rebase: Bump sigs.k8s.io/controller-runtime from 0.15.1 to 0.16.0

Bumps [sigs.k8s.io/controller-runtime](https://github.com/kubernetes-sigs/controller-runtime) from 0.15.1 to 0.16.0.
- [Release notes](https://github.com/kubernetes-sigs/controller-runtime/releases)
- [Changelog](https://github.com/kubernetes-sigs/controller-runtime/blob/main/RELEASE.md)
- [Commits](https://github.com/kubernetes-sigs/controller-runtime/compare/v0.15.1...v0.16.0)

---
updated-dependencies:
- dependency-name: sigs.k8s.io/controller-runtime
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/sigs.k8s.io/controller-runtime/pkg/metrics/listener.go

@@ -1,52 +0,0 @@
-/*
-Copyright 2018 The Kubernetes Authors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package metrics
-
-import (
-	"fmt"
-	"net"
-
-	logf "sigs.k8s.io/controller-runtime/pkg/internal/log"
-)
-
-var log = logf.RuntimeLog.WithName("metrics")
-
-// DefaultBindAddress sets the default bind address for the metrics listener
-// The metrics is on by default.
-var DefaultBindAddress = ":8080"
-
-// NewListener creates a new TCP listener bound to the given address.
-func NewListener(addr string) (net.Listener, error) {
-	if addr == "" {
-		// If the metrics bind address is empty, default to ":8080"
-		addr = DefaultBindAddress
-	}
-
-	// Add a case to disable metrics altogether
-	if addr == "0" {
-		return nil, nil
-	}
-
-	log.Info("Metrics server is starting to listen", "addr", addr)
-	ln, err := net.Listen("tcp", addr)
-	if err != nil {
-		er := fmt.Errorf("error listening on %s: %w", addr, err)
-		log.Error(er, "metrics server failed to listen. You may want to disable the metrics server or use another port if it is due to conflicts")
-		return nil, er
-	}
-	return ln, nil
-}

vendor/sigs.k8s.io/controller-runtime/pkg/metrics/server/doc.go

@@ -0,0 +1,26 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+/*
+Package server provides the metrics server implementation.
+*/
+package server
+
+import (
+	logf "sigs.k8s.io/controller-runtime/pkg/internal/log"
+)
+
+var log = logf.RuntimeLog.WithName("metrics")

vendor/sigs.k8s.io/controller-runtime/pkg/metrics/server/server.go

@@ -0,0 +1,312 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/http"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+
+	"github.com/go-logr/logr"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"k8s.io/client-go/rest"
+	certutil "k8s.io/client-go/util/cert"
+
+	"sigs.k8s.io/controller-runtime/pkg/certwatcher"
+	"sigs.k8s.io/controller-runtime/pkg/internal/httpserver"
+	"sigs.k8s.io/controller-runtime/pkg/metrics"
+)
+
+const (
+	defaultMetricsEndpoint = "/metrics"
+)
+
+// DefaultBindAddress is the default bind address for the metrics server.
+var DefaultBindAddress = ":8080"
+
+// Server is a server that serves metrics.
+type Server interface {
+	// NeedLeaderElection implements the LeaderElectionRunnable interface, which indicates
+	// the metrics server doesn't need leader election.
+	NeedLeaderElection() bool
+
+	// Start runs the server.
+	// It will install the metrics related resources depending on the server configuration.
+	Start(ctx context.Context) error
+}
+
+// Options are all available options for the metrics.Server
+type Options struct {
+	// SecureServing enables serving metrics via https.
+	// Per default metrics will be served via http.
+	SecureServing bool
+
+	// BindAddress is the bind address for the metrics server.
+	// It will be defaulted to ":8080" if unspecified.
+	// Set this to "0" to disable the metrics server.
+	BindAddress string
+
+	// ExtraHandlers contains a map of handlers (by path) which will be added to the metrics server.
+	// This might be useful to register diagnostic endpoints e.g. pprof.
+	// Note that pprof endpoints are meant to be sensitive and shouldn't be exposed publicly.
+	// If the simple path -> handler mapping offered here is not enough, a new http
+	// server/listener should be added as Runnable to the manager via the Add method.
+	ExtraHandlers map[string]http.Handler
+
+	// FilterProvider provides a filter which is a func that is added around
+	// the metrics and the extra handlers on the metrics server.
+	// This can be e.g. used to enforce authentication and authorization on the handlers
+	// endpoint by setting this field to filters.WithAuthenticationAndAuthorization.
+	FilterProvider func(c *rest.Config, httpClient *http.Client) (Filter, error)
+
+	// CertDir is the directory that contains the server key and certificate. Defaults to
+	// <temp-dir>/k8s-metrics-server/serving-certs.
+	//
+	// Note: This option is only used when TLSOpts does not set GetCertificate.
+	// Note: If certificate or key doesn't exist a self-signed certificate will be used.
+	CertDir string
+
+	// CertName is the server certificate name. Defaults to tls.crt.
+	//
+	// Note: This option is only used when TLSOpts does not set GetCertificate.
+	// Note: If certificate or key doesn't exist a self-signed certificate will be used.
+	CertName string
+
+	// KeyName is the server key name. Defaults to tls.key.
+	//
+	// Note: This option is only used when TLSOpts does not set GetCertificate.
+	// Note: If certificate or key doesn't exist a self-signed certificate will be used.
+	KeyName string
+
+	// TLSOpts is used to allow configuring the TLS config used for the server.
+	// This also allows providing a certificate via GetCertificate.
+	TLSOpts []func(*tls.Config)
+}
+
+// Filter is a func that is added around metrics and extra handlers on the metrics server.
+type Filter func(log logr.Logger, handler http.Handler) (http.Handler, error)
+
+// NewServer constructs a new metrics.Server from the provided options.
+func NewServer(o Options, config *rest.Config, httpClient *http.Client) (Server, error) {
+	o.setDefaults()
+
+	// Skip server creation if metrics are disabled.
+	if o.BindAddress == "0" {
+		return nil, nil
+	}
+
+	// Validate that ExtraHandlers is not overwriting the default /metrics endpoint.
+	if o.ExtraHandlers != nil {
+		if _, ok := o.ExtraHandlers[defaultMetricsEndpoint]; ok {
+			return nil, fmt.Errorf("overriding builtin %s endpoint is not allowed", defaultMetricsEndpoint)
+		}
+	}
+
+	// Create the metrics filter if a FilterProvider is set.
+	var metricsFilter Filter
+	if o.FilterProvider != nil {
+		var err error
+		metricsFilter, err = o.FilterProvider(config, httpClient)
+		if err != nil {
+			return nil, fmt.Errorf("filter provider failed to create filter for the metrics server: %w", err)
+		}
+	}
+
+	return &defaultServer{
+		metricsFilter: metricsFilter,
+		options:       o,
+	}, nil
+}
+
+// defaultServer is the default implementation used for Server.
+type defaultServer struct {
+	options Options
+
+	// metricsFilter is a filter which is added around
+	// the metrics and the extra handlers on the metrics server.
+	metricsFilter Filter
+
+	// mu protects access to the bindAddr field.
+	mu sync.RWMutex
+
+	// bindAddr is used to store the bindAddr after the listener has been created.
+	// This is used during testing to figure out the port that has been chosen randomly.
+	bindAddr string
+}
+
+// setDefaults does defaulting for the Server.
+func (o *Options) setDefaults() {
+	if o.BindAddress == "" {
+		o.BindAddress = DefaultBindAddress
+	}
+
+	if len(o.CertDir) == 0 {
+		o.CertDir = filepath.Join(os.TempDir(), "k8s-metrics-server", "serving-certs")
+	}
+
+	if len(o.CertName) == 0 {
+		o.CertName = "tls.crt"
+	}
+
+	if len(o.KeyName) == 0 {
+		o.KeyName = "tls.key"
+	}
+}
+
+// NeedLeaderElection implements the LeaderElectionRunnable interface, which indicates
+// the metrics server doesn't need leader election.
+func (*defaultServer) NeedLeaderElection() bool {
+	return false
+}
+
+// Start runs the server.
+// It will install the metrics related resources depend on the server configuration.
+func (s *defaultServer) Start(ctx context.Context) error {
+	log.Info("Starting metrics server")
+
+	listener, err := s.createListener(ctx, log)
+	if err != nil {
+		return fmt.Errorf("failed to start metrics server: failed to create listener: %w", err)
+	}
+	// Storing bindAddr here so we can retrieve it during testing via GetBindAddr.
+	s.mu.Lock()
+	s.bindAddr = listener.Addr().String()
+	s.mu.Unlock()
+
+	mux := http.NewServeMux()
+
+	handler := promhttp.HandlerFor(metrics.Registry, promhttp.HandlerOpts{
+		ErrorHandling: promhttp.HTTPErrorOnError,
+	})
+	if s.metricsFilter != nil {
+		log := log.WithValues("path", defaultMetricsEndpoint)
+		var err error
+		handler, err = s.metricsFilter(log, handler)
+		if err != nil {
+			return fmt.Errorf("failed to start metrics server: failed to add metrics filter: %w", err)
+		}
+	}
+	// TODO(JoelSpeed): Use existing Kubernetes machinery for serving metrics
+	mux.Handle(defaultMetricsEndpoint, handler)
+
+	for path, extraHandler := range s.options.ExtraHandlers {
+		if s.metricsFilter != nil {
+			log := log.WithValues("path", path)
+			var err error
+			extraHandler, err = s.metricsFilter(log, extraHandler)
+			if err != nil {
+				return fmt.Errorf("failed to start metrics server: failed to add metrics filter to extra handler for path %s: %w", path, err)
+			}
+		}
+		mux.Handle(path, extraHandler)
+	}
+
+	log.Info("Serving metrics server", "bindAddress", s.options.BindAddress, "secure", s.options.SecureServing)
+
+	srv := httpserver.New(mux)
+
+	idleConnsClosed := make(chan struct{})
+	go func() {
+		<-ctx.Done()
+		log.Info("Shutting down metrics server with timeout of 1 minute")
+
+		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
+		defer cancel()
+		if err := srv.Shutdown(ctx); err != nil {
+			// Error from closing listeners, or context timeout
+			log.Error(err, "error shutting down the HTTP server")
+		}
+		close(idleConnsClosed)
+	}()
+
+	if err := srv.Serve(listener); err != nil && err != http.ErrServerClosed {
+		return err
+	}
+
+	<-idleConnsClosed
+	return nil
+}
+
+func (s *defaultServer) createListener(ctx context.Context, log logr.Logger) (net.Listener, error) {
+	if !s.options.SecureServing {
+		return net.Listen("tcp", s.options.BindAddress)
+	}
+
+	cfg := &tls.Config{ //nolint:gosec
+		NextProtos: []string{"h2"},
+	}
+	// fallback TLS config ready, will now mutate if passer wants full control over it
+	for _, op := range s.options.TLSOpts {
+		op(cfg)
+	}
+
+	if cfg.GetCertificate == nil {
+		certPath := filepath.Join(s.options.CertDir, s.options.CertName)
+		keyPath := filepath.Join(s.options.CertDir, s.options.KeyName)
+
+		_, certErr := os.Stat(certPath)
+		certExists := !os.IsNotExist(certErr)
+		_, keyErr := os.Stat(keyPath)
+		keyExists := !os.IsNotExist(keyErr)
+		if certExists && keyExists {
+			// Create the certificate watcher and
+			// set the config's GetCertificate on the TLSConfig
+			certWatcher, err := certwatcher.New(certPath, keyPath)
+			if err != nil {
+				return nil, err
+			}
+			cfg.GetCertificate = certWatcher.GetCertificate
+
+			go func() {
+				if err := certWatcher.Start(ctx); err != nil {
+					log.Error(err, "certificate watcher error")
+				}
+			}()
+		}
+	}
+
+	// If cfg.GetCertificate is still nil, i.e. we didn't configure a cert watcher, fallback to a self-signed certificate.
+	if cfg.GetCertificate == nil {
+		// Note: Using self-signed certificates here should be good enough. It's just important that we
+		// encrypt the communication. For example kube-controller-manager also uses a self-signed certificate
+		// for the metrics endpoint per default.
+		cert, key, err := certutil.GenerateSelfSignedCertKeyWithFixtures("localhost", []net.IP{{127, 0, 0, 1}}, nil, "")
+		if err != nil {
+			return nil, fmt.Errorf("failed to generate self-signed certificate for metrics server: %w", err)
+		}
+
+		keyPair, err := tls.X509KeyPair(cert, key)
+		if err != nil {
+			return nil, fmt.Errorf("failed to create self-signed key pair for metrics server: %w", err)
+		}
+		cfg.Certificates = []tls.Certificate{keyPair}
+	}
+
+	return tls.Listen("tcp", s.options.BindAddress, cfg)
+}
+
+func (s *defaultServer) GetBindAddr() string {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.bindAddr
+}