ConfigureTestContainer not working with GenericHost

[alefranz]

Describe the bug

When using GenericHost, in tests ConfigureTestContainer is not executed.

To Reproduce

I've added a test in alefranz@282c153#diff-589b0cebe9e796b47e521f0318393df2R194-R208 to reproduce

Expected behavior

The delegate provided with ConfigureTestContainer should be executed

Additional context

This happen in 3.x

I'm looking at providing a fix for this but I would probably need some hint on the right place to address this.
Could you also confirm the behavior is not intentional?

@Tratcher I've seen you have worked to add support to ConfigureTestServices with GenericHost in https://github.com/aspnet/AspNetCore/pull/6585/files#diff-48af505b9d348e7e52da534c4590aef1R36 - Do you think it would need a similar logic to address this as well?

Thank you,
Alessio

[Tratcher]

There were reasons... I don't think ConfigureTestContainer was compatible. @javiercn might remember.

[javiercn]

@alefranz thanks for contacting us.

In previous versions the reason we had ConfigureTest(Services|Container) was due to the fact that the Configure(Services|Container) in Startup ran after all the ConfigureTest(Services|Container) methods applied to the host builder and we needed a way to run a Configure(Services|Container) callback after that happened to ensure services could be overriden for testing purposes.

When we moved to generic host, we changed that behavior and now the callbacks are queued in the order in which you register them, so when you do UseStartup the callback gets immediately queued. For that reason, if you are using generic host you shouldn't need the ConfigureTestContainer overload, you can simply call hostBuilder.ConfigureContainer after the call to UseStartup to tweak the container configuration.

I don't know what work @Tratcher did to make it work for ConfigureTestServices. I think the main reason we didn't do it is because we might have thought it was a much less common use case.

If ConfigureTestServices is supported on generic host, @Tratcher is ok with it, and it's not a big change, I'm supportive of a PR to make ConfigureTestContainer work too, if you want to give it a try.

I don't think we will fix ourselves as it's not a common scenario and there is an alternative way to achieve the same thing as described above, so this only helps you in migration scenarios.

Otherwise, I simply recommend closing the issue.

Hope this helps.

[alefranz]

I will investigate the scope of a change to make it work.
If this is too big of a change, what do you think about throwing an exception that clearly indicates that it is not supported in this scenario and what to use instead?
With the current behavior there is a risk to spend time in trying to understand why you don't have the expected services in the container (talking from experience 😅).

[roend83]

@javiercn I'm having a similar issue and have tried to make the updates that you suggested above. However, I'm having an issue because my Startup.ConfigureContainer method is always being called after my call to IHostBuilder.ConfigureContainer. It doesn't seem to matter what order I set them up with.

[roend83]

@javiercn I did confirm that if I remove Startup.ConfigureContainer and instead put that code into a call to IHostBuilder.ConfigureContainer then it does appear to all get executed in the right order.

[javiercn]

@roend83 It's impossible for us to diagnose what's going on in your case without a minimal repro project. How DI works with the new container is explained a bit better here:
https://github.com/aspnet/AspNetCore.Docs/issues/14973

[roend83]

AspNetCoreConfigurationIssue.zip
@javiercn Here's a minimal repro of what I'm seeing.

[javiercn]

@roend83 Thanks for the repro.

@Tratcher I took a quick look at the repro and @roend83 seems legit. Can you take a look?

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .UseServiceProviderFactory(new AutofacServiceProviderFactory())
                .ConfigureWebHostDefaults(webBuilder => { webBuilder.UseStartup<Startup>(); })
                .ConfigureContainer<ContainerBuilder>(builder =>
                {
                    if (!Startup.IsContainerConfigured)
                    {
                        throw new Exception("Startup.ConfigureContainer hasn't been called yet'");
                    }
                });

My understanding is that that should never throw as Startup.ConfigureContainer should run before the ConfigureContainer after it, isn't that the case?

[Tratcher]

This gets hit first:

>	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.CreateHostBuilder.AnonymousMethod__1_1(Autofac.ContainerBuilder builder) Line 27	C#
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.HostingHostBuilderExtensions.ConfigureContainer.AnonymousMethod__0(Microsoft.Extensions.Hosting.HostBuilderContext context, System.__Canon builder)	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.Internal.ConfigureContainerAdapter<Autofac.ContainerBuilder>.ConfigureContainer(Microsoft.Extensions.Hosting.HostBuilderContext hostContext, object containerBuilder)	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.HostBuilder.CreateServiceProvider()	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.HostBuilder.Build()	Unknown
 	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.Main(string[] args) Line 18	C#

And this second:

>	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Startup.ConfigureContainer(Autofac.ContainerBuilder builder) Line 56	C#
 	[Native to Managed Transition]	
 	[Managed to Native Transition]	
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.AspNetCore.Hosting.ConfigureContainerBuilder.InvokeCore(object instance, object container)	Unknown
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.AspNetCore.Hosting.ConfigureContainerBuilder.Invoke.__StartupConfigureContainer|0(object containerBuilder)	Unknown
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.AspNetCore.Hosting.ConfigureContainerBuilder.Invoke(object instance, object container)	Unknown
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.AspNetCore.Hosting.ConfigureContainerBuilder.Build.AnonymousMethod__0(object container)	Unknown
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.AspNetCore.Hosting.GenericWebHostBuilder.ConfigureContainer<System.__Canon>(Microsoft.Extensions.Hosting.HostBuilderContext context, System.__Canon container)	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.Internal.ConfigureContainerAdapter<Autofac.ContainerBuilder>.ConfigureContainer(Microsoft.Extensions.Hosting.HostBuilderContext hostContext, object containerBuilder)	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.HostBuilder.CreateServiceProvider()	Unknown
 	Microsoft.Extensions.Hosting.dll!Microsoft.Extensions.Hosting.HostBuilder.Build()	Unknown
 	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.Main(string[] args) Line 18	C#

ConfigureContainer actions are called in the order registered:
https://github.com/aspnet/Extensions/blob/b3a158ac055f1f8f76ed4a1a1c6ef860068cf63e/src/Hosting/Hosting/src/HostBuilder.cs#L228-L231
This is where generic web host finds and calls ConfigureContainer:
https://github.com/aspnet/AspNetCore/blob/c7972d45f83aab461d23616a9c17fe5fe3ad2226/src/Hosting/Hosting/src/GenericHost/GenericWebHostBuilder.cs#L260-L263
Which is called inline...

>	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.CreateHostBuilder.AnonymousMethod__1_0(Microsoft.AspNetCore.Hosting.IWebHostBuilder webBuilder) Line 24	C#
 	Microsoft.AspNetCore.dll!Microsoft.Extensions.Hosting.GenericHostBuilderExtensions.ConfigureWebHostDefaults.AnonymousMethod__0(Microsoft.AspNetCore.Hosting.IWebHostBuilder webHostBuilder)	Unknown
 	Microsoft.AspNetCore.Hosting.dll!Microsoft.Extensions.Hosting.GenericHostWebHostBuilderExtensions.ConfigureWebHost(Microsoft.Extensions.Hosting.IHostBuilder builder, System.Action<Microsoft.AspNetCore.Hosting.IWebHostBuilder> configure)	Unknown
 	Microsoft.AspNetCore.dll!Microsoft.Extensions.Hosting.GenericHostBuilderExtensions.ConfigureWebHostDefaults(Microsoft.Extensions.Hosting.IHostBuilder builder, System.Action<Microsoft.AspNetCore.Hosting.IWebHostBuilder> configure)	Unknown
 	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.CreateHostBuilder(string[] args) Line 22	C#
 	AspNetCoreConfigurationIssue.dll!AspNetCoreConfigurationIssue.Program.Main(string[] args) Line 18	C#

Ah, but UseStartup is delayed until ConfigureServices runs.
https://github.com/aspnet/AspNetCore/blob/c7972d45f83aab461d23616a9c17fe5fe3ad2226/src/Hosting/Hosting/src/GenericHost/GenericWebHostBuilder.cs#L203-L209
That explains the order inversion. Here's how it works out:

• Program: ConfigureWebHostDefaults, UseStartup
• Program: ConfigureContainer (register callback)
• Build, CreateServiceProvider
• ConfigureServices
  • UseStartup registers Startup.ConfigureContainer callback
• ConfigureContainer
  • Program ConfigureContainer callback
  • Startup ConfigureContainer callback

Trying to fix this would likely require moving the delayed call to UseStartup out of ConfigureServices. Not sure what other consequences that would have.

[GODBS]

I have the exact same issue. Is there a workaround that would allow us to bypass this issue?

[cdibbs]

@GODBS I ended up going the super-hacky route, for now. I hope this is fixed in 3.1.

internal static Action<ContainerBuilder> IntegTestOverrides = null;
public void ConfigureContainer(ContainerBuilder cb)
{
    cb.RegisterModule(new ApiRootModule());
    cb.RegisterType<StartupHttpPipeline>().As<IStartupHTTPPipeline>();
    IntegTestOverrides?.Invoke(cb);
}

[Tratcher]

@cdibbs no changes are planned for 3.1.

[cdibbs]

Will a fix come with a later patch to 3.1? Requiring hacks to override dependencies in your tests seems like a pretty undesirable thing to enter LTS with.