如何在.NetCore 2.2中从StartUp注入2个EventHubClient

Question

我将EventHubClient注入到我的控制器中，如下所示

services.AddScoped<EventHubClient>(a =>
     {
        eventHubClientIncomplete = EventHubClient.CreateFromConnectionString(new EventHubsConnectionStringBuilder(eventHubSettingsIncompleteApplications.ConnectionString)
        {
           EntityPath = eventHubSettingsIncompleteApplications.EventHubName
        }.ToString());
        return eventHubClientIncomplete;
     });

它运行良好。但是现在我需要从不同的端点发送到多个EventHubs。我该怎么做that...any指针？

Answer 1

我想到了3个解决方案：

1.为EventHubClient创建自己的工厂。然后在服务中添加工厂。通过这种方式，您将能够在需要时注入工厂实例，然后从工厂方法中获取所需的EventHubClient。

2.使用其他DI引擎。例如: Unity Container，使用它可以获得如下服务：container.Resolve<IService>(key)

3.创建一个保存EventHubClient的类。

    public class EventHubClientHolder
    {
        public string Name;
        public EventHubClient eventHubClient;
    }

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllersWithViews();
        services.AddSingleton<EventHubClientHolder>(_ => { return new EventHubClientHolder() { Name = "A", eventHubClient = ..... }; });
        services.AddSingleton<EventHubClientHolder>(_ => { return new EventHubClientHolder() { Name = "B", eventHubClient = ..... }; });
    }

    public HomeController(ILogger<HomeController> logger, IEnumerable<EventHubClientHolder> services)
    {
        _logger = logger;
        _services = services;
    }

    public IActionResult Index()
    {
        var eventHubClient = _services.First(_ => _.Name.Equals("A"))).eventHubClient;
        return View();
    }