實現日誌輪播功能

// main.go
package main

import (
	"log"
	"time"
)

const logFileName = "libo"

func init() {
	log.Println("init log ...")
	setupLog()
	//time.Sleep(3 * time.Second)
	log.Println("this is output ...")
}

func main() {
	log.Println("- - - - - - - - - - - - - - -")
	log.Println("daemon started")

	go worker()

	time.Sleep(3 * time.Second)
	stop <- struct{}{}
	log.Println("daemon terminated")
}

func setupLog() {
	log.SetPrefix("[log] ")
	log.SetFlags(log.Lshortfile | log.LstdFlags)

	lf, err := NewLogFile(logFileName, nil)
	if err != nil {
		log.Fatal("Unable to create log file: ", err)
	}
	log.SetOutput(lf)

	// rotate log every 30 seconds.
	rotateLogSignal := time.Tick(2 * time.Second)
	go func() {
		for {
			<-rotateLogSignal
			if err := lf.Rotate(); err != nil {
				log.Fatal("Unable to rotate log: ", err)
			}
		}
	}()
}

var (
	stop = make(chan struct{})
)

func worker() {
	for {
		// spam to log every one second (as payload).
		log.Print("+ ", time.Now().Unix())
		time.Sleep(time.Second)

		select {
		case <-stop:
			return
		default:
		}
	}
}

說明

一個簡單的 go 日誌輪播功能，沒有特別的之處，主要是配合 channel/log/timer 實現日誌自動備份