golang结构化日志log/slog包之LogValuer的用法简介

type LogValuer interface {
    LogValue() Value
}

package main
 
import (
    "log/slog"
    "os"
)
 
type Token string
 
// 实现 slog.LogValuer 接口
// 避免泄露 token
func (Token) LogValue() slog.Value {
    return slog.StringValue("******")
}
 
func main() {
    t := Token("shhhh!")
    logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
    logger.Info("生成 token", "用户", "路多辛的博客", "token", t)
}

package main
 
import (
    "log/slog"
)
 
type Name struct {
    First, Last string
}
 
func (n Name) LogValue() slog.Value {
    return slog.GroupValue(
        slog.String("first", n.First),
        slog.String("last", n.Last))
}
 
func main() {
    n := Name{"路多辛的博客", "路多辛的所思所想"}
    slog.Info("任务结束", "agent", n)
}

package main
 
import (
	"context"
	"fmt"
	"log/slog"
	"os"
	"path/filepath"
	"runtime"
	"time"
)
 
func Infof(logger *slog.Logger, format string, args ...any) {
	if !logger.Enabled(context.Background(), slog.LevelInfo) {
		return
	}
	var pcs [1]uintptr
	runtime.Callers(2, pcs[:]) // skip [Callers, Infof]
	r := slog.NewRecord(time.Now(), slog.LevelInfo, fmt.Sprintf(format, args...), pcs[0])
	_ = logger.Handler().Handle(context.Background(), r)
}
 
func main() {
	replace := func(groups []string, a slog.Attr) slog.Attr {
		// Remove time.
		if a.Key == slog.TimeKey && len(groups) == 0 {
			return slog.Attr{}
		}
		// Remove the directory from the source's filename.
		if a.Key == slog.SourceKey {
			source := a.Value.Any().(*slog.Source)
			source.File = filepath.Base(source.File)
		}
		return a
	}
	logger := slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{AddSource: true, ReplaceAttr: replace}))
	Infof(logger, "message, %s", "formatted")
}