（四）MMA（事件通知/模块间数据状态迁移/Meterialized Views/Saga Pattern）

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项目地址

• 教程作者：
• 教程地址：

• 代码仓库地址：

• 所用到的框架和插件：

dbt 
airflow

一、事件通知

二、数据状态迁移

• 模块下的IntegrationEvents这个模块是专门用来负责数据状态迁移，一般是用来，同步到CRM系统或是邮件系统

2.1 UserRegisteredIntegrationEvent

1. 创建UserRegisteredIntegrationEvent（Users）

• 这个类是用来定义该行为的对象

namespace Evently.Modules.Users.IntegrationEvents;
public sealed class UserRegisteredIntegrationEvent
 : IntegrationEvent
{
   
    public UserRegisteredIntegrationEvent(
        Guid id,
        DateTime occurredOnUtc,
        Guid userId,
        string email,
        string firstName,
        string lastName)
        : base(id, occurredOnUtc)
    {
   
        UserId = userId;
        Email = email;
        FirstName = firstName;
        LastName = lastName;
    }
    public Guid UserId {
    get; init; }
    public string Email {
    get; init; }
    public string FirstName {
    get; init; }
    public string LastName {
    get; init; }
}

2. UserRegisteredIntegrationEvent进行发布(Users)

• 这里发布的是上面的UserRegisteredIntegrationEvent
  

3. UserRegisteredIntegrationEventHandler（消费者模块）

• 所有需要用到该数据的模块，都需要创建UserRegisteredIntegrationEventHandler，该系统中Ticketing和

namespace Evently.Modules.Ticketing.Presentation.Customers;
internal sealed class UserRegisteredIntegrationEventHandler(ISender sender)
    : IntegrationEventHandler<UserRegisteredIntegrationEvent>
{
   
    public override async Task Handle(
        UserRegisteredIntegrationEvent integrationEvent,
        CancellationToken cancellationToken = default)
    {
   
        Result result = await sender.Send(
            new CreateCustomerCommand(
                integrationEvent.UserId,
                integrationEvent.Email,
                integrationEvent.FirstName,
                integrationEvent.LastName),
            cancellationToken);
        if (result.IsFailure)
        {
   
            throw new EventlyException(nameof(CreateCustomerCommand), result.Error);
        }
    }
}

• Attendance 模块

namespace Evently.Modules.Attendance.Presentation.Attendees;
internal sealed class UserRegisteredIntegrationEventHandler(ISender sender)
    : IntegrationEventHandler<UserRegisteredIntegrationEvent