Merge pull request #6493 from mszacillo/descheduler-structured-logs

Add JSON logging support for Karmada descheduler component

Author: karmada-bot

artifacts/deploy/karmada-descheduler.yaml

@@ -39,6 +39,7 @@ spec:
             - --scheduler-estimator-ca-file=/etc/karmada/pki/scheduler-estimator-client/ca.crt
             - --scheduler-estimator-cert-file=/etc/karmada/pki/scheduler-estimator-client/tls.crt
             - --scheduler-estimator-key-file=/etc/karmada/pki/scheduler-estimator-client/tls.key
+            - --logging-format=json
             - --v=4
           livenessProbe:
             httpGet:

cmd/descheduler/app/descheduler.go

@@ -33,12 +33,15 @@ import (
 	"k8s.io/client-go/tools/leaderelection/resourcelock"
 	"k8s.io/client-go/util/flowcontrol"
 	cliflag "k8s.io/component-base/cli/flag"
+	"k8s.io/component-base/logs"
+	logsv1 "k8s.io/component-base/logs/api/v1"
 	"k8s.io/component-base/term"
 	"k8s.io/klog/v2"
 	ctrlmetrics "sigs.k8s.io/controller-runtime/pkg/metrics"
 
 	"github.com/karmada-io/karmada/cmd/descheduler/app/options"
 	"github.com/karmada-io/karmada/pkg/descheduler"
+	"github.com/karmada-io/karmada/pkg/features"
 	karmadaclientset "github.com/karmada-io/karmada/pkg/generated/clientset/versioned"
 	versionmetrics "github.com/karmada-io/karmada/pkg/metrics"
 	"github.com/karmada-io/karmada/pkg/sharedcli"
@@ -80,12 +83,22 @@ const (
 
 // NewDeschedulerCommand creates a *cobra.Command object with default parameters
 func NewDeschedulerCommand(ctx context.Context) *cobra.Command {
+	logConfig := logsv1.NewLoggingConfiguration()
+	fss := cliflag.NamedFlagSets{}
+
+	logsFlagSet := fss.FlagSet("logs")
+	logs.AddFlags(logsFlagSet, logs.SkipLoggingConfigurationFlags())
+	logsv1.AddFlags(logConfig, logsFlagSet)
+	klogflag.Add(logsFlagSet)
+
+	genericFlagSet := fss.FlagSet("generic")
 	opts := options.NewOptions()
+	opts.AddFlags(genericFlagSet)
 
 	cmd := &cobra.Command{
 		Use: names.KarmadaDeschedulerComponentName,
 		Long: `The karmada-descheduler evicts replicas from member clusters
-if they are failed to be scheduled for a period of time. It relies on 
+if they are failed to be scheduled for a period of time. It relies on
 karmada-scheduler-estimator to get replica status.`,
 		RunE: func(_ *cobra.Command, _ []string) error {
 			// validate options
@@ -105,17 +118,15 @@ karmada-scheduler-estimator to get replica status.`,
 			}
 			return nil
 		},
+		PersistentPreRunE: func(_ *cobra.Command, _ []string) error {
+			if err := logsv1.ValidateAndApply(logConfig, features.FeatureGate); err != nil {
+				return err
+			}
+			logs.InitLogs()
+			return nil
+		},
 	}
 
-	fss := cliflag.NamedFlagSets{}
-
-	genericFlagSet := fss.FlagSet("generic")
-	opts.AddFlags(genericFlagSet)
-
-	// Set klog flags
-	logsFlagSet := fss.FlagSet("logs")
-	klogflag.Add(logsFlagSet)
-
 	cmd.AddCommand(sharedcommand.NewCmdVersion(names.KarmadaDeschedulerComponentName))
 	cmd.Flags().AddFlagSet(genericFlagSet)
 	cmd.Flags().AddFlagSet(logsFlagSet)

cmd/descheduler/main.go

@@ -20,6 +20,7 @@ import (
 	"os"
 
 	"k8s.io/component-base/cli"
+	"k8s.io/component-base/logs"
 	_ "k8s.io/component-base/logs/json/register" // for JSON log format registration
 	controllerruntime "sigs.k8s.io/controller-runtime"
 
@@ -28,7 +29,8 @@ import (
 
 func main() {
 	ctx := controllerruntime.SetupSignalHandler()
-	command := app.NewDeschedulerCommand(ctx)
-	code := cli.Run(command)
-	os.Exit(code)
+	cmd := app.NewDeschedulerCommand(ctx)
+	exitCode := cli.Run(cmd)
+	logs.FlushLogs()
+	os.Exit(exitCode)
 }