[feature] implement logging format flag at component-base

refactor registry and options file

refactor with review comment

fix gofmt and golint error

run update vendor script, and refactor code

add options get method

remove invoke with logs, and log format not a global flag

fix typo

update vendor

Author: yuzhiquan

staging/src/k8s.io/component-base/go.mod

@@ -6,6 +6,7 @@ go 1.13
 
 require (
 	github.com/blang/semver v3.5.0+incompatible
+	github.com/go-logr/logr v0.1.0
 	github.com/google/go-cmp v0.4.0
 	github.com/konsorten/go-windows-terminal-sequences v1.0.2 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369 // indirect

staging/src/k8s.io/component-base/logs/BUILD

@@ -7,11 +7,16 @@ load(
 
 go_library(
     name = "go_default_library",
-    srcs = ["logs.go"],
+    srcs = [
+        "logs.go",
+        "options.go",
+        "registry.go",
+    ],
     importmap = "k8s.io/kubernetes/vendor/k8s.io/component-base/logs",
     importpath = "k8s.io/component-base/logs",
     deps = [
         "//staging/src/k8s.io/apimachinery/pkg/util/wait:go_default_library",
+        "//vendor/github.com/go-logr/logr:go_default_library",
         "//vendor/github.com/spf13/pflag:go_default_library",
         "//vendor/k8s.io/klog/v2:go_default_library",
     ],

staging/src/k8s.io/component-base/logs/options.go

@@ -0,0 +1,67 @@
+/*
+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 (
+	"fmt"
+	"github.com/go-logr/logr"
+	"github.com/spf13/pflag"
+	"k8s.io/klog/v2"
+)
+
+const (
+	logFormatFlagName = "logging-format"
+	defaultLogFormat  = "text"
+)
+
+// Options has klog format parameters
+type Options struct {
+	LogFormat string
+}
+
+// NewOptions return new klog options
+func NewOptions() *Options {
+	return &Options{
+		LogFormat: defaultLogFormat,
+	}
+}
+
+// Validate check LogFormat in registry or not
+func (o *Options) Validate() []error {
+	if _, err := o.Get(); err != nil {
+		return []error{fmt.Errorf("unsupported log format: %s", o.LogFormat)}
+	}
+	return nil
+}
+
+// AddFlags add logging-format flag
+func (o *Options) AddFlags(fs *pflag.FlagSet) {
+	fs.StringVar(&o.LogFormat, logFormatFlagName, defaultLogFormat, "Set log format")
+}
+
+// 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)
+}

staging/src/k8s.io/component-base/logs/registry.go

@@ -0,0 +1,81 @@
+/*
+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 (
+	"fmt"
+	"sync"
+
+	"github.com/go-logr/logr"
+)
+
+var logRegistry = NewLogFormatRegistry()
+
+// LogFormatRegistry store klog format registry
+type LogFormatRegistry struct {
+	registry map[string]logr.Logger
+	mu       sync.Mutex
+}
+
+// NewLogFormatRegistry return new init LogFormatRegistry struct
+func NewLogFormatRegistry() *LogFormatRegistry {
+	return &LogFormatRegistry{
+		registry: make(map[string]logr.Logger),
+		mu:       sync.Mutex{},
+	}
+}
+
+// Register new log format registry to global logRegistry
+func (lfr *LogFormatRegistry) Register(name string, logger logr.Logger) error {
+	lfr.mu.Lock()
+	defer lfr.mu.Unlock()
+	if _, ok := lfr.registry[name]; ok {
+		return fmt.Errorf("log format: %s already exists", name)
+	}
+	lfr.registry[name] = logger
+	return nil
+}
+
+// Get specified log format logger
+func (lfr *LogFormatRegistry) Get(name string) (logr.Logger, error) {
+	lfr.mu.Lock()
+	defer lfr.mu.Unlock()
+	re, ok := lfr.registry[name]
+	if !ok {
+		return nil, fmt.Errorf("log format: %s does not exists", name)
+	}
+	return re, nil
+}
+
+// Set specified log format logger
+func (lfr *LogFormatRegistry) Set(name string, logger logr.Logger) {
+	lfr.mu.Lock()
+	defer lfr.mu.Unlock()
+	lfr.registry[name] = logger
+}
+
+// Delete specified log format logger
+func (lfr *LogFormatRegistry) Delete(name string) {
+	lfr.mu.Lock()
+	defer lfr.mu.Unlock()
+	delete(lfr.registry, name)
+}
+
+func init() {
+	// Text format is default klog format
+	logRegistry.Register("text", nil)
+}