c# - 将 SignalR 的 ITransportHeartbeat 添加到 Autofac

Question

我正在尝试使用 Autofac 来拥有 ITransportHeartbeat 的一个实例我的 ASP.NET MVC 5 应用程序的接口(interface)，用于跟踪所有连接的用户。我使用 ITransportHeartbeat接口(interface)来确定用户的连接是否仍然处于事件状态。为此，我需要使用 Autofac 为应用程序创建一个 SignalR 集线器实例。

挑战:当我运行应用程序时，它永远不会遇到被覆盖的 OnConnected() , OnReconnected() , 或 OnDisconnected()在 SignalR 集线器中。但是，客户的hub.start()被击中，我看到 Hub Started页面加载时的消息:

$.connection.hub.start().done(function () {
    console.log("Hub Started");
});

如果我向集线器添加一个无参数构造函数，它确实会命中它们，但随后会出现 ITransportHeartbeat interface 为空，这违背了将接口(interface)注入(inject)集线器的目的。

我引用了以下内容以寻求帮助:

https://stackoverflow.com/a/49214891/177416

https://autofaccn.readthedocs.io/en/latest/integration/signalr.html

https://stackoverflow.com/a/36476106/177416

https://stackoverflow.com/a/21126852/177416

这里是 Startup.cs :

public partial class Startup
{
    public void Configuration(IAppBuilder app)
    {
        ConfigureAuth(app);

        var builder = new ContainerBuilder();
        var config = GlobalConfiguration.Configuration;

        builder.RegisterControllers(typeof(MvcApplication).Assembly)
            .InstancePerRequest();
        builder.RegisterApiControllers(Assembly.GetExecutingAssembly())
            .InstancePerRequest();

        var signalRConfig = new HubConfiguration();
        builder.RegisterType<MonitoringHubBase>().ExternallyOwned();

        builder.RegisterType<Autofac.Integration.SignalR.AutofacDependencyResolver>()
            .As<Microsoft.AspNet.SignalR.IDependencyResolver>()
            .SingleInstance();
        builder.Register(context => 
            context.Resolve<Microsoft.AspNet.SignalR.IDependencyResolver>()
            .Resolve<IConnectionManager>()
            .GetHubContext<MonitoringHubBase, IMonitoringHubBase>())
            .ExternallyOwned();
        builder.RegisterType<Microsoft.AspNet.SignalR.Transports.TransportHeartbeat>()
            .As<Microsoft.AspNet.SignalR.Transports.ITransportHeartbeat>()
            .SingleInstance();

        var container = builder.Build();
        DependencyResolver.SetResolver(
            new Autofac.Integration.Mvc.AutofacDependencyResolver(container));

        signalRConfig.Resolver = container
            .Resolve<Microsoft.AspNet.SignalR.IDependencyResolver>();

        app.UseAutofacMiddleware(container);
        app.MapSignalR("/signalr", signalRConfig);

        config.DependencyResolver = 
            new AutofacWebApiDependencyResolver((IContainer)container);

        AreaRegistration.RegisterAllAreas();
        GlobalConfiguration.Configure(WebApiConfig.Register);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
        BundleConfig.RegisterBundles(BundleTable.Bundles);
    }
}

这是其他集线器从中派生的集线器:

public interface IMonitoringHubBase
{
    Task OnConnected();
    Task OnReconnected();
    Task OnDisconnected(bool stopCalled);
}

public abstract class MonitoringHubBase : Hub<IMonitoringHubBase>
{
    private ITransportHeartbeat Heartbeat { get; }

    public MonitoringHubBase(ITransportHeartbeat heartbeat)
    {
        Heartbeat = heartbeat;
    }

    public MonitoringHubBase()
    {
    }

    public override async Task OnConnected()
    {
        // Add connection to db...
    }

    public override async Task OnReconnected()
    {
        // Ensure connection is on db...
    }

    public override async Task OnDisconnected(bool stopCalled)
    {
        // Remove connection from db...
    }

    public async Task SomeMethod(int id)
    {
        // Heartbeat object used here...
    }
}

这是从基础集线器继承的集线器之一:

[HubName("MyHub")]
public class MyHub : MonitoringHubBase
{
    public MyHub(ITransportHeartbeat heartbeat) : base(heartbeat)
    {
    }

    public MyHub()
    {   
    }
}

Answer 1

找到了解决方案!从集线器中删除了无参数 c'tor 并修改了 Startup.cs对此；希望这可以帮助下一个为此苦苦挣扎的人:

public partial class Startup
{
    public void Configuration(IAppBuilder app)
    {
        ConfigureAuth(app);

        var builder = new ContainerBuilder();
        var config = new HttpConfiguration();

        builder.RegisterHubs(Assembly.GetExecutingAssembly());
        builder.RegisterControllers(typeof(MvcApplication).Assembly)
            .InstancePerRequest();
        builder.RegisterApiControllers(Assembly.GetExecutingAssembly())
            .InstancePerRequest();
        builder.RegisterType<Microsoft.AspNet.SignalR.Transports.TransportHeartbeat>()
            .As<Microsoft.AspNet.SignalR.Transports.ITransportHeartbeat>()
            .SingleInstance();
        builder.RegisterType<Autofac.Integration.SignalR.AutofacDependencyResolver>()
            .As<Microsoft.AspNet.SignalR.IDependencyResolver>()
            .SingleInstance();

        var container = builder.Build();

        var signalRConfig = new HubConfiguration();
        signalRConfig.Resolver = new Autofac.Integration.SignalR.AutofacDependencyResolver(container);

        app.UseAutofacMiddleware(container);

        DependencyResolver.SetResolver(new Autofac.Integration.Mvc.AutofacDependencyResolver(container));

        app.Map("/signalr", map =>
        {
            map.UseAutofacMiddleware(container);

            var hubConfiguration = new HubConfiguration
            {
                Resolver = new Autofac.Integration.SignalR.AutofacDependencyResolver(container),
            };

            map.RunSignalR(hubConfiguration);
        });

        config.DependencyResolver = new AutofacWebApiDependencyResolver((IContainer)container);

        AreaRegistration.RegisterAllAreas();
        GlobalConfiguration.Configure(WebApiConfig.Register);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
        BundleConfig.RegisterBundles(BundleTable.Bundles);
    }
}

在这篇文章的帮助下: https://kwilson.io/blog/get-your-web-api-playing-nicely-with-signalr-on-owin-with-autofac/