public Task StartAsync(CancellationToken cancellationToken)
{
try
{
_logger.LogInformation($"{_serviceName} is starting.");
_timer = new Timer(_ =>
{
using (LogHelper.AddRequestId())
{
try
{
using (var scope = _services.CreateScope())
{
_logger.LogInformation($"{_serviceName} start working.");
scope.ServiceProvider.GetService <T>().Action(cancellationToken).Wait(cancellationToken);
}
}
catch (Exception ex)
{
_logger.LogError(ex, $"Unhandled exception in {_serviceName} periodical work");
}
}
}, null, TimeSpan.Zero, _duration);
}
catch (Exception ex)
{
_logger.LogError($"Unhandled exception on initialization in {_serviceName}", ex);
}
return(Task.CompletedTask);
}
protected override async Task ExecuteAsync(CancellationToken cancellationToken)
{
_logger.LogInformation("Queued Hosted Service is starting.");
await new [] { TaskQueueLevel.Low, TaskQueueLevel.Medium, TaskQueueLevel.High }.AsyncForeach(async prior =>
{
_logger.LogInformation($"Queue #{prior} is starting");
while (!cancellationToken.IsCancellationRequested)
{
using (LogHelper.AddRequestId())
{
var(name, workItem) = await _taskManager.DequeueAsync(cancellationToken, prior);
_logger.LogDebug($"Queue #{prior}: Start processing work item {name}");
try
{
await workItem(cancellationToken);
}
catch (Exception ex)
{
_logger.LogError(ex,
$"Queue #{prior}: Error occurred executing {nameof(workItem)}.");
}
}
}
});
_logger.LogInformation("Queued Hosted Service is stopping.");
}
