基于MassTransit的测试活动补偿

Question

我试图在我的活动中测试补偿逻辑，但我不知道如何在测试中启动Compensate方法。如果在DB中找不到什么东西，我有一个活动应该抛出一个异常。在这种情况下，我已经想出了如何确保故障中的活动，但我找不出补偿部分。

我的考试课在下面。注意，等待RoutingSlipActivityCompensated处理程序会抛出一个TaskCanceledException。如何测试活动的补偿部分？

[TestClass]
public class DisableTeamCheckInsActivityTests
{
   Mock<ILogger<DisableTeamCheckInsActivity>> _logger;
   CheckInsDbContext _db;

   InMemoryTestHarness _harness;
   ActivityTestHarness<DisableTeamCheckInsActivity, DisableTeamCheckIns, DisableTeamCheckInsLog> _activity;

   [TestInitialize]
   public async Task Initialize()
   {
      _logger = new Mock<ILogger<DisableTeamCheckInsActivity>>();
      _db = CheckInDbContextFactory.Create();

      _harness = new InMemoryTestHarness
      {
         TestTimeout = TimeSpan.FromSeconds(5)
      };

      _activity = _harness.Activity<DisableTeamCheckInsActivity, DisableTeamCheckIns, DisableTeamCheckInsLog>(
         _ => new DisableTeamCheckInsActivity(_logger.Object, _db),
         _ => new DisableTeamCheckInsActivity(_logger.Object, _db)
      );

      await _db.Database.EnsureCreatedAsync();
      await _harness.Start();
   }

   [TestCleanup]
   public async Task Cleanup()
   {
      await _db.Database.EnsureDeletedAsync();
      await _harness.Stop();
   }

   [TestMethod]
   public async Task Missing_Team_Throws()
   {
      var teamId = Guid.NewGuid();

      var builder = new RoutingSlipBuilder(Guid.NewGuid());
      builder.AddSubscription(_harness.BusAddress, RoutingSlipEvents.All);

      var faulted = _harness.SubscribeHandler<RoutingSlipActivityFaulted>();
      var compensated = _harness.SubscribeHandler<RoutingSlipActivityCompensated>();

      builder.AddActivity(_activity.Name, _activity.ExecuteAddress, new
      {
         TeamId = teamId
      });

      await _harness.Bus.Execute(builder.Build());

      var faultContext = await faulted;
      Assert.AreEqual("System.InvalidOperationException", faultContext?.Message?.ExceptionInfo?.ExceptionType);

      await compensated; // <-- This throws a TaskCanceledException
   }
}

Answer 1

一个单一活动的路由选择将永远无法弥补。如果是活动故障，则是路由滑动故障，但是由于没有任何以前的活动，所以在路由选择中没有任何补偿信息。

如果活动完成，而随后的活动出现故障，则将调用compensate方法，并发布ActivityCompensated事件。