[overlays] Add parameter to limit replay message age

Signed-off-by: Knut Ahlers <knut@ahlers.me>

internal/apimodules/overlays/default/eventclient.mjs

@@ -3,6 +3,7 @@
  * @typedef {Object} EventClient~Options
  * @prop {string} [channel] - Filter for specific channel events (format: `#channel`)
  * @prop {Object} handlers - Map event types to callback functions `(event, fields, time, live) => {...}`
+ * @prop {number} [maxReplayAge=-1] - Number of hours to replay the events for (-1 = infinite)
  * @prop {boolean} replay - Request a replay at connect (requires channel to be set to a channel name)
  * @prop {string} [token] - API access token to use to connect to the WebSocket
  */
@@ -63,7 +64,10 @@ export default class EventClient {
         // Auth was confirmed, request replay if wanted by client
         if (this.paramOptionFallback('replay', false) && this.paramOptionFallback('channel')) {
           this.socket.send(JSON.stringify({
-            fields: { channel: this.paramOptionFallback('channel') },
+            fields: {
+              channel: this.paramOptionFallback('channel'),
+              maxage: Number(this.paramOptionFallback('maxReplayAge', -1)),
+            },
             type: '_replay',
           }))
         }

internal/apimodules/overlays/overlays.go

@@ -49,6 +49,7 @@ var (
 
 	fsStack httpFSStack
 
+	ptrIntMinusOne = func(v int64) *int64 { return &v }(-1)
 	ptrStringEmpty = func(v string) *string { return &v }("")
 
 	store          plugins.StorageManager
@@ -246,7 +247,13 @@ func handleSocketSubscription(w http.ResponseWriter, r *http.Request) {
 
 			case msgTypeRequestReplay:
 				go func() {
+					maxAge := time.Duration(recvMsg.Fields.MustInt64("maxage", ptrIntMinusOne)) * time.Hour
+					log.Errorf("DEBUG %s %T", maxAge, recvMsg.Fields.Data()["maxage"])
 					for _, msg := range storedObject.GetChannelEvents(recvMsg.Fields.MustString("channel", ptrStringEmpty)) {
+						if maxAge > 0 && time.Since(msg.Time) > maxAge {
+							continue
+						}
+
 						sendMsgC <- msg
 					}
 				}()