Add a way to get IReadOnlyDictionary<,> of keyed services

[MikeAlhayek]

.NET 8 introduced a way to register keyed services which is great addition. However, what if one wants to get a list of registered services along with their key. For example, during run time, I want to present the user a menu of some sort with all available services. The user will select the default service to use for the app. Without a way to expose the registered key, there is no real easy way to identify the keyed service and its key.

I think the missing piece here is the ability to be able to inject IReadOnlyDictionary<object?, object> which it'll be resolved by the IoC container. Alternatively, we can have a service with something like this

public interface IKeyedServiceProvider
{
    IReadOnlyDictionary<object?, T> GetServices<T>();
}

Along with extensions similar to the following

IReadOnlyDictionary<TKey, T> GetServices<TKey, T>()

Or add an extension on IServiceProvider that allows the above 2 methods.

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Issue Details

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.net 8 introduced a way to register keyed services which is great. However, what if one wants to get a list of services along with it's key. For example, during run time, I want to present the user a menu of available services. The user will select the default service to use. Without a way to expose the registration key, there is no real easy way to identify the keyed service.

I think the missing piece here is the ability to be able to inject IDictionary<object, object> which it'll be resolved by the IoC container.

Author:	MikeAlhayek
Assignees:	-
Labels:	untriaged, area-Extensions-DependencyInjection
Milestone:	-

[davidfowl]

I don’t think we’d do it that way but I agree with the sentiment that this feature is missing.

[MikeAlhayek]

@davidfowl thanks for your comment. Other using a dictionary, how would you do it?

I updates my Issue by providing alternative solution using a provider.

[jtkech]

@MikeAlhayek

Your dictionary may need to take into account that for the same service key and service type multiple services may have been registered, with different implementation types, instances or factories but with the same service type.

[steveharter]

The proposal here adds to the existing interface IKeyedServiceProvider which we can't really do. Although it is possible now to add to an existing interface by leveraging DIMs or Default Interface Methods, but since DI supports .NET Framework I don't think that is available. So we'd need another interface so a provider can opt-in.

[steveharter]

@benjaminpetit thoughts?