public void Extrapolate(IEvent @event)
{
var events = _eventStream.Where(e => e.Kind == EventKinds.AnimalIntoMob).ToList();
var subjects = events.Select(e => e.Subject).Distinct();
_store.Clear();
foreach (var sub in subjects)
{
var subjectEvents = events.Where(e => e.Subject == sub)
.Select(e => JsonConvert.DeserializeObject <AnimalIntoMobObservation>(e.Data))
.OrderBy(o => o.Observed);
AnimalMobHistory previous = null;
foreach (var subEvent in subjectEvents)
{
if (previous == null)
{
previous = new AnimalMobHistory()
{
AnimalId = subEvent.AnimalId,
MobId = subEvent.MobId,
DateIn = subEvent.Observed
};
_store.Add(previous);
continue;
}
var current = new AnimalMobHistory()
{
AnimalId = subEvent.AnimalId,
MobId = subEvent.MobId,
DateIn = subEvent.Observed
};
previous.DateOut = subEvent.Observed;
_store.Add(current);
}
var latest = DataStore.DataStore.AnimalMobHistories.Where(h => h.AnimalId == sub)
.OrderByDescending(h => h.DateIn).FirstOrDefault();
if (latest == null)
{
continue;
}
var animal = DataStore.DataStore.Animals.First(a => a.Id == latest.AnimalId);
animal.MobId = latest.MobId;
DataStore.DataStore.Animals.Update(animal);
}
}
private TAggregateRootState CreateState(IEventStream stream)
{
Contract.Requires(stream != null);
Contract.Ensures(Contract.Result <TAggregateRootState>() != null);
var snapshotRevision = stream.FirstOrDefault(x => x is SnapshotRevision) as SnapshotRevision;
// order domain events and flatten list
IReadOnlyCollection <IDomainEvent> domainEvents = stream.Where(x => x is DomainEventRevision)
.OrderBy(x => x.Version)
.Cast <DomainEventRevision>()
.SelectMany(x => x.DomainEvents)
.ToList();
var domainEventsExist = domainEvents.Any();
TAggregateRootState state;
// check for valid stream
if (snapshotRevision == null)
{
if (domainEventsExist)
{
// domain events only
state = _aggregateRootStateBuilder.Build(domainEvents);
}
else
{
throw new InvalidOperationException("Event stream does not contain a snapshot or domain event revision.");
}
}
else
{
if (domainEventsExist)
{
// snapshot and domain events
state = _aggregateRootStateBuilder.Build(snapshotRevision.Snapshot.Data, domainEvents);
}
else
{
// snapshot only
state = _aggregateRootStateBuilder.Build(snapshotRevision.Snapshot.Data);
}
}
Contract.Assume(state != null);
return(state);
}