protected void ApplyAggregateEvent(AggregateEventBase aggregateEvent)
{
Version++;
// TODO: 是否需要 lock?
aggregateEvent.SetAggregateIdAndVersion(Id, Version);
PrivateReflectionDynamicObject.WrapObjectIfNeeded(this).Apply(aggregateEvent);
_aggregateEvents.Add(aggregateEvent);
}
/// <summary>
/// save events to db then apply event to state
/// snapshot will be created for every 10 events
/// Returns id of the newly applied event(from db)
/// </summary>
public async Task <long> ApplyEvents(TEvent[] events, long?rootEventId = null, long?parentEventId = null)
{
var aggregateEvents = new AggregateEventBase[events.Length];
for (int i = 0; i < events.Length; i++)
{
// get event type
var type = events[i].GetType();
// get event type name and version
var eventIdentity = EventTypeHelper.GetEventIdentity(type);
// serialize event for db
var serialized = JsonSerializer.Serialize(events[i], type);
// increment aggregate version
_aggregateVersion++;
// add aggregateeventbase
aggregateEvents[i] = new AggregateEventBase
{
AggregateId = AggregateId,
AggregateVersion = _aggregateVersion,
Type = eventIdentity.Name,
EventVersion = eventIdentity.Version,
Data = serialized,
RootEventId = rootEventId,
ParentEventId = parentEventId,
Created = DateTime.UtcNow
};
}
var eventId = await _repository.SaveEvents(
_aggregateName,
aggregateEvents
);
for (int i = 0; i < events.Length; i++)
{
// update state
_aggregate.Apply(events[i]);
// save snapshot if ShouldSaveSnapshot returns true
if (_shouldSaveSnapshot(events[i], _aggregateVersion))
{
await SaveSnapshot();
}
}
// return id
return(eventId);
}
public async Task Test1()
{
// arrange
var postgresRepo = new PostgresRepository("host=localhost;database=EventSourcing;username=orleans;password=5544338;Enlist=false;Maximum Pool Size=90;");
var events = new AggregateEventBase[]
{
new AggregateEventBase {
AggregateId = 3, AggregateVersion = 6744, EventVersion = 0, ParentEventId = null, RootEventId = null, Type = "TransferDebited", Data = "", Created = DateTime.UtcNow
},
new AggregateEventBase {
AggregateId = 3, AggregateVersion = 6745, EventVersion = 0, ParentEventId = null, RootEventId = null, Type = "TransferDebited", Data = "", Created = DateTime.UtcNow
},
};
// act
var id = await postgresRepo.SaveEvents("account", events);
// assert
Assert.NotEqual(0, id);
}
// deserialize from db event
public static object DeserializeEvent(AggregateEventBase dbEvent)
{
var eventType = EventTypeHelper.GetEventType((dbEvent.Type, dbEvent.EventVersion));
return(JsonSerializer.Deserialize(dbEvent.Data, eventType));
}
