private void HandleNewMeasurementsRequest(MeasurementKey[] Keys)
{
OnStatusMessage("Received request for {0} keys...", new object[] { Keys.Count() });
if (!IsConnected)
AttemptConnection();
var query = from row in DataSource.Tables["ActiveMeasurements"].AsEnumerable()
from key in Keys
where row["ID"].ToString().Split(':')[1] == key.ID.ToString()
select new { Key = key, AlternateTag = row["ALTERNATETAG"].ToString(), PointTag = row["POINTTAG"].ToString() };
StringBuilder tagFilter = new StringBuilder();
foreach (var row in query)
{
string tagname = row.PointTag;
if (!String.IsNullOrWhiteSpace(row.AlternateTag))
tagname = row.AlternateTag;
if (!m_tagKeyMap.ContainsKey(tagname))
{
m_tagKeyMap.AddOrUpdate(tagname, row.Key, (k, v) => row.Key);
}
if (tagFilter.Length > 0)
tagFilter.Append(" OR ");
tagFilter.Append(string.Format("tag='{0}'", tagname));
}
m_points = m_server.GetPoints(tagFilter.ToString());
// event pipes are only applicable if enabled in connection string and this is a real time session, not playback
bool useEventPipes = m_useEventPipes && StartTimeConstraint == DateTime.MinValue && StopTimeConstraint == DateTime.MaxValue;
if (useEventPipes)
{
try
{
if (m_pipe != null)
((_DEventPipeEvents_Event)m_pipe).OnNewValue -= (PISDK._DEventPipeEvents_OnNewValueEventHandler)PipeOnOnNewValue;
m_pipe = m_points.Data.EventPipe;
((_DEventPipeEvents_Event)m_pipe).OnNewValue += (PISDK._DEventPipeEvents_OnNewValueEventHandler)PipeOnOnNewValue;
}
catch (ThreadAbortException) { throw; }
catch (Exception e)
{
useEventPipes = false; // try to run with polling instead of event pipes;
OnProcessException(e);
}
}
if (!useEventPipes)
{
// warn that we are going to use a different configuration here...
if (m_useEventPipes)
OnStatusMessage("WARNING: PI adapter switching from event pipes to polling due to error or start/stop time constraints.");
// set up a new thread to do some long calls to PI and set up threads, timers, etc for polling
StopGettingData();
ThreadPool.QueueUserWorkItem(StartGettingData, tagFilter);
}
m_useEventPipes = useEventPipes;
}
