/// <summary>
/// Called when the state was persisted.
/// </summary>
public void OnSaved()
{
_registry.TruncateLoggedEntities(_snapshot);
foreach (var entity in _snapshot.Entities)
{
entity.OnPersisted();
}
foreach (var subject in _snapshot.Subjects.Values)
{
if (subject.Instance is IStatefulOperator op)
{
op.OnStateSaved();
}
}
foreach (var subscription in _snapshot.Subscriptions.Values)
{
var instance = subscription.Instance;
if (instance != null)
{
SubscriptionStateVisitor.OnStateSaved(instance);
}
}
}
/// <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);
}
}
}
public void SubscriptionStateVisitor_Basics()
{
var state = new MockOperatorStateContainer();
var writerFactory = state.CreateWriter();
var readerFactory = state.CreateReader();
var xs = new SimpleSubject <int>();
var o = xs.CreateObserver();
var ys = new Take <int>(xs, 5);
{
var s1 = ys.Subscribe(Observer.Create <int>(_ => { }, _ => { }, () => { }));
var v = new SubscriptionInitializeVisitor(s1);
v.Subscribe();
v.Start();
o.OnNext(42);
o.OnNext(43);
var sv = new SubscriptionStateVisitor(s1);
Assert.IsTrue(sv.HasStateChanged());
sv.SaveState(writerFactory);
Assert.IsTrue(sv.HasStateChanged());
sv.OnStateSaved();
Assert.IsFalse(sv.HasStateChanged());
o.OnNext(44);
o.OnNext(45);
Assert.IsTrue(sv.HasStateChanged());
}
{
var done = false;
var s2 = ys.Subscribe(Observer.Create <int>(_ => { }, _ => { }, () => { done = true; }));
var sv = new SubscriptionStateVisitor(s2);
sv.LoadState(readerFactory);
var v = new SubscriptionInitializeVisitor(s2);
v.Subscribe();
v.Start();
o.OnNext(46);
Assert.IsFalse(done);
o.OnNext(47);
Assert.IsFalse(done);
o.OnNext(48);
Assert.IsTrue(done);
}
}
public override void Accept(ISubscription subscription)
{
var visitor = new SubscriptionStateVisitor(subscription);
visitor.SaveState(_state.CreateWriter());
}
public override void Accept(ISubscription subscription)
{
var visitor = new SubscriptionStateVisitor(subscription);
visitor.LoadState(_state.CreateReader());
}
