dubbo-admin-events

# dubbo-admin Events ## Purpose Use this skill to modify or explain the shared EventBus contract used by discovery, engine, informers, and subscribers. ## When to use Use for EventBus interfaces, resource-kind dispatching, subscriber registration uniqueness, synchronous processing, and event dispatch error behavior. Do not use for business logic inside a single subscriber unless EventBus semantics change. ## Inputs Required: - EventBus behavior, interface, or dispatch problem. - Event producer or subscriber involved. Optional: - Event type. - Old and new resource objects. - Subscriber names for the same resource kind. If missing, inspect `pkg/core/events/eventbus.go` and `pkg/core/events/component.go` first. ## Workflow 1. Read `pkg/core/events/eventbus.go` for Event, Emitter, Subscriber, SubscriptionManager, and EventBus interfaces. 2. Read `pkg/core/events/component.go` for the concrete EventBus implementation. 3. Trace producers that call `events.NewResourceChangedEvent` and `Emitter.Send`. 4. Trace consumers implementing `ResourceKind`, `Name`, and `ProcessEvent`. 5. Read `references/eventbus-dispatch.md` before changing dispatch semantics. ## Output format Return event source, resource kind, subscribers called, error behavior, changed files, and validation evidence. ## Validation - Confirm `Send` uses `NewObj()` first and `OldObj()` for delete-like events. - Confirm subscriber names are unique per resource kind. - Confirm subscriber errors are logged and do not stop later subscribers. - Run tests or targeted reasoning for discovery and engine consumers when dispatch changes. ## Edge cases - Events with both old and new nil cannot be routed. - Dispatch is synchronous; long subscriber work blocks the caller. - EventBus should stay domain-neutral; put business logic in subscribers. ## References - Read `references/eventbus-dispatch.md` for concrete dispatch rules and failure behavior.