利用logrus hook如何实现将日志输出到本地磁盘

logrus.Debug("Useful debugging information.")
logrus.Info("Something noteworthy happened!")
logrus.Warn("You should probably take a look at this.")
logrus.Error("Something failed but I'm not quitting.")
logrus.Fatal("Bye.")  //log之后会调用os.Exit(1)
logrus.Panic("I'm bailing.")  //log之后会panic()

package main

import (
 "fmt"
 "github.com/sirupsen/logrus"
 "logT/logS"
)
func main() {
  //创建一个hook，将日志存储路径输入进去
 hook := logS.NewHook("d:/log/golog.log")
 //加载hook之前打印日志
 logrus.WithField("file", "d:/log/golog.log").Info("New logrus hook err.")
 logrus.AddHook(hook)
 //加载hook之后打印日志
 logrus.WithFields(logrus.Fields{
 "animal": "walrus",
 }).Info("A walrus appears")
}

import (
 "fmt"
 "github.com/sirupsen/logrus"
 "os"
 "strings"
)

// Hook 写文件的Logrus Hook
type Hook struct {
 W LoggerInterface
}

func NewHook(file string) (f *Hook) {
 w := NewFileWriter()
 config := fmt.Sprintf(`{"filename":"%s","maxdays":7}`, file)
 err := w.Init(config)
 if err != nil {
 return nil
 }

 return &Hook{w}
}

// Fire 实现Hook的Fire接口
func (hook *Hook) Fire(entry *logrus.Entry) (err error) {
 message, err := getMessage(entry)
 if err != nil {
 fmt.Fprintf(os.Stderr, "Unable to read entry, %v", err)
 return err
 }
 switch entry.Level {
 case logrus.PanicLevel:
 fallthrough
 case logrus.FatalLevel:
 fallthrough
 case logrus.ErrorLevel:
 return hook.W.WriteMsg(fmt.Sprintf("[ERROR] %s", message), LevelError)
 case logrus.WarnLevel:
 return hook.W.WriteMsg(fmt.Sprintf("[WARN] %s", message), LevelWarn)
 case logrus.InfoLevel:
 return hook.W.WriteMsg(fmt.Sprintf("[INFO] %s", message), LevelInfo)
 case logrus.DebugLevel:
 return hook.W.WriteMsg(fmt.Sprintf("[DEBUG] %s", message), LevelDebug)
 default:
 return nil
 }
}

// Levels 实现Hook的Levels接口
func (hook *Hook) Levels() []logrus.Level {
 return []logrus.Level{
 logrus.PanicLevel,
 logrus.FatalLevel,
 logrus.ErrorLevel,
 logrus.WarnLevel,
 logrus.InfoLevel,
 logrus.DebugLevel,
 }
}

func getMessage(entry *logrus.Entry) (message string, err error) {
 message = message + fmt.Sprintf("%s ", entry.Message)
 file, lineNumber := GetCallerIgnoringLogMulti(2)
 if file != "" {
 sep := fmt.Sprintf("%s/src/", os.Getenv("GOPATH"))
 fileName := strings.Split(file, sep)
 if len(fileName) >= 2 {
  file = fileName[1]
 }
 }
 message = fmt.Sprintf("%s:%d ", file, lineNumber) + message

 for k, v := range entry.Data {
 message = message + fmt.Sprintf("%v:%v ", k, v)
 }
 return
}

package logS

import (
 "runtime"
 "strings"
)

func GetCaller(callDepth int, suffixesToIgnore ...string) (file string, line int) {
 // bump by 1 to ignore the getCaller (this) stackframe
 callDepth++
outer:
 for {
 var ok bool
 _, file, line, ok = runtime.Caller(callDepth)
 if !ok {
  file = "???"
  line = 0
  break
 }

 for _, s := range suffixesToIgnore {
  if strings.HasSuffix(file, s) {
  callDepth++
  continue outer
  }
 }
 break
 }
 return
}

// GetCallerIgnoringLogMulti TODO
func GetCallerIgnoringLogMulti(callDepth int) (string, int) {
 // the +1 is to ignore this (getCallerIgnoringLogMulti) frame
 return GetCaller(callDepth+1, "logrus/hooks.go", "logrus/entry.go", "logrus/logger.go", "logrus/exported.go", "asm_amd64.s")
}

package logS

import (
 "encoding/json"
 "errors"
 "fmt"
 "io/ioutil"
 "log"
 "os"
 "path/filepath"
 "strings"
 "sync"
 "time"
)

// RFC5424 log message levels.
const (
 LevelError = iota
 LevelWarn
 LevelInfo
 LevelDebug
)

// LoggerInterface Logger接口
type LoggerInterface interface {
 Init(config string) error
 WriteMsg(msg string, level int) error
 Destroy()
 Flush()
}

// LogWriter implements LoggerInterface.
// It writes messages by lines limit, file size limit, or time frequency.
type LogWriter struct {
 *log.Logger
 mw *MuxWriter
 // The opened file
 Filename string `json:"filename"`

 Maxlines     int `json:"maxlines"`
 maxlinesCurlines int

 // Rotate at size
 Maxsize    int `json:"maxsize"`
 maxsizeCursize int

 // Rotate daily
 Daily     bool `json:"daily"`
 Maxdays    int64 `json:"maxdays"`
 dailyOpendate int

 Rotate bool `json:"rotate"`

 startLock sync.Mutex // Only one log can write to the file

 Level int `json:"level"`
}

// MuxWriter an *os.File writer with locker.
type MuxWriter struct {
 sync.Mutex
 fd *os.File
}

// write to os.File.
func (l *MuxWriter) Write(b []byte) (int, error) {
 l.Lock()
 defer l.Unlock()
 return l.fd.Write(b)
}

// SetFd set os.File in writer.
func (l *MuxWriter) SetFd(fd *os.File) {
 if l.fd != nil {
 _ = l.fd.Close()
 }
 l.fd = fd
}

// NewFileWriter create a FileLogWriter returning as LoggerInterface.
func NewFileWriter() LoggerInterface {
 w := &LogWriter{
 Filename: "",
 Maxlines: 1000000,
 Maxsize: 1 << 28, //256 MB
 Daily:  true,
 Maxdays: 7,
 Rotate:  true,
 Level:  LevelDebug,
 }
 // use MuxWriter instead direct use os.File for lock write when rotate
 w.mw = new(MuxWriter)
 // set MuxWriter as Logger's io.Writer
 w.Logger = log.New(w.mw, "", log.Ldate|log.Ltime)
 return w
}

// Init file logger with json config.
// jsonconfig like:
// {
// "filename":"logs/sample.log",
// "maxlines":10000,
// "maxsize":1<<30,
// "daily":true,
// "maxdays":15,
// "rotate":true
// }
func (w *LogWriter) Init(jsonconfig string) error {
 err := json.Unmarshal([]byte(jsonconfig), w)
 if err != nil {
 return err
 }
 if len(w.Filename) == 0 {
 return errors.New("jsonconfig must have filename")
 }
 err = w.startLogger()
 return err
}

// start file logger. create log file and set to locker-inside file writer.
func (w *LogWriter) startLogger() error {
 fd, err := w.createLogFile()
 if err != nil {
 return err
 }
 w.mw.SetFd(fd)
 err = w.initFd()
 if err != nil {
 return err
 }
 return nil
}

func (w *LogWriter) docheck(size int) {
 w.startLock.Lock()
 defer w.startLock.Unlock()
 if w.Rotate && ((w.Maxlines > 0 && w.maxlinesCurlines >= w.Maxlines) ||
 (w.Maxsize > 0 && w.maxsizeCursize >= w.Maxsize) ||
 (w.Daily && time.Now().Day() != w.dailyOpendate)) {
 if err := w.DoRotate(); err != nil {
  fmt.Fprintf(os.Stderr, "FileLogWriter(%q): %s\n", w.Filename, err)
  return
 }
 }
 w.maxlinesCurlines++
 w.maxsizeCursize += size
}

// WriteMsg write logger message into file.
func (w *LogWriter) WriteMsg(msg string, level int) error {
 if level > w.Level {
 return nil
 }
 n := 24 + len(msg) // 24 stand for the length "2013/06/23 21:00:22 [T] "
 w.docheck(n)
 w.Logger.Print(msg)
 return nil
}

func (w *LogWriter) createLogFile() (*os.File, error) {
 // Open the log file
 fd, err := os.OpenFile(w.Filename, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0660)
 return fd, err
}

func (w *LogWriter) initFd() error {
 fd := w.mw.fd
 finfo, err := fd.Stat()
 if err != nil {
 return fmt.Errorf("get stat err: %s", err)
 }
 w.maxsizeCursize = int(finfo.Size())
 w.dailyOpendate = time.Now().Day()
 if finfo.Size() > 0 {
 content, err := ioutil.ReadFile(w.Filename)
 if err != nil {
  return err
 }
 w.maxlinesCurlines = len(strings.Split(string(content), "\n"))
 } else {
 w.maxlinesCurlines = 0
 }
 return nil
}

// DoRotate means it need to write file in new file.
// new file name like xx.log.2013-01-01.2
func (w *LogWriter) DoRotate() error {
 _, err := os.Lstat(w.Filename)
 if err == nil { // file exists
 // Find the next available number
 num := 1
 fname := ""
 for ; err == nil && num <= 999; num++ {
  fname = w.Filename + fmt.Sprintf(".%s.%03d", time.Now().Format("2006-01-02"), num)
  _, err = os.Lstat(fname)
 }
 // return error if the last file checked still existed
 if err == nil {
  return fmt.Errorf("Rotate: Cannot find free log number to rename %s", w.Filename)
 }

 // block Logger's io.Writer
 w.mw.Lock()
 defer w.mw.Unlock()

 fd := w.mw.fd
 _ = fd.Close()

 // close fd before rename
 // Rename the file to its newfound home
 err = os.Rename(w.Filename, fname)
 if err != nil {
  return fmt.Errorf("Rotate: %s", err)
 }

 // re-start logger
 err = w.startLogger()
 if err != nil {
  return fmt.Errorf("Rotate StartLogger: %s", err)
 }

 go w.deleteOldLog()
 }

 return nil
}

func (w *LogWriter) deleteOldLog() {
 dir := filepath.Dir(w.Filename)
 _ = filepath.Walk(dir, func(path string, info os.FileInfo, err error) (returnErr error) {
 defer func() {
  if r := recover(); r != nil {
  returnErr = fmt.Errorf("Unable to delete old log '%s', error: %+v", path, r)
  fmt.Println(returnErr)
  }
 }()

 if !info.IsDir() && info.ModTime().Unix() < (time.Now().Unix()-60*60*24*w.Maxdays) {
  if strings.HasPrefix(filepath.Base(path), filepath.Base(w.Filename)) {
  _ = os.Remove(path)
  }
 }
 return
 })
}

// Destroy destroy file logger, close file writer.
func (w *LogWriter) Destroy() {
 _ = w.mw.fd.Close()
}

// Flush file logger.
// there are no buffering messages in file logger in memory.
// flush file means sync file from disk.
func (w *LogWriter) Flush() {
 _ = w.mw.fd.Sync()
}

package logrus

// A hook to be fired when logging on the logging levels returned from
// `Levels()` on your implementation of the interface. Note that this is not
// fired in a goroutine or a channel with workers, you should handle such
// functionality yourself if your call is non-blocking and you don't wish for
// the logging calls for levels returned from `Levels()` to block.
type Hook interface {
 Levels() []Level
 Fire(*Entry) error
}

// Internal type for storing the hooks on a logger instance.
type LevelHooks map[Level][]Hook

// Add a hook to an instance of logger. This is called with
// `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.
func (hooks LevelHooks) Add(hook Hook) {
 for _, level := range hook.Levels() {
 hooks[level] = append(hooks[level], hook)
 }
}

// Fire all the hooks for the passed level. Used by `entry.log` to fire
// appropriate hooks for a log entry.
func (hooks LevelHooks) Fire(level Level, entry *Entry) error {
 for _, hook := range hooks[level] {
 if err := hook.Fire(entry); err != nil {
  return err
 }
 }
 return nil
}

type Hook interface {
 Levels() []Level
 Fire(*Entry) error
}

// log_hook.go
package logger

import (
 "fmt"
 "github.com/sirupsen/logrus"
 "library/util/constant"
 "os"
)

//自实现 logrus hook
func getLogger(module string) *logrus.Logger {
 //实例化
 logger := logrus.New()
 //设置输出
 logger.Out = os.Stdout
 //设置日志级别
 logger.SetLevel(logrus.DebugLevel)
 //设置日志格式
 //自定writer就行， hook 交给 lfshook
 logger.AddHook(newLogrusHook(constant.GetLogPath(), module))
 
 logger.SetFormatter(&logrus.JSONFormatter{
 TimestampFormat:"2006-01-02 15:04:05",
 })
 return logger
}

//确保每次调用使用的文件都是唯一的。
func GetNewFieldLoggerContext(module,appField string) *logrus.Entry {
 logger:= getLogger(module)
 return logger.WithFields(logrus.Fields{
 "app": appField,
 })
}

//订阅 警告日志
func SubscribeLog(entry *logrus.Entry, subMap SubscribeMap) {
 logger := entry.Logger
 logger.AddHook(newSubScribeHook(subMap))
 fmt.Println("日志订阅成功")
}

// writer.go
package logger

import (
 "fmt"
 "github.com/pkg/errors"
 "io"
 "library/util"
 "os"
 "path/filepath"
 "sync"
 "time"
)

type LogWriter struct {
 logDir       string //日志根目录地址。
 module       string //模块 名
  curFileName   string //当前被指定的filename
 curBaseFileName   string //在使用中的file
 turnCateDuration  time.Duration
 mutex      sync.RWMutex
 outFh      *os.File
}

func (w *LogWriter) Write(p []byte) (n int, err error) {
 w.mutex.Lock()
 defer w.mutex.Unlock()
 if out, err:= w.getWriter(); err!=nil {
 return 0, errors.New("failed to fetch target io.Writer")
 }else{
 return out.Write(p)
 }
}

func (w *LogWriter) getFileName() string {
 base := time.Now().Truncate(w.turnCateDuration)
 return fmt.Sprintf("%s/%s/%s_%s", w.logDir, base.Format("2006-01-02"), w.module, base.Format("15"))
}

func (w *LogWriter) getWriter()(io.Writer, error) {
 fileName := w.curBaseFileName
 //判断是否有新的文件名
 //会出现新的文件名
 baseFileName := w.getFileName()
 if baseFileName != fileName {
 fileName = baseFileName
 }

 dirname := filepath.Dir(fileName)
 if err := os.MkdirAll(dirname, 0755); err != nil {
 return nil, errors.Wrapf(err, "failed to create directory %s", dirname)
 }

 fileHandler, err := os.OpenFile(fileName, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
 if err != nil {
 return nil, errors.Errorf("failed to open file %s", err)
 }
 w.outFh.Close()
 w.outFh = fileHandler
 w.curBaseFileName = fileName
 w.curFileName = fileName

 return fileHandler, nil
}

func New(logPath, module string, duration time.Duration) *LogWriter {
 return &LogWriter{
 logDir: logPath,
 module: module,
 turnCateDuration:duration,
 curFileName: "",
 curBaseFileName: "",
 }
}

// hook.go
package logger

import (
 "github.com/rifflock/lfshook"
 "github.com/sirupsen/logrus"
 "time"
)
func newLogrusHook(logPath, moduel string) logrus.Hook {
 logrus.SetLevel(logrus.WarnLevel)

 writer := New(logPath, moduel, time.Hour * 2)

 lfsHook := lfshook.NewHook(lfshook.WriterMap{
 logrus.DebugLevel: writer,
 logrus.InfoLevel: writer,
 logrus.WarnLevel: writer,
 logrus.ErrorLevel: writer,
 logrus.FatalLevel: writer,
 logrus.PanicLevel: writer,
 }, &logrus.TextFormatter{DisableColors: true})

 // writer 生成新的log文件类型 writer 在通过new hook函数 消费 fire 函数
 // writer 是实现了writer 接口的库，在日志调用write是做预处理
 return lfsHook
}

func TestGetLogger(t *testing.T) {
 lg := GetNewFieldLoggerContext("test","d")
 lg.Logger.Info("????")
}

// subscribeHook.go
package logger

import (
 "fmt"
 "github.com/sirupsen/logrus"
 "library/email"
 "strings"
)

type SubscribeMap map[logrus.Level][]*email.Receiver
type SubscribeHook struct {
 subMap SubscribeMap
}
//此处可以自实现hook 目前使用三方hook
func(h *SubscribeHook)Levels() []logrus.Level{
 return logrus.AllLevels
}

func(h *SubscribeHook)Fire(entry *logrus.Entry) error{
 for level, receivers := range h.subMap {
 //命中 准备消费
 if level == entry.Level {
  if len(receivers) > 0 {
  email.SendEmail(receivers, fmt.Sprintf("%s:[系统日志警报]", entry.Level.String()),
   fmt.Sprintf("错误内容: %s",entry.Message))
  }
 }
 }
 return nil
}
func NewSubscribeMap(level logrus.Level, receiverStr string) SubscribeMap{
 subMap := SubscribeMap{}
 addressList := strings.Split(receiverStr,";")
 var receivers []*email.Receiver
 for _, address := range addressList {
 receivers = append(receivers, &email.Receiver{Email: address})
 }
 subMap[level] = receivers
 return subMap
}
func newSubScribeHook(subMap SubscribeMap) *SubscribeHook {
 return &SubscribeHook{subMap}

// email.go
package email

import (
 "fmt"
 "gopkg.in/gomail.v2"
 "regexp"
 "strconv"
)

type Sender struct {
 User   string
 Password string
 Host   string
 Port   int
 MailTo  []string
 Subject  string
 Content  string
}

type Receiver struct {
 Email  string
}

func (r *Receiver) Check() bool {
 pattern := `\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*` //匹配电子邮箱
 reg := regexp.MustCompile(pattern)
 return reg.MatchString(r.Email)
}

func (s *Sender) clean (){

}

//检查 邮箱正确性
func (s *Sender)NewReceiver(email string) *Receiver {
 rec := &Receiver{Email:email}
 if rec.Check() {
 m.MailTo = []string{email}
 return rec
 }else{
 fmt.Printf("email check fail 【%s】\n", email)
 return nil
 }
}
func (s *Sender)NewReceivers(receivers []*Receiver) {
 for _, rec := range receivers {
 if rec.Check() {
  m.MailTo = append(m.MailTo, rec.Email)
 }else{
  fmt.Printf("email check fail 【%s】\n", rec.Email)
 }
 }
}
// 163邮箱 password 为开启smtp后给的秘钥
var m = Sender{User:"6666666@163.com", Password:"666666666", Host: "smtp.163.com", Port: 465}

func SendEmail(receivers []*Receiver,subject, content string){
 m.NewReceivers(receivers)
 m.Subject = subject
 m.Content = content

 e := gomail.NewMessage()
 e.SetHeader("From", e.FormatAddress(m.User, "hengsheng"))
 e.SetHeader("To", m.MailTo...)  //发送给多个用户
 e.SetHeader("Subject", m.Subject) //设置邮件主题
 e.SetBody("text/html", m.Content)  //设置邮件正文
 d := gomail.NewDialer(m.Host, m.Port, m.User, m.Password)
 err := d.DialAndSend(e)
 if err != nil {
 fmt.Printf("error 邮件发送错误! %s \n", err.Error())
 }
}

o.logger = logger.GetNewFieldLoggerContext("test", "666")
if subscribeSocket {
 logger.SubscribeLog(o.Logger, logger.NewSubscribeMap(logrus.ErrorLevel, "a@163.com;b@163.com"))
 }
 // o 为实际结构体实例

// kafka hook
package logger

import (
 "github.com/sirupsen/logrus"
 "library/kafka"
 "library/util/constant"
)

type KafKaHook struct {
 kafkaProducer  *kafka.KafkaProducer
}


func(h *KafKaHook)Levels() []logrus.Level{
 return logrus.AllLevels
}

func(h *KafKaHook)Fire(entry *logrus.Entry) error{
 h.kafkaProducer.SendMsgSync(entry.Message)
 return nil
}

func newKafkaHook() *KafKaHook{
 producer := kafka.NewKafkaProducer(constant.KafkaLogElkTopic,true)
 return &KafKaHook{kafkaProducer: producer}
}

// kafkaProducer.go
package kafka

import (
 "errors"
 "fmt"
 "github.com/Shopify/sarama"
 "library/util/constant"
 "log"
 "time"
)

func GetKafkaAddress()[]string{
 return "127.0.0.1:9092"
}

//同步消息模式
func SyncProducer(topic, message string) error {
 config := sarama.NewConfig()
 config.Producer.Return.Successes = true
 config.Producer.Timeout = 5 * time.Second
 p, err := sarama.NewSyncProducer(GetKafkaAddress(), config)
 if err != nil {
 return errors.New(fmt.Sprintf("sarama.NewSyncProducer err, message=%s \n", err))
 }
 defer p.Close()
 msg := &sarama.ProducerMessage{
 Topic: topic,
 Value: sarama.ByteEncoder(message),
 }
 part, offset, err := p.SendMessage(msg)
 if err != nil {
 return errors.New(fmt.Sprintf("send sdsds err=%s \n", err))
 } else {
 fmt.Printf("发送成功，partition=%d, offset=%d \n", part, offset)
 return nil
 }
}

//async 异步生产者
type KafkaProducer struct {
 topic    string
 asyncProducer  *sarama.AsyncProducer
 syncProducer  *sarama.SyncProducer
 sync    bool
}

func NewKafkaProducer(topic string, sync bool) *KafkaProducer {
 k := &KafkaProducer{
 topic:   topic,
 sync:   sync,
 }
 if sync {
 k.initSync()
 }else{
 k.initAsync()
 }
 return k
}

func (k *KafkaProducer) initAsync() bool {
 if k.sync {
 fmt.Printf("sync producer cant call async func ！\n")
 return false
 }
 config := sarama.NewConfig()
 //等待服务器所有副本都保存成功后的响应
 config.Producer.RequiredAcks = sarama.WaitForAll
 //随机向partition发送消息
 config.Producer.Partitioner = sarama.NewRandomPartitioner
 //是否等待成功和失败后的响应,只有上面的RequireAcks设置不是NoReponse这里才有用.
 config.Producer.Return.Successes = true
 config.Producer.Return.Errors = true
 //设置使用的kafka版本,如果低于V0_10_0_0版本,消息中的timestrap没有作用.需要消费和生产同时配置
 //注意，版本设置不对的话，kafka会返回很奇怪的错误，并且无法成功发送消息
 config.Version = sarama.V0_10_0_1

 producer, e := sarama.NewAsyncProducer(GetKafkaAddress(), config)
 if e != nil {
 fmt.Println(e)
 return false
 }
 k.asyncProducer = &producer
 defer producer.AsyncClose()
 pd := *k.asyncProducer
 go func() {
 for{
  select {
  case <-pd.Successes():
  //fmt.Println("offset: ", suc.Offset, "timestamp: ", suc.Timestamp.String(), "partitions: ", suc.Partition)
  case fail := <-pd.Errors():
  fmt.Printf("err: %s \n", fail.Err.Error())
  }
 }
 }()

 return true
}

func (k *KafkaProducer) initSync() bool {
 if !k.sync {
 fmt.Println("async producer cant call sync func ！")
 return false
 }

 config := sarama.NewConfig()
 config.Producer.Return.Successes = true
 config.Producer.Timeout = 5 * time.Second
 p, err := sarama.NewSyncProducer(GetKafkaAddress(), config)
 k.syncProducer = &p
 if err != nil {
 log.Printf("sarama.NewSyncProducer err, message=%s \n", err)
 return false
 }
 return true
}

func (k *KafkaProducer) SendMsgAsync(sendStr string) {

 msg := &sarama.ProducerMessage{
 Topic: k.topic,
 }

 //将字符串转化为字节数组
 msg.Value = sarama.ByteEncoder(sendStr)
 //fmt.Println(value)

 //使用通道发送
 pd := *k.asyncProducer
 pd.Input() <- msg
}

func (k *KafkaProducer) SendMsgSync(sendStr string) bool {
 msg := &sarama.ProducerMessage{
 Topic: k.topic,
 Value: sarama.ByteEncoder(sendStr),
 }
 pd := *k.syncProducer
 part, offset, err := pd.SendMessage(msg)
 if err != nil {
 fmt.Printf("发送失败 send message(%s) err=%s \n", sendStr, err)
 return false
 } else {
 fmt.Printf("发送成功 partition=%d, offset=%d \n", part, offset)
 return true
 }
}

// kafkaConsumerGroup.go

package kafka

import (
 "context"
 "fmt"
 "github.com/Shopify/sarama"
 "log"
 "sync"
)

func NewKafkaConsumerGroup(topics []string, group string, businessCall func(message *sarama.ConsumerMessage) bool) *KafkaConsumerGroup {
 k := &KafkaConsumerGroup{
 brokers:  GetKafkaAddress(),
 topics:  topics,
 group:       group,
 channelBufferSize: 2,
 ready:       make(chan bool),
 version:  "1.1.1",
 handler:  businessCall,
 }
 k.Init()
 return k
}

// 消费者组(consumer group): 相同的group.id的消费者将视为同一个消费者组,
// 每个消费者都需要设置一个组id, 每条消息只能被 consumer group 中的一个
// Consumer 消费,但可以被多个 consumer group 消费
type KafkaConsumerGroup struct {
 //代理(broker): 一台kafka服务器称之为一个broker
 brokers   []string
 //主题(topic): 消息的一种逻辑分组，用于对消息分门别类，每一类消息称之为一个主题，相同主题的消息放在一个队列中
 topics    []string
 version   string
 ready       chan bool
 group       string
 channelBufferSize  int
 //业务调用
 handler     func(message *sarama.ConsumerMessage) bool
}

func (k *KafkaConsumerGroup)Init() func() {

 version,err := sarama.ParseKafkaVersion(k.version)
 if err!=nil{
 fmt.Printf("Error parsing Kafka version: %v", err)
 }
 cfg := sarama.NewConfig()
 cfg.Version = version
 // 分区分配策略
 cfg.Consumer.Group.Rebalance.Strategy = sarama.BalanceStrategyRange
 // 未找到组消费位移的时候从哪边开始消费
 cfg.Consumer.Offsets.Initial = -2
 // channel长度
 cfg.ChannelBufferSize = k.channelBufferSize
 ctx, cancel := context.WithCancel(context.Background())
 client, err := sarama.NewConsumerGroup(k.brokers, k.group, cfg)
 if err != nil {
  fmt.Printf("Error creating consumer group client: %v", err)
 }

 wg := &sync.WaitGroup{}
 wg.Add(1)
 go func() {
  defer func() {
  wg.Done()
  //util.HandlePanic("client.Consume panic", log.StandardLogger())
  }()
  for {
  if err := client.Consume(ctx, k.topics, k); err != nil {
   log.Printf("Error from consumer: %v", err)
  }
  // check if context was cancelled, signaling that the consumer should stop
  if ctx.Err() != nil {
   log.Println(ctx.Err())
   return
  }
  k.ready = make(chan bool)
  }
 }()

 <-k.ready
 fmt.Printf("Sarama consumer up and running!... \n")
 // 保证在系统退出时，通道里面的消息被消费
 return func() {
  cancel()
  wg.Wait()
  if err = client.Close(); err != nil {
  fmt.Printf("Error closing client: %v \n", err)
  }
 }

}

// Setup is run at the beginning of a new session, before ConsumeClaim
func (k *KafkaConsumerGroup) Setup(sarama.ConsumerGroupSession) error {
 // Mark the consumer as ready
 close(k.ready)
 return nil
}

// Cleanup is run at the end of a session, once all ConsumeClaim goroutines have exited
func (k *KafkaConsumerGroup) Cleanup(sarama.ConsumerGroupSession) error {
 return nil
}

// ConsumeClaim must start a consumer loop of ConsumerGroupClaim's Messages().
func (k *KafkaConsumerGroup) ConsumeClaim(session sarama.ConsumerGroupSession, claim sarama.ConsumerGroupClaim) error {

 // NOTE:
 // Do not move the code below to a goroutine.
 // The `ConsumeClaim` itself is called within a goroutine, see:
 // https://github.com/Shopify/sarama/blob/master/consumer_group.go#L27-L29
 // 具体消费消息
 for message := range claim.Messages() {
 //msg := string(message.Value)
 //k.logger.Infof("卡夫卡: %s", msg)

 if ok:= k.handler(message); ok {
  // 更新位移
  session.MarkMessage(message, "")
 }
 //run.Run(msg)
 }
 return nil
}

func TestKafkaConsumerGroup_Init(t *testing.T) {
 //pd := NewKafkaProducer("test-fail",true)
 //pd.InitSync()
 k := NewKafkaConsumerGroup([]string{constant.KafkaALiSdkTopic}, "group-2", func(message *sarama.ConsumerMessage) bool {
 fmt.Println(string(message.Value))
 //如果失败的处理逻辑
 //if ok := pd.SendMsgSync("666666"); ok {
 // return true
 //}
 return false

 })
 consumerDone := k.Init()

 sigterm := make(chan os.Signal, 1)
 signal.Notify(sigterm, syscall.SIGINT, syscall.SIGTERM)
 select {
 case <-sigterm:
 fmt.Println("terminating: via signal")
 }
 consumerDone()
}