Code Quiz

Captive Dependency in Service Lifetimes

Spot the captive dependency bug when mixing singleton and scoped service lifetimes.

Codecsharp

// Program.cs (ASP.NET Core)
builder.Services.AddScoped<IOrderRepository, OrderRepository>();
builder.Services.AddSingleton<IOrderService, OrderService>();

public class OrderService : IOrderService
{
    private readonly IOrderRepository _repo;

    // OrderService is a singleton
    public OrderService(IOrderRepository repo)
    {
        _repo = repo;
    }

    public void Place(Order order) => _repo.Save(order);
}

What is the bug in this dependency registration/injection?

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