public EventSourcedAggregateFactoryTests()
{
eventStreamUpgrader = Substitute.For <IEventStreamUpgrader>();
eventStreamUpgrader.UpgradeStream(null, null).ReturnsForAnyArgs(ci =>
{
var stream = ci.Arg <IEnumerable <IEventMessage <DomainAggregateEvent> > >();
var aggregateMetadata = ci.Arg <IReadOnlyDictionary <string, string> >();
return(eventStreamUpgradeFunc(stream, aggregateMetadata));
});
DomainClassInfo[] domainClasses = new[]
{
new DomainClassInfo(entity1ClassId, null, typeof(MyEntity)),
new DomainClassInfo(entity2ClassId, null, typeof(MyEntity2))
};
entityTypeManager = Substitute.For <IEntityTypeManager>();
entityTypeManager.GetClassInfoByClassId(Guid.Empty)
.ReturnsForAnyArgs(ci => domainClasses.Single(x => x.Id == ci.Arg <Guid>()));
entityTypeManager.TryGetClassInfoByClrType(null)
.ReturnsForAnyArgs(ci => domainClasses.SingleOrDefault(x => x.ClrType == ci.Arg <Type>()));
entityTypeManager.GetClassInfoByClrType(null)
.ReturnsForAnyArgs(ci => domainClasses.Single(x => x.ClrType == ci.Arg <Type>()));
sut = new EventSourcedAggregateFactory(eventStreamUpgrader, new EntityFactory(), entityTypeManager);
}
public IEventSourcedAggregateRoot ConstructAndLoadEntityFromEvents(Guid aggregateId, IReadOnlyDictionary <string, string> eventStreamMetadata,
IReadOnlyCollection <IEventStoreRecord> eventRecords)
{
if (!eventStreamMetadata.TryGetValue(AggregateEventStreamMetadataNames.ClassId, out string classIdString))
{
throw new InvalidOperationException($"Cannot load event sourced aggregate ID {aggregateId}: aggregate class ID not found in event stream metadata");
}
Guid classId = Guid.Parse(classIdString);
Type entityType = entityTypeManager.GetClassInfoByClassId(classId).ClrType;
IEnumerable <IEventMessage <DomainAggregateEvent> > eventMessages;
try
{
eventMessages = eventRecords.Select(EventStoreEventMessage.FromRecord)
.Cast <IEventMessage <DomainAggregateEvent> >();
}
catch (InvalidCastException e)
{
throw new InvalidOperationException(
$"Cannot load event sourced aggregate ID {aggregateId}: event stream contains non-DomainAggregateEvent events",
e);
}
var upgradedEvents = eventStreamUpgrader.UpgradeStream(eventMessages, eventStreamMetadata);
var events = upgradedEvents.Select(x => x.Event).ToArray();
int version = (int)(eventRecords.LastOrDefault()?.AdditionalMetadata.GetAggregateVersion() // use non-upgraded event records to preserve the versions
?? eventRecords.LastOrDefault()?.StreamSequenceNumber
?? 0);
AggregateState state = new AggregateState(version, events);
IEventSourcedAggregateRoot aggregate = (IEventSourcedAggregateRoot)ConstructEntity(entityType, aggregateId);
aggregate.LoadState(state);
return(aggregate);
}
