log: support maxBackups in config.toml (#2186)

log/async_file_writer.go

@@ -10,6 +10,8 @@ import (
 	"time"
 )
 
+const backupTimeFormat = "2006-01-02_15"
+
 type TimeTicker struct {
 	stop chan struct{}
 	C    <-chan time.Time
@@ -69,19 +71,24 @@ type AsyncFileWriter struct {
 	buf        chan []byte
 	stop       chan struct{}
 	timeTicker *TimeTicker
+
+	rotateHours uint
+	maxBackups  int
 }
 
-func NewAsyncFileWriter(filePath string, maxBytesSize int64, rotateHours uint) *AsyncFileWriter {
+func NewAsyncFileWriter(filePath string, maxBytesSize int64, maxBackups int, rotateHours uint) *AsyncFileWriter {
 	absFilePath, err := filepath.Abs(filePath)
 	if err != nil {
 		panic(fmt.Sprintf("get file path of logger error. filePath=%s, err=%s", filePath, err))
 	}
 
 	return &AsyncFileWriter{
-		filePath:   absFilePath,
-		buf:        make(chan []byte, maxBytesSize),
-		stop:       make(chan struct{}),
-		timeTicker: NewTimeTicker(rotateHours),
+		filePath:    absFilePath,
+		buf:         make(chan []byte, maxBytesSize),
+		stop:        make(chan struct{}),
+		rotateHours: rotateHours,
+		maxBackups:  maxBackups,
+		timeTicker:  NewTimeTicker(rotateHours),
 	}
 }
 
@@ -178,6 +185,9 @@ func (w *AsyncFileWriter) rotateFile() {
 		if err := w.initLogFile(); err != nil {
 			fmt.Fprintf(os.Stderr, "init log file error. err=%s", err)
 		}
+		if err := w.removeExpiredFile(); err != nil {
+			fmt.Fprintf(os.Stderr, "remove expired file error. err=%s", err)
+		}
 	default:
 	}
 }
@@ -222,5 +232,29 @@ func (w *AsyncFileWriter) flushAndClose() error {
 }
 
 func (w *AsyncFileWriter) timeFilePath(filePath string) string {
-	return filePath + "." + time.Now().Format("2006-01-02_15")
+	return filePath + "." + time.Now().Format(backupTimeFormat)
+}
+
+func (w *AsyncFileWriter) getExpiredFile(filePath string, maxBackups int, rotateHours uint) string {
+	if rotateHours > 0 {
+		maxBackups = int(rotateHours) * maxBackups
+	}
+	return filePath + "." + time.Now().Add(-time.Hour*time.Duration(maxBackups)).Format(backupTimeFormat)
+}
+
+func (w *AsyncFileWriter) removeExpiredFile() error {
+	if w.maxBackups == 0 {
+		return nil
+	}
+
+	oldFilepath := w.getExpiredFile(w.filePath, w.maxBackups, w.rotateHours)
+	_, err := os.Stat(oldFilepath)
+	if os.IsNotExist(err) {
+		return nil
+	}
+	errRemove := os.Remove(oldFilepath)
+	if err != nil {
+		return errRemove
+	}
+	return err
 }

log/async_file_writer_test.go

@@ -6,10 +6,12 @@ import (
 	"strings"
 	"testing"
 	"time"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestWriterHourly(t *testing.T) {
-	w := NewAsyncFileWriter("./hello.log", 100, 1)
+	w := NewAsyncFileWriter("./hello.log", 100, 1, 1)
 	w.Start()
 	w.Write([]byte("hello\n"))
 	w.Write([]byte("world\n"))
@@ -67,3 +69,22 @@ func TestGetNextRotationHour(t *testing.T) {
 		t.Run("TestGetNextRotationHour_"+strconv.Itoa(i), test(tc.now, tc.delta, tc.expectedHour))
 	}
 }
+
+func TestClearBackups(t *testing.T) {
+	dir := "./test"
+	os.Mkdir(dir, 0700)
+	w := NewAsyncFileWriter("./test/bsc.log", 100, 1, 1)
+	defer os.RemoveAll(dir)
+	fakeCurrentTime := time.Now()
+	name := ""
+	data := []byte("data")
+	for i := 0; i < 5; i++ {
+		name = w.filePath + "." + fakeCurrentTime.Format(backupTimeFormat)
+		_ = os.WriteFile(name, data, 0700)
+		fakeCurrentTime = fakeCurrentTime.Add(-time.Hour * 1)
+	}
+	oldFile := w.getExpiredFile(w.filePath, w.maxBackups, w.rotateHours)
+	w.removeExpiredFile()
+	_, err := os.Stat(oldFile)
+	assert.True(t, os.IsNotExist(err))
+}

log/handler.go

@@ -75,14 +75,14 @@ func FileHandler(path string, fmtr Format) (Handler, error) {
 // RotatingFileHandler returns a handler which writes log records to file chunks
 // at the given path. When a file's size reaches the limit, the handler creates
 // a new file named after the timestamp of the first log record it will contain.
-func RotatingFileHandler(filePath string, limit uint, formatter Format, rotateHours uint) (Handler, error) {
+func RotatingFileHandler(filePath string, limit uint, maxBackups uint, formatter Format, rotateHours uint) (Handler, error) {
 	if _, err := os.Stat(path.Dir(filePath)); os.IsNotExist(err) {
 		err := os.MkdirAll(path.Dir(filePath), 0755)
 		if err != nil {
 			return nil, fmt.Errorf("could not create directory %s, %v", path.Dir(filePath), err)
 		}
 	}
-	fileWriter := NewAsyncFileWriter(filePath, int64(limit), rotateHours)
+	fileWriter := NewAsyncFileWriter(filePath, int64(limit), int(maxBackups), rotateHours)
 	fileWriter.Start()
 	return StreamHandler(fileWriter, formatter), nil
 }

log/logger.go

@@ -290,8 +290,8 @@ func (c Ctx) toArray() []interface{} {
 	return arr
 }
 
-func NewFileLvlHandler(logPath string, maxBytesSize uint, level string, rotateHours uint) Handler {
-	rfh, err := RotatingFileHandler(logPath, maxBytesSize, LogfmtFormat(), rotateHours)
+func NewFileLvlHandler(logPath string, maxBytesSize uint, maxBackups uint, level string, rotateHours uint) Handler {
+	rfh, err := RotatingFileHandler(logPath, maxBytesSize, maxBackups, LogfmtFormat(), rotateHours)
 	if err != nil {
 		panic(err)
 	}

node/config.go

@@ -513,6 +513,7 @@ type LogConfig struct {
 	MaxBytesSize *uint   `toml:",omitempty"`
 	Level        *string `toml:",omitempty"`
 	RotateHours  *uint   `toml:",omitempty"`
+	MaxBackups   *uint   `toml:",omitempty"`
 
 	// TermTimeFormat is the time format used for console logging.
 	TermTimeFormat *string `toml:",omitempty"`

node/node.go

@@ -118,7 +118,12 @@ func New(conf *Config) (*Node, error) {
 				rotateHours = *conf.LogConfig.RotateHours
 			}
 
-			log.Root().SetHandler(log.NewFileLvlHandler(logFilePath, *conf.LogConfig.MaxBytesSize, *conf.LogConfig.Level, rotateHours))
+			maxBackups := uint(0)
+			if conf.LogConfig.MaxBackups != nil {
+				maxBackups = *conf.LogConfig.MaxBackups
+			}
+
+			log.Root().SetHandler(log.NewFileLvlHandler(logFilePath, *conf.LogConfig.MaxBytesSize, maxBackups, *conf.LogConfig.Level, rotateHours))
 		}
 	}
 	if conf.Logger == nil {