/// <summary>
/// Returns the implementation of the <see cref="ICloudQueueStorage"/> that corresponds to the Azure storage as defined in the specified location object.
/// </summary>
/// <param name="location">The specified location of a queue in the Azure storage infrastructure.</param>
/// <returns>The object that provides access to the Azure queue storage.</returns>
public ICloudQueueStorage GetQueueStorage(CloudQueueLocation location)
{
Guard.ArgumentNotNull(location, "location");
Guard.ArgumentNotNull(this.cloudStorageProvider, "cloudStorageProvider");
return(this.cloudStorageProvider.GetQueueStorage(location.StorageAccount));
}
/// <summary>
/// Initializes a new instance of a queue listener that will be listening to messages arriving to the specified queue.
/// </summary>
/// <param name="queueLocation">The location of a queue in the Windows Azure storage infrastructure.</param>
public CloudQueueListenerExtension(CloudQueueLocation queueLocation)
{
Guard.ArgumentNotNull(queueLocation, "queueLocation");
Guard.ArgumentNotNullOrEmptyString(queueLocation.QueueName, "queueLocation.QueueName");
this.queueLocation = queueLocation;
this.dequeueTasks = new BlockingCollection <Task>(this.dequeueTaskList);
this.DequeueBatchSize = DefaultDequeueBatchSize;
this.DequeueInterval = TimeSpan.FromMilliseconds(DefaultDequeueMaxReceiveInterval);
}
public CloudQueueListenerDequeueTaskState(IEnumerable <QueueSubscriptionInfo <TItem> > subscriptions, CancellationToken cancellationToken, CloudQueueLocation queueLocation, ICloudQueueStorage queueStorage)
{
Guard.ArgumentNotNull(subscriptions, "subscriptions");
Guard.ArgumentNotNull(cancellationToken, "cancellationToken");
Guard.ArgumentNotNull(queueLocation, "queueLocation");
Guard.ArgumentNotNull(queueStorage, "queueStorage");
this.subscriptions = subscriptions;
this.cancellationToken = cancellationToken;
this.queueLocation = queueLocation;
this.queueStorage = queueStorage;
}
/// <summary>
/// Notifies this extension component that it has been registered in the owner's collection of extensions.
/// </summary>
/// <param name="owner">The extensible owner object that aggregates this extension.</param>
public void Attach(IExtensibleCloudServiceComponent owner)
{
var callToken = TraceManager.WorkerRoleComponent.TraceIn(this.queueLocation.StorageAccount, this.queueLocation.QueueName);
try
{
owner.Extensions.Demand <ICloudStorageProviderExtension>();
if (!this.queueLocation.IsDiscoverable)
{
var queueLocationResolvers = owner.Extensions.FindAll <ICloudQueueLocationResolverExtension>();
foreach (ICloudQueueLocationResolverExtension locationResolver in queueLocationResolvers)
{
this.queueLocation = locationResolver.GetQueueLocation(this.queueLocation.QueueName);
if (this.queueLocation.IsDiscoverable)
{
break;
}
}
}
if (this.queueLocation.IsDiscoverable)
{
ICloudStorageProviderExtension storageProvider = owner.Extensions.Find <ICloudStorageProviderExtension>();
this.queueStorage = storageProvider.GetQueueStorage(this.queueLocation.StorageAccount);
// Ensure that the queue is available, create a new queue if one doesn't exist.
this.queueStorage.CreateQueue(this.queueLocation.QueueName);
}
else
{
throw new CloudApplicationException(String.Format(CultureInfo.CurrentCulture, ExceptionMessages.CloudQueueNotDiscoverable, this.queueLocation.QueueName));
}
}
finally
{
TraceManager.WorkerRoleComponent.TraceOut(callToken);
}
}
/// <summary>
/// Resolves the exact location of a given queue by its name.
/// </summary>
/// <param name="queueName">The name of the Windows Azure queue.</param>
/// <returns>The location of the queue in the Windows Azure storage infrastructure.</returns>
public CloudQueueLocation GetQueueLocation(string queueName)
{
Guard.ArgumentNotNullOrEmptyString(queueName, "queueName");
var callToken = TraceManager.WorkerRoleComponent.TraceIn(queueName);
// Assume an invalid (non-discoverable) location by default.
CloudQueueLocation queueLocation = CloudQueueLocation.Unknown;
try
{
if (queueName == "InputQueueTag")
{
queueLocation = new CloudQueueLocation()
{
StorageAccount = this.configSettingsExtension.Settings.CloudStorageAccount,
QueueName = this.configSettingsExtension.Settings.WorkItemQueue,
VisibilityTimeout = this.configSettingsExtension.Settings.WorkItemQueueVisibilityTimeout
};
}
else if (queueName == "OutputQueueTag")
{
queueLocation = new CloudQueueLocation()
{
StorageAccount = this.configSettingsExtension.Settings.CloudStorageAccount,
QueueName = this.configSettingsExtension.Settings.OutputQueue,
VisibilityTimeout = this.configSettingsExtension.Settings.OutputQueueVisibilityTimeout
};
}
}
finally
{
TraceManager.WorkerRoleComponent.TraceOut(callToken, queueLocation.QueueName, queueLocation.StorageAccount, queueLocation.VisibilityTimeout);
}
return(queueLocation);
}
/// <summary>
/// Extends the OnStart phase that is called by Windows Azure runtime to initialize the role instance.
/// </summary>
/// <returns>True if initialization succeeds, otherwise false.</returns>
protected override bool OnRoleStart()
{
this.EnsureExists <WorkItemProcessorConfigurationExtension>();
this.EnsureExists <WorkQueueLocationResolverExtension>();
this.EnsureExists <ScalableTransformServiceClientExtension>();
this.EnsureExists <EndpointConfigurationDiscoveryExtension>();
this.EnsureExists <RulesEngineServiceClientExtension>();
this.EnsureExists <InterRoleEventSubscriberExtension>();
IWorkItemProcessorConfigurationExtension configSettingsExtension = Extensions.Find <IWorkItemProcessorConfigurationExtension>();
IEndpointConfigurationDiscoveryExtension discoveryExtension = Extensions.Find <IEndpointConfigurationDiscoveryExtension>();
IInterRoleCommunicationExtension interCommExtension = Extensions.Find <IInterRoleCommunicationExtension>();
IInterRoleEventSubscriberExtension interCommSubscriber = Extensions.Find <IInterRoleEventSubscriberExtension>();
CloudQueueLocation inputQueueLocation = new CloudQueueLocation()
{
StorageAccount = configSettingsExtension.Settings.CloudStorageAccount,
QueueName = configSettingsExtension.Settings.WorkItemQueue,
VisibilityTimeout = configSettingsExtension.Settings.WorkItemQueueVisibilityTimeout
};
CloudQueueLocation outputQueueLocation = new CloudQueueLocation()
{
StorageAccount = configSettingsExtension.Settings.CloudStorageAccount,
QueueName = configSettingsExtension.Settings.OutputQueue,
VisibilityTimeout = configSettingsExtension.Settings.OutputQueueVisibilityTimeout
};
// Instantiate queue listeners.
var inputQueueListener = new CloudQueueListenerExtension <XDocument>(inputQueueLocation);
var outputQueueListener = new CloudQueueListenerExtension <XDocument>(outputQueueLocation);
// Configure the input queue listener.
inputQueueListener.QueueEmpty += HandleQueueEmptyEvent;
inputQueueListener.DequeueBatchSize = configSettingsExtension.Settings.DequeueBatchSize;
inputQueueListener.DequeueInterval = configSettingsExtension.Settings.MinimumIdleInterval;
// Configure the output queue listener.
outputQueueListener.QueueEmpty += HandleQueueEmptyEvent;
outputQueueListener.DequeueBatchSize = configSettingsExtension.Settings.DequeueBatchSize;
outputQueueListener.DequeueInterval = configSettingsExtension.Settings.MinimumIdleInterval;
// Instantiate queue subscribers.
InputQueueSubscriberExtension inputQueueSubscriber = new InputQueueSubscriberExtension();
OutputQueueSubscriberExtension outputQueueSubscriber = new OutputQueueSubscriberExtension();
// Register subscribers with queue listeners.
inputQueueListener.Subscribe(inputQueueSubscriber);
outputQueueListener.Subscribe(outputQueueSubscriber);
// Register custom extensions for this worker role.
Extensions.Add(inputQueueSubscriber);
Extensions.Add(outputQueueSubscriber);
Extensions.Add(outputQueueListener);
Extensions.Add(inputQueueListener);
var contractTypeMatchCondition = ServiceEndpointDiscoveryCondition.ContractTypeExactMatch(typeof(IScalableTransformationServiceContract));
var bindingTypeMatchCondition = ServiceEndpointDiscoveryCondition.BindingTypeExactMatch(typeof(NetTcpRelayBinding));
discoveryExtension.RegisterDiscoveryAction(new[] { contractTypeMatchCondition, bindingTypeMatchCondition }, (endpoint) =>
{
NetTcpRelayBinding relayBinding = endpoint.Binding as NetTcpRelayBinding;
if (relayBinding != null)
{
relayBinding.TransferMode = TransferMode.Streamed;
}
});
// Register a subscriber for all inter-role communication events.
if (interCommExtension != null && interCommSubscriber != null)
{
this.interCommSubscription = interCommExtension.Subscribe(interCommSubscriber);
}
return(true);
}
