command.php

<?php

// example 1
class ProductController implements CreateProductResponder
{
    private $response;

    public function createProductAction(Request $request)
    {
        $this->response = new Response();

        $this->get('command_bus')->handle(
            new CreateProductCommand('Foo', $this)
        );

        return $this->response;
    }

    public function productCreated(ProductId $productId)
    {
        $this->response = new RedirectResponse(sprintf('/some/url/%s', (string) $productId));
    }
}

CreateProductResponder.php

<?php

interface CreateProductResponder
{
     public function productCreated(ProductId $productId);
}

ProductId is UUID