This article is decent. http://khkonsulting.com/2016/06/getting-serial-number-form-using-soap/ http://khkonsulting.com/2016/06/getting-serial-number-form-u...

This article is decent. http://khkonsulting.com/2016/06/getting-serial-number-form-using-soap/ http://khkonsulting.com/2016/06/getting-serial-number-form-u... Basically, the backend is a SOAP server and the PDF is the client. So, xml and wsdl, no json.