internal void OnDeserializedMethod(StreamingContext context)
{
if (MonitoredItems.Count == 0)
{
throw new Exception("Configuration did not specify monitored items!");
}
if (ServerUrl == null)
{
throw new Exception("Configuration did not contain an endpoint Uri");
}
if (string.IsNullOrEmpty(Id))
{
throw new Exception("Configuration did not contain a device name!");
}
MonitoredItems.ForEach(i => i.Notification += MonitoredItem_Notification);
}
/// <summary>
/// Creates a new set of monitored items for a set of variables.
/// </summary>
/// <remarks>
/// This method only handles data change subscriptions. Event subscriptions are created by the SDK.
/// </remarks>
protected override ServiceResult CreateMonitoredItem(ServerSystemContext context, NodeHandle handle, uint subscriptionId, double publishingInterval, DiagnosticsMasks diagnosticsMasks, TimestampsToReturn timestampsToReturn, MonitoredItemCreateRequest itemToCreate, ref long globalIdCounter, out MonitoringFilterResult filterResult, out IMonitoredItem monitoredItem)
{
filterResult = null;
monitoredItem = null;
// validate parameters.
MonitoringParameters parameters = itemToCreate.RequestedParameters;
// validate attribute.
if (!Attributes.IsValid(handle.Node.NodeClass, itemToCreate.ItemToMonitor.AttributeId))
{
return(StatusCodes.BadAttributeIdInvalid);
}
NodeState cachedNode = AddNodeToComponentCache(context, handle, handle.Node);
// check if the node is already being monitored.
MonitoredNode2 monitoredNode = null;
if (!MonitoredNodes.TryGetValue(handle.Node.NodeId, out monitoredNode))
{
MonitoredNodes[handle.Node.NodeId] = monitoredNode = new MonitoredNode2(this, cachedNode);
}
handle.Node = monitoredNode.Node;
handle.MonitoredNode = monitoredNode;
// create a globally unique identifier.
uint monitoredItemId = Utils.IncrementIdentifier(ref globalIdCounter);
// determine the sampling interval.
double samplingInterval = itemToCreate.RequestedParameters.SamplingInterval;
if (samplingInterval < 0)
{
samplingInterval = publishingInterval;
}
// ensure minimum sampling interval is not exceeded.
if (itemToCreate.ItemToMonitor.AttributeId == Attributes.Value)
{
BaseVariableState variable = handle.Node as BaseVariableState;
if (variable != null && samplingInterval < variable.MinimumSamplingInterval)
{
samplingInterval = variable.MinimumSamplingInterval;
}
}
// put a large upper limit on sampling.
if (samplingInterval == Double.MaxValue)
{
samplingInterval = 365 * 24 * 3600 * 1000.0;
}
// put an upper limit on queue size.
uint queueSize = itemToCreate.RequestedParameters.QueueSize;
if (queueSize > MaxQueueSize)
{
queueSize = MaxQueueSize;
}
// validate the monitoring filter.
Range euRange = null;
MonitoringFilter filterToUse = null;
ServiceResult error = ValidateMonitoringFilter(
context,
handle,
itemToCreate.ItemToMonitor.AttributeId,
samplingInterval,
queueSize,
parameters.Filter,
out filterToUse,
out euRange,
out filterResult);
if (ServiceResult.IsBad(error))
{
return(error);
}
// create the item.
MonitoredItem datachangeItem = new ComMonitoredItem(
Server,
this,
handle,
subscriptionId,
monitoredItemId,
context.OperationContext.Session,
itemToCreate.ItemToMonitor,
diagnosticsMasks,
timestampsToReturn,
itemToCreate.MonitoringMode,
itemToCreate.RequestedParameters.ClientHandle,
filterToUse,
filterToUse,
euRange,
samplingInterval,
queueSize,
itemToCreate.RequestedParameters.DiscardOldest,
0);
// report the initial value.
ReadInitialValue(context, handle, datachangeItem);
// update monitored item list.
monitoredItem = datachangeItem;
// save the monitored item.
MonitoredItems.Add(monitoredItemId, datachangeItem);
monitoredNode.Add(datachangeItem);
// report change.
OnMonitoredItemCreated(context, handle, datachangeItem);
return(error);
}
