IApplicationLifetime ApplicationStopping does not trigger if ConfigureServices method exists

[davidfowl]

I spent a good few hours trying to track this down on mono and it seems like it happens on windows as well.

using System;
using Microsoft.AspNet.Http;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Hosting;
using Microsoft.Framework.DependencyInjection;

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {

    }

    public void Configure(IApplicationBuilder app, IApplicationLifetime lifetime)
    {
        lifetime.ApplicationStopping.Register(OnStuff);
    }

    public void OnStuff()
    {
        Console.WriteLine("Goodbye!");
    }
}

The above code will not print out goodbye.

[davidfowl]

/cc @Praburaj @Tratcher

[Praburaj]

Related: aspnet/HttpSysServer#71

[davidfowl]

Is it? It happens when use kestrel. Seems like a bug in hosting

[Tragetaschen]

On Mono, Kestrel throws an Exception during its Dispose (aspnet/KestrelHttpServer#49). This means the cleanup code in HostingEngine.Start's Disposable does not invoke applicationLifetime.SignalStopped()

[davidfowl]

I'm not sure that's even related, when you remove ConfigureServices, the text "Goodbye!" gets printed

[davidfowl]

Here's my workaround:

using System;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Hosting;
using Microsoft.Framework.DependencyInjection;

namespace WebApplication52
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services, IApplicationLifetime lifetime)
        {
            services.AddInstance(lifetime);
        }

        public void Configure(IApplicationBuilder app, IApplicationLifetime lifetime)
        {
            lifetime.ApplicationStopping.Register(OnStuff);
        }

        public void OnStuff()
        {
            Console.WriteLine("Goodbye!");
        }
    }
}

[Praburaj]

okay. Actually these are all problems related to app shutdown .

[davidfowl]

This is specifically related to the fact that something is going bonkers when services are applied. I don't think this has to do with app shutdown per se as everything is functioning. It feels like its triggering the event on some bogus ApplicationLifetime service, rather than the one I'm using. Which is why the above code seems to work.

[Praburaj]

Looks like the case. I can see a difference in the ApplicationStopping cancellation token that I receive in ConfigureServices vs Configure. If ConfigureServices is present then hosting additionally does a services.BuildServiceProvider(). I'm investigating this more.