Decor with transient servive and delegate. Could not find a parameterless constructor

[robertgm]

Cannot get service inside Transient registration of service.
Project on Git with sample: DecorTransientDelegateBug

Class with Decor attribute:

public class ServiceBLL : IServiceBLL
{
    private readonly IServiceDependencyBLL serviceDependencyBLL;

    public ServiceBLL(IServiceDependencyBLL serviceDependencyBLL)
    {
        this.serviceDependencyBLL = serviceDependencyBLL;
    }

    [Decorate(typeof(CacheDecorator))]
    public string GetValueB()
    {
        return "dependency" + this.serviceDependencyBLL.GetValueA();
    }
}

Service registration:

builder.Services.AddControllers();

builder.Services.AddDecor();
builder.Services.AddSingleton<CacheDecorator>();
builder.Services.AddSingleton<IServiceDependencyBLL, ServiceDependencyBLL >().Decorated();
builder.Services.AddSingleton<ServiceBLL>().Decorated();

builder.Services.AddTransient<Func<string, IServiceBLL>>(serviceProvider => account => {
    switch (account)
    {
        case "countryA":
            return serviceProvider.GetService<ServiceBLL>(); // error
        default:
            throw new Exception("Country does not exist.");
    }
});

When application calls serviceProvider.GetService<ServiceBLL>(); it get error:

 Castle.DynamicProxy.InvalidProxyConstructorArgumentsException: 'Can not instantiate proxy of class: DecorTransientDelegateBug.BLL.ServiceBLL.
Could not find a parameterless constructor.'

I need to have constructor with parameter because I need to use other service that have to be injected in ServiceBLL class.

[lawrence-laz]

Decorating concrete types requires them to have a parameterless constructor. This is a limitation of the Castle Core library (discussed here castleproject/Core#532).

As a pretty simple workaround you can register ServiceBLL as an interface, which will not require a parameterless constructor:

Closing as a duplicate of #4