eQuantic.Core.DomainEvents

Domain Events implementation for DDD (Domain-Driven Design) in .NET.

Installation

dotnet add package eQuantic.Core.DomainEvents

Features

• IDomainEvent - Base interface for domain events (extends IEvent from Core.Eventing)
• DomainEventBase - Base class for domain events with automatic EventId and OccurredAt
• IAggregateRoot<TKey> - Interface for aggregate roots with event sourcing
• AggregateRoot<TKey> - Base class for aggregate roots with domain event support
• IDomainEventHandler<T> - Handler interface for domain events
• IDomainEventDispatcher - Dispatcher for domain events

Usage

Define a Domain Event

public class OrderPlacedEvent : DomainEventBase { public Guid OrderId { get; } public decimal TotalAmount { get; } public OrderPlacedEvent(Guid orderId, decimal totalAmount) { OrderId = orderId; TotalAmount = totalAmount; } }

Create an Aggregate Root

public class Order : AggregateRoot { public override Guid Id { get; protected set; } public decimal TotalAmount { get; private set; } public bool IsPlaced { get; private set; } public void Place(decimal amount) { TotalAmount = amount; IsPlaced = true; // Raise domain event RaiseDomainEvent(new OrderPlacedEvent(Id, amount)); } }

Handle Domain Events

public class OrderPlacedHandler : IDomainEventHandler<OrderPlacedEvent> { public async Task HandleAsync(OrderPlacedEvent @event, CancellationToken ct) { Console.WriteLine($"Order {@event.OrderId} placed for ${@event.TotalAmount}"); } }

Register Services

services.AddDomainEvents(); services.AddDomainEventHandler<OrderPlacedEvent, OrderPlacedHandler>();

Dispatch Events

public class OrderRepository : IOrderRepository { private readonly IDomainEventDispatcher _dispatcher; public async Task SaveAsync(Order order, CancellationToken ct) { // Save to database... // Dispatch domain events await _dispatcher.DispatchEventsAsync(order, ct); } }

Integration with eQuantic Ecosystem

This package integrates with:

• eQuantic.Core.Eventing - Shared IEvent interface
• eQuantic.Core.CQS - INotification also extends IEvent

License

MIT License - See LICENSE for details.