Add EventStored internal event published to the EventBus when events are
successfully persisted. This allows observability components (metrics,
projections, audit systems) to react to persisted events without coupling
to application code.
Implementation:
- Add EventTypeEventStored constant to define the event type
- Update InMemoryEventStore with optional EventBroadcaster support
- Add NewInMemoryEventStoreWithBroadcaster constructor
- Update JetStreamEventStore with EventBroadcaster support
- Add NewJetStreamEventStoreWithBroadcaster constructor
- Implement publishEventStored() helper method
- Publish EventStored containing EventID, ActorID, Version, Timestamp
- Only publish on successful SaveEvent (not on version conflicts)
- Automatically recorded in metrics through normal Publish flow
Test coverage:
- EventStored published after successful SaveEvent
- No EventStored published on version conflict
- Multiple EventStored events published in order
- SaveEvent works correctly without broadcaster (nil-safe)
Closes#61
Co-Authored-By: Claude Code <noreply@anthropic.com>
- Add Metadata field (map[string]string) to Event struct with omitempty
- Add helper methods for common metadata: SetCorrelationID/GetCorrelationID,
SetCausationID/GetCausationID, SetUserID/GetUserID, SetTraceID/GetTraceID,
SetSpanID/GetSpanID
- Add WithMetadataFrom helper for copying metadata between events
- Add metadata key constants for standard fields
- Add comprehensive unit tests for metadata serialization and helpers
- Add store tests verifying metadata persistence
Closes#7
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Add ErrVersionConflict error type and VersionConflictError for detailed
conflict information
- Implement version validation in InMemoryEventStore.SaveEvent that rejects
events with version <= current latest version
- Implement version validation in JetStreamEventStore.SaveEvent with version
caching for performance
- Add comprehensive tests for version conflict detection including concurrent
writes to same actor
- Document versioning semantics in EventStore interface and CLAUDE.md
This ensures events have monotonically increasing versions per actor and
provides clear error messages for version conflicts, enabling optimistic
concurrency control patterns.
Closes#6
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Test SaveEvent persists events correctly (single, multiple, multi-actor)
- Test GetEvents retrieves events in insertion order
- Test GetEvents with fromVersion filtering
- Test GetLatestVersion returns correct version
- Test behavior with non-existent actor IDs (returns empty/zero)
- Test concurrent access safety with race detector
- Add mutex protection to InMemoryEventStore for thread safety
Closes#3
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
