Skip to main content

Asset Event Idempotency

Summary​

Asset event delivery is at-least-once by design; a failed publish is retried and may result in a duplicate. Producer-side deduplication does not exist. A foundation ProcessedIntegrationEvent ledger exists for future inbound consumption but is not yet used.

Audience​

Engineering, integration, QA, architecture, security, and product reviewers.

Reference Content​

Delivery semantics​

ConcernVerified behavior
Delivery intentAt-least-once (failed rows retried)
Producer deduplicationNone
Event identityEventId (GUID) per contract, also on the outbox row
Inbound idempotency ledger in asset-serviceProcessedIntegrationEvent (exists, unused)
Consumer duplicate handlingOwned by Notification (keys on event identity)

Producer side​

The outbox processor re-fetches rows whose status is Pending or Failed. A row that failed to publish is retried on the next pass. There is no producer-side check that the same EventId was already delivered; if a broker acknowledged a publish that the processor recorded as failed, a duplicate could be produced. Consumers are therefore expected to be idempotent.

Asset-service inbound ledger (foundation)​

ProcessedIntegrationEvent records one row per consumed integration EventId, with EventType, TenantId, CorrelationId, SourceService, Outcome, and ProcessedOnUtc. Its source comment states it is "for when this service subscribes." No inbound consumer writes to it in the verified source, so it is a Foundation structure, not active idempotency.

Consumer side (Notification)​

The notification consumer keys each delivery on its event identity and dispatches within a scope; duplicate suppression and delivery retry are owned by the Notification module and documented there. Asset events use that same path.

Requires confirmation​

Whether a consumer other than Notification will require the asset-service inbound ledger, and the exactly-once expectations for downstream consumers, require confirmation.

Source References​

  • microservices/src/asset-service/Infrastructure/AssetDbContext.cs
  • microservices/src/shared-kernel/Messaging/OutboxProcessor.cs
  • microservices/src/notification-service/Messaging/NotificationEventConsumer.cs

See Also​

Keywords​

  • Idempotency
  • At-least-once
  • Processed integration event

Revision Information​

  • Status: Draft
  • Last reviewed: 2026-07-17
  • Review cycle: Quarterly