✨ Add httpserver.Server and pkg/debug for pprof support

pkg/debug/register.go

@@ -0,0 +1,61 @@
+/*
+Copyright 2020 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 debug
+
+import (
+	"net/http/pprof"
+
+	"sigs.k8s.io/controller-runtime/pkg/httpserver"
+)
+
+// Options use to provide configuration option
+type Options struct {
+	CmdLine bool
+	Profile bool
+	Symbol  bool
+	Trace   bool
+}
+
+// DefaultOptions returns default options configuration
+func DefaultOptions() *Options {
+	return &Options{
+		CmdLine: true,
+		Profile: true,
+		Symbol:  true,
+		Trace:   true,
+	}
+}
+
+// Register use to register the different debug endpoint
+func Register(mux httpserver.Server, options *Options) {
+	mux.HandleFunc("/debug/pprof/", pprof.Index)
+	if options == nil {
+		options = DefaultOptions()
+	}
+	if options.CmdLine {
+		mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	}
+	if options.Profile {
+		mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	}
+	if options.Symbol {
+		mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	}
+	if options.Trace {
+		mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+	}
+}

pkg/httpserver/interface.go

@@ -0,0 +1,31 @@
+/*
+Copyright 2020 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 httpserver
+
+import (
+	"net/http"
+
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+)
+
+// Server inferface for the http server
+// Allows to register http.Hander and http.HandlerFunc
+type Server interface {
+	manager.Runnable
+	Handle(path string, handler http.Handler)
+	HandleFunc(path string, handlerFunc http.HandlerFunc)
+}

pkg/httpserver/runner.go

@@ -0,0 +1,103 @@
+/*
+Copyright 2020 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 httpserver
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/http"
+
+	logf "sigs.k8s.io/controller-runtime/pkg/internal/log"
+)
+
+var log = logf.RuntimeLog.WithName("httpserver")
+
+// DefaultBindAddress sets the default bind address for the HTTP server listener
+var DefaultBindAddress = ":8080"
+
+// Options use to provides Runner creation options
+type Options struct {
+	BindAddress string
+}
+
+// server HTTP debug server
+type server struct {
+	bindAddress string
+
+	mux *http.ServeMux
+}
+
+// New returns new Runner instance
+func New(options Options) Server {
+	return &server{
+		bindAddress: options.BindAddress,
+		mux:         http.NewServeMux(),
+	}
+}
+
+// Handle registers the handler for the given pattern.
+// If a handler already exists for pattern, Handle panics.
+func (s *server) Handle(path string, handler http.Handler) {
+	s.mux.Handle(path, handler)
+}
+
+// HandleFunc registers the handler function for the given pattern
+// in the DefaultServeMux.
+// The documentation for ServeMux explains how patterns are matched.
+func (s *server) HandleFunc(path string, handlerFunc http.HandlerFunc) {
+	s.mux.HandleFunc(path, handlerFunc)
+}
+
+// Start use to start the HTTP server
+func (s *server) Start(stop <-chan struct{}) error {
+	listener, err := newListener(s.bindAddress)
+	if err != nil {
+		return err
+	}
+	server := http.Server{
+		Handler: s.mux,
+	}
+	// Run the server
+	go func() {
+		log.Info("starting http server")
+		if err := server.Serve(listener); err != nil && err != http.ErrServerClosed {
+			log.Error(err, "http server error")
+		}
+	}()
+
+	// Shutdown the server when stop is close
+	<-stop
+	return server.Shutdown(context.Background())
+}
+
+// newListener creates a new TCP listener bound to the given address.
+func newListener(addr string) (net.Listener, error) {
+	if addr == "" {
+		// If the http server bind address is empty, default to ":8080"
+		addr = DefaultBindAddress
+	}
+
+	log.Info("debug server is starting to listen", "addr", addr)
+	ln, err := net.Listen("tcp", addr)
+	if err != nil {
+		er := fmt.Errorf("error listening on %s: %v", addr, err)
+		log.Error(er, "debug server failed to listen. You may want to disable the debug server or use another port if it is due to conflicts")
+		return nil, er
+	}
+	return ln, nil
+}

pkg/metrics/register.go

@@ -0,0 +1,32 @@
+/*
+Copyright 2020 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 (
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+
+	"sigs.k8s.io/controller-runtime/pkg/httpserver"
+)
+
+// Register used to register Metrics handler in the http server
+func Register(mux httpserver.Server) {
+	var metricsPath = "/metrics"
+	handler := promhttp.HandlerFor(Registry, promhttp.HandlerOpts{
+		ErrorHandling: promhttp.HTTPErrorOnError,
+	})
+	mux.Handle(metricsPath, handler)
+}