Remove global klog --log-flush-frequency flag

Signed-off-by: Monis Khan <mok@vmware.com>

cmd/pinniped-supervisor/main.go

@@ -32,6 +32,7 @@ import (
 	"go.pinniped.dev/internal/oidc/jwks"
 	"go.pinniped.dev/internal/oidc/provider"
 	"go.pinniped.dev/internal/oidc/provider/manager"
+	"go.pinniped.dev/internal/plog"
 )
 
 const (
@@ -242,6 +243,7 @@ func run(serverInstallationNamespace string, cfg *supervisor.Config) error {
 func main() {
 	logs.InitLogs()
 	defer logs.FlushLogs()
+	plog.RemoveKlogGlobalFlags() // move this whenever the below code gets refactored to use cobra
 
 	klog.Infof("Running %s at %#v", rest.DefaultKubernetesUserAgent(), version.Get())
 	klog.Infof("Command-line arguments were: %s %s %s", os.Args[0], os.Args[1], os.Args[2])

internal/concierge/server/server.go

@@ -23,6 +23,7 @@ import (
 	"go.pinniped.dev/internal/downward"
 	"go.pinniped.dev/internal/dynamiccert"
 	"go.pinniped.dev/internal/here"
+	"go.pinniped.dev/internal/plog"
 	"go.pinniped.dev/internal/registry/credentialrequest"
 )
 
@@ -87,6 +88,8 @@ func addCommandlineFlagsToCommand(cmd *cobra.Command, app *App) {
 		"/etc/podinfo",
 		"path to Downward API volume mount",
 	)
+
+	plog.RemoveKlogGlobalFlags()
 }
 
 // Boot the aggregated API server, which will in turn boot the controllers.

internal/concierge/server/server_test.go

@@ -26,7 +26,6 @@ Flags:
   -c, --config string              path to configuration file (default "pinniped.yaml")
       --downward-api-path string   path to Downward API volume mount (default "/etc/podinfo")
   -h, --help                       help for pinniped-concierge
-      --log-flush-frequency duration   Maximum number of seconds between log flushes (default 5s)
 `
 
 func TestCommand(t *testing.T) {

internal/plog/klog.go

@@ -0,0 +1,21 @@
+// Copyright 2020 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package plog
+
+import "github.com/spf13/pflag"
+
+// RemoveKlogGlobalFlags attempts to "remove" flags that get unconditionally added by importing klog.
+func RemoveKlogGlobalFlags() {
+	// if this function starts to panic, it likely means that klog stopped mucking with global flags
+	const globalLogFlushFlag = "log-flush-frequency"
+	if err := pflag.CommandLine.MarkHidden(globalLogFlushFlag); err != nil {
+		panic(err)
+	}
+	if err := pflag.CommandLine.MarkDeprecated(globalLogFlushFlag, "unsupported"); err != nil {
+		panic(err)
+	}
+	if pflag.CommandLine.Changed(globalLogFlushFlag) {
+		panic("unsupported global klog flag set")
+	}
+}