/// <summary>
/// Provides the observer with new data. This method is invoked by an observable.
/// </summary>
/// <param name="topic">The topic.</param>
/// <param name="message">The current notification information.</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 NotifyObserverAsync(string topic, Message message, EntityId entityId, IEnumerable <EntityId> observers)
{
EntityId id = null;
for (int k = 1; k <= ConfigurationHelper.MaxQueryRetryCount; k++)
{
try
{
id = await this.GetEntityIdAsync();
break;
}
catch (FabricTransientException ex)
{
ServiceEventSource.Current.Error(ex);
if (k == ConfigurationHelper.MaxQueryRetryCount)
{
throw new TimeoutException(Constants.RetryTimeoutExhausted);
}
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ServiceEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ServiceEventSource.Current.Error(ex);
throw;
}
await Task.Delay(ConfigurationHelper.BackoffQueryDelay);
}
try
{
ServiceEventSource.Current.Message(
$"Message Received.\r\n[Observable]: {entityId}\r\n[Observer]: {id}\r\n[Message]: Topic=[{topic}] Body=[{message?.Body ?? "NULL"}]");
if (observers != null)
{
IList <EntityId> observerList = observers as IList <EntityId> ?? observers.ToList();
if (observerList.Any())
{
StringBuilder builder = new StringBuilder($"Observer Proxy:\r\n[From]: {id}");
foreach (EntityId item in observerList)
{
builder.Append($"\r\n[To]: {item}");
}
ServiceEventSource.Current.Message(builder.ToString());
List <Task> taskList = new List <Task>();
taskList.AddRange(
observerList.Select(
observer => ProcessingHelper.NotifyObserverAsync(
topic,
message,
observer,
entityId,
null)));
await Task.WhenAll(taskList.ToArray());
}
}
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ServiceEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ServiceEventSource.Current.Error(ex);
throw;
}
if (this.NotificationMessageReceived == null)
{
return;
}
try
{
Delegate[] invocationList = this.NotificationMessageReceived.GetInvocationList();
Task[] handlerTasks = new Task[invocationList.Length];
NotificationEventArgs <Message> args = new NotificationEventArgs <Message>(topic, message, entityId);
for (int i = 0; i < invocationList.Length; i++)
{
handlerTasks[i] = ProcessingHelper.ExecuteEventHandlerAsync((Func <NotificationEventArgs <Message>, Task>)invocationList[i], args);
}
await Task.WhenAll(handlerTasks);
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ServiceEventSource.Current.Error(e);
}
}
catch (Exception ex)
{
ServiceEventSource.Current.Error(ex);
}
}
/// <summary>
/// Provides the observer with new data. This method is invoked by an observable.
/// </summary>
/// <param name="topic">The topic.</param>
/// <param name="message">The current notification information.</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 virtual async Task NotifyObserverAsync(string topic, Message message, EntityId entityId, IEnumerable <EntityId> observers)
{
try
{
EntityId id = await this.GetEntityIdAsync();
if (id == null)
{
return;
}
if (entityId == null)
{
entityId = new EntityId {
ActorId = ActorId.CreateRandom(), ServiceUri = this.ServiceUri
}
}
;
ActorEventSource.Current.Message(
$"Message Received.\r\n[Observable]: {entityId}\r\n[Observer]: {id}\r\n[Message]: Topic=[{topic}] Body=[{message?.Body ?? "NULL"}]");
if (observers != null)
{
IList <EntityId> observerList = observers as IList <EntityId> ?? observers.ToList();
if (observerList.Any())
{
StringBuilder builder = new StringBuilder($"Observer Proxy:\r\n[From]: {id}");
foreach (EntityId item in observerList)
{
builder.Append($"\r\n[To]: {item}");
}
ActorEventSource.Current.Message(builder.ToString());
List <Task> taskList = new List <Task>();
taskList.AddRange(
observerList.Select(
observer => ProcessingHelper.NotifyObserverAsync(
topic,
message,
observer,
entityId,
null)));
await Task.WhenAll(taskList.ToArray());
}
}
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
throw;
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
throw;
}
if (this.NotificationMessageReceived == null)
{
return;
}
try
{
Delegate[] invocationList = this.NotificationMessageReceived.GetInvocationList();
Task[] handlerTasks = new Task[invocationList.Length];
NotificationEventArgs <Message> args = new NotificationEventArgs <Message>(topic, message, entityId);
for (int i = 0; i < invocationList.Length; i++)
{
handlerTasks[i] = ProcessingHelper.ExecuteEventHandlerAsync((Func <NotificationEventArgs <Message>, Task>)invocationList[i], args);
}
await Task.WhenAll(handlerTasks);
}
catch (AggregateException ex)
{
foreach (Exception e in ex.InnerExceptions)
{
ActorEventSource.Current.Error(e);
}
}
catch (Exception ex)
{
ActorEventSource.Current.Error(ex);
}
}
/// <summary>
/// Sends data to observers for a given topic.
/// </summary>
/// <param name="topic">The topic.</param>
/// <param name="message">The current notification information.</param>
/// <param name="useObserverAsProxy">Observable uses one observer for each cluster node as a proxy when true,
/// it directly sends the message to all observers otherwise.</param>
/// <returns>The asynchronous result of the operation.</returns>
public async Task NotifyObserversAsync(string topic, Message message, bool useObserverAsProxy)
{
EntityId id = await this.GetEntityIdAsync();
if (id == null)
{
return;
}
if (string.IsNullOrWhiteSpace(topic))
{
throw new ArgumentException($"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($"{id} is not an observable for Topic=[{topic}]");
}
Dictionary <Uri, ObserverInfo> observerDictionary = topicState.Value;
if (string.IsNullOrWhiteSpace(message?.Body))
{
throw new ArgumentException($"The {nameof(message)} parameter cannot be null.", nameof(message));
}
try
{
List <Task> taskList = new List <Task>();
if (useObserverAsProxy)
{
if (JsonSerializerHelper.IsJson(message.Body))
{
// Create the list of observers: an observer is added to the list only at least of of its
// filter predicates is satisified by the message.
JObject jObject = JsonSerializerHelper.Deserialize(message.Body);
IEnumerable <EntityId> observerEnumerable = (from subscriptionInfo in observerDictionary.
Where(kvp => kvp.Value.Predicates.Any()).
Select(observer => observer.Value)
let ok = subscriptionInfo.Predicates.Any(predicate => predicate(jObject))
where ok
select subscriptionInfo.EntityId);
// observers are grouped by NodeName
taskList.AddRange(
observerEnumerable.
GroupBy(e => e.NodeName).
Select(groupingByNodeName => ProcessingHelper.GetObserverProxyAndList(groupingByNodeName, true)).
Select(tuple => ProcessingHelper.NotifyObserverAsync(topic, message, tuple.Item1, id, tuple.Item2)));
}
else
{
// 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.NotifyObserverAsync(topic, message, tuple.Item1, id, tuple.Item2)));
}
}
else
{
if (JsonSerializerHelper.IsJson(message.Body))
{
JObject jObject = JsonSerializerHelper.Deserialize(message.Body);
taskList.AddRange(
(from subscriptionInfo in observerDictionary.
Where(kvp => kvp.Value.Predicates.Any()).
Select(observer => observer.Value)
let ok = subscriptionInfo.Predicates.Any(predicate => predicate(jObject))
where ok
select subscriptionInfo.EntityId).
Select(
entityId => ProcessingHelper.NotifyObserverAsync(
topic,
message,
entityId,
id,
null)));
}
else
{
taskList.AddRange(
observerDictionary.Select(
observer => ProcessingHelper.NotifyObserverAsync(
topic,
message,
observer.Value.EntityId,
id,
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;
}
}
