static void Main(string[] args)
{
var listener = new ObservableEventListener();
listener.EnableEvents(RxFloodQuickStartEventSource.Log, EventLevel.LogAlways, Keywords.All);
// ThrottleEventsWithEventId is a custom extension method that shows how you can leverage the power of Reactive Extensions (Rx)
// to perform filtering (or transformation) of the event stream before it is sent to the underlying sink.
// In this case, ThrottleEventsWithEventId will throttle entries with EventID=4 and mute additional occurrences for 15 seconds.
// This prevents a particular event from flooding the log sink, making it difficult to diagnose other issues.
// This can be useful in the case that a high-throughput event does not have a keyword or verbosity setting that makes it easy
// to exclude it in the call to listener.EnableEvents(EventSource, EventLevel, EventKeywords).
// Note: For basic scenarios without this extra filtering, you DO NOT need to use Rx, and SLAB does not depend on it.
var subscription = listener
.ThrottleEventsWithEventId(TimeSpan.FromSeconds(15), ThrottledEventId)
.LogToConsole(SingleLineFormatter);
// The previous custom extension method (ThrottleEventsWithEventId) is all that is needed to call to throttle
// an event that is flooding the log.
// The rest of the code in this QuickStart is here to show an interactive demo of how it looks if this filter is turned on or off.
bool currentlyThrottling = true;
var cts = new CancellationTokenSource();
Console.WriteLine("This program simulates the scenario of a particular event being logged multiple times in succession when a certain condition occurs,");
Console.WriteLine("such as when there is a transient or expected connectivity error during system upgrades.");
Console.WriteLine();
Console.WriteLine("While the application is logging messages, use the following commands:");
Console.WriteLine(" [ESC] Exists the application.");
Console.WriteLine(" [Spacebar] Toggles the throttling filter.");
Console.WriteLine();
Console.WriteLine();
Console.WriteLine("Press any key to start doing background work.");
var key = Console.ReadKey(false);
if (key.Key == ConsoleKey.Escape)
{
return;
}
DoBackgroundWork(cts.Token);
while (!cts.IsCancellationRequested)
{
key = Console.ReadKey(false);
switch (key.Key)
{
case ConsoleKey.Spacebar:
subscription.Dispose();
if (currentlyThrottling)
{
Console.WriteLine("Filter toggled: event entries will not be throttled. In this scenario, if there is no post-filtering of events, important messages could go unnoticed.");
Thread.Sleep(TimeSpan.FromSeconds(3));
currentlyThrottling = false;
// Note that the events are sent directly to the console, without using Reactive Extensions.
subscription = listener
.LogToConsole(SingleLineFormatter);
}
else
{
Console.WriteLine("Filter toggled: event entries with ID {0} will be throttled for 15 seconds to prevent that type of entry to flood the log.", ThrottledEventId);
Thread.Sleep(TimeSpan.FromSeconds(3));
currentlyThrottling = true;
// Note that the events are filtered first and then sent to the console, using Reactive Extensions.
subscription = listener
.ThrottleEventsWithEventId(TimeSpan.FromSeconds(15), ThrottledEventId)
.LogToConsole(SingleLineFormatter);
}
break;
case ConsoleKey.Escape:
cts.Cancel();
break;
}
}
listener.Dispose();
}