log.SetReportCaller(true)

log.WithFields(log.Fields{"animal": "walrus"}).Info("A walrus appears")

time="2020-03-29T15:58:09+08:00" level=info msg="A walrus appears" func=main.main file="F:/workspace/go/src/test/main.go:12" animal=walrus

func (s *LogFormatter) Format(entry *log.Entry) ([]byte, error) {
 timestamp := //日期格式实现
 entry.Caller //调用者信息
 entry.Data //withfiled方式传入的数据
 msg := 自己想要的格式输出内容
 return []byte(msg), nil
}
 
func main() {
 log.SetFormatter(new(LogFormatter)) //注册自定义格式
}

package gotools
 
import (
 "bytes"
 "errors"
 "fmt"
 "os"
 "path/filepath"
 "runtime"
 "strconv"
 "strings"
 "time"
 
 log "github.com/sirupsen/logrus"
)
 
//日志自定义格式
type LogFormatter struct{}
 
//格式详情
func (s *LogFormatter) Format(entry *log.Entry) ([]byte, error) {
 timestamp := time.Now().Local().Format("0102-150405.000")
 var file string
 var len int
 if entry.Caller != nil {
 file = filepath.Base(entry.Caller.File)
 len = entry.Caller.Line
 }
 //fmt.Println(entry.Data)
 msg := fmt.Sprintf("%s [%s:%d][GOID:%d][%s] %s\n", timestamp, file, len, getGID(), strings.ToUpper(entry.Level.String()), entry.Message)
 return []byte(msg), nil
}
 
func getGID() uint64 {
 b := make([]byte, 64)
 b = b[:runtime.Stack(b, false)]
 b = bytes.TrimPrefix(b, []byte("goroutine "))
 b = b[:bytes.IndexByte(b, ' ')]
 n, _ := strconv.ParseUint(string(b), 10, 64)
 return n
}
 
type logFileWriter struct {
 file *os.File
 logPath string
 fileDate string //判断日期切换目录
 appName string
 encoding string
}
 
func (p *logFileWriter) Write(data []byte) (n int, err error) {
 if p == nil {
 return 0, errors.New("logFileWriter is nil")
 }
 if p.file == nil {
 return 0, errors.New("file not opened")
 }
 
 //判断是否需要切换日期
 fileDate := time.Now().Format("20060102")
 if p.fileDate != fileDate {
 p.file.Close()
 err = os.MkdirAll(fmt.Sprintf("%s/%s", p.logPath, fileDate), os.ModePerm)
 if err != nil {
 return 0, err
 }
 filename := fmt.Sprintf("%s/%s/%s-%s.log", p.logPath, fileDate, p.appName, fileDate)
 
 p.file, err = os.OpenFile(filename, os.O_WRONLY|os.O_APPEND|os.O_CREATE|os.O_SYNC, 0600)
 if err != nil {
 return 0, err
 }
 
 }
 if p.encoding != "" {
 dataToEncode := ConvertStringToByte(string(data), p.encoding)
 n, e := p.file.Write(dataToEncode)
 return n, e
 }
 
 n, e := p.file.Write(data)
 return n, e
 
}
 
//初始化日志
func InitLog(logPath string, appName string, encoding string) {
 fileDate := time.Now().Format("20060102")
 //创建目录
 err := os.MkdirAll(fmt.Sprintf("%s/%s", logPath, fileDate), os.ModePerm)
 if err != nil {
 log.Error(err)
 return
 }
 
 filename := fmt.Sprintf("%s/%s/%s-%s.log", logPath, fileDate, appName, fileDate)
 file, err := os.OpenFile(filename, os.O_WRONLY|os.O_APPEND|os.O_CREATE|os.O_SYNC, 0600)
 if err != nil {
 log.Error(err)
 return
 }
 
 fileWriter := logFileWriter{file, logPath, fileDate, appName, encoding}
 log.SetOutput(&fileWriter)
 
 log.SetReportCaller(true)
 log.SetFormatter(new(LogFormatter)) 
}

package main
 
import (
 log "github.com/sirupsen/logrus"
 "sand.com/gotools"
)
 
func main() {
 
 gotools.InitLog("./log/", "test", "gb18030")
 log.WithFields(log.Fields{"animal": "walrus"}).Info("A walrus appears")
 log.Info("测试中文")
}

func InitLog() {
 //设置输出样式，自带的只有两种样式logrus.JSONFormatter{}和logrus.TextFormatter{}
 log.SetFormatter(&log.TextFormatter{})
 log.SetOutput(os.Stdout)
 //设置output,默认为stderr,可以为任何io.Writer，比如文件*os.File
 file, err := os.OpenFile("checkemstools.log", os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
 writers := []io.Writer{
 file,
 os.Stdout}
 //同时写文件和屏幕
 fileAndStdoutWriter := io.MultiWriter(writers...)
 if err == nil {
 log.SetOutput(fileAndStdoutWriter)
 } else {
 log.Info("failed to log to file.")
 }
 //设置最低loglevel
 log.SetLevel(log.InfoLevel)
}