Deadlock when using Autofac and the ConsoleLifetime on exit

I’m trying to use Autofac as my service provider in a console application. Here is a minimal program to repro this:

using System.Threading.Tasks;
using Autofac.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

public class Program
{
    public static async Task Main(string[] args) => await new HostBuilder()
        .UseServiceProviderFactory(new AutofacServiceProviderFactory())
        .RunConsoleAsync();
}

It is causing a deadlock because their provider doesn’t implement IDisposable. Unfortunately, the ConsoleLifetime locks until it is disposed, and this only happens if:

1. The IServiceProvider implements IDisposable
2. The IServiceProvider disposes all IDisposable instances it creates

Autofac opted not to implement IDisposable in the past because if the service provider is supposed to be disposed, they should have put IDisposable on it (from https://github.com/autofac/Autofac.Extensions.DependencyInjection/issues/3#issuecomment-242068640). I’ve opened a new issue where I hope they’ll implement it (or allow me to), but I imagine this will be an issue for other DI containers.

[abe545]

As a workaround, I’ve been able to do the following:

using System;
using System.Threading.Tasks;
using Autofac.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

public class Program
{
    public static async Task Main(string[] args)
    {
        IDisposable container = null;
        await new HostBuilder()
            .UseServiceProviderFactory(new AutofacServiceProviderFactory())
            .ConfigureContainer<ContainerBuilder>((_, cb) => cb.RegisterBuildCallback(c => container = c))
            .RunConsoleAsync();
        container?.Dispose();
    }
}

[Tratcher]

I’m not sure the side-effects are worth it. We’ll get back to you.