handler_multi.go

package log

import (
	"context"
	"errors"
	"log/slog"
)

var _ slog.Handler = (*MultiHandler)(nil)

type MultiHandler struct {
	handlers []slog.Handler
}

func NewMultiHandler(handlers ...slog.Handler) slog.Handler {
	return &MultiHandler{
		handlers: handlers,
	}
}

func (h *MultiHandler) Enabled(ctx context.Context, l slog.Level) bool {
	for i := range h.handlers {
		if h.handlers[i].Enabled(ctx, l) {
			return true
		}
	}

	return false
}

func (h *MultiHandler) Handle(ctx context.Context, r slog.Record) error {
	var errs []error
	for i := range h.handlers {
		if h.handlers[i].Enabled(ctx, r.Level) {
			if err := h.handlers[i].Handle(ctx, r.Clone()); err != nil {
				errs = append(errs, err)
			}
		}
	}

	return errors.Join(errs...)
}

func (h *MultiHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
	handlers := make([]slog.Handler, len(h.handlers))
	for i, handler := range h.handlers {
		if handler == nil {
			continue
		}
		handlers[i] = handler.WithAttrs(attrs)
	}

	return NewMultiHandler(handlers...)
}

func (h *MultiHandler) WithGroup(name string) slog.Handler {
	if name == "" {
		return h
	}

	handlers := make([]slog.Handler, len(h.handlers))
	for i, handler := range h.handlers {
		if handler == nil {
			continue
		}
		handlers[i] = handler.WithGroup(name)
		if handlers[i] == nil {
			return nil
		}
	}

	return NewMultiHandler(handlers...)
}