logrus

# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/> [![Build Status](https://github.com/sirupsen/logrus/workflows/CI/badge.svg)](https://github.com/sirupsen/logrus/actions?query=workflow%3ACI) [![Go Reference](https://pkg.go.dev/badge/github.com/sirupsen/logrus.svg)](https://pkg.go.dev/github.com/sirupsen/logrus)

Logrus is a structured logger for Go (golang), completely API compatible with
the standard library logger.

**Logrus is in maintenance mode.** The project focuses on security, bug fixes,
and performance improvements. New features are not planned, aside from changes
required to provide interoperability with other logging ecosystems (e.g., Go's
[log/slog](https://pkg.go.dev/log/slog)).

I believe Logrus' biggest contribution is to have played a part in today's
widespread use of structured logging in Golang. There doesn't seem to be a
reason to do a major, breaking iteration into Logrus V2, since the fantastic Go
community has built those independently. Many fantastic alternatives have sprung
up. Logrus would look like those, had it been re-designed with what we know
about structured logging in Go today. Check out, for example,
[Zerolog][zerolog], [Zap][zap], and [Apex][apex].

[zerolog]: https://github.com/rs/zerolog
[zap]: https://github.com/uber-go/zap
[apex]: https://github.com/apex/log

Nicely color-coded in development (when a TTY is attached, otherwise just
plain text):

![Colored](http://i.imgur.com/PY7qMwd.png)

With `logrus.SetFormatter(&logrus.JSONFormatter{})`, for easy parsing by logstash
or Splunk:

```json lines
{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"}
{"level":"warning","msg":"The group's number increased tremendously!","number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"}
{"animal":"walrus","level":"info","msg":"A giant walrus appears!","size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"}
{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.","size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"}
{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true,"time":"2014-03-10 19:57:38.562543128 -0400 EDT"}
```

With the default `logrus.SetFormatter(&logrus.TextFormatter{})` when a TTY is not
attached, the output is compatible with the
[logfmt](https://pkg.go.dev/github.com/kr/logfmt) format:

```bash
time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8
time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true
time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4
time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009