HTTP Task: Submitting File

#1

Is there a guide on steps for Submitting a file via the HTTP Task?
When I used the extression ${file_field} only the name was sent to the HTTP Target.

I used the following work-around to bypass the problem

HTTP Task > Request Body

file_name=${file}&extension=${format}&operation=${operation}&name=${name}

And from the Target Service (using basic auth header)

http://ip:port/flowable-task/content-api/content-service/content-items/{file_name}/data

Any better ways?