The main problem here is, in my point of view, the lack of documentation on over how to write the HTTP queries. In particular de body in POST and PUT operations, as the GET that can be done using blank body, is pretty easy.
When I do any kind of tries on how to post or how to update it always shows on screen in which is obvious that data (body) is missing (due to incorrect formating) or that ARTICLE, a part of the body is, again, not correctly formed.
Thanks
Im trying through postman all the combinations that I tried.
There are some PHP client examples on GitHub available. I'm using the REST API daily with PowerShell. What exactly do you looking for, because the payload is described in the Perldocs of the API.