模拟 ApiController SignalR 广播

Question

我正在尝试模拟 ApiController(WebApi) 中存在的 SignalR 广播，但无法完成测试用例，下面是我的代码

信号RHub

public class HubServer : Hub { }

ApiControllerWithHub

public abstract class ApiControllerWithHubController<THub> : ApiController where THub : IHub
{
    Lazy<IHubContext> hub = new Lazy<IHubContext>(() => GlobalHost.ConnectionManager.GetHubContext<THub>());

    protected IHubContext Hub
    {
        get { return hub.Value; }
    }
}

控制器（模拟方法）

public class NotificationController : ApiControllerWithHubController<HubServer>
{
    [HttpPost]
    public HttpResponseMessage SendNotification(NotificationInput notification)
    {
        Hub.Clients.Group("GroupName").BroadcastCustomerGreeting("notification");
    }
}

我正在 Mock SignalR Post 的帮助下编写以下单元测试，我被困在这里，因为这是来自控制器而不是来自 SignalR Hub 的 SignalR 调用。

模拟测试

public interface IClientContract
{
    void BroadcastCustomerGreeting(string message);
}

[TestMethod]
public void SendNotificationTest()
{
    NotificationInput notificationInput = new NotificationInput();
    notificationInput.CId = "CUST001";
    notificationInput.CName = "Toney";

    // Arrange
    var mockClients = new Mock<IHubConnectionContext<dynamic>>();
    var mockGroups = new Mock<IClientContract>();

    // Act.
    mockGroups.Setup(_ => _.BroadcastCustomerGreeting("notification")).Verifiable();
    mockClients.Setup(_ => _.Group("GroupName")).Returns(mockGroups.Object);

    // I'm stuck here
    var controller = new NotificationController();

    // Act
    HttpResponseMessage actionResult = controller.SendNotification(notificationInput);
}

感谢任何帮助以完成/更正此单元测试。

Answer 1

需要重新设计。基础ApiController 与集线器上下文的静态访问器紧密耦合。这需要重构为自己的服务，以便通过构造函数注入提供更大的灵活性。

public interface IHubContextProvider {
    IHubContext Hub { get; }
}

public class HubContextProvider<THub> : IHubContextProvider where THub : IHub {
    Lazy<IHubContext> hub = new Lazy<IHubContext>(() => GlobalHost.ConnectionManager.GetHubContext<THub>());
    public IHubContext Hub {
        get { return hub.Value; }
    }
}

现在需要重构控制器以显式公开其依赖项。

public abstract class ApiControllerWithHubController<THub> : ApiController where THub : IHub {

    private readonly IHubContext hub;

    public ApiControllerWithHubController(IHubContextProvider context) {
        this.hub = context.Hub;
    }

    protected IHubContext Hub {
        get { return hub; }
    }
}


public class NotificationController : ApiControllerWithHubController<HubServer> {

    public NotificationController(IHubContextProvider context)
        : base(context) {

    }

    [HttpPost]
    public IHttpActionResult SendNotification(NotificationInput notification) {
        Hub.Clients.Group("GroupName").BroadcastCustomerGreeting("notification");
        return Ok();
    }
}

现在可以使用必要的依赖模拟来进行测试。

[TestMethod]
public void _SendNotificationTest() {

    // Arrange
    var notificationInput = new NotificationInput();
    notificationInput.CId = "CUST001";
    notificationInput.CName = "Toney";
    var groupName = "GroupName";
    var message = "notification";

    var mockGroups = new Mock<IClientContract>();
    mockGroups.Setup(_ => _.BroadcastCustomerGreeting(message)).Verifiable();

    var mockClients = new Mock<IHubConnectionContext<dynamic>>();
    mockClients.Setup(_ => _.Group(groupName)).Returns(mockGroups.Object).Verifiable();

    var mockHub = new Mock<IHubContext>();
    mockHub.Setup(_ => _.Clients).Returns(mockClients.Object).Verifiable();

    var mockHubProvider = new Mock<IHubContextProvider>();
    mockHubProvider.Setup(_ => _.Hub).Returns(mockHub.Object);

    var controller = new NotificationController(mockHubProvider.Object);

    // Act
    var actionResult = controller.SendNotification(notificationInput);

    //Assert
    mockClients.Verify();
    mockGroups.Verify();
    mockHub.Verify();
}

只需确保向 DI 容器注册新服务，以便可以将其注入到依赖的控制器中。

通过重新设计，可以将基本控制器一起移除，直接使用集线器提供程序。这是假设没有任何其他理由拥有基本控制器。