OverwriteResponseEvent for optionally modifying events before sending them to client.

add-event.go

@@ -86,7 +86,11 @@ func (rl *Relay) AddEvent(ctx context.Context, evt *nostr.Event) error {
 		}
 	}
 
+	for _, ovw := range rl.OverwriteResponseEvent {
+		ovw(ctx, evt)
+	}
 	notifyListeners(evt)
+
 	return nil
 }
 

handlers.go

@@ -236,6 +236,9 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 
 							go func(ch chan *nostr.Event) {
 								for event := range ch {
+									for _, ovw := range rl.OverwriteResponseEvent {
+										ovw(ctx, event)
+									}
 									ws.WriteJSON(nostr.EventEnvelope{SubscriptionID: &id, Event: *event})
 								}
 								eose.Done()

relay.go

@@ -45,6 +45,7 @@ type Relay struct {
 	RejectFilter             []func(ctx context.Context, filter nostr.Filter) (reject bool, msg string)
 	RejectCountFilter        []func(ctx context.Context, filter nostr.Filter) (reject bool, msg string)
 	OverwriteDeletionOutcome []func(ctx context.Context, target *nostr.Event, deletion *nostr.Event) (acceptDeletion bool, msg string)
+	OverwriteResponseEvent   []func(ctx context.Context, event *nostr.Event)
 	StoreEvent               []func(ctx context.Context, event *nostr.Event) error
 	DeleteEvent              []func(ctx context.Context, event *nostr.Event) error
 	QueryEvents              []func(ctx context.Context, filter nostr.Filter) (chan *nostr.Event, error)