go-logger-scaffold

go-logger-scaffold

🚀 Scaffolding for Easy setup that Json Logger and Log File Rotation to golang projects.

Features

Output json structured log to file.

• You can also output information about the number of lines in the file, the method, the host, and the git version. also version is can setting from go command.
• These can be useful for debugging
• Easily change the settings. (logger/logger.go) .
• Since it is a json structure, you can use the jq command to extract only the data you need.
• Using zap.

Output simple log to console.

• It's hard to know what's going on when the console is flood with logs.
• The output to the console is minimal information.
• Display log level and message with color.
• It can jump to Code from GoLand console log. (this is why use the standard log for console log, not zap.)
• Using log.

Log file rotation.

• Using file-rotatelogs.

Install

go get -u github.com/nkmr-jp/go-logger-scaffold/logger

How to use

Please refer to main.go

package main

import (
	"github.com/nkmr-jp/go-logger-scaffold/logger"
	"go.uber.org/zap"
)

func main() {
	logger.InitLogger()
	defer logger.Sync() // flush log buffer

	logger.Info("USER_INFO", zap.String("name", "Alice"), zap.Int("age", 20))
}

Options

following options can use.

Please refer to main.go and logger/options.go

logger.SetLogFile("./log/app_%Y-%m-%d.log")
logger.SetVersion(version)
logger.SetRepositoryCallerEncoder(urlFormat, version, srcRootDir)
logger.SetConsoleField(consoleField, traceIDField)
logger.SetLogLevel(zapcore.DebugLevel)
logger.SetOutputType(logger.OutputTypeShortConsoleAndFile)

Output

Console

$ go run main.go
2020/09/27 03:29:37 logger.go:26: [INFO] INIT_LOGGER
2020/09/27 03:29:37 main.go:10: [INFO] USER_INFO

File

ls log/
app-2020-09-27_03.log

jq example

# jq command install
$ brew install jq

# Extract only [INFO]
$ tail -fq log/*.log | jq -R 'fromjson? | select(.level=="INFO")'
{
  "level": "INFO",
  "ts": "2020-09-27T03:29:37.063635+09:00",
  "caller": "logger/logger.go:26",
  "function": "github.com/nkmr-jp/go-zap-scaffold/logger.InitLogger.func1",
  "msg": "INIT_LOGGER",
  "version": "ff97115",
  "hostname": "MacBook-Pro-16-inch-2019.local"
}
{
  "level": "INFO",
  "ts": "2020-09-27T03:29:37.064071+09:00",
  "caller": "go-logger-scaffold/main.go:10",
  "function": "main.main",
  "msg": "USER_INFO",
  "version": "ff97115",
  "hostname": "MacBook-Pro-16-inch-2019.local",
  "name": "Alice",
  "age": 20
}

Scaffolding (when you want to edit logger setting details)

cd [your-project-path]
curl -sSf https://raw.githubusercontent.com/nkmr-jp/go-logger-scaffold/master/scaffold.sh | sh
git add .
git commit -m "Create logger from https://github.com/nkmr-jp/go-logger-scaffold"

Reference

• zap package · pkg.go.dev
• golangの高速な構造化ログライブラリ「zap」の使い方 - Qiita
• Adding Caller Depth support · Issue #715 · uber-go/zap · GitHub
• logging - Is it possible to wrap log.Logger functions without losing the line number prefix? - Stack Overflow
• Time based log file rotation with zap — Dhwaneet Bhatt