I am having a difficulty at the moment, which would be as follows. I needed to find a solution to be able to assign a certain service, that would be “Gift Wrap”, to be assigned to all the products, I could verify that until then it is only possible to assign a service to a sku, manually, would there be some way to already assign everything at once, for all the products of the shop or even future products ?
There isn’t a native way to do that. Attachments and services are generic ways to add data to the items in a cart, and they are necessarily made individually for each item in the cart.
So, thinking of a way to achieve it, you need a custom implementation in the front-end to watch the desired state (with/without gift wrap) and apply it to every item through the API according they are available in the cart and ensure that all of them are in the same state as the customer goes through the purchase steps.