/// <summary>
/// Creates an invalid instance of the given reactive entity kind with the given URI.
/// </summary>
/// <param name="uri">The URI.</param>
/// <param name="kind">The reactive entity kind.</param>
/// <returns>
/// The invalid instance, or null if an unexpected kind is provided.
/// </returns>
public static ReactiveEntity CreateInvalidInstance(Uri uri, ReactiveEntityKind kind)
{
return(kind switch
{
ReactiveEntityKind.Observable => ObservableDefinitionEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.Observer => ObserverDefinitionEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.Stream => SubjectEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.StreamFactory => StreamFactoryDefinitionEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.Subscription => SubscriptionEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.ReliableSubscription => ReliableSubscriptionEntity.CreateInvalidInstance(uri),
ReactiveEntityKind.Template or ReactiveEntityKind.Other => OtherDefinitionEntity.CreateInvalidInstance(uri),
_ => null,
});
/// <summary>
/// Predicate defining whether the subscription state should be included in the checkpoint.
/// </summary>
/// <param name="entity">The entity.</param>
/// <returns>
/// True if should be included.
/// </returns>
protected override bool ShouldSaveSubscriptionState(SubscriptionEntity entity)
{
Debug.Assert(entity != null, "Entity should not be null.");
var instance = entity.Instance;
if (instance != null)
{
return(SubscriptionStateVisitor.HasStateChanged(instance));
}
return(false);
}
/// <summary>
/// Saves subscription runtime state.
/// </summary>
/// <param name="entity">The entity to save.</param>
/// <param name="stream">The stream to save to.</param>
protected virtual void SaveSubscriptionState(SubscriptionEntity entity, Stream stream)
{
Debug.Assert(entity != null, "Entity should not be null.");
Debug.Assert(stream != null, "Stream should not be null.");
var instance = entity.Instance;
if (instance != null)
{
var policy = _engine.Parent._serializationPolicy;
using (entity.Measure(EntityMetric.SaveState))
{
using var operatorStateWriter = new OperatorStateWriterFactory(stream, policy);
operatorStateWriter.WriteHeader();
SubscriptionStateVisitor.SaveState(instance, operatorStateWriter);
}
}
}
private void AddEntityPlaceholder(ReactiveEntityKind kind, string key)
{
var uri = new Uri(key);
#pragma warning disable IDE0079 // Remove unnecessary suppression.
#pragma warning disable CA2000 // Dispose objects before losing scope. (Entities are owned by the registry.)
var added = kind switch
{
ReactiveEntityKind.Observable => Registry.Observables.TryAdd(key, ObservableDefinitionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.Observer => Registry.Observers.TryAdd(key, ObserverDefinitionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.Stream => Registry.Subjects.TryAdd(key, SubjectEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.StreamFactory => Registry.SubjectFactories.TryAdd(key, StreamFactoryDefinitionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.SubscriptionFactory => Registry.SubscriptionFactories.TryAdd(key, SubscriptionFactoryDefinitionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.Subscription => Registry.Subscriptions.TryAdd(key, SubscriptionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.ReliableSubscription => Registry.ReliableSubscriptions.TryAdd(key, ReliableSubscriptionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.Other => Registry.Other.TryAdd(key, OtherDefinitionEntity.CreateInvalidInstance(uri)),
ReactiveEntityKind.Template => Registry.Templates.TryAdd(key, OtherDefinitionEntity.CreateInvalidInstance(uri)),
_ => throw new InvalidOperationException(string.Format(CultureInfo.InvariantCulture, "Cannot create an invalid entity '{0}' of type '{1}'.", key, kind)),
};
#pragma warning restore CA2000
#pragma warning restore IDE0079
if (added)
{
Parent.TraceSource.Registry_AddEntityPlaceholder(Parent.Uri, kind.ToString(), key);
}
}
/// <summary> /// Predicate defining whether the subscription state should be included in the checkpoint. /// </summary> /// <param name="entity">The entity.</param> /// <returns> /// True if should be included. /// </returns> protected override bool ShouldSaveSubscriptionState(SubscriptionEntity entity) => true;
/// <summary> /// Predicate defining whether the subscription state should be included in the checkpoint. /// </summary> /// <param name="entity">The entity.</param> /// <returns>True if should be included.</returns> protected abstract bool ShouldSaveSubscriptionState(SubscriptionEntity entity);