feat: use klog as the default logging library (#1008)

Makefile

@@ -213,9 +213,9 @@ scan:
 		./
 
 .PHONY: lint
-lint:
+lint: fmt vet
 	golangci-lint run --new -c .golangci.yaml ${BUILDPATHS}
 
 .PHONY: lint-and-fix
-lint-and-fix:
+lint-and-fix: fmt vet
 	golangci-lint run --new --fix -c .golangci.yaml ${BUILDPATHS}

cmd/analyze/cli/root.go

@@ -4,7 +4,6 @@ import (
 	"os"
 	"strings"
 
-	"github.com/go-logr/logr"
 	"github.com/replicatedhq/troubleshoot/cmd/util"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
 	"github.com/replicatedhq/troubleshoot/pkg/logger"
@@ -24,13 +23,10 @@ func RootCmd() *cobra.Command {
 			v := viper.GetViper()
 			v.BindPFlags(cmd.Flags())
 
-			if !v.GetBool("debug") {
-				klog.SetLogger(logr.Discard())
-			}
-			logger.SetQuiet(v.GetBool("quiet"))
+			logger.SetupLogger(v)
 
 			if err := util.StartProfiling(); err != nil {
-				logger.Printf("Failed to start profiling: %v", err)
+				klog.Errorf("Failed to start profiling: %v", err)
 			}
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
@@ -40,7 +36,7 @@ func RootCmd() *cobra.Command {
 		},
 		PostRun: func(cmd *cobra.Command, args []string) {
 			if err := util.StopProfiling(); err != nil {
-				logger.Printf("Failed to stop profiling: %v", err)
+				klog.Errorf("Failed to stop profiling: %v", err)
 			}
 		},
 	}
@@ -54,6 +50,9 @@ func RootCmd() *cobra.Command {
 
 	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
 
+	// Initialize klog flags
+	logger.InitKlogFlags(cmd)
+
 	k8sutil.AddFlags(cmd.Flags())
 
 	// CPU and memory profiling flags

cmd/collect/cli/root.go

@@ -4,7 +4,6 @@ import (
 	"os"
 	"strings"
 
-	"github.com/go-logr/logr"
 	"github.com/replicatedhq/troubleshoot/cmd/util"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
 	"github.com/replicatedhq/troubleshoot/pkg/logger"
@@ -24,23 +23,20 @@ func RootCmd() *cobra.Command {
 			v := viper.GetViper()
 			v.BindPFlags(cmd.Flags())
 
-			if !v.GetBool("debug") {
-				klog.SetLogger(logr.Discard())
-			}
+			logger.SetupLogger(v)
 
 			if err := util.StartProfiling(); err != nil {
-				logger.Printf("Failed to start profiling: %v", err)
+				klog.Errorf("Failed to start profiling: %v", err)
 			}
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			v := viper.GetViper()
 
-			logger.SetQuiet(v.GetBool("quiet"))
 			return runCollect(v, args[0])
 		},
 		PostRun: func(cmd *cobra.Command, args []string) {
 			if err := util.StopProfiling(); err != nil {
-				logger.Printf("Failed to stop profiling: %v", err)
+				klog.Errorf("Failed to stop profiling: %v", err)
 			}
 		},
 	}
@@ -68,6 +64,9 @@ func RootCmd() *cobra.Command {
 
 	k8sutil.AddFlags(cmd.Flags())
 
+	// Initialize klog flags
+	logger.InitKlogFlags(cmd)
+
 	// CPU and memory profiling flags
 	util.AddProfilingFlags(cmd)
 

cmd/preflight/cli/root.go

@@ -5,7 +5,6 @@ import (
 	"os"
 	"strings"
 
-	"github.com/go-logr/logr"
 	"github.com/replicatedhq/troubleshoot/cmd/util"
 	"github.com/replicatedhq/troubleshoot/internal/traces"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
@@ -29,12 +28,10 @@ that a cluster meets the requirements to run an application.`,
 			v.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
 			v.BindPFlags(cmd.Flags())
 
-			if !v.GetBool("debug") {
-				klog.SetLogger(logr.Discard())
-			}
+			logger.SetupLogger(v)
 
 			if err := util.StartProfiling(); err != nil {
-				logger.Printf("Failed to start profiling: %v", err)
+				klog.Errorf("Failed to start profiling: %v", err)
 			}
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
@@ -42,20 +39,20 @@ that a cluster meets the requirements to run an application.`,
 			closer, err := traces.ConfigureTracing("preflight")
 			if err != nil {
 				// Do not fail running preflights if tracing fails
-				logger.Printf("Failed to initialize open tracing provider: %v", err)
+				klog.Errorf("Failed to initialize open tracing provider: %v", err)
 			} else {
 				defer closer()
 			}
 
 			err = preflight.RunPreflights(v.GetBool("interactive"), v.GetString("output"), v.GetString("format"), args)
-			if v.GetBool("debug") {
+			if v.GetBool("debug") || v.IsSet("v") {
 				fmt.Printf("\n%s", traces.GetExporterInstance().GetSummary())
 			}
 			return err
 		},
 		PostRun: func(cmd *cobra.Command, args []string) {
 			if err := util.StopProfiling(); err != nil {
-				logger.Printf("Failed to stop profiling: %v", err)
+				klog.Errorf("Failed to stop profiling: %v", err)
 			}
 		},
 	}
@@ -67,6 +64,9 @@ that a cluster meets the requirements to run an application.`,
 
 	k8sutil.AddFlags(cmd.Flags())
 
+	// Initialize klog flags
+	logger.InitKlogFlags(cmd)
+
 	// CPU and memory profiling flags
 	util.AddProfilingFlags(cmd)
 

cmd/troubleshoot/cli/analyze.go

@@ -10,7 +10,6 @@ import (
 	"github.com/replicatedhq/troubleshoot/cmd/util"
 	analyzer "github.com/replicatedhq/troubleshoot/pkg/analyze"
 	"github.com/replicatedhq/troubleshoot/pkg/convert"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 	"gopkg.in/yaml.v2"
@@ -28,8 +27,6 @@ func Analyze() *cobra.Command {
 		RunE: func(cmd *cobra.Command, args []string) error {
 			v := viper.GetViper()
 
-			logger.SetQuiet(v.GetBool("quiet"))
-
 			specPath := args[0]
 			analyzerSpec, err := downloadAnalyzerSpec(specPath)
 			if err != nil {

cmd/troubleshoot/cli/redact.go

@@ -8,7 +8,6 @@ import (
 	"github.com/pkg/errors"
 	analyzer "github.com/replicatedhq/troubleshoot/pkg/analyze"
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/supportbundle"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
@@ -35,8 +34,6 @@ For more information on redactors visit https://troubleshoot.sh/docs/redact/
 		RunE: func(cmd *cobra.Command, args []string) error {
 			v := viper.GetViper()
 
-			logger.SetQuiet(v.GetBool("quiet"))
-
 			// 1. Decode redactors from provided URLs
 			redactors, err := supportbundle.GetRedactorsFromURIs(args)
 			if err != nil {

cmd/troubleshoot/cli/root.go

@@ -5,7 +5,6 @@ import (
 	"os"
 	"strings"
 
-	"github.com/go-logr/logr"
 	"github.com/replicatedhq/troubleshoot/cmd/util"
 	"github.com/replicatedhq/troubleshoot/internal/traces"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
@@ -28,30 +27,25 @@ from a server that can be used to assist when troubleshooting a Kubernetes clust
 			v.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
 			v.BindPFlags(cmd.Flags())
 
+			logger.SetupLogger(v)
+
 			if err := util.StartProfiling(); err != nil {
-				logger.Printf("Failed to start profiling: %v", err)
+				klog.Errorf("Failed to start profiling: %v", err)
 			}
 		},
-		PreRun: func(cmd *cobra.Command, args []string) {
-			v := viper.GetViper()
-			if !v.GetBool("debug") {
-				klog.SetLogger(logr.Discard())
-			}
-			logger.SetQuiet(!v.GetBool("debug"))
-		},
 		RunE: func(cmd *cobra.Command, args []string) error {
 			v := viper.GetViper()
 
 			closer, err := traces.ConfigureTracing("support-bundle")
 			if err != nil {
 				// Do not fail running support-bundle if tracing fails
-				logger.Printf("Failed to initialize open tracing provider: %v", err)
+				klog.Errorf("Failed to initialize open tracing provider: %v", err)
 			} else {
 				defer closer()
 			}
 
 			err = runTroubleshoot(v, args)
-			if v.GetBool("debug") {
+			if v.GetBool("debug") || v.IsSet("v") {
 				fmt.Printf("\n%s", traces.GetExporterInstance().GetSummary())
 			}
 
@@ -59,7 +53,7 @@ from a server that can be used to assist when troubleshooting a Kubernetes clust
 		},
 		PersistentPostRun: func(cmd *cobra.Command, args []string) {
 			if err := util.StopProfiling(); err != nil {
-				logger.Printf("Failed to stop profiling: %v", err)
+				klog.Errorf("Failed to stop profiling: %v", err)
 			}
 		},
 	}
@@ -79,7 +73,7 @@ from a server that can be used to assist when troubleshooting a Kubernetes clust
 	cmd.Flags().String("since-time", "", "force pod logs collectors to return logs after a specific date (RFC3339)")
 	cmd.Flags().String("since", "", "force pod logs collectors to return logs newer than a relative duration like 5s, 2m, or 3h.")
 	cmd.Flags().StringP("output", "o", "", "specify the output file path for the support bundle")
-	cmd.Flags().Bool("debug", false, "enable debug logging")
+	cmd.Flags().Bool("debug", false, "enable debug logging. This is equivalent to --v=0")
 
 	// hidden in favor of the `insecure-skip-tls-verify` flag
 	cmd.Flags().Bool("allow-insecure-connections", false, "when set, do not verify TLS certs when retrieving spec and reporting results")
@@ -91,6 +85,9 @@ from a server that can be used to assist when troubleshooting a Kubernetes clust
 
 	k8sutil.AddFlags(cmd.Flags())
 
+	// Initialize klog flags
+	logger.InitKlogFlags(cmd)
+
 	// CPU and memory profiling flags
 	util.AddProfilingFlags(cmd)
 

cmd/troubleshoot/cli/run.go

@@ -23,7 +23,6 @@ import (
 	"github.com/replicatedhq/troubleshoot/pkg/convert"
 	"github.com/replicatedhq/troubleshoot/pkg/httputil"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/specs"
 	"github.com/replicatedhq/troubleshoot/pkg/supportbundle"
 	"github.com/spf13/viper"
@@ -31,6 +30,7 @@ import (
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 func runTroubleshoot(v *viper.Viper, arg []string) error {
@@ -134,13 +134,13 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 		// Search cluster for Troubleshoot objects in cluster
 		bundlesFromSecrets, err := specs.LoadFromSecretMatchingLabel(client, parsedSelector.String(), namespace, specs.SupportBundleKey)
 		if err != nil {
-			logger.Printf("failed to load support bundle spec from secrets: %s", err)
+			klog.Errorf("failed to load support bundle spec from secrets: %s", err)
 		}
 		bundlesFromCluster = append(bundlesFromCluster, bundlesFromSecrets...)
 
 		bundlesFromConfigMaps, err := specs.LoadFromConfigMapMatchingLabel(client, parsedSelector.String(), namespace, specs.SupportBundleKey)
 		if err != nil {
-			logger.Printf("failed to load support bundle spec from secrets: %s", err)
+			klog.Errorf("failed to load support bundle spec from secrets: %s", err)
 		}
 		bundlesFromCluster = append(bundlesFromCluster, bundlesFromConfigMaps...)
 
@@ -148,7 +148,7 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 			multidocs := strings.Split(string(bundle), "\n---\n")
 			parsedBundleFromSecret, err := supportbundle.ParseSupportBundleFromDoc([]byte(multidocs[0]))
 			if err != nil {
-				logger.Printf("failed to parse support bundle spec:  %s", err)
+				klog.Errorf("failed to parse support bundle spec:  %s", err)
 				continue
 			}
 
@@ -160,7 +160,7 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 
 			parsedRedactors, err := supportbundle.ParseRedactorsFromDocs(multidocs)
 			if err != nil {
-				logger.Printf("failed to parse redactors from doc:  %s", err)
+				klog.Errorf("failed to parse redactors from doc:  %s", err)
 				continue
 			}
 
@@ -172,13 +172,13 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 		// Search cluster for Troubleshoot objects in ConfigMaps
 		redactorsFromSecrets, err := specs.LoadFromSecretMatchingLabel(client, parsedSelector.String(), namespace, specs.RedactorKey)
 		if err != nil {
-			logger.Printf("failed to load redactor specs from config maps: %s", err)
+			klog.Errorf("failed to load redactor specs from config maps: %s", err)
 		}
 		redactorsFromCluster = append(redactorsFromCluster, redactorsFromSecrets...)
 
 		redactorsFromConfigMaps, err := specs.LoadFromConfigMapMatchingLabel(client, parsedSelector.String(), namespace, specs.RedactorKey)
 		if err != nil {
-			logger.Printf("failed to load redactor specs from config maps: %s", err)
+			klog.Errorf("failed to load redactor specs from config maps: %s", err)
 		}
 		redactorsFromCluster = append(redactorsFromCluster, redactorsFromConfigMaps...)
 
@@ -186,7 +186,7 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 			multidocs := strings.Split(string(redactor), "\n---\n")
 			parsedRedactors, err := supportbundle.ParseRedactorsFromDocs(multidocs)
 			if err != nil {
-				logger.Printf("failed to parse redactors from doc:  %s", err)
+				klog.Errorf("failed to parse redactors from doc:  %s", err)
 			}
 
 			additionalRedactors.Spec.Redactors = append(additionalRedactors.Spec.Redactors, parsedRedactors...)
@@ -229,7 +229,7 @@ func runTroubleshoot(v *viper.Viper, arg []string) error {
 		go func() {
 			defer wg.Done()
 			for msg := range progressChan {
-				logger.Printf("Collecting support bundle: %v", msg)
+				klog.Infof("Collecting support bundle: %v", msg)
 			}
 		}()
 	} else {

cmd/util/util.go

@@ -4,6 +4,9 @@ import (
 	"net/url"
 	"os"
 	"strings"
+
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 func HomeDir() string {
@@ -23,7 +26,7 @@ func IsURL(str string) bool {
 }
 
 func AppName(name string) string {
-	words := strings.Split(strings.Title(strings.Replace(name, "-", " ", -1)), " ")
+	words := strings.Split(cases.Title(language.English).String(strings.ReplaceAll(name, "-", " ")), " ")
 	casedWords := []string{}
 	for i, word := range words {
 		if strings.ToLower(word) == "ai" {

internal/traces/otel.go

@@ -3,13 +3,13 @@ package traces
 import (
 	"context"
 
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/version"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/sdk/resource"
 	"go.opentelemetry.io/otel/sdk/trace"
 	semconv "go.opentelemetry.io/otel/semconv/v1.12.0"
+	"k8s.io/klog/v2"
 )
 
 // ConfigureTracing configures the OpenTelemetry trace provider for CLI
@@ -54,7 +54,7 @@ func ConfigureTracing(processName string) (func(), error) {
 
 	return func() {
 		if err := tp.Shutdown(context.Background()); err != nil {
-			logger.Printf("Failed to shutdown trace provider: %v", err)
+			klog.Errorf("Failed to shutdown trace provider: %v", err)
 		}
 	}, nil
 }

pkg/analyze/analyzer.go

@@ -9,12 +9,12 @@ import (
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/multitype"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	corev1 "k8s.io/api/core/v1"
+	"k8s.io/klog/v2"
 )
 
 type AnalyzeResult struct {
@@ -73,7 +73,7 @@ func HostAnalyze(
 
 	isExcluded, _ := analyzer.IsExcluded()
 	if isExcluded {
-		logger.Printf("Excluding %q analyzer", analyzer.Title())
+		klog.Infof("excluding %q analyzer", analyzer.Title())
 		span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 		return nil
 	}
@@ -129,7 +129,7 @@ func Analyze(
 		return nil, err
 	}
 	if isExcluded {
-		logger.Printf("Excluding %q analyzer", analyzerInst.Title())
+		klog.Infof("excluding %q analyzer", analyzerInst.Title())
 		span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 		return nil, nil
 	}

pkg/analyze/download.go

@@ -15,9 +15,9 @@ import (
 	troubleshootscheme "github.com/replicatedhq/troubleshoot/pkg/client/troubleshootclientset/scheme"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	"github.com/replicatedhq/troubleshoot/pkg/docrewrite"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/types"
 	"k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/klog/v2"
 )
 
 type fileContentProvider struct {
@@ -42,7 +42,7 @@ func AnalyzeLocal(
 	for _, analyzer := range analyzers {
 		analyzeResult, err := Analyze(ctx, analyzer, fcp.getFileContents, fcp.getChildFileContents)
 		if err != nil {
-			logger.Printf("An analyzer failed to run: %v", err)
+			klog.Errorf("An analyzer failed to run: %v", err)
 			continue
 		}
 

pkg/collect/ceph.go

@@ -9,10 +9,10 @@ import (
 
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 const (
@@ -213,7 +213,7 @@ func findRookCephToolsPod(ctx context.Context, c *CollectCeph, namespace string)
 		return &pods[0], nil
 	}
 
-	logger.Printf("rook ceph tools pod not found")
+	klog.Info("rook ceph tools pod not found")
 
 	return nil, nil
 }

pkg/collect/collect.go

@@ -71,6 +71,7 @@ func CollectHost(c *troubleshootv1beta2.HostCollector, additionalRedactors *trou
 	for _, collector := range collectors {
 		isExcluded, _ := collector.IsExcluded()
 		if isExcluded {
+			opts.ProgressChan <- fmt.Sprintf("[%s] Excluding collector", collector.Title())
 			continue
 		}
 

pkg/collect/copy_from_host.go

@@ -12,7 +12,6 @@ import (
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/segmentio/ksuid"
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
@@ -24,6 +23,7 @@ import (
 	"k8s.io/client-go/rest"
 	restclient "k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/remotecommand"
+	"k8s.io/klog/v2"
 )
 
 type CollectCopyFromHost struct {
@@ -204,7 +204,7 @@ func copyFromHostCreateDaemonSet(ctx context.Context, client kubernetes.Interfac
 		cleanupFuncs = append(cleanupFuncs, func() {
 			err := client.CoreV1().Secrets(namespace).Delete(context.Background(), collector.ImagePullSecret.Name, metav1.DeleteOptions{})
 			if err != nil && !kuberneteserrors.IsNotFound(err) {
-				logger.Printf("Failed to delete secret %s: %v", collector.ImagePullSecret.Name, err)
+				klog.Errorf("Failed to delete secret %s: %v", collector.ImagePullSecret.Name, err)
 			}
 		})
 	}
@@ -215,7 +215,7 @@ func copyFromHostCreateDaemonSet(ctx context.Context, client kubernetes.Interfac
 	}
 	cleanupFuncs = append(cleanupFuncs, func() {
 		if err := client.AppsV1().DaemonSets(namespace).Delete(context.Background(), createdDS.Name, metav1.DeleteOptions{}); err != nil {
-			logger.Printf("Failed to delete daemonset %s: %v", createdDS.Name, err)
+			klog.Errorf("Failed to delete daemonset %s: %v", createdDS.Name, err)
 		}
 	})
 

pkg/collect/logs.go

@@ -11,11 +11,11 @@ import (
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 type CollectLogs struct {
@@ -243,7 +243,7 @@ func savePodLogs(
 func convertMaxAgeToTime(maxAge string) *metav1.Time {
 	parsedDuration, err := time.ParseDuration(maxAge)
 	if err != nil {
-		logger.Printf("Failed to parse time duration %s", maxAge)
+		klog.Errorf("Failed to parse time duration %s", maxAge)
 		return nil
 	}
 

pkg/collect/longhorn.go

@@ -12,7 +12,6 @@ import (
 
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	longhornv1beta1types "github.com/replicatedhq/troubleshoot/pkg/longhorn/apis/longhorn/v1beta1"
 	longhornv1beta1 "github.com/replicatedhq/troubleshoot/pkg/longhorn/client/clientset/versioned/typed/longhorn/v1beta1"
 	longhorntypes "github.com/replicatedhq/troubleshoot/pkg/longhorn/types"
@@ -22,6 +21,7 @@ import (
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/remotecommand"
+	"k8s.io/klog/v2"
 )
 
 const (
@@ -69,8 +69,8 @@ func (c *CollectLonghorn) Collect(progressChan chan<- interface{}) (CollectorRes
 	if err != nil {
 		if apiErr, ok := err.(*apiErrors.StatusError); ok {
 			if apiErr.ErrStatus.Code == http.StatusNotFound {
-				logger.Printf("list nodes.longhorn.io not found")
-				return nil, nil
+				klog.Error("list nodes.longhorn.io not found")
+				return NewResult(), nil
 			}
 		}
 		return nil, errors.Wrap(err, "list nodes.longhorn.io")
@@ -280,7 +280,7 @@ func (c *CollectLonghorn) Collect(progressChan chan<- interface{}) (CollectorRes
 				defer wg.Done()
 				checksums, err := GetLonghornReplicaChecksum(c.ClientConfig, replica, podName)
 				if err != nil {
-					logger.Printf("Failed to get replica %s checksum: %v", replica.Name, err)
+					klog.Errorf("Failed to get replica %s checksum: %v", replica.Name, err)
 					return
 				}
 				volsDir := GetLonghornVolumesDirectory(ns)

pkg/collect/redact.go

@@ -49,9 +49,9 @@ func RedactResult(bundlePath string, input CollectorResult, additionalRedactors
 				if err != nil {
 					return errors.Wrap(err, "failed to get relative path")
 				}
-				klog.V(4).Infof("Redacting %s (symlink => %s)\n", file, symlink)
+				klog.V(2).Infof("Redacting %s (symlink => %s)\n", file, symlink)
 			} else {
-				klog.V(4).Infof("Redacting %s\n", file)
+				klog.V(2).Infof("Redacting %s\n", file)
 			}
 			r, err := input.GetReader(bundlePath, file)
 			if err != nil {

pkg/collect/run_pod.go

@@ -12,11 +12,11 @@ import (
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/client-go/kubernetes"
 	v1 "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 
 	kuberneteserrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -54,7 +54,7 @@ func (c *CollectRunPod) Collect(progressChan chan<- interface{}) (CollectorResul
 	}
 	defer func() {
 		if err := client.CoreV1().Pods(pod.Namespace).Delete(context.Background(), pod.Name, metav1.DeleteOptions{}); err != nil {
-			logger.Printf("Failed to delete pod %s: %v", pod.Name, err)
+			klog.Errorf("Failed to delete pod %s: %v", pod.Name, err)
 		}
 	}()
 
@@ -62,7 +62,7 @@ func (c *CollectRunPod) Collect(progressChan chan<- interface{}) (CollectorResul
 		defer func() {
 			for _, k := range pod.Spec.ImagePullSecrets {
 				if err := client.CoreV1().Secrets(pod.Namespace).Delete(context.Background(), k.Name, metav1.DeleteOptions{}); err != nil {
-					logger.Printf("Failed to delete secret %s: %v", k.Name, err)
+					klog.Errorf("Failed to delete secret %s: %v", k.Name, err)
 				}
 			}
 		}()
@@ -316,7 +316,7 @@ func RunPodsReadyNodes(ctx context.Context, client v1.CoreV1Interface, opts RunP
 			}
 			logs, err := RunPodLogs(ctx, client, pod)
 			if err != nil {
-				logger.Printf("Failed to run pod on node %s: %v", node, err)
+				klog.Errorf("Failed to run pod on node %s: %v", node, err)
 				return
 			}
 
@@ -341,7 +341,7 @@ func RunPodLogs(ctx context.Context, client v1.CoreV1Interface, podSpec *corev1.
 	defer func() {
 		err := client.Pods(pod.Namespace).Delete(context.Background(), pod.Name, metav1.DeleteOptions{})
 		if err != nil && !kuberneteserrors.IsNotFound(err) {
-			logger.Printf("Failed to delete pod %s: %v\n", pod.Name, err)
+			klog.Errorf("Failed to delete pod %s: %v\n", pod.Name, err)
 		}
 	}()
 

pkg/collect/runner.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	corev1 "k8s.io/api/core/v1"
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
 	kuberneteserrors "k8s.io/apimachinery/pkg/api/errors"
@@ -18,6 +17,7 @@ import (
 	runtime "k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/util/retry"
+	"k8s.io/klog/v2"
 	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
 )
 
@@ -43,10 +43,10 @@ func (r *podRunner) run(ctx context.Context, collector *troubleshootv1beta2.Host
 
 	defer func() {
 		if err := r.client.CoreV1().Pods(namespace).Delete(context.Background(), pod.Name, metav1.DeleteOptions{}); err != nil {
-			logger.Printf("Failed to delete pod %s: %v\n", pod.Name, err)
+			klog.Errorf("Failed to delete pod %s: %v\n", pod.Name, err)
 		}
 		if err := r.client.CoreV1().ConfigMaps(namespace).Delete(context.Background(), cm.Name, metav1.DeleteOptions{}); err != nil {
-			logger.Printf("Failed to delete configmap %s: %v\n", pod.Name, err)
+			klog.Errorf("Failed to delete configmap %s: %v\n", pod.Name, err)
 		}
 	}()
 

pkg/collect/sysctl.go

@@ -9,11 +9,11 @@ import (
 	"github.com/pkg/errors"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/k8sutil"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	kuberneteserrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 type CollectSysctl struct {
@@ -82,7 +82,7 @@ find /proc/sys/vm -type f | while read f; do v=$(cat $f 2>/dev/null); echo "$f =
 			defer func() {
 				err := c.Client.CoreV1().Secrets(c.Collector.Namespace).Delete(context.Background(), c.Collector.ImagePullSecret.Name, metav1.DeleteOptions{})
 				if err != nil && !kuberneteserrors.IsNotFound(err) {
-					logger.Printf("Failed to delete secret %s: %v", c.Collector.ImagePullSecret.Name, err)
+					klog.Errorf("Failed to delete secret %s: %v", c.Collector.ImagePullSecret.Name, err)
 				}
 			}()
 

pkg/logger/logger.go

@@ -1,26 +1,65 @@
+/*
+Logging library for the troubleshoot framework.
+
+Logging levels
+TODO: Document me here => https://github.com/replicatedhq/troubleshoot/issues/1031
+
+0: also the same as not using V() log progress related information within the framework. Logs within each component (collector/analyzers/etc) should not use this level.
+
+1: High level logs within each component (collector/analyzers/etc) should use this level. A log such as "Ceph collector connected to the cluster" belongs here.
+
+2: Everything else goes here. If you do not know which level to use, use this level.
+
+The best approach is to always use V(2) then after testing your code as a whole, you can elevate the log level of the messages you find useful to V(1) or V(0).
+
+Do not log errors in functions that return an error. Instead, return the error and let the caller log it.
+*/
 package logger
 
 import (
-	"log"
-	"os"
+	"flag"
+	"sync"
+
+	"github.com/go-logr/logr"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	"k8s.io/klog/v2"
 )
 
-var (
-	logger *log.Logger
-	quiet  = false
-)
+var lock sync.Mutex
 
-func init() {
-	logger = log.New(os.Stderr, "", log.LstdFlags)
+// InitKlogFlags initializes klog flags and adds them to the cobra command.
+func InitKlogFlags(cmd *cobra.Command) {
+	// Initialize klog flags
+	klogFlags := flag.NewFlagSet("klog", flag.ExitOnError)
+	klog.InitFlags(klogFlags)
+
+	klogFlags.VisitAll(func(f *flag.Flag) {
+		// Just the flags we want to expose in our CLI
+		if f.Name == "v" {
+			// If we ever want to expose the klog flags that have underscores ("_") in them
+			// we need to replace them with hyphens ("-") in the flag name using
+			// pflag.NormalizedName(strings.ReplaceAll(name, "_", "-")). Check how kubectl does it
+			cmd.Flags().AddGoFlag(f)
+		}
+	})
 }
 
-func SetQuiet(s bool) {
-	quiet = s
+// SetupLogger sets up klog logger based on viper configuration.
+func SetupLogger(v *viper.Viper) {
+	quiet := v.GetBool("debug") || v.IsSet("v")
+	SetQuiet(!quiet)
 }
 
-func Printf(format string, args ...interface{}) {
+// SetQuiet enables or disables klog logger.
+func SetQuiet(quiet bool) {
+	lock.Lock()
+	defer lock.Unlock()
+
 	if quiet {
-		return
+		klog.SetLogger(logr.Discard())
+	} else {
+		// Restore the default logger
+		klog.ClearLogger()
 	}
-	logger.Printf(format, args...)
 }

pkg/preflight/analyze.go

@@ -9,7 +9,7 @@ import (
 
 	analyze "github.com/replicatedhq/troubleshoot/pkg/analyze"
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
+	"k8s.io/klog/v2"
 )
 
 // Analyze runs the analyze phase of preflight checks
@@ -100,7 +100,7 @@ func doAnalyze(
 		if err != nil {
 			strict, strictErr := HasStrictAnalyzer(analyzer)
 			if strictErr != nil {
-				logger.Printf("failed to determine if analyzer %v is strict: %s", analyzer, strictErr)
+				klog.Errorf("failed to determine if analyzer %v is strict: %s", analyzer, strictErr)
 			}
 
 			analyzeResult = []*analyze.AnalyzeResult{

pkg/preflight/collect.go

@@ -12,13 +12,13 @@ import (
 	troubleshootv1beta2 "github.com/replicatedhq/troubleshoot/pkg/apis/troubleshoot/v1beta2"
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/version"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
 )
 
 type CollectOpts struct {
@@ -123,7 +123,7 @@ func CollectHostWithContext(
 
 		isExcluded, _ := collector.IsExcluded()
 		if isExcluded {
-			logger.Printf("Excluding %q collector", collector.Title())
+			opts.ProgressChan <- fmt.Sprintf("[%s] Excluding collector", collector.Title())
 			span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 			span.End()
 			continue
@@ -236,7 +236,7 @@ func CollectWithContext(ctx context.Context, opts CollectOpts, p *troubleshootv1
 
 		isExcluded, _ := collector.IsExcluded()
 		if isExcluded {
-			logger.Printf("Excluding %q collector", collector.Title())
+			klog.Infof("excluding %q collector", collector.Title())
 			span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 			span.End()
 			continue

pkg/redact/yaml.go

@@ -9,8 +9,8 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"gopkg.in/yaml.v2"
+	"k8s.io/klog/v2"
 )
 
 type YamlRedactor struct {
@@ -30,7 +30,7 @@ func (r *YamlRedactor) Redact(input io.Reader, path string) io.Reader {
 	if r.filePath != "" {
 		match, err := filepath.Match(r.filePath, path)
 		if err != nil {
-			logger.Printf("Failed to match %q and %q: %v", r.filePath, path, err)
+			klog.Errorf("Failed to match %q and %q: %v", r.filePath, path, err)
 			return input
 		}
 		if !match {

pkg/supportbundle/collect.go

@@ -15,7 +15,6 @@ import (
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	"github.com/replicatedhq/troubleshoot/pkg/convert"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/version"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
@@ -45,7 +44,7 @@ func runHostCollectors(ctx context.Context, hostCollectors []*troubleshootv1beta
 
 		isExcluded, _ := collector.IsExcluded()
 		if isExcluded {
-			logger.Printf("Excluding %q collector", collector.Title())
+			opts.ProgressChan <- fmt.Sprintf("[%s] Excluding host collector", collector.Title())
 			span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 			span.End()
 			continue
@@ -152,7 +151,8 @@ func runCollectors(ctx context.Context, collectors []*troubleshootv1beta2.Collec
 
 		isExcluded, _ := collector.IsExcluded()
 		if isExcluded {
-			logger.Printf("Excluding %q collector", collector.Title())
+			msg := fmt.Sprintf("excluding %q collector", collector.Title())
+			opts.CollectorProgressCallback(opts.ProgressChan, msg)
 			span.SetAttributes(attribute.Bool(constants.EXCLUDED, true))
 			span.End()
 			continue
@@ -161,7 +161,7 @@ func runCollectors(ctx context.Context, collectors []*troubleshootv1beta2.Collec
 		// skip collectors with RBAC errors unless its the ClusterResources collector
 		if collector.HasRBACErrors() {
 			if _, ok := collector.(*collect.CollectClusterResources); !ok {
-				msg := fmt.Sprintf("skipping collector %s with insufficient RBAC permissions", collector.Title())
+				msg := fmt.Sprintf("skipping collector %q with insufficient RBAC permissions", collector.Title())
 				opts.CollectorProgressCallback(opts.ProgressChan, msg)
 				span.SetStatus(codes.Error, "skipping collector, insufficient RBAC permissions")
 				span.End()

pkg/supportbundle/load.go

@@ -15,10 +15,10 @@ import (
 	troubleshootclientsetscheme "github.com/replicatedhq/troubleshoot/pkg/client/troubleshootclientset/scheme"
 	"github.com/replicatedhq/troubleshoot/pkg/docrewrite"
 	"github.com/replicatedhq/troubleshoot/pkg/httputil"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"github.com/replicatedhq/troubleshoot/pkg/oci"
 	"github.com/replicatedhq/troubleshoot/pkg/specs"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/klog/v2"
 )
 
 func GetSupportBundleFromURI(bundleURI string) (*troubleshootv1beta2.SupportBundle, error) {
@@ -78,10 +78,10 @@ func ParseSupportBundle(doc []byte, followURI bool) (*troubleshootv1beta2.Suppor
 		// use the upstream spec, otherwise fall back to
 		// what's defined in the current spec
 		if supportBundle.Spec.Uri != "" && followURI {
-			logger.Printf("using upstream reference: %+v\n", supportBundle.Spec.Uri)
+			klog.Infof("using upstream reference: %+v\n", supportBundle.Spec.Uri)
 			upstreamSupportBundleContent, err := LoadSupportBundleSpec(supportBundle.Spec.Uri)
 			if err != nil {
-				logger.Printf("failed to load upstream supportbundle, falling back")
+				klog.Errorf("failed to load upstream supportbundle, falling back")
 				return supportBundle, nil
 			}
 
@@ -89,7 +89,7 @@ func ParseSupportBundle(doc []byte, followURI bool) (*troubleshootv1beta2.Suppor
 
 			upstreamSupportBundle, err := ParseSupportBundle([]byte(multidocs[0]), false)
 			if err != nil {
-				logger.Printf("failed to parse upstream supportbundle, falling back")
+				klog.Errorf("failed to parse upstream supportbundle, falling back")
 				return supportBundle, nil
 			}
 			return upstreamSupportBundle, nil

pkg/supportbundle/supportbundle.go

@@ -19,7 +19,6 @@ import (
 	"github.com/replicatedhq/troubleshoot/pkg/collect"
 	"github.com/replicatedhq/troubleshoot/pkg/constants"
 	"github.com/replicatedhq/troubleshoot/pkg/convert"
-	"github.com/replicatedhq/troubleshoot/pkg/logger"
 	"go.opentelemetry.io/otel"
 	"k8s.io/client-go/rest"
 	"k8s.io/klog/v2"
@@ -181,7 +180,7 @@ func CollectSupportBundleFromSpec(
 	err = result.SaveResult(bundlePath, "execution-data/summary.txt", bytes.NewReader([]byte(summary)))
 	if err != nil {
 		// Don't fail the support bundle if we can't save the execution summary
-		logger.Printf("failed to save execution summary file in the support bundle: %v", err)
+		klog.Errorf("failed to save execution summary file in the support bundle: %v", err)
 	}
 
 	// Archive Support Bundle