DryIoc recursive dependency exception with Factory (Func<>)

Question

Hey I've switched over to DryIoc from Autofac. My code previously worked but now causes an exception "Recursive dependency is detected when resolving". (Code is simplified)

public class AFactory {
   public AFactory(Func<A> getA){ }
}

public class BFactory {
   public BFactory(Func<B> getB, AFactory factory){ }
}

public class A { 
   public A(IrrelevantService service, BFactory factory){ }
}

The actual code is complicated so assume that there is a reason that this code structure is necessary.

It's trying to resolve AFactory --> A --> BFactory --> AFactory and this is causing the issue. But since it's using a Func<> so it should be fine? (or at least it is in Autofac).

Is there a way to register this so that it doesn't throw this exception?

Answer 1

Here is the reason from the Func wrapper docs:

By default, does not permit recursive dependency.

The fix is described in the doc below or in the later section.

Here are all possible fixes:

using System;
using DryIoc;
                    
public class Program
{
    public static void Main()
    {
        var c = new Container(
            //rules => rules.WithFuncAndLazyWithoutRegistration() // fix1: make everything lazy resolvable preventing the recursive dependency check!
        );
        
        c.Register<A>(
            //setup: Setup.With(asResolutionCall: true) // fix2: makes A a dynamically resolvable
        );
        c.Register<AFactory>();
        
        c.Register<B>();
        c.Register<BFactory>(
            setup: Setup.With(asResolutionCall: true) // fix3: makes BFactory a dynamically resolvable - the fix is here and not in B because the BFactory is already loops to AFactory and making B dynamic is not enough
        );
        
        c.Register<IrrelevantService>();
        
        var af = c.Resolve<AFactory>();
        Console.WriteLine(af);
    }
    
    public class AFactory {
       public AFactory(Func<A> getA){ }
    }

    public class BFactory {
       public BFactory(Func<B> getB, AFactory aFactory){ }
    }

    public class A { 
       public A(IrrelevantService service, BFactory bFactory){ }
    }
    
    public class B {}
    public class IrrelevantService {}
}