/// <summary>
/// Checks if the item meets the group's criteria.
/// </summary>
private bool MeetsGroupCriteria(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
// can only sample variables.
if ((monitoredItem.MonitoredItemType & MonitoredItemTypeMask.DataChange) == 0)
{
return(false);
}
// can't sample disabled items.
if (monitoredItem.MonitoringMode == MonitoringMode.Disabled)
{
return(false);
}
// check sampling interval.
if (AdjustSamplingInterval(monitoredItem.SamplingInterval) != m_samplingInterval)
{
return(false);
}
// compare session.
if (context.SessionId != m_session.Id)
{
return(false);
}
// check the diagnostics marks.
if (m_diagnosticsMask != (context.DiagnosticsMask & DiagnosticsMasks.OperationAll))
{
return(false);
}
return(true);
}
/// <summary>
/// Changes monitoring attributes the item.
/// </summary>
/// <remarks>
/// It will call the external source to change the monitoring if an external source was provided originally.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void ModifyMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
// find existing sampling group.
SamplingGroup samplingGroup = null;
if (m_sampledItems.TryGetValue(monitoredItem, out samplingGroup))
{
if (samplingGroup != null)
{
if (samplingGroup.ModifyMonitoring(context, monitoredItem))
{
return;
}
}
m_sampledItems.Remove(monitoredItem);
}
// assign to a new sampling group.
StartMonitoring(context, monitoredItem);
return;
}
}
/// <summary>
/// Starts monitoring the item.
/// </summary>
/// <remarks>
/// It will use the external source for monitoring if the source accepts the item.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void StartMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
// do nothing for disabled or exception based items.
if (monitoredItem.MonitoringMode == MonitoringMode.Disabled || monitoredItem.MinimumSamplingInterval == 0)
{
m_sampledItems.Add(monitoredItem, null);
return;
}
// find a suitable sampling group.
foreach (SamplingGroup samplingGroup in m_samplingGroups)
{
if (samplingGroup.StartMonitoring(context, monitoredItem))
{
m_sampledItems.Add(monitoredItem, samplingGroup);
return;
}
}
// create a new sampling group.
SamplingGroup samplingGroup2 = new SamplingGroup(
m_server,
m_nodeManager,
m_samplingRates,
context,
monitoredItem.SamplingInterval);
samplingGroup2.StartMonitoring(context, monitoredItem);
m_samplingGroups.Add(samplingGroup2);
m_sampledItems.Add(monitoredItem, samplingGroup2);
}
}
/// <summary>
/// Updates the group by apply any pending changes.
/// </summary>
/// <returns>
/// Returns true if the group has no more items and can be dropped.
/// </returns>
public bool ApplyChanges()
{
lock (m_lock)
{
// add items.
List <ISampledDataChangeMonitoredItem> itemsToSample = new List <ISampledDataChangeMonitoredItem>();
for (int ii = 0; ii < m_itemsToAdd.Count; ii++)
{
ISampledDataChangeMonitoredItem monitoredItem = m_itemsToAdd[ii];
if (!m_items.ContainsKey(monitoredItem.Id))
{
m_items.Add(monitoredItem.Id, monitoredItem);
if (monitoredItem.MonitoringMode != MonitoringMode.Disabled)
{
itemsToSample.Add(monitoredItem);
}
}
}
m_itemsToAdd.Clear();
// collect first sample.
if (itemsToSample.Count > 0)
{
Task.Run(() =>
{
DoSample(itemsToSample);
});
}
// remove items.
for (int ii = 0; ii < m_itemsToRemove.Count; ii++)
{
m_items.Remove(m_itemsToRemove[ii].Id);
}
m_itemsToRemove.Clear();
// start the group if it is not running.
if (m_items.Count > 0)
{
Startup();
}
// stop the group if it is running.
else if (m_items.Count == 0)
{
Shutdown();
}
// can be shutdown if no items left.
return(m_items.Count == 0);
}
}
/// <summary>
/// Stops monitoring the item.
/// </summary>
/// <returns>
/// Returns true if the items was marked for removal from the group.
/// </returns>
public bool StopMonitoring(ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock) {
if (m_items.ContainsKey(monitoredItem.Id))
{
m_itemsToRemove.Add(monitoredItem);
return(true);
}
return(false);
}
}
/// <summary>
/// Checks if the monitored item can be handled by the group.
/// </summary>
/// <returns>
/// True if the item was added to the group.
/// </returns>
/// <remarks>
/// The ApplyChanges() method must be called to actually start sampling the item.
/// </remarks>
public bool StartMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock) {
if (MeetsGroupCriteria(context, monitoredItem))
{
m_itemsToAdd.Add(monitoredItem);
monitoredItem.SetSamplingInterval(m_samplingInterval);
return(true);
}
return(false);
}
}
/// <summary>
/// Checks if the monitored item can still be handled by the group.
/// </summary>
/// <returns>
/// False if the item has be marked for removal from the group.
/// </returns>
/// <remarks>
/// The ApplyChanges() method must be called to actually stop sampling the item.
/// </remarks>
public bool ModifyMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock) {
if (m_items.ContainsKey(monitoredItem.Id))
{
if (MeetsGroupCriteria(context, monitoredItem))
{
monitoredItem.SetSamplingInterval(m_samplingInterval);
return(true);
}
m_itemsToRemove.Add(monitoredItem);
}
return(false);
}
}
/// <summary>
/// Stops monitoring the item.
/// </summary>
/// <remarks>
/// It will call the external source to stop the monitoring if an external source was provided originally.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void StopMonitoring(ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock) {
// check for sampling group.
SamplingGroup samplingGroup = null;
if (m_sampledItems.TryGetValue(monitoredItem, out samplingGroup))
{
if (samplingGroup != null)
{
samplingGroup.StopMonitoring(monitoredItem);
}
m_sampledItems.Remove(monitoredItem);
return;
}
}
}
/// <summary>
/// Periodically checks if the sessions have timed out.
/// </summary>
private void SampleMonitoredItems(object data)
{
try
{
//Utils.Trace("Server: {0} Thread Started.", Thread.CurrentThread.Name);
int sleepCycle = Convert.ToInt32(data, CultureInfo.InvariantCulture);
int timeToWait = sleepCycle;
while (m_server.IsRunning)
{
DateTime start = DateTime.UtcNow;
// wait till next sample.
if (m_shutdownEvent.WaitOne(timeToWait))
{
break;
}
// get current list of items to sample.
List <ISampledDataChangeMonitoredItem> items = new List <ISampledDataChangeMonitoredItem>();
lock (m_lock)
{
uint disabledItemCount = 0;
Dictionary <uint, ISampledDataChangeMonitoredItem> .Enumerator enumerator = m_items.GetEnumerator();
while (enumerator.MoveNext())
{
ISampledDataChangeMonitoredItem monitoredItem = enumerator.Current.Value;
if (monitoredItem.MonitoringMode == MonitoringMode.Disabled)
{
disabledItemCount++;
continue;
}
// check whether the item should be sampled.
//if (!monitoredItem.SamplingIntervalExpired())
//{
// continue;
//}
items.Add(monitoredItem);
}
}
// sample the values.
DoSample(items);
int delay = (int)(DateTime.UtcNow - start).TotalMilliseconds;
timeToWait = sleepCycle;
if (delay > sleepCycle)
{
timeToWait = 2 * sleepCycle - delay;
if (timeToWait < 0)
{
Utils.Trace("WARNING: SamplingGroup cannot sample fast enough. TimeToSample={0}ms, SamplingInterval={1}ms", delay, sleepCycle);
timeToWait = sleepCycle;
}
}
}
//Utils.Trace("Server: {0} Thread Exited Normally.", Thread.CurrentThread.Name);
}
catch (Exception e)
{
Utils.Trace(e, "Server: SampleMonitoredItems Thread Exited Unexpectedly.");
}
}
/// <summary>
/// Checks if the monitored item can be handled by the group.
/// </summary>
/// <returns>
/// True if the item was added to the group.
/// </returns>
/// <remarks>
/// The ApplyChanges() method must be called to actually start sampling the item.
/// </remarks>
public bool StartMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
if (MeetsGroupCriteria(context, monitoredItem))
{
m_itemsToAdd.Add(monitoredItem);
monitoredItem.SetSamplingInterval(m_samplingInterval);
return true;
}
return false;
}
}
/// <summary>
/// Checks if the monitored item can still be handled by the group.
/// </summary>
/// <returns>
/// False if the item has be marked for removal from the group.
/// </returns>
/// <remarks>
/// The ApplyChanges() method must be called to actually stop sampling the item.
/// </remarks>
public bool ModifyMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
if (m_items.ContainsKey(monitoredItem.Id))
{
if (MeetsGroupCriteria(context, monitoredItem))
{
monitoredItem.SetSamplingInterval(m_samplingInterval);
return true;
}
m_itemsToRemove.Add(monitoredItem);
}
return false;
}
}
/// <summary>
/// Stops monitoring the item.
/// </summary>
/// <remarks>
/// It will call the external source to stop the monitoring if an external source was provided originally.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void StopMonitoring(ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
// check for sampling group.
SamplingGroup samplingGroup = null;
if (m_sampledItems.TryGetValue(monitoredItem, out samplingGroup))
{
if (samplingGroup != null)
{
samplingGroup.StopMonitoring(monitoredItem);
}
m_sampledItems.Remove(monitoredItem);
return;
}
}
}
/// <summary>
/// Changes monitoring attributes the item.
/// </summary>
/// <remarks>
/// It will call the external source to change the monitoring if an external source was provided originally.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void ModifyMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
// find existing sampling group.
SamplingGroup samplingGroup = null;
if (m_sampledItems.TryGetValue(monitoredItem, out samplingGroup))
{
if (samplingGroup != null)
{
if (samplingGroup.ModifyMonitoring(context, monitoredItem))
{
return;
}
}
m_sampledItems.Remove(monitoredItem);
}
// assign to a new sampling group.
StartMonitoring(context, monitoredItem);
return;
}
}
/// <summary>
/// Starts monitoring the item.
/// </summary>
/// <remarks>
/// It will use the external source for monitoring if the source accepts the item.
/// The changes will not take affect until the ApplyChanges() method is called.
/// </remarks>
public virtual void StartMonitoring(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
// do nothing for disabled or exception based items.
if (monitoredItem.MonitoringMode == MonitoringMode.Disabled || monitoredItem.MinimumSamplingInterval == 0)
{
m_sampledItems.Add(monitoredItem, null);
return;
}
// find a suitable sampling group.
foreach (SamplingGroup samplingGroup in m_samplingGroups)
{
if (samplingGroup.StartMonitoring(context, monitoredItem))
{
m_sampledItems.Add(monitoredItem, samplingGroup);
return;
}
}
// create a new sampling group.
SamplingGroup samplingGroup2 = new SamplingGroup(
m_server,
m_nodeManager,
m_samplingRates,
context,
monitoredItem.SamplingInterval);
samplingGroup2.StartMonitoring(context, monitoredItem);
m_samplingGroups.Add(samplingGroup2);
m_sampledItems.Add(monitoredItem, samplingGroup2);
}
}
/// <summary>
/// Modifies a monitored item and calls ModifyMonitoring().
/// </summary>
public virtual ServiceResult ModifyMonitoredItem(
OperationContext context,
TimestampsToReturn timestampsToReturn,
ISampledDataChangeMonitoredItem monitoredItem,
MonitoredItemModifyRequest itemToModify,
Range range)
{
// use existing interval as sampling interval.
double samplingInterval = itemToModify.RequestedParameters.SamplingInterval;
if (samplingInterval < 0)
{
samplingInterval = monitoredItem.SamplingInterval;
}
// limit the sampling interval.
double minimumSamplingInterval = monitoredItem.MinimumSamplingInterval;
if (minimumSamplingInterval > 0 && samplingInterval < minimumSamplingInterval)
{
samplingInterval = minimumSamplingInterval;
}
// calculate queue size.
uint queueSize = itemToModify.RequestedParameters.QueueSize;
if (queueSize == 0)
{
queueSize = monitoredItem.QueueSize;
}
if (queueSize > m_maxQueueSize)
{
queueSize = m_maxQueueSize;
}
// get filter.
MonitoringFilter filter = null;
if (!ExtensionObject.IsNull(itemToModify.RequestedParameters.Filter))
{
filter = (MonitoringFilter)itemToModify.RequestedParameters.Filter.Body;
}
// update limits for event filters.
if (filter is EventFilter)
{
samplingInterval = 0;
}
// modify the item attributes.
ServiceResult error = monitoredItem.ModifyAttributes(
context.DiagnosticsMask,
timestampsToReturn,
itemToModify.RequestedParameters.ClientHandle,
filter,
filter,
range,
samplingInterval,
queueSize,
itemToModify.RequestedParameters.DiscardOldest);
// state of item did not change if an error returned here.
if (ServiceResult.IsBad(error))
{
return error;
}
// update sampling.
ModifyMonitoring(context, monitoredItem);
// everything is ok.
return ServiceResult.Good;
}
/// <summary>
/// Stops monitoring the item.
/// </summary>
/// <returns>
/// Returns true if the items was marked for removal from the group.
/// </returns>
public bool StopMonitoring(ISampledDataChangeMonitoredItem monitoredItem)
{
lock (m_lock)
{
if (m_items.ContainsKey(monitoredItem.Id))
{
m_itemsToRemove.Add(monitoredItem);
return true;
}
return false;
}
}
/// <summary>
/// Modifies a monitored item and calls ModifyMonitoring().
/// </summary>
public virtual ServiceResult ModifyMonitoredItem(
OperationContext context,
TimestampsToReturn timestampsToReturn,
ISampledDataChangeMonitoredItem monitoredItem,
MonitoredItemModifyRequest itemToModify,
Range range)
{
// use existing interval as sampling interval.
double samplingInterval = itemToModify.RequestedParameters.SamplingInterval;
if (samplingInterval < 0)
{
samplingInterval = monitoredItem.SamplingInterval;
}
// limit the sampling interval.
double minimumSamplingInterval = monitoredItem.MinimumSamplingInterval;
if (minimumSamplingInterval > 0 && samplingInterval < minimumSamplingInterval)
{
samplingInterval = minimumSamplingInterval;
}
// calculate queue size.
uint queueSize = itemToModify.RequestedParameters.QueueSize;
if (queueSize == 0)
{
queueSize = monitoredItem.QueueSize;
}
if (queueSize > m_maxQueueSize)
{
queueSize = m_maxQueueSize;
}
// get filter.
MonitoringFilter filter = null;
if (!ExtensionObject.IsNull(itemToModify.RequestedParameters.Filter))
{
filter = (MonitoringFilter)itemToModify.RequestedParameters.Filter.Body;
}
// update limits for event filters.
if (filter is EventFilter)
{
samplingInterval = 0;
}
// modify the item attributes.
ServiceResult error = monitoredItem.ModifyAttributes(
context.DiagnosticsMask,
timestampsToReturn,
itemToModify.RequestedParameters.ClientHandle,
filter,
filter,
range,
samplingInterval,
queueSize,
itemToModify.RequestedParameters.DiscardOldest);
// state of item did not change if an error returned here.
if (ServiceResult.IsBad(error))
{
return(error);
}
// update sampling.
ModifyMonitoring(context, monitoredItem);
// everything is ok.
return(ServiceResult.Good);
}
/// <summary>
/// Checks if the item meets the group's criteria.
/// </summary>
private bool MeetsGroupCriteria(OperationContext context, ISampledDataChangeMonitoredItem monitoredItem)
{
// can only sample variables.
if ((monitoredItem.MonitoredItemType & MonitoredItemTypeMask.DataChange) == 0)
{
return false;
}
// can't sample disabled items.
if (monitoredItem.MonitoringMode == MonitoringMode.Disabled)
{
return false;
}
// check sampling interval.
if (AdjustSamplingInterval(monitoredItem.SamplingInterval) != m_samplingInterval)
{
return false;
}
// compare session.
if (context.SessionId != m_session.Id)
{
return false;
}
// check the diagnostics marks.
if (m_diagnosticsMask != (context.DiagnosticsMask & DiagnosticsMasks.OperationAll))
{
return false;
}
return true;
}
