override
    public ProxyConfig select(SessionProtocol protocol, Endpoint endpoint) {
        requireNonNull(protocol, "protocol");
        requireNonNull(endpoint, "endpoint");
        final List<Proxy> proxies = proxySelector.select(toUri(protocol, endpoint));
        if (proxies == null || proxies.isEmpty()) {
            return ProxyConfig.direct();
        }

        final Proxy proxy = proxies.get(0);
        if (logger.isDebugEnabled() && proxies.size() > 1) {
            logger.debug("Using the first proxy <{}> of <{}>.", proxy, proxies);
        }
        return toProxyConfig(proxy);
    }
Converts {@link SessionProtocol}, {@link Endpoint} to a uri without serialization format.
core/src/main/java/com/linecorp/armeria/client/proxy/WrappingProxyConfigSelector.java