logrus/hooks/syslog
Tommaso Visconti 70234da9c3 Add instructions to use different log levels for local and syslog
This commit adds instructions to the syslog readme about how to
send different log levels to local logging (`log.SetLevel`) and
syslog hook.

fixes #1369
2023-02-17 10:10:23 +01:00
..
README.md Add instructions to use different log levels for local and syslog 2023-02-17 10:10:23 +01:00
syslog.go Added TRACE level logging. 2018-10-17 18:22:00 -07:00
syslog_test.go Add missing module dependency for windows build 2018-09-19 13:46:16 +02:00

README.md

Syslog Hooks for Logrus :walrus:

Usage

import (
  "log/syslog"
  "github.com/sirupsen/logrus"
  lSyslog "github.com/sirupsen/logrus/hooks/syslog"
)

func main() {
  log       := logrus.New()
  hook, err := lSyslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")

  if err == nil {
    log.Hooks.Add(hook)
  }
}

If you want to connect to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). Just assign empty string to the first two parameters of NewSyslogHook. It should look like the following.

import (
  "log/syslog"
  "github.com/sirupsen/logrus"
  lSyslog "github.com/sirupsen/logrus/hooks/syslog"
)

func main() {
  log       := logrus.New()
  hook, err := lSyslog.NewSyslogHook("", "", syslog.LOG_INFO, "")

  if err == nil {
    log.Hooks.Add(hook)
  }
}

Different log levels for local and remote logging

By default NewSyslogHook() sends logs through the hook for all log levels. If you want to have different log levels between local logging and syslog logging (i.e. respect the priority argument passed to NewSyslogHook()), you need to implement the logrus_syslog.SyslogHook interface overriding Levels() to return only the log levels you're interested on.

The following example shows how to log at DEBUG level for local logging and WARN level for syslog logging:

package main

import (
	"log/syslog"

	log "github.com/sirupsen/logrus"
	logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
)

type customHook struct {
	*logrus_syslog.SyslogHook
}

func (h *customHook) Levels() []log.Level {
	return []log.Level{log.WarnLevel}
}

func main() {
	log.SetLevel(log.DebugLevel)

	hook, err := logrus_syslog.NewSyslogHook("tcp", "localhost:5140", syslog.LOG_WARNING, "myTag")
	if err != nil {
		panic(err)
	}

	log.AddHook(&customHook{hook})

	//...
}