fix: honor klog -stderrthreshold when -logtostderr is enabled

klog v2 defaults -logtostderr to true. When this flag is active, the
-stderrthreshold flag is silently ignored — all log messages are
unconditionally written to stderr regardless of severity.

Bump klog from v2.130.1 to v2.140.0 in both staging modules (cli,
code-generator) and opt into the fixed behavior in all 6 binaries
(kubectl-kcp, kubectl-ws, kubectl-create-workspace, cluster-client-gen,
cluster-informer-gen, cluster-lister-gen).

The default stderrthreshold remains INFO so the observable behavior is
unchanged.

Ref: kubernetes/klog#212, kubernetes/klog#432
Signed-off-by: Pierluigi Lenoci <pierluigilenoci@gmail.com>

Author: pierluigilenoci

staging/src/github.com/kcp-dev/cli/cmd/kubectl-create-workspace/cmd/kubectlCreateWorkspace.go

@@ -39,6 +39,11 @@ func KubectlCreateWorkspaceCommand() *cobra.Command {
 	// setup klog
 	fs := goflags.NewFlagSet("klog", goflags.PanicOnError)
 	klog.InitFlags(fs)
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = fs.Set("legacy_stderr_threshold_behavior", "false")
+	_ = fs.Set("stderrthreshold", "INFO")
 	createWorkspaceCommand.PersistentFlags().AddGoFlagSet(fs)
 	return createWorkspaceCommand
 }

staging/src/github.com/kcp-dev/cli/cmd/kubectl-kcp/cmd/kubectlKcp.go

@@ -56,6 +56,11 @@ func KubectlKcpCommand() *cobra.Command {
 	// setup klog
 	fs := goflags.NewFlagSet("klog", goflags.PanicOnError)
 	klog.InitFlags(fs)
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = fs.Set("legacy_stderr_threshold_behavior", "false")
+	_ = fs.Set("stderrthreshold", "INFO")
 	root.PersistentFlags().AddGoFlagSet(fs)
 
 	if v := version.Get().String(); len(v) == 0 {

staging/src/github.com/kcp-dev/cli/cmd/kubectl-ws/cmd/kubectlWs.go

@@ -39,6 +39,11 @@ func KubectlWsCommand() *cobra.Command {
 	// setup klog
 	fs := goflags.NewFlagSet("klog", goflags.PanicOnError)
 	klog.InitFlags(fs)
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = fs.Set("legacy_stderr_threshold_behavior", "false")
+	_ = fs.Set("stderrthreshold", "INFO")
 	wsCommand.PersistentFlags().AddGoFlagSet(fs)
 	return wsCommand
 }

staging/src/github.com/kcp-dev/cli/go.mod

@@ -18,7 +18,7 @@ require (
 	k8s.io/cli-runtime v0.33.3
 	k8s.io/client-go v0.35.1
 	k8s.io/component-base v0.35.1
-	k8s.io/klog/v2 v2.130.1
+	k8s.io/klog/v2 v2.140.0
 )
 
 replace (

staging/src/github.com/kcp-dev/cli/go.sum

@@ -226,8 +226,8 @@ k8s.io/client-go v0.35.1 h1:+eSfZHwuo/I19PaSxqumjqZ9l5XiTEKbIaJ+j1wLcLM=
 k8s.io/client-go v0.35.1/go.mod h1:1p1KxDt3a0ruRfc/pG4qT/3oHmUj1AhSHEcxNSGg+OA=
 k8s.io/component-base v0.35.1 h1:XgvpRf4srp037QWfGBLFsYMUQJkE5yMa94UsJU7pmcE=
 k8s.io/component-base v0.35.1/go.mod h1:HI/6jXlwkiOL5zL9bqA3en1Ygv60F03oEpnuU1G56Bs=
-k8s.io/klog/v2 v2.130.1 h1:n9Xl7H1Xvksem4KFG4PYbdQCQxqc/tTUyrgXaOhHSzk=
-k8s.io/klog/v2 v2.130.1/go.mod h1:3Jpz1GvMt720eyJH1ckRHK1EDfpxISzJ7I9OYgaDtPE=
+k8s.io/klog/v2 v2.140.0 h1:Tf+J3AH7xnUzZyVVXhTgGhEKnFqye14aadWv7bzXdzc=
+k8s.io/klog/v2 v2.140.0/go.mod h1:o+/RWfJ6PwpnFn7OyAG3QnO47BFsymfEfrz6XyYSSp0=
 k8s.io/kube-openapi v0.0.0-20250910181357-589584f1c912 h1:Y3gxNAuB0OBLImH611+UDZcmKS3g6CthxToOb37KgwE=
 k8s.io/kube-openapi v0.0.0-20250910181357-589584f1c912/go.mod h1:kdmbQkyfwUagLfXIad1y2TdrjPFWp2Q89B3qkRwf/pQ=
 k8s.io/utils v0.0.0-20251002143259-bc988d571ff4 h1:SjGebBtkBqHFOli+05xYbK8YF1Dzkbzn+gDM4X9T4Ck=

staging/src/github.com/kcp-dev/code-generator/cmd/cluster-client-gen/main.go

@@ -39,6 +39,11 @@ func main() {
 
 	args.AddFlags(pflag.CommandLine, "k8s.io/kubernetes/pkg/apis") // TODO: move this input path out of client-gen
 	_ = flag.Set("logtostderr", "true")
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = flag.Set("legacy_stderr_threshold_behavior", "false")
+	_ = flag.Set("stderrthreshold", "INFO")
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
 	pflag.Parse()
 

staging/src/github.com/kcp-dev/code-generator/cmd/cluster-informer-gen/main.go

@@ -37,6 +37,11 @@ func main() {
 
 	args.AddFlags(pflag.CommandLine)
 	_ = flag.Set("logtostderr", "true")
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = flag.Set("legacy_stderr_threshold_behavior", "false")
+	_ = flag.Set("stderrthreshold", "INFO")
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
 	pflag.Parse()
 

staging/src/github.com/kcp-dev/code-generator/cmd/cluster-lister-gen/main.go

@@ -37,6 +37,11 @@ func main() {
 
 	args.AddFlags(pflag.CommandLine)
 	_ = flag.Set("logtostderr", "true")
+	// Opt into the new klog behavior so that -stderrthreshold is honored even
+	// when -logtostderr=true (the default).
+	// Ref: kubernetes/klog#212, kubernetes/klog#432
+	_ = flag.Set("legacy_stderr_threshold_behavior", "false")
+	_ = flag.Set("stderrthreshold", "INFO")
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
 	pflag.Parse()
 

staging/src/github.com/kcp-dev/code-generator/go.mod

@@ -7,7 +7,7 @@ require (
 	golang.org/x/text v0.31.0
 	k8s.io/code-generator v0.35.1
 	k8s.io/gengo/v2 v2.0.0-20250922181213-ec3ebc5fd46b
-	k8s.io/klog/v2 v2.130.1
+	k8s.io/klog/v2 v2.140.0
 )
 
 require (

staging/src/github.com/kcp-dev/code-generator/go.sum

@@ -16,5 +16,5 @@ k8s.io/code-generator v0.35.1 h1:yLKR2la7Z9cWT5qmk67ayx8xXLM4RRKQMnC8YPvTWRI=
 k8s.io/code-generator v0.35.1/go.mod h1:F2Fhm7aA69tC/VkMXLDokdovltXEF026Tb9yfQXQWKg=
 k8s.io/gengo/v2 v2.0.0-20250922181213-ec3ebc5fd46b h1:gMplByicHV/TJBizHd9aVEsTYoJBnnUAT5MHlTkbjhQ=
 k8s.io/gengo/v2 v2.0.0-20250922181213-ec3ebc5fd46b/go.mod h1:CgujABENc3KuTrcsdpGmrrASjtQsWCT7R99mEV4U/fM=
-k8s.io/klog/v2 v2.130.1 h1:n9Xl7H1Xvksem4KFG4PYbdQCQxqc/tTUyrgXaOhHSzk=
-k8s.io/klog/v2 v2.130.1/go.mod h1:3Jpz1GvMt720eyJH1ckRHK1EDfpxISzJ7I9OYgaDtPE=
+k8s.io/klog/v2 v2.140.0 h1:Tf+J3AH7xnUzZyVVXhTgGhEKnFqye14aadWv7bzXdzc=
+k8s.io/klog/v2 v2.140.0/go.mod h1:o+/RWfJ6PwpnFn7OyAG3QnO47BFsymfEfrz6XyYSSp0=