Improve debugging experience of Microsoft.Extensions.DependencyInjection

[JamesNK]

Microsoft.Extensions.DependencyInjection debug experience could be improved.

I think there are two primary APIs to focus on: ServiceCollection and IServiceProvider implementations.

ServiceCollection is already pretty good. It could be improved with a debugger display that shows the count and whether it's read-only.

IServiceProvider is difficult to debug. Useful information to make available:

• Its service descriptors (the information that ServiceCollection displays)
• Is it a scoped or root service provider
• Is it disposed
• Realized services
• Registered disposable services
• More that I haven't thought of?

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Issue Details

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Microsoft.Extensions.DependencyInjection debug experience could be improved.

I think there are two primary APIs to focus on: ServiceCollection and IServiceProvider implementations.

ServiceCollection is already pretty good. It could be improved with a debugger display that shows the count and whether it's read-only.

IServiceProvider is difficult to debug. Useful information to make available:

• Its service descriptors (the information that ServiceCollection displays)
• Is it a scoped or root service provider
• Is it disposed
• Realized services
• Registered disposable services
• More that I haven't thought of?

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

[ericstj]

@steveharter this seems like a nice thing to improve in 8.0.

[kwaazaar]

I would like something that helps with detecting an attempt to resolve a circular dependency that was not detected on build (eg when using a factory, like services.AddTransient<IService>(sp => sp.GetRequiredService<MyService>())).

I know my codebase needs refactoring, but it's so big (and not created by myself), that I have no idea where those circular dependencies are. Result is now that I have to start the application and see if memory usage will suddenly increase dramatically (result of the circular dependency) and then manually check all code to find where the cause could be.

Logging could help, but detecting on build OR resolve would help even more.
And since I know from my factory-code which types I create, I could even provide it to the TryAdd/Add on the servicecollection, so it could use that information for detection. Something like this: services.AddTransient<IService>(sp => sp.GetRequiredService<MyService>(), new[] { typeof(MyService) }).

[JamesNK]

Fixed by #88082