/// <summary>
/// Subscription data changed
/// </summary>
/// <param name="subscription"></param>
/// <param name="notification"></param>
/// <param name="stringTable"></param>
private void OnSubscriptionDataChanged(Subscription subscription,
DataChangeNotification notification, IList <string> stringTable)
{
try {
if (OnSubscriptionChange == null)
{
return;
}
var message = new SubscriptionNotificationModel {
ServiceMessageContext = subscription.Session.MessageContext,
ApplicationUri = subscription.Session.Endpoint.Server.ApplicationUri,
EndpointUrl = subscription.Session.Endpoint.EndpointUrl,
SubscriptionId = Id,
Notifications = notification
.ToMonitoredItemNotifications(subscription.MonitoredItems)
.ToList()
};
OnSubscriptionChange?.Invoke(this, message);
}
catch (Exception ex) {
_logger.Debug(ex, "Exception processing subscription notification");
}
}
/// <summary>
/// Subscription data changed
/// </summary>
/// <param name="subscription"></param>
/// <param name="notification"></param>
/// <param name="stringTable"></param>
private void OnSubscriptionDataChanged(Subscription subscription,
DataChangeNotification notification, IList <string> stringTable)
{
try {
if (OnSubscriptionChange == null)
{
return;
}
if (notification == null)
{
_logger.Warning("DataChange for subscription: {Subscription} having empty notification",
subscription.DisplayName);
return;
}
if (_currentlyMonitored == null)
{
_logger.Information("DataChange for subscription: {Subscription} having no monitored items yet",
subscription.DisplayName);
return;
}
// check if notification is a keep alive
var isKeepAlive = notification?.MonitoredItems?.Count == 1 &&
notification?.MonitoredItems?.First().ClientHandle == 0 &&
notification?.MonitoredItems?.First().Message?.NotificationData?.Count == 0;
var sequenceNumber = notification?.MonitoredItems?.First().Message?.SequenceNumber;
var publishTime = (notification?.MonitoredItems?.First().Message?.PublishTime).
GetValueOrDefault(DateTime.MinValue);
_logger.Debug("DataChange for subscription: {Subscription}, sequence#: " +
"{Sequence} isKeepAlive{KeepAlive}, publishTime: {PublishTime}",
subscription.DisplayName, sequenceNumber, isKeepAlive, publishTime);
var message = new SubscriptionNotificationModel {
ServiceMessageContext = subscription.Session.MessageContext,
ApplicationUri = subscription.Session.Endpoint.Server.ApplicationUri,
EndpointUrl = subscription.Session.Endpoint.EndpointUrl,
SubscriptionId = Id,
Notifications = (!isKeepAlive)
? notification.ToMonitoredItemNotifications(
subscription.MonitoredItems).ToList()
: new List <MonitoredItemNotificationModel>()
};
message.IsKeyMessage = true;
// add the heartbeat for monitored items that did not receive a a datachange notification
// Try access lock if we cannot continue...
List <MonitoredItemWrapper> currentlyMonitored = null;
if (_lock.Wait(0))
{
try {
currentlyMonitored = _currentlyMonitored;
}
finally {
_lock.Release();
}
}
if (currentlyMonitored != null)
{
// add the heartbeat for monitored items that did not receive a
// a datachange notification
foreach (var item in currentlyMonitored)
{
if (isKeepAlive ||
!notification.MonitoredItems.Exists(m => m.ClientHandle == item.Item.ClientHandle))
{
if (item.TriggerHeartbeat(publishTime))
{
var heartbeatValue = item.Item.LastValue.ToMonitoredItemNotification(item.Item);
if (heartbeatValue != null)
{
heartbeatValue.SequenceNumber = sequenceNumber;
heartbeatValue.IsHeartbeat = true;
heartbeatValue.PublishTime = publishTime;
message.Notifications.Add(heartbeatValue);
}
}
else
{
// just reset the heartbeat for the items already processed
item.TriggerHeartbeat(publishTime);
}
}
}
}
OnSubscriptionChange?.Invoke(this, message);
}
catch (Exception ex) {
_logger.Debug(ex, "Exception processing subscription notification");
}
}