logger-file-hook.go

/*
 * Minio Cloud Storage, (C) 2015 Minio, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package main

import (
	"fmt"
	"os"

	"github.com/Sirupsen/logrus"
	"github.com/minio/minio-xl/pkg/probe"
)

type localFile struct {
	*os.File
}

func log2File(filename string) *probe.Error {
	fileHook, e := newFile(filename)
	if e != nil {
		return probe.NewError(e)
	}
	log.Hooks.Add(fileHook)                 // Add a local file hook.
	log.Formatter = &logrus.JSONFormatter{} // JSON formatted log.
	log.Level = logrus.InfoLevel            // Minimum log level.
	return nil
}

func newFile(filename string) (*localFile, error) {
	file, err := os.OpenFile(filename, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0600)
	if err != nil {
		return nil, err
	}
	return &localFile{file}, nil
}

func (l *localFile) Fire(entry *logrus.Entry) error {
	line, err := entry.String()
	if err != nil {
		return fmt.Errorf("Unable to read entry, %v", err)
	}
	l.File.Write([]byte(line + "\n"))
	l.File.Sync()
	return nil
}

// Levels -
func (l *localFile) Levels() []logrus.Level {
	return []logrus.Level{
		logrus.PanicLevel,
		logrus.FatalLevel,
		logrus.ErrorLevel,
		logrus.WarnLevel,
		logrus.InfoLevel,
		logrus.DebugLevel,
	}
}