Reactor Netty using context-aware HTTP server metrics

TestProject.java

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketAddress;
import java.time.Duration;

import reactor.core.publisher.Mono;
import reactor.netty.Connection;
import reactor.netty.ConnectionObserver;
import reactor.netty.http.server.ContextAwareHttpServerMetricsRecorder;
import reactor.netty.http.server.HttpServer;
import reactor.util.context.Context;
import reactor.util.context.ContextView;

public class TestProject {
    public static void main(String[] args) throws IOException {
        var server = HttpServer.create()
                .metrics(true, ServerMetricsReporter::new)
                .childObserve(new ConnectionObserver() {
                    @Override
                    public void onStateChange(Connection connection, State newState) { }

                    @Override
                    public Context currentContext() {
                        return Context.of("Hello", "World");
                    }
                })
                .observe(new ConnectionObserver() {
                    @Override
                    public void onStateChange(Connection connection, State newState) { }

                    @Override
                    public Context currentContext() {
                        return Context.of("Hello", "There");
                    }
                })
                .route(routes -> routes
                        .get("/hello", (req, res) -> res
                                .status(200)
                                .sendString(Mono.just("Hello!")))
                )
                .bindAddress(() -> new InetSocketAddress(InetAddress.getLoopbackAddress(), 8080))
                .bindNow();

        try {
            System.out.println("Press enter to quit.");
            System.in.read();
        } finally {
            server.disposeNow();
        }
    }
}

final class ServerMetricsReporter extends ContextAwareHttpServerMetricsRecorder {
    @Override
    public void recordDataReceivedTime(ContextView contextView, String uri, String method, Duration time) {

    }

    @Override
    public void recordDataSentTime(ContextView contextView, String uri, String method, String status, Duration time) {

    }

    @Override
    public void recordResponseTime(ContextView contextView, String uri, String method, String status, Duration time) {
        // following the stack trace shows that `HttpServerOperations.listener` is `ServerTransport.ChildObserver`
        // which does not implement `currentContext` thus falls to the default implementation that returns `Context.empty()`
        assert contextView.hasKey("Hello");
    }

    @Override
    public void incrementErrorsCount(ContextView contextView, SocketAddress remoteAddress, String uri) {

    }

    @Override
    public void recordDataReceived(ContextView contextView, SocketAddress remoteAddress, String uri, long bytes) {

    }

    @Override
    public void recordDataSent(ContextView contextView, SocketAddress remoteAddress, String uri, long bytes) {

    }

    @Override
    public void incrementErrorsCount(ContextView contextView, SocketAddress remoteAddress) {

    }

    @Override
    public void recordConnectTime(ContextView contextView, SocketAddress remoteAddress, Duration time, String status) {

    }

    @Override
    public void recordDataReceived(ContextView contextView, SocketAddress remoteAddress, long bytes) {

    }

    @Override
    public void recordDataSent(ContextView contextView, SocketAddress remoteAddress, long bytes) {

    }

    @Override
    public void recordTlsHandshakeTime(ContextView contextView, SocketAddress remoteAddress, Duration time, String status) {

    }

    @Override
    public void recordResolveAddressTime(SocketAddress remoteAddress, Duration time, String status) {

    }
}