go_dreamfactory/lego/sys/log/flieout.go
2023-02-01 10:02:34 +08:00

415 lines
9.5 KiB
Go

package log
import (
"compress/gzip"
"errors"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"sort"
"strings"
"sync"
"time"
)
const (
backupTimeFormat = "2006-01-02T15-04-05.000"
compressSuffix = ".gz"
defaultMaxSize = 100
)
var (
currentTime = time.Now
osStat = os.Stat
megabyte = 1024 * 1024
)
//日志文件输出
type LogFileOut struct {
Filename string `json:"filename" yaml:"filename"` //日志文件名称
MaxSize int `json:"maxsize" yaml:"maxsize"` //日志文件的大小
CupTime time.Duration `json:"cuptime" yaml:"cuptime"` //日志切割间隔时间
MaxAge int `json:"maxage" yaml:"maxage"` //日志的最大备份天数
MaxBackups int `json:"maxbackups" yaml:"maxbackups"` //备份日志的最大数量
LocalTime bool `json:"localtime" yaml:"localtime"` //是使用本地时间还是使用世界标准时间
Compress bool `json:"compress" yaml:"compress"` //是否压缩备份日志
UniqueLog bool `json:"uniquelog" yaml:"uniquelog"` //是否唯一日志文件
size int64
ctime time.Time
file *os.File
mu sync.Mutex
millCh chan bool
startMill sync.Once
}
func (l *LogFileOut) filename() string {
if l.Filename != "" {
return l.Filename
}
name := filepath.Base(os.Args[0]) + "-lumberjack.log"
return filepath.Join(os.TempDir(), name)
}
func (l *LogFileOut) dir() string {
return filepath.Dir(l.filename())
}
func (l *LogFileOut) max() int64 {
if l.MaxSize == 0 {
return int64(defaultMaxSize * megabyte)
}
return int64(l.MaxSize) * int64(megabyte)
}
func (l *LogFileOut) Write(p []byte) (n int, err error) {
l.mu.Lock()
defer l.mu.Unlock()
writeLen := int64(len(p))
if writeLen > l.max() {
return 0, fmt.Errorf(
"write length %d exceeds maximum file size %d", writeLen, l.max(),
)
}
if l.file == nil {
if err = l.openExistingOrNew(len(p)); err != nil {
return 0, err
}
}
n, err = l.file.Write(p)
l.size += int64(n)
return n, err
}
func (this *LogFileOut) openExistingOrNew(writeLen int) error {
this.mill()
filename := this.filename()
info, err := osStat(filename)
if os.IsNotExist(err) {
return this.openNew()
}
if err != nil {
return fmt.Errorf("error getting log file info: %s", err)
}
//校验是否需要切割日志
if !this.UniqueLog && (info.Size()+int64(writeLen) >= this.max() || (!this.ctime.IsZero() && time.Since(this.ctime) > this.CupTime)) {
return this.rotate()
}
mode := os.FileMode(0666)
if !this.UniqueLog {
file, err := os.OpenFile(filename, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, mode)
if err != nil {
// if we fail to open the old log file for some reason, just ignore
// it and open a new log file.
return this.openNew()
}
this.file = file
this.size = info.Size()
} else {
//最佳写入
f, err := os.OpenFile(filename, os.O_APPEND|os.O_CREATE|os.O_WRONLY, mode)
if err != nil {
return fmt.Errorf("can't open new logfile: %s", err)
}
this.file = f
this.size = 0
this.ctime = currentTime()
}
return nil
}
//日志切割
func (l *LogFileOut) rotate() error {
if err := l.close(); err != nil {
return err
}
if err := l.openNew(); err != nil {
return err
}
l.mill()
return nil
}
func (l *LogFileOut) millRunOnce() error {
if l.MaxBackups == 0 && l.MaxAge == 0 && !l.Compress {
return nil
}
files, err := l.oldLogFiles()
if err != nil {
return err
}
var compress, remove []logInfo
if l.MaxBackups > 0 && l.MaxBackups < len(files) {
preserved := make(map[string]bool)
var remaining []logInfo
for _, f := range files {
// Only count the uncompressed log file or the
// compressed log file, not both.
fn := f.Name()
if strings.HasSuffix(fn, compressSuffix) {
fn = fn[:len(fn)-len(compressSuffix)]
}
preserved[fn] = true
if len(preserved) > l.MaxBackups {
remove = append(remove, f)
} else {
remaining = append(remaining, f)
}
}
files = remaining
}
if l.MaxAge > 0 {
diff := time.Duration(int64(24*time.Hour) * int64(l.MaxAge))
cutoff := currentTime().Add(-1 * diff)
var remaining []logInfo
for _, f := range files {
if f.timestamp.Before(cutoff) {
remove = append(remove, f)
} else {
remaining = append(remaining, f)
}
}
files = remaining
}
if l.Compress {
for _, f := range files {
if !strings.HasSuffix(f.Name(), compressSuffix) {
compress = append(compress, f)
}
}
}
for _, f := range remove {
errRemove := os.Remove(filepath.Join(l.dir(), f.Name()))
if err == nil && errRemove != nil {
err = errRemove
}
}
for _, f := range compress {
fn := filepath.Join(l.dir(), f.Name())
errCompress := compressLogFile(fn, fn+compressSuffix)
if err == nil && errCompress != nil {
err = errCompress
}
}
return err
}
func (l *LogFileOut) millRun() {
for range l.millCh {
// what am I going to do, log this?
_ = l.millRunOnce()
}
}
//触发日志备份管理
func (l *LogFileOut) mill() {
l.startMill.Do(func() {
l.millCh = make(chan bool, 1)
go l.millRun()
})
select {
case l.millCh <- true:
default:
}
}
//备份老的日志文件创建新的日志文件
func (this *LogFileOut) openNew() error {
err := os.MkdirAll(this.dir(), 0755)
if err != nil {
return fmt.Errorf("can't make directories for new logfile: %s", err)
}
name := this.filename()
mode := os.FileMode(0666)
info, err := osStat(name)
//备份老的日志文件
if !this.UniqueLog && err == nil {
// Copy the mode off the old logfile.
mode = info.Mode()
// move the existing file
newname := backupName(name, this.LocalTime)
if err := os.Rename(name, newname); err != nil {
return fmt.Errorf("can't rename log file: %s", err)
}
// this is a no-op anywhere but linux
if err := chown(name, info); err != nil {
return err
}
}
if !this.UniqueLog {
//创建新的日志文件
f, err := os.OpenFile(name, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, mode)
if err != nil {
return fmt.Errorf("can't open new logfile: %s", err)
}
this.file = f
this.size = 0
this.ctime = currentTime()
} else {
//最佳写入
f, err := os.OpenFile(name, os.O_APPEND|os.O_CREATE|os.O_WRONLY, mode)
if err != nil {
return fmt.Errorf("can't open new logfile: %s", err)
}
this.file = f
this.size = 0
this.ctime = currentTime()
}
return nil
}
//关闭当前日志文件
func (l *LogFileOut) close() error {
if l.file == nil {
return nil
}
err := l.file.Close()
l.file = nil
return err
}
//获取备份的日子文件集合
func (l *LogFileOut) oldLogFiles() ([]logInfo, error) {
files, err := ioutil.ReadDir(l.dir())
if err != nil {
return nil, fmt.Errorf("can't read log file directory: %s", err)
}
logFiles := []logInfo{}
prefix, ext := l.prefixAndExt()
for _, f := range files {
if f.IsDir() {
continue
}
if t, err := l.timeFromName(f.Name(), prefix, ext); err == nil {
logFiles = append(logFiles, logInfo{t, f})
continue
}
if t, err := l.timeFromName(f.Name(), prefix, ext+compressSuffix); err == nil {
logFiles = append(logFiles, logInfo{t, f})
continue
}
// error parsing means that the suffix at the end was not generated
// by lumberjack, and therefore it's not a backup file.
}
sort.Sort(byFormatTime(logFiles))
return logFiles, nil
}
func (l *LogFileOut) prefixAndExt() (prefix, ext string) {
filename := filepath.Base(l.filename())
ext = filepath.Ext(filename)
prefix = filename[:len(filename)-len(ext)] + "-"
return prefix, ext
}
func (l *LogFileOut) timeFromName(filename, prefix, ext string) (time.Time, error) {
if !strings.HasPrefix(filename, prefix) {
return time.Time{}, errors.New("mismatched prefix")
}
if !strings.HasSuffix(filename, ext) {
return time.Time{}, errors.New("mismatched extension")
}
ts := filename[len(prefix) : len(filename)-len(ext)]
return time.Parse(backupTimeFormat, ts)
}
//日志备份名
func backupName(name string, local bool) string {
dir := filepath.Dir(name)
filename := filepath.Base(name)
ext := filepath.Ext(filename)
prefix := filename[:len(filename)-len(ext)]
t := currentTime()
if !local {
t = t.UTC()
}
timestamp := t.Format(backupTimeFormat)
return filepath.Join(dir, fmt.Sprintf("%s-%s%s", prefix, timestamp, ext))
}
//压缩日志文件
func compressLogFile(src, dst string) (err error) {
f, err := os.Open(src)
if err != nil {
return fmt.Errorf("failed to open log file: %v", err)
}
defer f.Close()
fi, err := osStat(src)
if err != nil {
return fmt.Errorf("failed to stat log file: %v", err)
}
if err := chown(dst, fi); err != nil {
return fmt.Errorf("failed to chown compressed log file: %v", err)
}
// If this file already exists, we presume it was created by
// a previous attempt to compress the log file.
gzf, err := os.OpenFile(dst, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, fi.Mode())
if err != nil {
return fmt.Errorf("failed to open compressed log file: %v", err)
}
defer gzf.Close()
gz := gzip.NewWriter(gzf)
defer func() {
if err != nil {
os.Remove(dst)
err = fmt.Errorf("failed to compress log file: %v", err)
}
}()
if _, err := io.Copy(gz, f); err != nil {
return err
}
if err := gz.Close(); err != nil {
return err
}
if err := gzf.Close(); err != nil {
return err
}
if err := f.Close(); err != nil {
return err
}
if err := os.Remove(src); err != nil {
return err
}
return nil
}
type logInfo struct {
timestamp time.Time
os.FileInfo
}
type byFormatTime []logInfo
func (b byFormatTime) Less(i, j int) bool {
return b[i].timestamp.After(b[j].timestamp)
}
func (b byFormatTime) Swap(i, j int) {
b[i], b[j] = b[j], b[i]
}
func (b byFormatTime) Len() int {
return len(b)
}