logger.go

package gott

import (
	"net/url"

	"go.uber.org/zap"
	"gopkg.in/natefinch/lumberjack.v2"
)

type lumberjackSink struct {
	*lumberjack.Logger
}

// Sync implements zap.Sink. The remaining methods are implemented
// by the embedded *lumberjack.Logger.
func (lumberjackSink) Sync() error { return nil }

// NewLogger initializes a new zap.Logger with lumberjack support
// to write to log files with rotation.
func NewLogger(cnf loggingConfig) *zap.Logger {
	_ = zap.RegisterSink("lumberjack", func(u *url.URL) (zap.Sink, error) {
		return lumberjackSink{
			Logger: &lumberjack.Logger{
				Filename:   u.Opaque,
				MaxSize:    cnf.MaxSize, // megabytes
				MaxBackups: cnf.MaxBackups,
				MaxAge:     cnf.MaxAge, //days
				Compress:   cnf.EnableCompression,
			},
		}, nil
	})

	config := zap.NewDevelopmentConfig()
	config.OutputPaths = []string{"lumberjack:logs/" + cnf.Filename}
	config.DisableCaller = true
	config.Level.SetLevel(cnf.logLevel)

	logger, _ := config.Build()
	return logger
}