Fix racy CurrentEventsByTag_should_find_existing_events test - #76
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Fix racy CurrentEventsByTag_should_find_existing_events test#76Aaronontheweb wants to merge 2 commits into
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Override the base TCK test to account for EventStore's eventually consistent projections. The base test uses backpressure (Request 2, ExpectNoMsg, Request 2) to page through a tagged stream, but the EventStore projection may complete before all events are indexed, causing OnComplete to race with ExpectNoMsg. The override adds a 300ms delay for projection catch-up and requests all events at once, consistent with the existing override pattern used by ReadJournal_query_CurrentEventsByTag_should_see_all_150_events.
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… catch-up EventStore projections are eventually consistent. Instead of sleeping for an arbitrary duration and hoping the projection has caught up, poll the projection using AwaitConditionAsync until the expected number of events are indexed. This eliminates the race condition that caused flaky failures in CurrentEventsByTag_should_find_existing_events. Also fixes the same non-deterministic pattern in the 150-event test and the offset exclusivity test.
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Add a protected virtual extensibility point to CurrentAllEventsSpec, CurrentEventsByTagSpec, and CurrentEventsByPersistenceIdSpec that is called after events are written and before queries are executed. Backends with eventually-consistent read models (EventStore, Kafka, etc.) can override this method to wait for their read side to catch up, instead of being forced to override entire TCK test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76
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Replace the virtual WaitForReadSideAsync() hook with inline polling using AwaitConditionAsync. Each test now polls its respective Current* query until the expected number of events are indexed before running assertions. This is deterministic: synchronous backends pass on the first poll, eventually-consistent backends converge. Fixes the root cause of flaky TCK failures in backends like EventStore where projections are eventually consistent. Previously, these backends were forced to override entire test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76
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* Add WaitForReadSideAsync() hook to Persistence TCK query specs Add a protected virtual extensibility point to CurrentAllEventsSpec, CurrentEventsByTagSpec, and CurrentEventsByPersistenceIdSpec that is called after events are written and before queries are executed. Backends with eventually-consistent read models (EventStore, Kafka, etc.) can override this method to wait for their read side to catch up, instead of being forced to override entire TCK test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76 * Make TCK query specs tolerant of eventually-consistent backends Replace the virtual WaitForReadSideAsync() hook with inline polling using AwaitConditionAsync. Each test now polls its respective Current* query until the expected number of events are indexed before running assertions. This is deterministic: synchronous backends pass on the first poll, eventually-consistent backends converge. Fixes the root cause of flaky TCK failures in backends like EventStore where projections are eventually consistent. Previously, these backends were forced to override entire test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76
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* Add WaitForReadSideAsync() hook to Persistence TCK query specs Add a protected virtual extensibility point to CurrentAllEventsSpec, CurrentEventsByTagSpec, and CurrentEventsByPersistenceIdSpec that is called after events are written and before queries are executed. Backends with eventually-consistent read models (EventStore, Kafka, etc.) can override this method to wait for their read side to catch up, instead of being forced to override entire TCK test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76 * Make TCK query specs tolerant of eventually-consistent backends Replace the virtual WaitForReadSideAsync() hook with inline polling using AwaitConditionAsync. Each test now polls its respective Current* query until the expected number of events are indexed before running assertions. This is deterministic: synchronous backends pass on the first poll, eventually-consistent backends converge. Fixes the root cause of flaky TCK failures in backends like EventStore where projections are eventually consistent. Previously, these backends were forced to override entire test methods with Thread.Sleep hacks. Evidence: akkadotnet/Akka.Persistence.EventStore#76
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Summary
ReadJournal_query_CurrentEventsByTag_should_find_existing_eventsfrom the base TCKCurrentEventsByTagSpecto fix a flaky test caused by EventStore's eventually consistent projectionsRequest(2),ExpectNoMsg,Request(2)) against a projected tag stream, butOnCompleteraces withExpectNoMsgwhen the projection hasn't indexed all events yetReadJournal_query_CurrentEventsByTag_should_see_all_150_eventsRoot Cause
The base TCK test writes 6 events (3 tagged "green"), then immediately queries
CurrentEventsByTag("green", NoOffset). It requests only 2 items, expects them, then callsExpectNoMsg(500ms)before requesting more. However, EventStore projections are eventually consistent -- the projected tag stream may only contain the first 2 green events when queried, causing the stream to complete immediately andOnCompleteto arrive during theExpectNoMsgwindow (observed arriving after just 36 nanoseconds).Test plan
OnCompleteduringExpectNoMsg)