queue: include send time in messages

cmd/kaiyan-ingest/main.go

@@ -125,11 +125,21 @@ func webhook(q *kgo.Client, secret []byte, errs chan<- error) http.HandlerFunc {
 				slog.String("broadcaster", ev.Event.Broadcaster),
 				slog.String("id", ev.Event.ID),
 			)
+			// Use the external clock for timestamps.
+			tm, err := time.Parse(time.RFC3339Nano, r.Header.Get("Twitch-Eventsub-Message-Timestamp"))
+			if err != nil {
+				log.LogAttrs(ctx, slog.LevelWarn, "bad timestamp",
+					slog.String("timestamp", r.Header.Get("Twitch-Eventsub-Message-Timestamp")),
+					slog.Any("err", err),
+				)
+				tm = time.Now()
+			}
 			msg := queue.Message{
-				ID:      ev.Event.ID,
-				Channel: ev.Event.Broadcaster,
-				Sender:  queue.Sender(secret, ev.Event.Broadcaster, ev.Event.Chatter),
-				Text:    ev.Event.Message.Text,
+				ID:        ev.Event.ID,
+				Channel:   ev.Event.Broadcaster,
+				Sender:    queue.Sender(secret, ev.Event.Broadcaster, ev.Event.Chatter),
+				Timestamp: tm.UnixNano(),
+				Text:      ev.Event.Message.Text,
 			}
 			// TODO(branden): the context in the http request cancels once this
 			// handler returns, which means the producer doesn't relay it.