Add pprof flag (#703)

* add optional pprof to logging-operator
* add extraArgs to chart

Author: tarokkk

Makefile

@@ -100,7 +100,7 @@ manager: generate fmt vet
 
 # Run against the configured Kubernetes cluster in ~/.kube/config
 run: generate fmt vet
-	go run ./main.go --verbose
+	go run ./main.go --verbose --pprof
 
 # remote debug
 debug: manager

charts/logging-operator/templates/deployment.yaml

@@ -34,6 +34,9 @@ spec:
       containers:
         - name: {{ .Chart.Name }}
           image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
+          args: {{ range .Values.extraArgs }}
+            - {{ . -}}
+            {{ end }}
           imagePullPolicy: {{ .Values.image.pullPolicy }}
           resources:
             {{- toYaml .Values.resources | nindent 12 }}

charts/logging-operator/values.yaml

@@ -9,6 +9,7 @@ image:
   tag: 3.9.1
   pullPolicy: IfNotPresent
 
+extraArgs: []
 imagePullSecrets: []
 nameOverride: ""
 fullnameOverride: ""

main.go

@@ -17,6 +17,8 @@ package main
 import (
 	"context"
 	"flag"
+	"net/http"
+	"net/http/pprof"
 	"os"
 	"strings"
 
@@ -54,11 +56,13 @@ func main() {
 	var metricsAddr string
 	var enableLeaderElection bool
 	var verboseLogging bool
+	var enableprofile bool
 
 	flag.StringVar(&metricsAddr, "metrics-addr", ":8080", "The address the metric endpoint binds to.")
 	flag.BoolVar(&enableLeaderElection, "enable-leader-election", false,
 		"Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.")
 	flag.BoolVar(&verboseLogging, "verbose", false, "Enable verbose logging")
+	flag.BoolVar(&enableprofile, "pprof", false, "enable pprof")
 	flag.Parse()
 
 	ctx := context.Background()
@@ -81,6 +85,15 @@ func main() {
 		os.Exit(1)
 	}
 
+	if enableprofile {
+		setupLog.Info("enabling pprof")
+		err = mgr.AddMetricsExtraHandler("/debug/pprof/", http.HandlerFunc(pprof.Index))
+		if err != nil {
+			setupLog.Error(err, "unable to attach pprof to webserver")
+			os.Exit(1)
+		}
+	}
+
 	if err := detectContainerRuntime(ctx, mgr.GetAPIReader()); err != nil {
 		setupLog.Error(err, "failed to detect container runtime")
 		os.Exit(1)