GO 日志追加记录

以追加的方式将程序输出到不同的日志文件，当日志文件超过10M大小时，自动清空文件。

package tools

import (
    "fmt"
    "log"
    "os"
)

const logDir string = "/usr/local/dbmng/log/"

func PathExists(path string) bool {
    _, err := os.Stat(path)
    if err == nil {
        return true
    }
    if os.IsNotExist(err) {
        return false
    }
    return false
}

func CreateDir(dir string) {
    if !PathExists(dir) {
        err := os.Mkdir(dir, os.ModePerm)
        if err != nil {
            fmt.Printf("mkdir failed![%v]\n", err)
        }
    }
}
//日志分类，不同用途的日志记录于不同的文件
func LogInfo(msg string) {
    fileName := "/usr/local/dbmng/log/info.log"
    //logFile,err  := os.Create(fileName)
    LogClearFile(fileName)
    logFile, err := os.OpenFile(fileName, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
    defer logFile.Close()

    if err != nil {
        log.Fatalln("open file error")
    }
    debugLog := log.New(logFile, "[Info]", log.LstdFlags)
    debugLog.Println(msg)
}

func LogInfoDbVip(msg string) {
    fileName := "/usr/local/dbmng/log/info_dbvip.log"
    LogClearFile(fileName)
    logFile, err := os.OpenFile(fileName, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
    defer logFile.Close()

    if err != nil {
        log.Fatalln("open file error")
    }

    debugLog := log.New(logFile, "[Info]", log.LstdFlags)
    debugLog.Println(msg)
}

// 日志大于10M 时清空一次，目录不存在时会自动创建，没有测试父级目录不存在会不会创建
func LogClearFile(fileName string) {
    CreateDir(logDir)
    if PathExists(fileName) {
        fileInfo, _ := os.Stat(fileName)
        //文件大小
        filesize := fileInfo.Size()
        if filesize > 12328960 { // 大于10M时清空一次
            os.Create(fileName)
        }
    }
}

func LogWarning(msg string) {
    fileName := "/usr/local/dbmng/log/warning.log"
    LogClearFile(fileName)
    logFile, err := os.OpenFile(fileName, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
    defer logFile.Close()

    if err != nil {
        log.Fatalln("open file error")
    }
    debugLog := log.New(logFile, "[Warning]", log.LstdFlags)
    debugLog.Println(msg)
}

func showUsing() {
    fileName := "Info_First.log"
    logFile, err := os.Create(fileName)
    defer logFile.Close()
    if err != nil {
        log.Fatalln("open file error")
    }
    debugLog := log.New(logFile, "[Info]", log.Llongfile)
    debugLog.Println("A Info message here")
    debugLog.SetPrefix("[Debug]")
    debugLog.Println("A Debug Message here ")
}

/*
func main(){
    LogInfo("普通测试")
    LogInfoDbVip("第一次测试 ")
    LogWarning("第二次测试 ")
}
*/