public Task Handle(OrderReceivedEvent message) { if (message == null) { throw new ArgumentNullException(nameof(message)); } var notifier = _connectionManager.GetHubContext <SecuredHub>(); var lst = new[] { message.Client, message.Seller }; lst.Distinct(); var connectionIds = new List <string>(); foreach (var r in lst) { connectionIds.AddRange(SecuredHub.Connections.GetConnections(r).ToList()); } notifier.Clients.Clients(connectionIds).orderReceived(_responseBuilder.GetOrderReceivedEvent(message)); return(Task.FromResult(0)); }