Go logging for human

logger.go

package log

import (
	"bytes"
	"path"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/lestrrat/go-file-rotatelogs"
	"github.com/pkg/errors"
	"github.com/rifflock/lfshook"
	"github.com/sirupsen/logrus"
)

type bodyLogWriter struct {
	gin.ResponseWriter
	body *bytes.Buffer
}

func (w bodyLogWriter) Write(b []byte) (int, error) {
	w.body.Write(b)
	return w.ResponseWriter.Write(b)
}

type loggerEntryWithFields interface {
	WithFields(fields logrus.Fields) *logrus.Entry
}

// Log gin 访问日志
func Log(logger loggerEntryWithFields, timeFormat string, utc bool) gin.HandlerFunc {
	return func(c *gin.Context) {
		start := time.Now()
		blw := &bodyLogWriter{body: bytes.NewBufferString(""), ResponseWriter: c.Writer}
		c.Writer = blw
		c.Next()

		end := time.Now()
		latency := end.Sub(start)
		if utc {
			end = end.UTC()
		}

		entry := logger.WithFields(logrus.Fields{
			"referer":       c.Request.Referer(),
			"status":        c.Writer.Status(),
			"method":        c.Request.Method,
			"ip":            c.ClientIP(),
			"latency":       latency.Nanoseconds() / int64(time.Microsecond),
			"latency_human": latency.String(),
			"bytes_in":      c.Request.ContentLength,
			"bytes_out":     c.Writer.Size(),
			"response":      blw.body.String(),
			"request":       c.Request.RequestURI,
			"form":          c.Request.PostForm,
			"user-agent":    c.Request.UserAgent(),
			"time":          end.Format(timeFormat),
		})

		if len(c.Errors) > 0 {
			// Append error field if this is an erroneous request.
			entry.Error(c.Errors.String())
		} else {
			entry.Info()
		}
	}
}

// NewLogger 日志分割，绑定
func NewLogger(logPath, app string) *logrus.Logger {

	// 设置日志级别
	baseLogPath := path.Join(logPath, app+".log")
	writer, err := rotatelogs.New(
		baseLogPath+".%Y%m%d%H%M",
		rotatelogs.WithLinkName(baseLogPath),   // 生成软链，指向最新日志文件
		rotatelogs.WithMaxAge(7*24*time.Hour),  // 文件最大保存时间
		rotatelogs.WithRotationTime(time.Hour), // 日志切割时间间隔
	)
	if err != nil {
		logrus.Errorf("config local file system logger error. %v", errors.WithStack(err))
	}
	baseLogPath = path.Join(logPath, app+"_error.log")
	errWriter, err := rotatelogs.New(
		baseLogPath+".%Y%m%d%H%M",
		rotatelogs.WithLinkName(baseLogPath),   // 生成软链，指向最新日志文件
		rotatelogs.WithMaxAge(7*24*time.Hour),  // 文件最大保存时间
		rotatelogs.WithRotationTime(time.Hour), // 日志切割时间间隔
	)
	if err != nil {
		logrus.Errorf("config local file system logger error. %v", errors.WithStack(err))
	}

	log := logrus.New()

	customFormatter := new(logrus.JSONFormatter)
	customFormatter.TimestampFormat = "2006-01-02 15:04:05.999999"
	log.Formatter = customFormatter
	// 为不同级别设置不同的输出目的
	log.AddHook(lfshook.NewHook(
		lfshook.WriterMap{
			logrus.DebugLevel: writer,
			logrus.InfoLevel:  writer,
			logrus.WarnLevel:  errWriter,
			logrus.ErrorLevel: errWriter,
			logrus.FatalLevel: errWriter,
			logrus.PanicLevel: errWriter,
		},
		customFormatter,
	))
	return log
}