ASP.Net Core 3.1 - DbContext (Transient Disposable) store in Scope Container

[Ager1912]

Hi,
I am using DryIoc (last release version) for Dependency Injection.
In my application (Asp.net Core 3.1), I am using Entity Framework.
My AppDbContext hinerits DbContext and implements IDisposable
I also use UnitOfWork pattern and the class is disposable.

These two objects are declared as Transient.
I follow the documentation that explains the context with Transient Disposable objects:
https://github.com/dadhi/DryIoc/blob/master/docs/DryIoc.Docs/ReuseAndScopes.md

For my AppDbContext, I resolve this service manually. Same thing for my UnitOfWork. At the end I call Dispose method.
But these two instances are not destroyed and are stored in the Singleton Scope of the DryIoc Container.

I did some tests and use JetBrain dotMemory.
My test is to call around 300 times a method

• Call controler
• open UnitOfWork
• create AppDbContext
• call database to get my data
• close / dispose objects.
  At the end, I have around 300 times my AppDbContext and my UnitOfWork in the scope of the container:

I try a lot of combinaison of creation of container but each time, it is the same thing:

var container = new Container(rules => rules.With(propertiesAndFields: request => request.ServiceType.Name.EndsWith("Controller") ? PropertiesAndFields.Auto(request) : null) // .WithoutThrowOnRegisteringDisposableTransient() // .WithTrackingDisposableTransients() .WithoutThrowIfDependencyHasShorterReuseLifespan()) .WithDependencyInjectionAdapter(services); Result: memory is growing up fast because of these two kind of objects stored in the scope.

If I comment .WithoutThrowOnRegisteringDisposableTransient(), my code is still working (I thought an exception would be thrown)

I tried also to declare these services as Scoped (for each http request) but it does not work because I don't create scope for each query. (Exception thrown and a scope is automatically opened per each web request by Asp .Net Core framework).

Maybe I need to dispose scope at the end of each request?

Thanks for your help.

[dadhi]

Maybe I need to dispose scope at the end of each request?

Likely yes. and the creation of the scope for each query / request seems like a natural choice for Unit-of-work pattern. Otherwise, transient disposables are accumulating at the top level (Singleton) because we need to track them somewhere for disposal, and we have no Scope to put them in.

[Ager1912]

Hello,
Thanks for your quick answer.
I change the resolution by calling New method instead of Resolve.
I hadn't paid attention to this method. It is sloved my issue.

Last question: is there a way/a method to release an instance in the scope?

[dadhi]

The method is Disposing the scope.

[Ager1912]

Hello,
Ok
Sorry for my questions but I don't understand something.
Actually, I used the New method instead of Resolve but I still have some instances of my UnitOfWork and my DbContext. Do you have any idea why?

On StackOverFlow, I asked how to have one scope per http request.
You told me a scope is automatically open per each web request by Asp .Net Core framework, you don't need to bother.

So I don't open any Scope.
In my container, ScopeContext, CurrentScope are null. Only SingletonScope is not null.
So I can't dispose this scope.
Is there another way?

Now if I want to open a scope per HTTP Request, I don't know where I can do it.
I follow the sample:
https://bitbucket.org/dadhi/dryioc/src/8e609b011beafd71236f9cfe3bb2d3e0589e76ae/NetCore/src/DryIoc.AspNetCore.Sample/
But because I don't have any scope opened, I can't call the method Resolve or New on a service declared as Scoped. So in my application, all services are transient or singleton.
Maybe it is a wrong way?

I am a little bit wonfused. But the memory of my application is growing up and between two snapshots, the Scope size is growing up.

Thanks for your help.

[dadhi]

@Ager1912

I have released the new DryIoc.Microsoft.DependencyInjection v4
and created the fresh sample for ASP .NET Core https://github.com/dadhi/DryIoc/tree/master/samples/DryIoc.AspNetCore31.WebApi.Sample

Please check it out.

[Ager1912]

Hi,
Thanks.
I upgraded the version.
And for my issue of memory, I open a Scope and Dispose it when my unit of work is disposed.

Thanks for your time.
Adrien