public NotificationsController(ILogger logger, WebCourseManager courseManager, UlearnDb db, NotificationsRepo notificationsRepo, FeedRepo feedRepo, NotificationDataPreloader notificationDataPreloader) : base(logger, courseManager, db) { this.notificationsRepo = notificationsRepo ?? throw new ArgumentNullException(nameof(notificationsRepo)); this.feedRepo = feedRepo ?? throw new ArgumentNullException(nameof(feedRepo)); this.notificationDataPreloader = notificationDataPreloader; if (commentsFeedNotificationTransport == null) { commentsFeedNotificationTransport = feedRepo.GetCommentsFeedNotificationTransport(); } }