watchFile

go-watch-file is a Go library similar to Python’sWatchedFileHandler, for writing files that may berotated, such as log rotation scenarios.

(This project is stable and generally does not require updates unless Unix system behavior changes)

go-watch-file 是一个类似 Python WatchedFileHandler 的 Go 库，用于写入可能被轮转的文件，如日志轮转场景。

（本项目已处于稳定状态，在 Unix 系统行为未发生变化的情况下通常不需要更新）

note

• only Unix systems are supported
• 仅支持 Unix 系统

version

• latest: v1.0.3

Install

go get -u github.com/gojuukaze/go-watch-file

# use go mod
go get github.com/gojuukaze/go-watch-file@v1.0.3
# or
go mod edit -require=github.com/gojuukaze/go-watch-file@v1.0.3

Example

package main

import (
	"github.com/gojuukaze/go-watch-file"
	"os"
	"fmt"
)

func main() {

	f, _ := watchFile.OpenWatchFile("./a.txt")
	f.WriteString("111")

	os.Remove("./a.txt")

	f.WriteString("222\n")
	f.Write([]byte("44"))

	f.Close()

	//
	f2, _ := watchFile.OpenWatchFile2("./b.txt", os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0666)
	f2.WriteString("333")
	f2.Close()

	// use other file method
	f3, _ := watchFile.OpenWatchFile2("./b.txt", os.O_RDONLY|os.O_CREATE, 0666)
	f3.Reopen()
	b := make([] byte, 4)
	f3.F.Read(b)
	fmt.Println(b)
	f3.Close()

}

using with logrus

set output

f,err:=watchFile.OpenWatchFile("m.log")
if err != nil {
	panic(err)
}
Log := logrus.New()
Log.SetOutput(f)

hook

type FileHook struct {
	f         *watchFile.WatchFile
	formatter logrus.Formatter
}

func (hook FileHook) Levels() []logrus.Level {
	return logrus.AllLevels
}

func (hook FileHook) Fire(entry *logrus.Entry) error {
	msg, err := hook.formatter.Format(entry)
	if err != nil {
		return err
	}
	hook.f.Write(msg)
	return nil
}

func NewFileHook(name string) FileHook {
	f, err := watchFile.OpenWatchFile(name)
	if err != nil {
		panic(err)
	}
	var hook = FileHook{
		f:         f,
		formatter: &logrus.TextFormatter{DisableColors: true},
	}
	return hook

}

Log = logrus.New()
fHook:=NewFileHook("m.log")
Log.AddHook(fHook)