自托管SignalR2多层依赖注入

时间:2018-01-21 18:12:19

标签: c# dll console-application ninject signalr-2

我刚刚使用Ninject为我的自托管SignalR2项目实施了DI。

public class NinjectSignalRDependencyResolver : DefaultDependencyResolver
{
    private readonly IKernel _kernel;
    public NinjectSignalRDependencyResolver(IKernel kernel)
    {
        _kernel = kernel;
    }

    public override object GetService(Type serviceType)
    {
        return _kernel.TryGet(serviceType) ?? base.GetService(serviceType);
    }

    public override IEnumerable<object> GetServices(Type serviceType)
    {
        return _kernel.GetAll(serviceType).Concat(base.GetServices(serviceType));
    }
}

我的启动课程:

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        app.UseCors(CorsOptions.AllowAll);

        var kernel = new StandardKernel();
        var resolver = new NinjectSignalRDependencyResolver(kernel);

        kernel.Bind<MyDbContext>().ToSelf();

        kernel.Bind<IRealTimeDataEngine>().To<RealTimeDataEngine>().InSingletonScope();
        kernel.Bind<IHistoricalDataEngine>().To<HistoricalDataEngine>().InSingletonScope();

        kernel.Bind(typeof(IHubConnectionContext<dynamic>)).ToMethod(context =>
            resolver.Resolve<IConnectionManager>().GetHubContext<MyHub>().Clients
        ).WhenInjectedInto<IRealTimeDataEngine>();

        var config = new HubConfiguration {Resolver = resolver};
        ConfigureSignalR(app, config);
    }

    public static void ConfigureSignalR(IAppBuilder app, HubConfiguration config)
    {
        app.MapSignalR(config);
    }
}

在我的信号器中心构造函数中,我期待一个IRealTimeDataEngine。

public MyHub(IRealTimeDataEngine realTimeDataEngine, IHistoricalDataEngine historicalDataEngine)

在我的主机(一个控制台应用程序)中,我需要注入相同的IRealTimeDataEngine。

public DummyProvider(IRealTimeDataEngine realTimeDataEngine)

在我的Main方法中,我需要创建一个DummyProvider对象。

如果我没弄错,创建一个新内核不会在两个不同的项目中给我相同的对象,那么我应该如何在我的作文根处要求相同的IRealTimeDataEngine?

1 个答案:

答案 0 :(得分:1)

你是对的,每个应用程序必须只使用一个内核。这意味着您应该在Startup类之外创建内核。这可以通过使用WebApp.Start方法的重载调用来实现,如:

class Program
{
    static void Main(string[] args)
    {
       var kernel = new StandardKernel();

       var server = WebApp.Start("http://localhost:8080/", (appBuilder) =>
       {
           var resolver = new NinjectSignalRDependencyResolver(kernel);
           var config = new HubConfiguration {Resolver = resolver};
           ...
       });

       ...