修改bug

mqtt_binding/request/request.go

@@ -39,11 +39,13 @@ func BindingJson[O any](c *mqtt_client.MqttClient, item *router.Item, request an
 		}
 	}
 
-	err := validate.Struct(request)
-	if err != nil {
-		var zero O
-		sendFunc(c, item, responseIdentifier, zero, err)
-		return false
+	if request != nil {
+		err := validate.Struct(request)
+		if err != nil {
+			var zero O
+			sendFunc(c, item, responseIdentifier, zero, err)
+			return false
+		}
 	}
 
 	return true