Implementing Domain-Driven Design

Implementing Eventual Consistency

It looks as if there could be a legitimate use of eventual consistency between separate Aggregates. Here is how it could work.

When a Task processes an estimateHoursRemaining() command, it publishes a corresponding Domain Event. It does that already, but the team would now leverage the Event to achieve eventual consistency. The Event is modeled with the following properties:

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public class TaskHoursRemainingEstimated implements DomainEvent {     private Date occurredOn;     private TenantId tenantId;     private BacklogItemId backlogItemId;     private TaskId taskId;     private int hoursRemaining;     ... }

A specialized subscriber would now listen for these and delegate to a ...