log/slog Lshortfile replacement example.

slog_Lshortfile_example.go

package main

import (
    "os"
)

import (
    "io"
    "log/slog"
    "path/filepath"
)     

func makeLog(w io.Writer, level slog.Level) *slog.Logger {
    return slog.New(slog.NewTextHandler(w, &slog.HandlerOptions{
        AddSource: true,
        Level:     &level,
        ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
            if a.Key == slog.SourceKey {
                source, _ := a.Value.Any().(*slog.Source)
                if source != nil {
                    source.File = filepath.Base(source.File)
                }   
            }   
            return a
        },  
    })) 
}   

func main() {
    logger := makeLog(os.Stderr, slog.LevelInfo)
    logger.Info("Hello World!")
}