feat: kubesphere 4.0 (#6115)

* feat: kubesphere 4.0

Signed-off-by: ci-bot <ci-bot@kubesphere.io>

* feat: kubesphere 4.0

Signed-off-by: ci-bot <ci-bot@kubesphere.io>

---------

Signed-off-by: ci-bot <ci-bot@kubesphere.io>
Co-authored-by: ks-ci-bot <ks-ci-bot@example.com>
Co-authored-by: joyceliu <joyceliu@yunify.com>

pkg/apiserver/auditing/log/backend.go

@@ -0,0 +1,94 @@
+/*
+ * Please refer to the LICENSE file in the root directory of the project.
+ * https://github.com/kubesphere/kubesphere/blob/master/LICENSE
+ */
+
+package log
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"time"
+
+	"gopkg.in/natefinch/lumberjack.v2"
+	"k8s.io/klog/v2"
+
+	"kubesphere.io/kubesphere/pkg/apiserver/auditing/internal"
+)
+
+const (
+	WriteTimeout      = time.Second * 3
+	DefaultMaxAge     = 7
+	DefaultMaxBackups = 10
+	DefaultMaxSize    = 100
+)
+
+type backend struct {
+	path       string
+	maxAge     int
+	maxBackups int
+	maxSize    int
+	timeout    time.Duration
+
+	writer io.Writer
+}
+
+func NewBackend(path string, maxAge, maxBackups, maxSize int) internal.Backend {
+	b := backend{
+		path:       path,
+		maxAge:     maxAge,
+		maxBackups: maxBackups,
+		maxSize:    maxSize,
+		timeout:    WriteTimeout,
+	}
+
+	if b.maxAge == 0 {
+		b.maxAge = DefaultMaxAge
+	}
+
+	if b.maxBackups == 0 {
+		b.maxBackups = DefaultMaxBackups
+	}
+
+	if b.maxSize == 0 {
+		b.maxSize = DefaultMaxSize
+	}
+
+	if err := b.ensureLogFile(); err != nil {
+		klog.Errorf("ensure audit log file error, %s", err)
+		return nil
+	}
+
+	b.writer = &lumberjack.Logger{
+		Filename:   b.path,
+		MaxAge:     b.maxAge,
+		MaxBackups: b.maxBackups,
+		MaxSize:    b.maxSize,
+		Compress:   false,
+	}
+
+	return &b
+}
+
+func (b *backend) ensureLogFile() error {
+	if err := os.MkdirAll(filepath.Dir(b.path), 0700); err != nil {
+		return err
+	}
+	mode := os.FileMode(0600)
+	f, err := os.OpenFile(b.path, os.O_CREATE|os.O_APPEND|os.O_RDWR, mode)
+	if err != nil {
+		return err
+	}
+	return f.Close()
+}
+
+func (b *backend) ProcessEvents(events ...[]byte) {
+	for _, event := range events {
+		if _, err := fmt.Fprint(b.writer, string(event)+"\n"); err != nil {
+			klog.Errorf("Log audit event error, %s. affecting audit event: %v\nImpacted event:\n", err, event)
+			klog.Error(string(event))
+		}
+	}
+}