Part of Automated Products.
Product declares three events by attribute — [RaisesEvent] only declares and raises; nothing in this feature calls AddEvent by hand. DKNet’s EF Core save hook reads the declarations and raises each event after a successful SaveChanges, driven by change-tracker state.
| Event | Raised when | Payload | Transport | Consumers | Ordering | Duplicates | On failure |
|---|---|---|---|---|---|---|---|
ProductCreatedEvent |
A product is inserted — including the replacement Discontinue() creates |
Id, Name, Price (narrowed by Include = [...] on the attribute) |
In-memory bus (always) + Azure Service Bus topic product-tp (only when EnableServiceBus is true) |
ProductCreatedEventHandler (in-memory, logs only) and, on the Azure child bus, ProductCreatedNotificationHandler (logs only) |
None | None observed — both handlers only log; neither is idempotent-by-design because neither writes state | See below |
ProductPriceUpdatedEvent |
ChangePrice saves |
Every audited property (Id, Name, Price, IsDiscontinued, OwnedBy, CreatedBy, CreatedOn, UpdatedBy, UpdatedOn, SupplierCostPrice, SupplierReferenceCode, LastModifiedBy, LastModifiedOn) — the attribute names only Price to compose the event’s name, not to narrow its payload |
In-memory bus only | None — no handler is registered for it in this repository | None | — | — |
ProductIsDiscontinuedUpdatedEvent |
Discontinue() saves |
Same full payload shape as ProductPriceUpdatedEvent above |
In-memory bus only | None — no handler is registered for it in this repository | None | — | — |
Event type names are composed by convention — <Entity><NarrowingProps><Operation>Event — and payload shapes are confirmed against the compiled assembly’s XML documentation (Minimal.Domains.xml), since none has a hand-written source file.
On failure. AddMemoryBus sets EnableBlockingPublish = false; whether that specifically means a handler exception there is swallowed rather than surfaced to the caller’s request is not confirmed from this repository alone — see ❓ Open questions on index.md. The handler runs in-process either way. For the Azure path: ServiceBusSetup.AddAzureBus sets TopologyProvisioning.Enabled = false, so the product-tp topic and product-sub subscription must already exist — this code does not create them. The MaxDeliveryCount: 10, dead-lettering and 7-day TTL settings in CreateSubscriptionOptions only take effect on a subscription this code provisions, which, with provisioning off, it does not; whether the pre-existing subscription honors matching settings is outside this repository. An event raised while EnableServiceBus is false (Development’s setting) is never produced to Azure at all — only the in-memory handler runs, and there is no retained or replayed copy for when the flag turns on later. Whether a database commit with no subsequent publish (a crash between the two, with no outbox pattern in this code) can drop an event entirely is tracked as an open question on index.md.
| System | Direction | How | What for | When it is down |
|---|---|---|---|---|
Azure Service Bus (product-tp topic / product-sub subscription) |
we call it (produce) + it calls us (consume) | azb.Produce<ProductCreatedEvent>/azb.Consume<ProductCreatedEvent> in ServiceBusSetup.AddAzureBus, wired only when FeatureManagement:EnableServiceBus is true and ConnectionStrings:AzureBus is non-empty |
Notifies an external subscriber that a product was created | Registered, unused in Development: EnableServiceBus is false in appsettings.Development.json, so the Azure child bus is never added and ProductCreatedNotificationHandler never runs. In appsettings.json (the non-Development default) it is true; this repository sets no client-side retry or circuit breaker around the SDK call. Whether POST / still answers 201 when the topic is unreachable is open — see ❓ Open questions on index.md. |
PostgreSQL (sample.Products) is this feature’s only other dependency, and it is the request’s own data store rather than a downstream integration — see Data model.
The create-to-event path, including the Azure branch, is drawn in index.md. That diagram cannot show ProductPriceUpdatedEvent or ProductIsDiscontinuedUpdatedEvent: both are raised the same way on their respective saves, but this repository registers no consumer for either, so there is no second hop to draw.