public void verify_snapshot_check_version()
{
var id = new TestEventUnfolderId(1);
var unfolder = new TestProjector();
var memento = (EventUnfolderMemento)unfolder.GetSnapshot();
memento.Signature = "OTHER"; //change the version of the memento.
Snapshot s = new Snapshot(id, 2, memento);
_persister.Load("", 1, "").ReturnsForAnyArgs(s);
sut.GetById <TestProjector, TestAggregateQueryModel>(id, 200);
_eventStore.Received().OpenStream("BLAH", id, 0, 200);
}
public void verify_persistence_honor_database_version_when_threshold_passed()
{
var sampleAggregateId = new SampleAggregateId(_counter++);
var aggregate = TestAggregateFactory.Create <SampleAggregate, SampleAggregate.State>(new SampleAggregate.State(), sampleAggregateId);
var memento = new AggregateSnapshot <SampleAggregate.State>()
{
Id = sampleAggregateId, Version = 30, State = new SampleAggregate.State()
};
var snapshot = new Snapshot("Jarvis", sampleAggregateId, 30, memento);
_persister.Load(null, 0, null).ReturnsForAnyArgs(snapshot);
//Simulate the flow of a repository, first operation load the snapshot
_sut.Load(sampleAggregateId, Int32.MaxValue, typeof(SampleAggregate));
//then the repository restored the snapshot
((ISnapshotable)aggregate).Restore(memento);
//now iterate
_persister.DidNotReceiveWithAnyArgs().Persist(null, null);
for (int i = 0; i < NumberOfCommitsBeforeSnapshot; i++)
{
aggregate.Touch();
}
_sut.Snapshot(aggregate, "Jarvis", NumberOfCommitsBeforeSnapshot);
//should be persisted, becauase it is loaded at version 30, but then another snapshotthreshold count of event were raised
_persister.ReceivedWithAnyArgs().Persist(null, aggregate.GetType().FullName);
}
public void verify_snapshot_usage()
{
var id = new TestEventUnfolderId(Interlocked.Increment(ref progressive));
using (var stream = _eventStore.OpenStream("BLAH", id.AsString(), 0, Int32.MaxValue))
{
CommitOneValue(stream, 1);
CommitOneValue(stream, 2);
}
var unfolder = sut.GetById <TestProjector, TestAggregateQueryModel>(id, 1);
var memento = unfolder.GetSnapshot();
Snapshot s = new Snapshot(id.AsString(), 2, memento);
using (var stream = _eventStore.OpenStream("BLAH", id.AsString(), 0, Int32.MaxValue))
{
CommitOneValue(stream, 3);
}
_persister.Load(null, 1, null).ReturnsForAnyArgs(s);
unfolder = sut.GetById <TestProjector, TestAggregateQueryModel>(id, Int32.MaxValue);
var rm = unfolder.GetProjection();
Assert.That(rm.Sum, Is.EqualTo(6));
Assert.That(rm.ListOfInt, Is.EquivalentTo(new[] { 1, 2, 3 }));
}
public TProjector GetById <TProjector, TViewModel>(IIdentity id, Int32 to)
where TProjector : Projector <TViewModel>
where TViewModel : BaseAggregateQueryModel, new()
{
var snapshotTypeName = typeof(TProjector).Name;
var snapshot = _snapshotPersister.Load(id.AsString(), to, snapshotTypeName);
var projector = _factory.Create <TViewModel>(typeof(TProjector), id);
Int32 startsFromEvent = 0;
IMementoEx memento = snapshot == null ? null : (IMementoEx)snapshot.Payload;
if (memento != null)
{
if (!projector.ValidateMemento(memento))
{
_snapshotPersister.Clear(id.AsString(), memento.Version, snapshotTypeName);
}
else
{
projector.Restore(memento);
startsFromEvent = snapshot.StreamRevision;
}
}
using (var events = _eventStore.OpenStream(projector.BucketId, id.AsString(), startsFromEvent, to))
{
Int32 eventCount = 0;
foreach (var evt in events.CommittedEvents)
{
projector.ApplyEvent((DomainEvent)evt.Body);
eventCount++;
}
if (projector.ShouldSnapshot(eventCount))
{
memento = projector.GetSnapshot();
snapshot = new Snapshot(id.AsString(), events.StreamRevision, memento);
_snapshotPersister.Persist(snapshot, snapshotTypeName);
}
}
return((TProjector)projector);
}
public ISnapshot Load(string streamId, int upToVersion, Type aggregateType)
{
//Verify in cache without bothering persistence layer.
var snapshot = _cache.Get(streamId) as ISnapshot;
//if is in cache and version is not greater than version requested you can return
if (_cacheEnabled && snapshot != null && snapshot.StreamRevision <= upToVersion)
{
CacheHitCounter.Increment();
return(snapshot);
}
CacheMissCounter.Increment();
//Try load from persistence medium
var persistedSnapshot = _persister.Load(streamId, upToVersion, aggregateType.FullName);
if (_cacheEnabled && persistedSnapshot != null && upToVersion == Int32.MaxValue)
{
_cache.Set(streamId, persistedSnapshot, _standardCachePolicy);
}
return(persistedSnapshot);
}