How to POST a file with attributes as form-data to a REST service?

Hi all,

I am trying to POST a doc file to a REST service. I make use of the JAVA action of the RestServices with useformdata:true.

As result I receive an error 500; internal server error/unknown error.

Response status: 500 Internal Server Error, ETag: null, body: '{"succeeded":false,"shortMsg":"Unexpected error:null"}']

Seen this is normally a pretty simple call (see attachment),

I think I miss something in my microflow. Could you guys tell me how I can build the same in a microflow?

Edit 1: I reproduced the same error with Postman (Chrome extension to execute webservices); when there is no templateFile i got the same error. So I think that in Mendix the file and the attributes are not well formed by their names into one object...

I do now as follow:

1 - filedocument object with 2 attributes (no binary attribute included)

2 - then I do a post with submist as formdata : true...