log: add klog/v2

Fixes #924

Signed-off-by: Pires <pjpires@gmail.com>

go.sum

@@ -645,6 +645,7 @@ golang.org/x/lint v0.0.0-20190301231843-5614ed5bae6f/go.mod h1:UVdnD1Gm6xHRNCYTk
 golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/lint v0.0.0-20190409202823-959b441ac422 h1:QzoH/1pFpZguR8NrRHLcO6jKqfv2zpuSqZLgdm7ZmjI=
 golang.org/x/lint v0.0.0-20190409202823-959b441ac422/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
+golang.org/x/lint v0.0.0-20190930215403-16217165b5de h1:5hukYrvBGR8/eNkX5mdUezrA6JiaEZDtJb9Ei+1LlBs=
 golang.org/x/lint v0.0.0-20190930215403-16217165b5de/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/mobile v0.0.0-20190312151609-d3739f865fa6/go.mod h1:z+o9i4GpDbdi3rU15maQ/Ox0txvL9dWGYEHz965HBQE=
 golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKGUJ2LatrhH/nqhxcFungHvyanc=

log/klogv2/klogv2.go

@@ -0,0 +1,95 @@
+// Copyright © 2021 The virtual-kubelet 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 klogv2 implements a virtual-kubelet/log.Logger using klogv2 as a backend
+//
+// You can use this by creating a klogv2 logger and calling `FromKlogv2(fields)`.
+// If you want this to be the default logger for virtual-kubelet, set `log.L` to the value returned by `FromKlogv2`
+//
+// We recommend reading the klog conventions to build a better understanding of levels and when they should apply
+// https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/logging.md
+package klogv2
+
+import (
+	"github.com/virtual-kubelet/virtual-kubelet/log"
+	"k8s.io/klog/v2"
+)
+
+// adapter implements the `log.Logger` interface for klogv2
+type adapter struct {
+	fields map[string]interface{}
+}
+
+// FromKlogv2 creates a new `log.Logger` from the provided entry
+func FromKlogv2(fields map[string]interface{}) log.Logger {
+	return &adapter{fields}
+}
+
+func (l *adapter) Debug(args ...interface{}) {
+	klog.V(4).Info(args, l.fields)
+}
+
+func (l *adapter) Debugf(format string, args ...interface{}) {
+	klog.V(4).Infof(format, args, l.fields)
+}
+
+func (l *adapter) Info(args ...interface{}) {
+	klog.Info(args, l.fields)
+}
+
+func (l *adapter) Infof(format string, args ...interface{}) {
+	klog.Infof(format, args, l.fields)
+}
+
+func (l *adapter) Warn(args ...interface{}) {
+	klog.Warning(args, l.fields)
+}
+
+func (l *adapter) Warnf(format string, args ...interface{}) {
+	klog.Warningf(format, args, l.fields)
+}
+
+func (l *adapter) Error(args ...interface{}) {
+	klog.Error(args, l.fields)
+}
+
+func (l *adapter) Errorf(format string, args ...interface{}) {
+	klog.Errorf(format, args, l.fields)
+}
+
+func (l *adapter) Fatal(args ...interface{}) {
+	klog.Fatal(args, l.fields)
+}
+
+func (l *adapter) Fatalf(format string, args ...interface{}) {
+	klog.Fatalf(format, args, l.fields)
+}
+
+// WithField adds a field to the log entry.
+func (l *adapter) WithField(key string, val interface{}) log.Logger {
+	fields := map[string]interface{}{
+		key: val,
+	}
+	return FromKlogv2(fields)
+}
+
+// WithFields adds multiple fields to a log entry.
+func (l *adapter) WithFields(fields log.Fields) log.Logger {
+	return FromKlogv2(fields)
+}
+
+// WithError adds an error to the log entry
+func (l *adapter) WithError(err error) log.Logger {
+	return l.WithField("err", err)
+}

log/klogv2/klogv2_test.go

@@ -0,0 +1,28 @@
+// Copyright © 2021 The virtual-kubelet 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 klogv2
+
+import (
+	"testing"
+
+	"github.com/virtual-kubelet/virtual-kubelet/log"
+)
+
+func TestImplementsLoggerInterface(t *testing.T) {
+	l := FromKlogv2(nil)
+
+	if _, ok := l.(log.Logger); !ok {
+		t.Fatal("does not implement log.Logger interface")
+	}
+}

log/logrus/logrus.go

@@ -22,27 +22,27 @@ import (
 	"github.com/virtual-kubelet/virtual-kubelet/log"
 )
 
-// Adapter implements the `log.Logger` interface for logrus
-type Adapter struct {
+// adapter implements the `log.Logger` interface for logrus
+type adapter struct {
 	*logrus.Entry
 }
 
 // FromLogrus creates a new `log.Logger` from the provided entry
 func FromLogrus(entry *logrus.Entry) log.Logger {
-	return &Adapter{entry}
+	return &adapter{entry}
 }
 
 // WithField adds a field to the log entry.
-func (l *Adapter) WithField(key string, val interface{}) log.Logger {
+func (l *adapter) WithField(key string, val interface{}) log.Logger {
 	return FromLogrus(l.Entry.WithField(key, val))
 }
 
 // WithFields adds multiple fields to a log entry.
-func (l *Adapter) WithFields(f log.Fields) log.Logger {
+func (l *adapter) WithFields(f log.Fields) log.Logger {
 	return FromLogrus(l.Entry.WithFields(logrus.Fields(f)))
 }
 
 // WithError adds an error to the log entry
-func (l *Adapter) WithError(err error) log.Logger {
+func (l *adapter) WithError(err error) log.Logger {
 	return FromLogrus(l.Entry.WithError(err))
 }