vendor: revendor metrics-server, custom-metrics-apiserver

vendor/k8s.io/component-base/logs/options.go

@@ -0,0 +1,126 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package logs
+
+import (
+	"flag"
+	"fmt"
+	"strings"
+
+	"github.com/go-logr/logr"
+	"github.com/spf13/pflag"
+
+	"k8s.io/klog/v2"
+)
+
+const (
+	logFormatFlagName = "logging-format"
+	defaultLogFormat  = "text"
+)
+
+// List of logs (k8s.io/klog + k8s.io/component-base/logs) flags supported by all logging formats
+var supportedLogsFlags = map[string]struct{}{
+	"v": {},
+	// TODO: support vmodule after 1.19 Alpha
+}
+
+// Options has klog format parameters
+type Options struct {
+	LogFormat string
+}
+
+// NewOptions return new klog options
+func NewOptions() *Options {
+	return &Options{
+		LogFormat: defaultLogFormat,
+	}
+}
+
+// Validate verifies if any unsupported flag is set
+// for non-default logging format
+func (o *Options) Validate() []error {
+	errs := []error{}
+	if o.LogFormat != defaultLogFormat {
+		allFlags := unsupportedLoggingFlags()
+		for _, fname := range allFlags {
+			if flagIsSet(fname) {
+				errs = append(errs, fmt.Errorf("non-default logging format doesn't honor flag: %s", fname))
+			}
+		}
+	}
+	if _, err := o.Get(); err != nil {
+		errs = append(errs, fmt.Errorf("unsupported log format: %s", o.LogFormat))
+	}
+	return errs
+}
+
+func flagIsSet(name string) bool {
+	f := flag.Lookup(name)
+	if f != nil {
+		return f.DefValue != f.Value.String()
+	}
+	pf := pflag.Lookup(name)
+	if pf != nil {
+		return pf.DefValue != pf.Value.String()
+	}
+	panic("failed to lookup unsupported log flag")
+}
+
+// AddFlags add logging-format flag
+func (o *Options) AddFlags(fs *pflag.FlagSet) {
+	unsupportedFlags := fmt.Sprintf("--%s", strings.Join(unsupportedLoggingFlags(), ", --"))
+	formats := fmt.Sprintf(`"%s"`, strings.Join(logRegistry.List(), `", "`))
+	fs.StringVar(&o.LogFormat, logFormatFlagName, defaultLogFormat, fmt.Sprintf("Sets the log format. Permitted formats: %s.\nNon-default formats don't honor these flags: %s.\nNon-default choices are currently alpha and subject to change without warning.", formats, unsupportedFlags))
+
+	// No new log formats should be added after generation is of flag options
+	logRegistry.Freeze()
+}
+
+// Apply set klog logger from LogFormat type
+func (o *Options) Apply() {
+	// if log format not exists, use nil loggr
+	loggr, _ := o.Get()
+	klog.SetLogger(loggr)
+}
+
+// Get logger with LogFormat field
+func (o *Options) Get() (logr.Logger, error) {
+	return logRegistry.Get(o.LogFormat)
+}
+
+func unsupportedLoggingFlags() []string {
+	allFlags := []string{}
+
+	// k8s.io/klog flags
+	fs := &flag.FlagSet{}
+	klog.InitFlags(fs)
+	fs.VisitAll(func(flag *flag.Flag) {
+		if _, found := supportedLogsFlags[flag.Name]; !found {
+			allFlags = append(allFlags, flag.Name)
+		}
+	})
+
+	// k8s.io/component-base/logs flags
+	pfs := &pflag.FlagSet{}
+	AddFlags(pfs)
+	pfs.VisitAll(func(flag *pflag.Flag) {
+		if _, found := supportedLogsFlags[flag.Name]; !found {
+			allFlags = append(allFlags, flag.Name)
+		}
+	})
+	return allFlags
+}