So our WMS-deliverer has now made a REST API. After testing it I must say that it's a bit easier to handle. Compared to working with SOAP. At least from the client-side. The developer site for this is here: https://developer.ongoingwarehouse.com/REST/v1/index.html#/

In the Communicating with the REST API-article I got order-info using cURL, HTTP GET - method. Now I'm going to create an order using cURL, JSON-datafile and HTTP PUT - method.