Injected or scoped ServiceProvider does not support Keyed services

[CarnaViire]

Originally posted by @CarnaViire in #89446 (comment)

Scoped ServiceProvider, acquired from a DI scope created by IServiceScopeFactory, [UPD: or any injected IServiceProvider instance] does not implement the IKeyedServiceProvider:

runtime/src/libraries/Microsoft.Extensions.DependencyInjection/src/ServiceLookup/ServiceProviderEngineScope.cs

Line 15 in 3dd73e6

internal sealed class ServiceProviderEngineScope : IServiceScope, IServiceProvider, IAsyncDisposable, IServiceScopeFactory

Because of that, it is impossible to use Keyed services within HttpClientFactory now, see #89446

cc @benjaminpetit @halter73 @steveharter

Tagging subscribers to this area: @dotnet/area-extensions-dependencyinjection
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Scoped ServiceProvider, acquired from a DI scope created by IServiceScopeFactory, does not implement the IKeyedServiceProvider (see ServiceProviderEngineScope.cs)

Originally posted by @CarnaViire in #89446 (comment)

Because of that, it is impossible to use Keyed services within HttpClientFactory now, see #89446

Author:	CarnaViire
Assignees:	-
Labels:	area-Extensions-DependencyInjection
Milestone:	-

[CarnaViire]

LMK if you need a runnable repro, but it should be along the lines of

1. Register a keyed singleton
2. Build ServiceProvider, resolve IServiceScopeFactory and create a scope
3. Try to resolve the keyed singleton from scope's service provider.

You'll get an exception System.InvalidOperationException: This service provider doesn't support keyed services.

[CarnaViire]

So it's not just a scoped service provider, but also any injected service provider, so I cannot even work around this in tests by suppressing scopes.

Though, to my understanding, the root cause is the same (ServiceProviderEngineScope not implementing the interface).

The repro is:

var services = new ServiceCollection();
services.AddKeyedSingleton<Service>("test", new Service(123));
services.AddSingleton<ServiceWithProvider>();

var sp = services.BuildServiceProvider();
var serviceWithProvider = sp.GetRequiredService<ServiceWithProvider>();

serviceWithProvider.Provider.GetRequiredKeyedService<Service>("test"); // throws InvalidOperationException

public record class Service(int Value);
public record class ServiceWithProvider(IServiceProvider Provider);