endpoint routing 闪亮登场，以下代码来自 https://github.com/aspnet/AspNetCore/issues/7795

// This helper method comes in 3.0. For now you'll need a copy in your app
public static Endpoint GetEndpoint(HttpContext context)
{
    if (context == null)
    {
       throw new ArgumentNullException(nameof(context));
    }

    return context.Features.Get<IEndpointFeature>()?.Endpoint;
}

var endpoint = GetEndpoint(context);

// Endpoint will be null if the URL didn't match an action, e.g. a 404 response
if (endpoint != null)
{
    var yourAttribute = endpoint.Metadata.GetMetadata<YourAttributeOnTheMvcAction>();
}