/// <summary>
/// Unregisters an observable. This method is invoked by an observable.
/// </summary>
/// <param name="topic">The topic.</param>
/// <param name="entityId">The entity id of the observable.</param>
/// <param name="observers">
/// A list of observers in the same cluster node. This field is optional.
/// When the list if not null or empty, the observer will forward the message to each observer which EntityId is in the
/// list.
/// </param>
/// <returns>The asynchronous result of the operation.</returns>
public async Task UnregisterObservableAsync(string topic, EntityId entityId, IEnumerable <EntityId> observers)
{
EntityId id = await this.GetEntityIdAsync();
if (id == null)
{
return;
}
if (string.IsNullOrWhiteSpace(topic))
{
throw new ArgumentException($"The {nameof(topic)} parameter cannot be null.", nameof(topic));
}
if (entityId == null)
{
throw new ArgumentException($"The {nameof(entityId)} parameter cannot be null.", nameof(entityId));
}
for (int k = 1; k <= ConfigurationHelper.MaxQueryRetryCount; k++)
{
try
{
ConditionalValue <Dictionary <Uri, EntityId> > topicState = await this.StateManager.TryGetStateAsync <Dictionary <Uri, EntityId> >(topic);
if (!topicState.HasValue)
{
ActorEventSource.Current.Message(
$"Observer not registered to the specified topic.\r\n[Observable]: {entityId}\r\n[Observer]: {id}\r\n[Publication]: Topic=[{topic}]");
return;
}
Dictionary <Uri, EntityId> observableDictionary = topicState.Value;
if (!observableDictionary.ContainsKey(entityId.EntityUri))
{
ActorEventSource.Current.Message(
$"Observer not registered to the specified observable.\r\n[Observable]: {entityId}\r\n[Observer]: {id}\r\n[Publication]: Topic=[{topic}]");
return;
}
observableDictionary.Remove(entityId.EntityUri);
if (!observableDictionary.Any())
{
await this.StateManager.TryRemoveStateAsync(topic);
}
else
{
await this.StateManager.SetStateAsync(topic, observableDictionary);
}
ActorEventSource.Current.Message(
$"Observable successfully unregistered.\r\n[Observable]: {entityId}\r\n[Observer]: {id}\r\n[Publication]: Topic=[{topic}]");
break;
}
catch (FabricTransientException ex)
{
ActorEventSource.Current.Error(ex);
if (k == ConfigurationHelper.MaxQueryRetryCount)
{
throw new TimeoutException(Constants.RetryTimeoutExhausted);
}
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
throw;
}
await Task.Delay(ConfigurationHelper.BackoffQueryDelay);
}
try
{
if (observers != null)
{
IList <EntityId> observerList = observers as IList <EntityId> ?? observers.ToList();
if (observerList.Any())
{
StringBuilder builder = new StringBuilder($"Observer Proxy:\r\n[From]: {id}");
foreach (EntityId item in observerList)
{
builder.Append($"\r\n[To]: {item}");
}
ActorEventSource.Current.Message(builder.ToString());
List <Task> taskList = new List <Task>();
taskList.AddRange(observerList.Select(observer => ProcessingHelper.UnregisterObservableAsync(topic, observer, entityId, null)));
await Task.WhenAll(taskList.ToArray());
}
}
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
throw;
}
if (this.ObservableUnregistered == null)
{
return;
}
try
{
Delegate[] invocationList = this.ObservableUnregistered.GetInvocationList();
Task[] handlerTasks = new Task[invocationList.Length];
SubscriptionEventArgs args = new SubscriptionEventArgs(topic, entityId);
for (int i = 0; i < invocationList.Length; i++)
{
handlerTasks[i] = ProcessingHelper.ExecuteEventHandlerAsync((Func <SubscriptionEventArgs, Task>)invocationList[i], args);
}
await Task.WhenAll(handlerTasks);
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
}
}
/// <summary>
/// Unregisters an entity as observable for a given topic.
/// This method is called by a management service or actor.
/// </summary>
/// <param name="topic">The topic.</param>
/// <param name="useObserverAsProxy">Observable uses one observer for each cluster node as a proxy when true,
/// it directly sends the message to all observers otherwise.</param>
/// <returns>The asynchronous result of the operation.</returns>
public async Task UnregisterObservableActorAsync(string topic, bool useObserverAsProxy)
{
EntityId id = await this.GetEntityIdAsync();
if (id == null)
{
return;
}
if (string.IsNullOrWhiteSpace(topic))
{
throw new ArgumentException($"The {nameof(topic)} parameter cannot be null.", nameof(topic));
}
ConditionalValue <Dictionary <Uri, ObserverInfo> > topicState = await this.StateManager.TryGetStateAsync <Dictionary <Uri, ObserverInfo> >(topic);
if (!topicState.HasValue)
{
throw new ArgumentException($"{id} is not an observable for Topic=[{topic}]");
}
Dictionary <Uri, ObserverInfo> observerDictionary = topicState.Value;
try
{
for (int k = 1; k <= ConfigurationHelper.MaxQueryRetryCount; k++)
{
try
{
IRegistryService registryService = ServiceProxy.Create <IRegistryService>(ConfigurationHelper.RegistryServiceUri,
new ServicePartitionKey(PartitionResolver.Resolve(topic, ConfigurationHelper.RegistryServicePartitionCount)));
await registryService.UnregisterObservableAsync(topic, id);
break;
}
catch (FabricTransientException ex)
{
ActorEventSource.Current.Error(ex);
if (k == ConfigurationHelper.MaxQueryRetryCount)
{
throw;
}
}
catch (AggregateException ex)
{
foreach (Exception innerException in ex.InnerExceptions)
{
ActorEventSource.Current.Error(innerException);
}
if (k == ConfigurationHelper.MaxQueryRetryCount)
{
throw;
}
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
if (k == ConfigurationHelper.MaxQueryRetryCount)
{
throw;
}
}
await Task.Delay(ConfigurationHelper.BackoffQueryDelay);
}
List <Task> taskList = new List <Task>();
try
{
if (useObserverAsProxy)
{
// observers are grouped by NodeName
taskList.AddRange(
observerDictionary.
Select(kvp => kvp.Value.EntityId).
GroupBy(e => e.NodeName).
Select(groupingByNodeName => ProcessingHelper.GetObserverProxyAndList(groupingByNodeName, true)).
Select(tuple => ProcessingHelper.UnregisterObservableAsync(topic, tuple.Item1, id, tuple.Item2)));
}
else
{
taskList.AddRange(
observerDictionary.Select(
observer => ProcessingHelper.UnregisterObservableAsync(topic, observer.Value.EntityId, id, null)));
}
await Task.WhenAll(taskList.ToArray());
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
}
await this.StateManager.TryRemoveStateAsync(topic);
ActorEventSource.Current.Message($"Observable successfully unregistered.\r\n[Observable]: {id}\r\n[Publication]: Topic=[{topic}].");
}
catch (FabricTransientException ex)
{
ActorEventSource.Current.Error(ex);
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
throw;
}
}
