Subscribing to a stream containing links to deleted events crashes StreamSubscriptionActor

When subscribing with resolveLinkTos=true to a stream that contains event links to events that have been deleted, the StreamSubscriptionActor will terminate with an IllegalArgumentException when the event in question is parsed from the protobuf.

Exception text:

ERROR eventstore.StreamSubscriptionActor - eventstore.CommandNotExpectedException: Expected: ReadStreamEventsCompleted, actual: java.lang.IllegalArgumentException: requirement failed: streamId must not be empty

I can reliably reproduce the exception by writing an event of type “TestType” to a random stream in an ES instance with projections enabled, then deleting said stream and subscribing to “$et-TestType”.

The problem seems to be that EventStore, upon encountering an unresolvable event, will create a ResolvedEvent instance as shown below (excerpt from EventStore.Core/Data/ResolvedEvent.cs):

public static ResolvedEvent ForFailedResolvedLink(EventRecord link, ReadEventResult resolveResult, long? commitPosition = null)
        {
            return new ResolvedEvent(null, link, commitPosition, resolveResult);
        }

The JVM client does not handle this case and just crashes when it encounters a ResolvedEvent that does not, in fact, contain a resolved event.

I would expect the subscription actor to simply ignore any events that are “unresolvable because deleted”, at least when resolveLinkTos is enabled.

[Konfuzzyus]

Verified to work on our system. Thanks for the quick resolution.

[t3hnar]

Fixed in v2.2.2