/// <summary>
/// Sends the ResultsUpdated message if the number of rows has changed since last send.
/// </summary>
/// <param name="stateInfo"></param>
private async void SendResultAvailableOrUpdated(object stateInfo = null)
{
ResultSet currentResultSetSnapshot = (ResultSet)MemberwiseClone();
if (LastUpdatedSummary == null) // We need to send results available message.
{
// Fire off results Available task and await for it complete
//
await(ResultAvailable?.Invoke(currentResultSetSnapshot) ?? Task.CompletedTask);
ResultAvailable = null; // set this to null as we need to call ResultAvailable only once
}
else // We need to send results updated message.
{
// If there has been no change in rowCount since last update and we are not done yet then log and increase the timer duration
//
if (!currentResultSetSnapshot.hasCompletedRead && LastUpdatedSummary.RowCount == currentResultSetSnapshot.RowCount)
{
Logger.Write(TraceEventType.Warning, $"The result set:{Summary} has not made any progress in last {ResultTimerInterval} milliseconds and the read of resultset is not completed yet!");
ResultsIntervalMultiplier++;
}
// Fire off results updated task and await for it complete
//
await(ResultUpdated?.Invoke(currentResultSetSnapshot) ?? Task.CompletedTask);
}
// Update the LastUpdatedSummary to be the value captured in current snapshot
//
LastUpdatedSummary = currentResultSetSnapshot.Summary;
// Setup timer for the next callback
if (currentResultSetSnapshot.hasCompletedRead)
{
//If we have already completed reading then we are done and we do not need to send any more updates. Switch off timer.
//
resultsTimer.Change(Timeout.Infinite, Timeout.Infinite);
}
else
{
resultsTimer.Change(ResultTimerInterval, Timeout.Infinite);
}
}
private async Task SendCurrentResults()
{
try
{
// Wait to acquire the sendResultsSemphore before proceeding, as we want only one instance of this method executing at any given time.
//
sendResultsSemphore.Wait();
ResultSet currentResultSetSnapshot = (ResultSet)MemberwiseClone();
if (LastUpdatedSummary == null) // We need to send results available message.
{
// Fire off results Available task and await it
//
await(ResultAvailable?.Invoke(currentResultSetSnapshot) ?? Task.CompletedTask);
}
else if (LastUpdatedSummary.Complete) // If last result summary sent had already set the Complete flag
{
// We do not need to do anything except that make sure that RowCount has not update since last send.
Debug.Assert(LastUpdatedSummary.RowCount == currentResultSetSnapshot.RowCount,
$"Already reported rows should be equal to current RowCount, if had already sent completion flag as set in last message, countReported:{LastUpdatedSummary.RowCount}, current total row count: {currentResultSetSnapshot.RowCount}, row count override: {currentResultSetSnapshot.rowCountOverride}, this.rowCountOverride: {this.rowCountOverride} and this.RowCount: {this.RowCount}, LastUpdatedSummary: {LastUpdatedSummary}");
}
else // We need to send results updated message.
{
// Previously reported rows should be less than or equal to current number of rows about to be reported
//
Debug.Assert(LastUpdatedSummary.RowCount <= currentResultSetSnapshot.RowCount,
$"Already reported rows should less than or equal to current total RowCount, countReported:{LastUpdatedSummary.RowCount}, current total row count: {currentResultSetSnapshot.RowCount}, row count override: {currentResultSetSnapshot.rowCountOverride}, this.rowCountOverride: {this.rowCountOverride} and this.RowCount: {this.RowCount}, LastUpdatedSummary: {LastUpdatedSummary}");
// If there has been no change in rowCount since last update and we have not yet completed read then log and increase the timer duration
//
if (!currentResultSetSnapshot.hasCompletedRead &&
LastUpdatedSummary.RowCount == currentResultSetSnapshot.RowCount)
{
Logger.Write(TraceEventType.Warning,
$"The result set:{Summary} has not made any progress in last {ResultTimerInterval} milliseconds and the read of this result set is not yet complete!");
ResultsIntervalMultiplier++;
}
// Fire off results updated task and await it
//
await(ResultUpdated?.Invoke(currentResultSetSnapshot) ?? Task.CompletedTask);
}
// Update the LastUpdatedSummary to be the value captured in current snapshot
//
LastUpdatedSummary = currentResultSetSnapshot.Summary;
// Setup timer for the next callback
//
if (currentResultSetSnapshot.hasCompletedRead)
{
// If we have already completed reading then we are done and we do not need to send any more updates. Switch off timer.
//
resultsTimer.Change(Timeout.Infinite, Timeout.Infinite);
}
else
{
// If we have not yet completed reading then set the timer so this method gets called again after ResultTimerInterval milliseconds
//
resultsTimer.Change(ResultTimerInterval, Timeout.Infinite);
}
}
finally
{
// Release the sendResultsSemphore so the next invocation gets unblocked
//
sendResultsSemphore.Release();
}
}