feat(provisioner): add support for warning log de-duplication

Signed-off-by: Niladri Halder <[email protected]>

Author: niladrih

cmd/provisioner-localpv/app/start.go

@@ -2,6 +2,8 @@ package app
 
 import (
 	"context"
+	"github.com/openebs/dynamic-localpv-provisioner/pkg/logger"
+	"k8s.io/client-go/rest"
 	"os"
 	"strings"
 
@@ -23,6 +25,7 @@ var (
 	// localpv provisioner
 	LeaderElectionKey = "LEADER_ELECTION_ENABLED"
 	usage             = cmdName
+	dedupeWarnings    bool
 )
 
 // StartProvisioner will start a new dynamic Host Path PV provisioner
@@ -39,13 +42,24 @@ func StartProvisioner() (*cobra.Command, error) {
 		},
 	}
 
+	cmd.PersistentFlags().BoolVar(&dedupeWarnings, "dedupe-warnings", false, "De-duplicate warning messages")
+
 	return cmd, nil
 }
 
 // Start will initialize and run the dynamic provisioner daemon
 func Start(cmd *cobra.Command) error {
 	klog.Infof("Starting Provisioner...")
 
+	// De-duplicate warning messages, to avoid flooding logs.
+	if dedupeWarnings {
+		rest.SetDefaultWarningHandler(
+			rest.NewWarningWriter(logger.KlogWarner{}, rest.WarningWriterOptions{
+				Deduplicate: true,
+				Color:       false,
+			}),
+		)
+	}
 	// Dynamic Provisioner can run successfully if it can establish
 	// connection to the Kubernetes Cluster. mKube helps with
 	// establishing the connection either via InCluster or

cmd/provisioner-localpv/main.go

@@ -67,6 +67,7 @@ func run() error {
 
 	// Merge all flags from the Cobra Command to the global FlagSet
 	// and Parse them
+	pflag.CommandLine.AddFlagSet(cmd.PersistentFlags())
 	pflag.CommandLine.AddFlagSet(cmd.Flags())
 	pflag.Parse()
 

deploy/helm/charts/templates/deployment.yaml

@@ -50,6 +50,16 @@ spec:
       - name: {{ template "localpv.fullname" . }}
         image: "{{ with .Values.localpv.image.registry | default .Values.global.imageRegistry | trimSuffix "/" }}{{ . }}/{{ end }}{{ .Values.localpv.image.repository }}:{{ .Values.localpv.image.tag }}"
         imagePullPolicy: {{ .Values.localpv.image.pullPolicy }}
+        {{- $args := list }}
+        {{- if .Values.localpv.logging.dedupeWarnings }}
+          {{- $args = append $args "--dedupe-warnings" }}
+        {{- end }}
+        {{- if gt (len $args) 0 }}
+        args:
+        {{- range $args }}
+        - {{ . | quote }}
+        {{- end }}
+        {{- end }}
         resources:
 {{ toYaml .Values.localpv.resources | indent 10 }}
         env:

deploy/helm/charts/values.yaml

@@ -40,6 +40,9 @@ localpv:
     ## Labels to be added to localpv provisioner deployment pods
   podLabels:
     name: openebs-localpv-provisioner
+  logging:
+    # Disable duplicate warning messages
+    dedupeWarnings: false
   healthCheck:
     initialDelaySeconds: 30
     periodSeconds: 60

pkg/logger/logger.go

@@ -35,13 +35,22 @@ var (
 	loggerKillSwitch     = make(chan struct{})
 )
 
+// KlogWriter writes to Klog's Info stream.
 type KlogWriter struct{}
 
 func (k KlogWriter) Write(data []byte) (n int, err error) {
 	klog.Info(string(data))
 	return len(data), nil
 }
 
+// KlogWarner writes to Klog's Warning stream.
+type KlogWarner struct{}
+
+func (w KlogWarner) Write(data []byte) (n int, err error) {
+	klog.Warning(string(data))
+	return len(data), nil
+}
+
 // This needs to be set correctly to the default log flush duration
 // in case it is not equal to KLOG_FLUSH_INTERVAL.
 // This sets the default flush interval for logs