alibaba/kt-connect

package util

import (
    "github.com/rs/zerolog/log"
    "io"
    "io/fs"
    "io/ioutil"
    "os"
    "path"
    "strings"
    "time"
)

const logFilePrefix = "kt-"

var BackgroundLogger = io.Discard

func PrepareLogger(enable bool) {
    if !enable {
        return
    }
    if tmpFile, err := ioutil.TempFile(os.TempDir(), logFilePrefix); err != nil {
        log.Warn().Err(err).Msgf("Cannot create background log file")
    } else {
        log.Debug().Msgf("Background task log to %s", tmpFile.Name())
        FixFileOwner(tmpFile.Name())
        BackgroundLogger = FileWriter{tmpFile}
    }
}

type FileWriter struct {
    file *os.File
}

// Write log text
func (f FileWriter) Write(p []byte) (n int, err error) {
    return f.file.Write(p)
}

// CleanBackgroundLogs delete expired log files
func CleanBackgroundLogs() {
    files, err := ioutil.ReadDir(os.TempDir())
    if err != nil {
        log.Warn().Msgf("Failed to list background logs")
        return
    }
    for _, f := range files {
        if strings.HasPrefix(f.Name(), logFilePrefix) && isExpired(f) {
            err = os.Remove(path.Join(os.TempDir(), f.Name()))
            if err != nil {
                log.Debug().Err(err).Msgf("Failed to removed expired log %s", f.Name())
            } else {
                log.Debug().Msgf("Removed expired log %s", f.Name())
            }
        }
    }
}

// isExpired check whether file haven't been modified over 24 hours
func isExpired(info fs.FileInfo) bool {
    return info.ModTime().Unix() < time.Now().Unix() - (3600 * 24)
}