type Option struct {
    // log level (default: debug)
    Level slog.Leveler

    // optional: zerolog logger (default: zerolog.Logger)
    Logger *zerolog.Logger
    // optional: don't add timestamp to record
    NoTimestamp bool

    // optional: customize json payload builder
    Converter Converter
    // optional: fetch attributes from context
    AttrFromContext []func(ctx context.Context) []slog.Attr

    // optional: see slog.HandlerOptions
    AddSource   bool
    ReplaceAttr func(groups []string, a slog.Attr) slog.Attr
}

slogzerolog.SourceKey = "source"
slogzerolog.ErrorKeys = []string{"error", "err"}
slogzerolog.LogLevels = map[slog.Level]zerolog.Level{...}

import (
    "github.com/rs/zerolog"
    slogzerolog "github.com/samber/slog-zerolog/v2"
    "os"
    "log/slog"
)

func main() {
    zerologLogger := zerolog.New(zerolog.ConsoleWriter{Out: os.Stderr})

    logger := slog.New(slogzerolog.Option{Level: slog.LevelDebug, Logger: &zerologLogger}.NewZerologHandler())
    logger = logger.
        With("environment", "dev").
        With("release", "v1.0.0")

    // log error
    logger.
        With("category", "sql").
        With("query.statement", "SELECT COUNT(*) FROM users;").
        With("query.duration", 1*time.Second).
        With("error", fmt.Errorf("could not count users")).
        Error("caramba!")

    // log user signup
    logger.
        With(
            slog.Group("user",
                slog.String("id", "user-123"),
                slog.Time("created_at", time.Now()),
            ),
        ).
        Info("user registration")
}

import (
	slogzerolog "github.com/samber/slog-zerolog"
	slogotel "github.com/samber/slog-otel"
	"go.opentelemetry.io/otel/sdk/trace"
)

func main() {
	tp := trace.NewTracerProvider(
		trace.WithSampler(trace.AlwaysSample()),
	)
	tracer := tp.Tracer("hello/world")

	ctx, span := tracer.Start(context.Background(), "foo")
	defer span.End()

	span.AddEvent("bar")

	logger := slog.New(
		slogzerolog.Option{
			// ...
			AttrFromContext: []func(ctx context.Context) []slog.Attr{
				slogotel.ExtractOtelAttrFromContext([]string{"tracing"}, "trace_id", "span_id"),
			},
		}.NewZerologHandler(),
	)

	logger.ErrorContext(ctx, "a message")
}