feat(controller): enable pprof profiling support

cmd/rollouts-controller/main.go

@@ -2,6 +2,7 @@
 
 import (
 	"fmt"
+	"net/http"
 	"os"
 	"strings"
 	"time"
@@ -79,6 +80,7 @@
 		printVersion                   bool
 		selfServiceNotificationEnabled bool
 		controllersEnabled             []string
+		pprofAddress                   string
 	)
 	electOpts := controller.NewLeaderElectionOptions()
 	var command = cobra.Command{
@@ -204,6 +206,11 @@
 			ingressWrapper, err := ingressutil.NewIngressWrapper(mode, kubeClient, kubeInformerFactory)
 			checkError(err)
 
+			if pprofAddress != "" {
+				mux := controller.NewPProfServer()
+				go func() { log.Println(http.ListenAndServe(pprofAddress, mux)) }()
+			}
+
 			var cm *controller.Manager
 
 			enabledControllers, err := getEnabledControllers(controllersEnabled)
@@ -310,6 +317,7 @@
 	command.Flags().DurationVar(&electOpts.LeaderElectionRetryPeriod, "leader-election-retry-period", controller.DefaultLeaderElectionRetryPeriod, "The duration the clients should wait between attempting acquisition and renewal of a leadership. This is only applicable if leader election is enabled.")
 	command.Flags().BoolVar(&selfServiceNotificationEnabled, "self-service-notification-enabled", false, "Allows rollouts controller to pull notification config from the namespace that the rollout resource is in. This is useful for self-service notification.")
 	command.Flags().StringSliceVar(&controllersEnabled, "controllers", nil, "Explicitly specify the list of controllers to run, currently only supports 'analysis', eg. --controller=analysis. Default: all controllers are enabled")
+	command.Flags().StringVar(&pprofAddress, "enable-pprof-address", "", "Enable pprof profiling on controller by providing a server address.")
 	return &command
 }
 

controller/profiling.go

@@ -0,0 +1,24 @@
+package controller
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/pprof"
+)
+
+const (
+	ProfilingPath = "/debug/pprof"
+)
+
+// NewPProfServer returns a new pprof server to gather runtime profiling data
+func NewPProfServer() *http.ServeMux {
+	mux := http.NewServeMux()
+
+	mux.HandleFunc(ProfilingPath, pprof.Index)
+	mux.HandleFunc(fmt.Sprintf("%s/cmdline", ProfilingPath), pprof.Cmdline)
+	mux.HandleFunc(fmt.Sprintf("%s/profile", ProfilingPath), pprof.Profile)
+	mux.HandleFunc(fmt.Sprintf("%s/symbol", ProfilingPath), pprof.Symbol)
+	mux.HandleFunc(fmt.Sprintf("%s/trace", ProfilingPath), pprof.Trace)
+
+	return mux
+}