Method Emit

modules/caddyevents/app.go:207–324

Emit creates and dispatches an event named eventName to all relevant handlers with the metadata data. Events are emitted and propagated synchronously. The returned Event value will have any additional information from the invoked handlers. Note that the data map is not copied, for efficiency. After

(ctx caddy.Context, eventName string, data map[string]any)

// Note that the data map is not copied, for efficiency. After Emit() is called, the
// data passed in should not be changed in other goroutines.
func (app *App) Emit(ctx caddy.Context, eventName string, data map[string]any) caddy.Event {
	logger := app.logger.With(zap.String("name", eventName))

	e, err := caddy.NewEvent(ctx, eventName, data)
	if err != nil {
		logger.Error("failed to create event", zap.Error(err))
	}

	var originModule caddy.ModuleInfo
	var originModuleID caddy.ModuleID
	var originModuleName string
	if origin := e.Origin(); origin != nil {
		originModule = origin.CaddyModule()
		originModuleID = originModule.ID
		originModuleName = originModule.String()
	}

	logger = logger.With(
		zap.String("id", e.ID().String()),
		zap.String("origin", originModuleName))

	// add event info to replacer, make sure it's in the context
	repl, ok := ctx.Context.Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
	if !ok {
		repl = caddy.NewReplacer()
		ctx.Context = context.WithValue(ctx.Context, caddy.ReplacerCtxKey, repl)
	}
	repl.Map(func(key string) (any, bool) {
		switch key {
		case "event":
			return e, true
		case "event.id":
			return e.ID(), true
		case "event.name":
			return e.Name(), true
		case "event.time":
			return e.Timestamp(), true
		case "event.time_unix":
			return e.Timestamp().UnixMilli(), true
		case "event.module":
			return originModuleID, true
		case "event.data":
			return e.Data, true
		}

		if after, ok0 := strings.CutPrefix(key, "event.data."); ok0 {
			key = after
			if val, ok := e.Data[key]; ok {
				return val, true
			}
		}

		return nil, false
	})

	logger = logger.WithLazy(zap.Any("data", e.Data))

	logger.Debug("event")