Interface IForgetsDeletedTenants
- Namespace
- Stratara.Projections.Abstractions
- Assembly
- Stratara.Projections.dll
A projection that forgets a tenant once the tenant is deleted. The framework hands it the
tenant-deletion facts it ships — TenantDeleted and CustomerTenantsDeleted — whether or
not the projection handles them, and after each one records, for this projection alone, the tenants
it deleted. When the projection later throws
PrecedingFactMissingException for a fact owned by
such a tenant, the fact is passed over and logged instead of being retried and failing.
public interface IForgetsDeletedTenants : IProjection- Extension Methods
Remarks
Declaring it is a promise: once either deletion fact has been applied, the tenant's data is gone from
this projection's read model — removed by the projection's own handlers or by anything else. A fact
recorded for that tenant after the deletion — work that was queued before it and ran to its end —
then finds nothing to apply to, and would otherwise dead-letter live and fail every replay. Removing
the data stays the projection's own job; the framework only remembers that it happened. A projection
that keeps a tenant's rows after TenantDeleted, the tenant's soft delete, must not declare it:
a genuine "not applied yet" for that tenant would be passed over for good.
Only the outcome of a missing-prerequisite report changes. A fact of a deleted tenant that the projection applies without complaint is applied, and a report for any other tenant is retried and fails as before. The record is kept by the registered IForgottenTenantStore; a declaring projection in a host without one fails on the first fact it is handed. A replay empties the record of each declaring projection it rebuilds just before the read models, and a projection rebuilt on its own on the Orleans execution model has its record emptied just before its read model.