[cli] improve runtime and reverse proxy logging

Initialize structured logger for runtime components with stderr output.
Route reverse proxy error logs through slog, downgrading noisy client
disconnect errors (EOF, broken pipe, context canceled) to debug level.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: dilyevsky

pkg/cmd/run/cmd.go

@@ -8,6 +8,7 @@ import (
 
 	configv1alpha1 "github.com/apoxy-dev/apoxy/api/config/v1alpha1"
 	"github.com/apoxy-dev/apoxy/config"
+	"github.com/apoxy-dev/apoxy/pkg/log"
 )
 
 var runCmd = &cobra.Command{
@@ -36,6 +37,9 @@ Components are defined under runtime.components in the config. Example:
 		if err != nil {
 			return fmt.Errorf("failed to load config: %w", err)
 		}
+		if err := initRuntimeLogger(cfg); err != nil {
+			return fmt.Errorf("failed to initialize runtime logger: %w", err)
+		}
 		if cfg.Runtime == nil || len(cfg.Runtime.Components) == 0 {
 			return fmt.Errorf("no runtime components configured\n\n"+
 				"Add a runtime section to your config (%s):\n\n"+
@@ -104,6 +108,16 @@ func Cmd() *cobra.Command {
 	return runCmd
 }
 
+func initRuntimeLogger(cfg *configv1alpha1.Config) error {
+	opts := []log.Option{log.WithStderrOnly()}
+	if config.Verbose || cfg.Verbose {
+		opts = append(opts, log.WithDevMode(), log.WithLevel(log.DebugLevel))
+	} else {
+		opts = append(opts, log.WithLevel(log.InfoLevel))
+	}
+	return log.Init(opts...)
+}
+
 func resolveKubeMirrorConfig(in *configv1alpha1.KubeMirrorConfig) *configv1alpha1.KubeMirrorConfig {
 	out := in.DeepCopy()
 	if out.Mirror == "" {

pkg/kube-controller/apiserviceproxy/cloud.go

@@ -115,6 +115,7 @@ func resolveBaseAPIProxyHost(apiHost string) string {
 
 func newCloudReverseProxy(remote *url.URL) *httputil.ReverseProxy {
 	proxy := httputil.NewSingleHostReverseProxy(remote)
+	proxy.ErrorLog = newReverseProxyErrorLogger()
 	originalDirector := proxy.Director
 	proxy.Director = func(req *http.Request) {
 		originalDirector(req)

pkg/kube-controller/apiserviceproxy/kubeconfig.go

@@ -37,6 +37,7 @@ func (p *APIServiceProxy) configureKubeconfigProxy(ctx context.Context) error {
 			req.Host = hostURL.Host
 		},
 		Transport: transport,
+		ErrorLog:  newReverseProxyErrorLogger(),
 	}
 
 	cert, _, _, caBundle, err := generateServingCertificate(p.opts.ServiceName, p.opts.Namespace)

pkg/kube-controller/apiserviceproxy/reverseproxy.go

@@ -0,0 +1,27 @@
+package apiserviceproxy
+
+import (
+	"log"
+	"log/slog"
+	"strings"
+)
+
+type reverseProxyErrorLogWriter struct{}
+
+func (reverseProxyErrorLogWriter) Write(p []byte) (int, error) {
+	msg := strings.TrimSpace(string(p))
+	switch {
+	case strings.Contains(msg, "httputil: ReverseProxy read error during body copy: unexpected EOF"),
+		strings.Contains(msg, "httputil: ReverseProxy read error during body copy: context canceled"),
+		strings.Contains(msg, "httputil: ReverseProxy read error during body copy: write: broken pipe"),
+		strings.Contains(msg, "httputil: ReverseProxy read error during body copy: broken pipe"):
+		slog.Debug("reverse proxy client disconnected", slog.String("message", msg))
+	default:
+		slog.Warn("reverse proxy internal error", slog.String("message", msg))
+	}
+	return len(p), nil
+}
+
+func newReverseProxyErrorLogger() *log.Logger {
+	return log.New(reverseProxyErrorLogWriter{}, "", 0)
+}