/// <summary>
/// Main
/// </summary>
public static async Task Main(string[] args)
{
// --> #1 AcquireLock with retry.
using (ILockObject outerLockObject = _lockFactory.AcquireLock(_lockKey, TimeSpan.FromSeconds(3)))
using (ILockObject innerLockObject = _lockFactory.AcquireLock(_lockKey, TimeSpan.FromSeconds(5), 2, TimeSpan.FromSeconds(2)))
Console.WriteLine($"Did I get a lock? -> {innerLockObject.IsAcquired}");
// --> #2 AcquireLockAsync with retry.
using (ILockObject outerLockObject = await _lockFactory.AcquireLockAsync(_lockKey, TimeSpan.FromSeconds(3)))
using (ILockObject innerLockObject = await _lockFactory.AcquireLockAsync(_lockKey, TimeSpan.FromSeconds(5), 2, TimeSpan.FromSeconds(2)))
Console.WriteLine($"Did I get a lock? -> {innerLockObject.IsAcquired}");
// --> #3 AcquireLockAsync with retry + timeout.
try
{
using (CancellationTokenSource ctSource = new CancellationTokenSource(TimeSpan.FromSeconds(3.5)))
{
using (ILockObject outerLockObject = await _lockFactory.AcquireLockAsync(_lockKey, TimeSpan.FromSeconds(3)))
using (ILockObject innerLockObject = await _lockFactory.AcquireLockAsync(_lockKey, TimeSpan.FromSeconds(5), 2, TimeSpan.FromSeconds(2), ctSource.Token))
Console.WriteLine($"Did I get a lock? -> {innerLockObject.IsAcquired}");
}
}
catch (OperationCanceledException)
{
Console.WriteLine("I expected for an OperationCanceledException.");
}
// --> #4 Dinner is ready to eat.
Parallel.For(0, 5, x => personEat(x));
Console.WriteLine("End of the dinner.");
}
public async Task <TResponse> ExecuteAsync <TResponse>(string key, Func <CancellationToken, Task <TResponse> > action)
{
ILockObject @lock = await _lockFactory.AcquireLockAsync(key);
DateTime processStarted = DateTime.UtcNow;
try
{
using var subscribedCancellationSource = new CancellationTokenSource();
await _redisSubscriber.SubscribeAsync(
key,
(channel, _) =>
{
_logger.LogInformation(
$"A cancellation message was received for key: {key}"
);
if (!subscribedCancellationSource.IsCancellationRequested)
{
subscribedCancellationSource.Cancel();
}
}
).ConfigureAwait(false);
TResponse response = await Policy
.Handle <Exception>()
.WaitAndRetryAsync(_distributedCancellationConfiguration.MaxRetries, _ => _distributedCancellationConfiguration.MaximumRetryDelay)
.ExecuteAsync(() =>
{
return(action(subscribedCancellationSource.Token));
});
_logger.LogDebug($"Finished processing for key: {key}");
await _databaseAsync.StringIncrementAsync(key);
return(response);
}
catch (Exception ex)
{
throw new DistributedCancellationException("An exception happened", ex);
}
finally
{
await @lock.ReleaseAsync();
await _redisSubscriber.UnsubscribeAsync(key).ConfigureAwait(false);
}
}