file.go

package zslog

import (
	"os"
	"path/filepath"

	"github.com/rs/zerolog"
	"gopkg.in/natefinch/lumberjack.v2"
)

type FileConfig struct {
	// MaxSize is the maximum size in megabytes of the log file before it gets
	// rotated. It defaults to 100 megabytes.
	MaxSize int

	// MaxAge is the maximum number of days to retain old log files based on the
	// timestamp encoded in their filename.  Note that a day is defined as 24
	// hours and may not exactly correspond to calendar days due to daylight
	// savings, leap seconds, etc. The default is not to remove old log files
	// based on age.
	MaxAge int

	// MaxBackups is the maximum number of old log files to retain.  The default
	// is to retain all old log files (though MaxAge may still cause them to get
	// deleted.)
	MaxBackups int

	// LocalTime determines if the time used for formatting the timestamps in
	// backup files is the computer's local time.  The default is to use UTC
	// time.
	LocalTime bool

	// Compress determines if the rotated log files should be compressed
	// using gzip. The default is not to perform compression.
	Compress bool
}

func File(filename string, c FileConfig, l levels) zerolog.LevelWriter {
	if err := os.MkdirAll(filepath.Dir(filename), 0744); err != nil {
		logger.Error().Err(err).Str("path", filepath.Dir(filename)).Msg("can't create log directory")
		return nil
	}
	file := &lumberjack.Logger{
		Filename:   filename,
		MaxSize:    c.MaxSize,
		MaxBackups: c.MaxBackups,
		MaxAge:     c.MaxAge,
		Compress:   c.Compress,
		LocalTime:  c.LocalTime,
	}
	lw := &LevelWriter{
		writer: file,
		levels: l,
	}
	return lw
}