static Task FireAndForgetJourneyWithLowMemoryStateDelegste(Func <TJourney, Task <TJourneyResult> > journeyTaker,
LambdaRequest <TJourney> command,
CloudWatchLogReporter <TJourney, TJourneyResult> cloudWatchLogReporter,
int journeyIndex,
CancellationToken token)
{
return(Task.Factory.StartNew(
iteration => InvokeJourney(
journeyTaker,
command.Journeys[(int)iteration % command.Journeys.Length],
cloudWatchLogReporter),
journeyIndex,
token).Unwrap());
}
static async Task InvokeJourney(Func <TJourney, Task <TJourneyResult> > journeyTaker,
TJourney journey,
CloudWatchLogReporter <TJourney, TJourneyResult> cloudWatchLogReporter)
{
var sw = Stopwatch.StartNew();
try
{
var result = await journeyTaker(journey);
sw.Stop();
cloudWatchLogReporter.ReportSuccess(journey, sw.Elapsed, result);
}
catch (Exception e)
{
cloudWatchLogReporter.ReportError(journey, sw.Elapsed, e);
}
}
public async Task Handle(SNSEvent snsEvent, ILambdaContext context)
{
var command = JsonConvert.DeserializeObject <LambdaRequest <TJourney> >(snsEvent.Records[0].Sns.Message);
var journeyReporter = new CloudWatchLogReporter <TJourney, TJourneyResult>(context.Logger);
var executionInterval = command.Duration / command.RequestCount;
var scheduler = new TaskSchedulingInterval();
var endOfStep = new CancellationTokenSource();
var endOfStepDuration = command.Duration + (command.Duration / 10);
endOfStep.CancelAfter(endOfStepDuration);
var endOfStepTask = Task.Delay(endOfStepDuration, endOfStep.Token);
try
{
var pendingTasks = new List <Task>();
for (var i = 0; i < command.RequestCount; i++)
{
scheduler.Start();
pendingTasks.Add(FireAndForgetJourneyWithLowMemoryStateDelegste(_journeyTaker, command, journeyReporter, i,
endOfStep.Token));
await scheduler.WaitFor(executionInterval, endOfStep.Token);
}
var firstTask = await Task.WhenAny(Task.WhenAll(pendingTasks), endOfStepTask);
journeyReporter.ReportFinished(firstTask == endOfStepTask ? CompletionState.Timeout : CompletionState.Success);
}
catch (Exception e)
{
journeyReporter.ReportFinished(CompletionState.Error, e);
}
}