// Define the command result
public record CreateProductCommandResult(Guid Id);

// Define a command with a result
public record CreateProductCommand(string Title) : ICommand<CreateProductCommandResult>;

// Implement a command validator
public class CreateProductCommandValidator : ICommandValidator<CreateProductCommand>
{
    public Task ValidateAsync(CreateProductCommand command, CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(command.Title))
            throw new ValidationException("Product title cannot be empty");
            
        return Task.CompletedTask;
    }
}

// Implement a command handler
public class CreateProductCommandHandler : ICommandHandler<CreateProductCommand, CreateProductCommandResult>
{
    private readonly IProductRepository _repository;
    
    public CreateProductCommandHandler(IProductRepository repository)
    {
        _repository = repository;
    }
    
    public async Task<CreateProductCommandResult> HandleAsync(CreateProductCommand command, CancellationToken cancellationToken = default)
    {
        var product = new Product(Guid.NewGuid(), command.Title);
        
        await _repository.SaveAsync(product, cancellationToken);
        
        return new CreateProductCommandResult(product.Id);
    }
}

// Configure in ASP.NET Core
services.AddLiteBus(liteBus =>
{
    liteBus.AddCommandModule(module =>
    {
        module.RegisterFromAssembly(typeof(CreateProductCommand).Assembly);
    });
});

// Use in a controller or service
public class ProductsController : ControllerBase
{
    private readonly ICommandMediator _commandMediator;
    
    public ProductsController(ICommandMediator commandMediator)
    {
        _commandMediator = commandMediator;
    }
    
    [HttpPost]
    public async Task<ActionResult<CreateProductCommandResult>> CreateProduct(CreateProductCommand command)
    {
        var result = await _commandMediator.SendAsync(command);
        return Ok(result);
    }
}