DomainEventDispatcherExtensions Class

Definition

Namespace

Savvyio.Domain

Assemblies

Savvyio.Domain.dll

Source

src/Savvyio.Domain/DomainEventDispatcherExtensions.cs

Extension methods for the IDomainEventDispatcher interface.

public static class DomainEventDispatcherExtensions

Inheritance

object

DomainEventDispatcherExtensions

Examples

This example shows how to flush the pending events collected by an aggregate through IDomainEventDispatcher. The sample raises one batch synchronously and a second batch asynchronously so both RaiseMany and RaiseManyAsync are exercised in the workflow that clears the aggregate event list.

using System.Collections.Generic;
using System.Threading.Tasks;
using Savvyio;
using Savvyio.Dispatchers;
using Savvyio.Domain;
using Savvyio.Handlers;

namespace ExampleApp;

public sealed class DomainEventDispatcherExtensionsExample
{
    public async Task<(bool SyncCleared, bool AsyncCleared)> RaisePendingEventsAsync()
    {
        var dispatcher = new DomainEventDispatcher(new ServiceLocator(serviceType => serviceType == typeof(IDomainEventHandler) ? new object[] { new AccountOpenedHandler() } : []));

        var syncAggregate = new AccountAggregate();
        syncAggregate.Record(new AccountOpenedEvent("ACC-42"));
        dispatcher.RaiseMany(syncAggregate);

        var asyncAggregate = new AccountAggregate();
        asyncAggregate.Record(new AccountOpenedEvent("ACC-43"));
        await dispatcher.RaiseManyAsync(asyncAggregate).ConfigureAwait(false);

        return (syncAggregate.Events.Count == 0, asyncAggregate.Events.Count == 0);
    }
}

public sealed class AccountAggregate : IAggregateRoot<AccountOpenedEvent>
{
    private readonly List<AccountOpenedEvent> _events = new();
    public IMetadataDictionary Metadata { get; } = new MetadataDictionary();
    public IReadOnlyList<AccountOpenedEvent> Events => _events;
    public void Record(AccountOpenedEvent e) => _events.Add(e);
    public void RemoveAllEvents() => _events.Clear();
}

public sealed class AccountOpenedHandler : IDomainEventHandler
{
    public IFireForgetActivator<IDomainEvent> Delegates => HandlerFactory.CreateFireForget<IDomainEvent>(registry => registry.Register<AccountOpenedEvent>(_ => { }));
}

public sealed record AccountOpenedEvent(string AccountId) : Request, IDomainEvent;

Methods

Name	Description
RaiseManyAsync<T>(IDomainEventDispatcher, IAggregateRoot<T>, Action<AsyncOptions>)	Asynchronously raises domain events from the specified aggregate to handlers that implements the IDomainEventHandler interface.
RaiseMany<T>(IDomainEventDispatcher, IAggregateRoot<T>)	Raises domain events from the specified aggregate to handlers that implements the IDomainEventHandler interface.