Awesome

Structured logging for golang

Package log implements a simple structured logging API inspired by Logrus, designed with centralization in mind. Read more on Medium.

Handlers

apexlogs – handler for Apex Logs
cli – human-friendly CLI output
discard – discards all logs
es – Elasticsearch handler
graylog – Graylog handler
json – JSON output handler
kinesis – AWS Kinesis handler
level – level filter handler
logfmt – logfmt plain-text formatter
memory – in-memory handler for tests
multi – fan-out to multiple handlers
papertrail – Papertrail handler
text – human-friendly colored output
delta – outputs the delta between log calls and spinner

Example

Example using the Apex Logs handler.

package main

import (
	"errors"
	"time"

	"github.com/apex/log"
)

func main() {
	ctx := log.WithFields(log.Fields{
		"file": "something.png",
		"type": "image/png",
		"user": "tobi",
	})

	for range time.Tick(time.Millisecond * 200) {
		ctx.Info("upload")
		ctx.Info("upload complete")
		ctx.Warn("upload retry")
		ctx.WithError(errors.New("unauthorized")).Error("upload failed")
		ctx.Errorf("failed to upload %s", "img.png")
	}
}