php -ews-空的ItemId

Question

我正在为日历事件订阅EWS推送通知并记录通知。

我正在使用PHP-EWS：jamesiarmes / php-ews和Symfony 4.1

要订阅，我正在使用以下代码：

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    # ...
}

目前，我预订会议时会收到此通知：

    $eventTypes = new NonEmptyArrayOfNotificationEventTypesType();
    $eventTypes->EventType[] = NotificationEventTypeType::CREATED_EVENT;
    $eventTypes->EventType[] = NotificationEventTypeType::MODIFIED_EVENT;
    $eventTypes->EventType[] = NotificationEventTypeType::DELETED_EVENT;
    $eventTypes->EventType[] = NotificationEventTypeType::COPIED_EVENT;
    $eventTypes->EventType[] = NotificationEventTypeType::MOVED_EVENT;

    $folderIDs = new NonEmptyArrayOfBaseFolderIdsType();
    $folderIDs->DistinguishedFolderId = new DistinguishedFolderIdType();
    $folderIDs->DistinguishedFolderId->Id = DistinguishedFolderIdNameType::CALENDAR;

    $pushSubscription = new PushSubscriptionRequestType();
    $pushSubscription->FolderIds = $folderIDs;
    $pushSubscription->EventTypes = $eventTypes;
    $pushSubscription->StatusFrequency = $this->statusFrequency;
    $pushSubscription->URL = $this->subscriptionUrl;


    $subscribe_request = new SubscribeType();
    $subscribe_request->PushSubscriptionRequest = $pushSubscription;

我的问题是我没有收到“ ItemId”或“ ParentFolderId”。如何在通知中接收这些信息，或者如何获取已创建的会议？