We are going to use https://github.com/lestrrat/go-file-rotatelogs for log rotation.

Example: In the example below we are setting

• MaxAge to 10 seconds. It sets the max-age of a log file before it is purged from the file system. Meaning the file will be deleted after 10 seconds. See

rotatelogs.WithMaxAge(time.Second*10)

• RotationTime is 1 second. It sets the time when the file will be rotated. So the file will be rotated every second. See

rotatelogs.WithRotationTime(time.Second*1)

• Location is /var/log/service/ . See

path := "/var/log/service/"

• Pattern of the file is “old.UTC..2019-11-30.22:40:10” . See

 fmt.Sprintf("%s.%s", path, "%Y-%m-%d.%H:%M:%S")

• Link Path is/var/log/service/current. This file would be a symlink for the actual file. See

rotatelogs.WithLinkName("/var/log/service/current")

Code:

package main

import (
    "fmt"
    "log"
    "time"
    rotatelogs "github.com/lestrrat/go-file-rotatelogs"
    "github.com/sirupsen/logrus"
)

func initiLogger() {
    path := "/var/log/service/old.UTC."
    writer, err := rotatelogs.New(
        fmt.Sprintf("%s.%s", path, "%Y-%m-%d.%H:%M:%S"),
        rotatelogs.WithLinkName("/var/log/service/current"),
        rotatelogs.WithMaxAge(time.Second*10),
        rotatelogs.WithRotationTime(time.Second*1),
    )
    if err != nil {
        log.Fatalf("Failed to Initialize Log File %s", err)
    }
    log.SetOutput(writer)
    return
}

func main() {
    initiLogger()
    for i := 0; i < 100; i++ {
        time.Sleep(time.Second * 1)
        log.Printf("Hello, World!")
    }
    fmt.Scanln()
}

Go to the location /var/log/service/. You will notice

• Files are rotated every second.
• Max age of the file is 10 seconds. So every file will be deleted after 10 seconds.

The post Go Logger Rotation appeared first on Welcome To Golang By Example.