IReliableConcurrentQueue<T>.EnqueueAsync Méthode

public System.Threading.Tasks.Task EnqueueAsync (Microsoft.ServiceFabric.Data.ITransaction tx, T value, System.Threading.CancellationToken cancellationToken = default, TimeSpan? timeout = default);

abstract member EnqueueAsync : Microsoft.ServiceFabric.Data.ITransaction * 'T * System.Threading.CancellationToken * Nullable<TimeSpan> -> System.Threading.Tasks.Task

Public Function EnqueueAsync (tx As ITransaction, value As T, Optional cancellationToken As CancellationToken = Nothing, Optional timeout As Nullable(Of TimeSpan) = Nothing) As Task

Paramètres

Retours

Tâche qui représente l’opération de mise en file d’attente asynchrone.

Exceptions

Exemples

Cet exemple montre comment utiliser EnqueueAsync(ITransaction, T, CancellationToken, Nullable<TimeSpan>) pour mettre en file d’attente une valeur avec une nouvelle tentative.

protected override async Task RunAsync(CancellationToken cancellationToken)
{
    var concurrentQueue = await this.StateManager.GetOrAddAsync<IReliableConcurrentQueue<long>>(new Uri("fabric:/concurrentQueue"));

    while (true)
    {
        cancellationToken.ThrowIfCancellationRequested();

        try
        {
            using (var tx = this.StateManager.CreateTransaction())
            {
                await concurrentQueue.EnqueueAsync(tx, 12L, cancellationToken);
                await tx.CommitAsync();

                return;
            }
        }
        catch (TransactionFaultedException e)
        {
            // This indicates that the transaction was internally faulted by the system. One possible cause for this is that the transaction was long running
            // and blocked a checkpoint. Increasing the "ReliableStateManagerReplicatorSettings.CheckpointThresholdInMB" will help reduce the chances of running into this exception
            Console.WriteLine("Transaction was internally faulted, retrying the transaction: " + e);
        }
        catch (FabricNotPrimaryException e)
        {
            // Gracefully exit RunAsync as the new primary should have RunAsync invoked on it and continue work.
            // If instead enqueue was being executed as part of a client request, the client would be signaled to re-resolve.
            Console.WriteLine("Replica is not primary, exiting RunAsync: " + e);
            return;
        }
        catch (FabricNotReadableException e)
        {
            // Retry until the queue is readable or a different exception is thrown.
            Console.WriteLine("Queue is not readable, retrying the transaction: " + e);
        }
        catch (FabricObjectClosedException e)
        {
            // Gracefully exit RunAsync as this is happening due to replica close.
            // If instead enqueue was being executed as part of a client request, the client would be signaled to re-resolve.
            Console.WriteLine("Replica is closing, exiting RunAsync: " + e);
            return;
        }
        catch (TimeoutException e)
        {
            Console.WriteLine("Encountered TimeoutException during EnqueueAsync, retrying the transaction: " + e);
        }
        catch (FabricTransientException e)
        {
            // Retry until the queue is writable or a different exception is thrown.
            Console.WriteLine("Queue is currently not writable, retrying the transaction: " + e);
        }

        // Delay and retry.
        await Task.Delay(TimeSpan.FromMilliseconds(100), cancellationToken);
    }
}

Remarques

Une TryDequeueAsync(ITransaction, CancellationToken, Nullable<TimeSpan>) opération ne peut pas retourner une valeur pour laquelle son EnqueueAsync(ITransaction, T, CancellationToken, Nullable<TimeSpan>) n’a pas encore été validée. Cela inclut la transaction dans laquelle la valeur a été mise en file d’attente ; par conséquent, IReliableConcurrentQueue<T> ne prend pas en charge la lecture de vos écritures.

S’applique à