uniugm/admin/lib/xlog/handler/handler_file_rotate.go
2025-04-18 17:17:23 +08:00

84 lines
1.6 KiB
Go

package handler
import (
"fmt"
"os"
"path"
)
// RotatingFileHandler writes xlog a file, if file size exceeds maxBytes,
// it will backup current file and open a new one.
//
// max backup file number is set by backupCount, it will delete oldest if backups too many.
type RotatingFileHandler struct {
fd *os.File
fileName string
maxBytes int
backupCount int
}
func NewRotatingFileHandler(fileName string, maxBytes int, backupCount int) (*RotatingFileHandler, error) {
dir := path.Dir(fileName)
os.Mkdir(dir, 0777)
h := new(RotatingFileHandler)
if maxBytes <= 0 {
return nil, fmt.Errorf("invalid max bytes")
}
h.fileName = fileName
h.maxBytes = maxBytes
h.backupCount = backupCount
var err error
h.fd, err = os.OpenFile(fileName, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
if err != nil {
return nil, err
}
return h, nil
}
func (h *RotatingFileHandler) Write(p []byte) (n int, err error) {
h.doRollover()
return h.fd.Write(p)
}
func (h *RotatingFileHandler) Close() error {
if h.fd != nil {
return h.fd.Close()
}
return nil
}
func (h *RotatingFileHandler) doRollover() {
f, err := h.fd.Stat()
if err != nil {
return
}
if h.maxBytes <= 0 {
return
} else if f.Size() < int64(h.maxBytes) {
return
}
if h.backupCount > 0 {
h.fd.Close()
for i := h.backupCount - 1; i > 0; i-- {
sfn := fmt.Sprintf("%s.%d", h.fileName, i)
dfn := fmt.Sprintf("%s.%d", h.fileName, i+1)
os.Rename(sfn, dfn)
}
dfn := fmt.Sprintf("%s.1", h.fileName)
os.Rename(h.fileName, dfn)
h.fd, _ = os.OpenFile(h.fileName, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
}
}