https://github.com/slok/noglog
"Bring your own logger" replacement for github.com/golang/glog.
https://github.com/slok/noglog
glog k8s kubernetes log logger logging logs replacement
Last synced: about 2 months ago
JSON representation
"Bring your own logger" replacement for github.com/golang/glog.
- Host: GitHub
- URL: https://github.com/slok/noglog
- Owner: slok
- License: apache-2.0
- Created: 2018-09-22T07:22:12.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2021-04-22T01:18:02.000Z (about 4 years ago)
- Last Synced: 2025-03-19T08:39:26.416Z (2 months ago)
- Topics: glog, k8s, kubernetes, log, logger, logging, logs, replacement
- Language: Go
- Homepage:
- Size: 40 KB
- Stars: 12
- Watchers: 4
- Forks: 4
- Open Issues: 1
-
Metadata Files:
- Readme: Readme.md
- Changelog: CHANGELOG
- License: LICENSE
Awesome Lists containing this project
README
# noglog [![Build Status][travis-image]][travis-url] [![Go Report Card][goreport-image]][goreport-url] [![GoDoc][godoc-image]][godoc-url]
noglog is a replacement for [github.com/golang/glog][glog] implementation.
This package is a "bring you own" logger for glog replacement. It will replace all the glog calls with any logger that implements `noglog.Logger` interface.
You can go from this:
```text
ERROR: logging before flag.Parse: I0921 14:49:49.283733 1 leaderelection.go:175] attempting to acquire leader lease example-lock...
```
to this:
```text
INFO[0000] attempting to acquire leader lease example-lock... source=k8s src="leaderelection.go:175"
```
or whatever format you want (or don't show at all).
## Features
- Replace glog messages with your own logger (implement small interface and done).
- No [flags] modification.
## Getting Started
For a complete example, check [this][example]
### Import library
First we need to add noglog as dependency, but it will need to be placed on `github.com/golang/glog` import path, so `github.com/slok/noglog` code replaces `github.com/golang/glog`
#### Using go modules
```text
require (
github.com/google/glog master
)
replace (
github.com/google/glog => github.com/slok/noglog master
)
```
#### Using dep
```toml
[[override]]
name = "github.com/golang/glog"
source = "github.com/slok/noglog"
branch = "master"
```
### Set our custom logger
Import glog and the first thing that your app should do is instantiate your logger and set as the glog logger. Example:
```golang
import (
"github.com/golang/glog"
)
func main() {
// Import custom logger that satisfies noglog.Logger interface.
logger := mylogger.New()
glog.SetLogger(logger)
}
```
For security reasons if you don't set a logger, it will use a dummy logger that will disable Kubernetes logs. Sometimes this is useful also.
Your custom logger needs to satisfy `noglog.Logger` interface.
You have a helper if you want to create a logger using functions instead of creating a new type, `noglog.LoggerFunc`.
This helper gives a lot of power to set up loggers easily. Some examples...
Logrus:
```golang
import (
"github.com/google/glog"
"github.com/sirupsen/logrus"
)
func main() {
// Our app logger.
logger := logrus.New()
logger.SetLevel(logrus.DebugLevel)
// Set our glog replacement.
glog.SetLogger(&glog.LoggerFunc{
DebugfFunc: func(f string, a ...interface{}) { logger.Debugf(f, a...) },
InfofFunc: func(f string, a ...interface{}) { logger.Infof(f, a...) },
WarnfFunc: func(f string, a ...interface{}) { logger.Warnf(f, a...) },
ErrorfFunc: func(f string, a ...interface{}) { logger.Errorf(f, a...) },
})
glog.Info("I'm batman!")
}
```
Example for zap:
```golang
import (
"github.com/google/glog"
"go.uber.org/zap"
)
func main() {
// Our app logger.
logger, _ := zap.NewProduction()
slogger := logger.Sugar()
// Set our glog replacement.
glog.SetLogger(&glog.LoggerFunc{
DebugfFunc: func(f string, a ...interface{}) { slogger.Debugf(f, a...) },
InfofFunc: func(f string, a ...interface{}) { slogger.Infof(f, a...) },
WarnfFunc: func(f string, a ...interface{}) { slogger.Warnf(f, a...) },
ErrorfFunc: func(f string, a ...interface{}) { slogger.Errorf(f, a...) },
})
glog.Info("I'm batman!")
}
```
Example for zerolog:
```golang
import (
"os"
"github.com/google/glog"
"github.com/rs/zerolog"
)
func main() {
// Our app logger.
w := zerolog.ConsoleWriter{Out: os.Stderr}
logger := zerolog.New(w).With().Timestamp().Logger()
// Set our glog replacement.
glog.SetLogger(&glog.LoggerFunc{
DebugfFunc: func(f string, a ...interface{}) { logger.Debug().Msgf(f, a...) },
InfofFunc: func(f string, a ...interface{}) { logger.Info().Msgf(f, a...) },
WarnfFunc: func(f string, a ...interface{}) { logger.Warn().Msgf(f, a...) },
ErrorfFunc: func(f string, a ...interface{}) { logger.Error().Msgf(f, a...) },
})
glog.Info("I'm batman!")
}
```
## Why
Glog is a logger used on some important projects like Kubernetes, Glog modifies globals like `flag` of your program and it can't be done nothing to disable, modify...
For example in Kubernetes glog is around all the source code, they don't use a common app logger interface that it can be reimplement with any log implementation, or pass any logger as dependency injection, so the Kubernetes extensions that use [client-go] will get flags modification, unstructured logs around it well set log format lines...
## When to use noglog
- Tired of glog logs.
- Every extension/app of Kubernetes I do has annoying unstructured logs.
- My app flags have glog flags that I didn't ask for.
- `ERROR: logging before flag.Parse: W0922` WTF when using a custom `flag.FlagSet`.
## Alternatives
Although noglog can use any logger due to the simple interface, there are other alternatives that replace the logger for a specific logger with defaults, if you don't want to bring your own or customize these loggers here are the alternatives:
- [glog-logrus]
- [istio-glog](zap)
[travis-image]: https://travis-ci.org/slok/noglog.svg?branch=master
[travis-url]: https://travis-ci.org/slok/noglog
[goreport-image]: https://goreportcard.com/badge/github.com/slok/noglog
[goreport-url]: https://goreportcard.com/report/github.com/slok/noglog
[godoc-image]: https://godoc.org/github.com/slok/noglog?status.svg
[godoc-url]: https://godoc.org/github.com/slok/noglog
[glog]: https://github.com/golang/glog
[client-go]: https://github.com/kubernetes/client-go
[flags]: https://golang.org/pkg/flag
[glog-logrus]: https://github.com/kubermatic/glog-logrus
[istio-glog]: https://github.com/istio/glog
[example]: /example