implement "--log_file" and "--log_dir" for klog

cmd/minikube/cmd/root.go

@@ -17,7 +17,7 @@ limitations under the License.
 package cmd
 
 import (
-	goflag "flag"
+	"flag"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -156,6 +156,18 @@ func usageTemplate() string {
 }
 
 func init() {
+	klog.InitFlags(nil)
+	// preset logtostderr and alsologtostderr only for test runs, for normal runs consider flags in main()
+	if strings.HasPrefix(filepath.Base(os.Args[0]), "e2e-") || strings.HasSuffix(os.Args[0], "test") {
+		if err := flag.Set("logtostderr", "false"); err != nil {
+			klog.Warningf("Unable to set default flag value for logtostderr: %v", err)
+		}
+		if err := flag.Set("alsologtostderr", "false"); err != nil {
+			klog.Warningf("Unable to set default flag value for alsologtostderr: %v", err)
+		}
+	}
+	pflag.CommandLine.AddGoFlagSet(flag.CommandLine) // avoid `generate-docs_test.go` complaining about "Docs are not updated"
+
 	RootCmd.PersistentFlags().StringP(config.ProfileName, "p", constants.DefaultClusterName, `The name of the minikube VM being used. This can be set to allow having multiple instances of minikube independently.`)
 	RootCmd.PersistentFlags().StringP(configCmd.Bootstrapper, "b", "kubeadm", "The name of the cluster bootstrapper that will set up the Kubernetes cluster.")
 
@@ -223,15 +235,6 @@ func init() {
 	RootCmd.AddCommand(completionCmd)
 	templates.ActsAsRootCommand(RootCmd, []string{"options"}, groups...)
 
-	klog.InitFlags(nil)
-	if err := goflag.Set("logtostderr", "false"); err != nil {
-		klog.Warningf("Unable to set default flag value for logtostderr: %v", err)
-	}
-	if err := goflag.Set("alsologtostderr", "false"); err != nil {
-		klog.Warningf("Unable to set default flag value for alsologtostderr: %v", err)
-	}
-
-	pflag.CommandLine.AddGoFlagSet(goflag.CommandLine)
 	if err := viper.BindPFlags(RootCmd.PersistentFlags()); err != nil {
 		exit.Error(reason.InternalBindFlags, "Unable to bind flags", err)
 	}

cmd/minikube/main.go

@@ -18,17 +18,15 @@ package main
 
 import (
 	"bytes"
+	"flag"
 	"fmt"
 	"log"
 	"os"
 	"regexp"
 	"strconv"
 
-	// initflag must be imported before any other minikube pkg.
-	// Fix for https://github.com/kubernetes/minikube/issues/4866
-
+	"github.com/spf13/pflag"
 	"k8s.io/klog/v2"
-	_ "k8s.io/minikube/pkg/initflag"
 
 	// Register drivers
 	_ "k8s.io/minikube/pkg/minikube/registry/drvs"
@@ -61,6 +59,8 @@ func main() {
 	bridgeLogMessages()
 	defer klog.Flush()
 
+	setFlags()
+
 	s := stacklog.MustStartFromEnv("STACKLOG_PATH")
 	defer s.Stop()
 
@@ -120,3 +120,33 @@ func (lb machineLogBridge) Write(b []byte) (n int, err error) {
 	}
 	return len(b), nil
 }
+
+// setFlags sets the flags
+func setFlags() {
+	// parse flags beyond subcommand - get aroung go flag 'limitations':
+	// "Flag parsing stops just before the first non-flag argument" (ref: https://pkg.go.dev/flag#hdr-Command_line_flag_syntax)
+	pflag.CommandLine.ParseErrorsWhitelist.UnknownFlags = true
+	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
+	pflag.Parse()
+
+	// set default flag value for logtostderr and alsologtostderr but don't override user's preferences
+	if !pflag.CommandLine.Changed("logtostderr") {
+		if err := pflag.Set("logtostderr", "false"); err != nil {
+			klog.Warningf("Unable to set default flag value for logtostderr: %v", err)
+		}
+	}
+	if !pflag.CommandLine.Changed("alsologtostderr") {
+		if err := pflag.Set("alsologtostderr", "false"); err != nil {
+			klog.Warningf("Unable to set default flag value for alsologtostderr: %v", err)
+		}
+	}
+
+	// make sure log_dir exists if log_file is not also set - the log_dir is mutually exclusive with the log_file option
+	// ref: https://github.com/kubernetes/klog/blob/52c62e3b70a9a46101f33ebaf0b100ec55099975/klog.go#L491
+	if pflag.Lookup("log_file") != nil && pflag.Lookup("log_file").Value.String() == "" &&
+		pflag.Lookup("log_dir") != nil && pflag.Lookup("log_dir").Value.String() != "" {
+		if err := os.MkdirAll(pflag.Lookup("log_dir").Value.String(), 0755); err != nil {
+			klog.Warningf("unable to create log directory: %v", err)
+		}
+	}
+}

pkg/minikube/extract/extract.go

@@ -29,10 +29,6 @@ import (
 	"strconv"
 	"strings"
 
-	// initflag must be imported before any other minikube pkg.
-	// Fix for https://github.com/kubernetes/minikube/issues/4866
-	_ "k8s.io/minikube/pkg/initflag"
-
 	"github.com/golang-collections/collections/stack"
 	"github.com/pkg/errors"
 	"k8s.io/minikube/pkg/util/lock"

pkg/minikube/translate/translate.go

@@ -104,7 +104,8 @@ func DetermineLocale() {
 
 // setPreferredLanguageTag configures which language future messages should use.
 func setPreferredLanguageTag(l language.Tag) {
-	klog.Infof("Setting Language to %s ...", l)
+	// output message only if verbosity level is set and we still haven't got all the flags parsed in main()
+	klog.V(1).Infof("Setting Language to %s ...", l)
 	preferredLanguage = l
 }