How to upload/download input and result files from my javascript program to/from my cloud workspace ?

I'm newbie (less than week).

I published my workspace to my cloud. My workspace does necessary translation between file formats and coordinate systems.

Now I need to upload to this cloud workspace my input file and download from there the result file.

This should be done by my javascript program.

1. How do I set my workspace to be able to get input and send the output from/to my javascript program?
2. How do I, by my javascript program, upload the input file and download the result file, all by my javascript program?

I have not yet found neither relevant documentation, nor relevant code examples for my needs as I explained them above.

For example, It'll help me If I knew how to do it for the "Easy Translator" example in

https://playground.fmeserver.com/demos/

Help will be greatly appreciated.

P.S. - important

Now I think maybe Upload File In Session is more suitable to adapt for my needs. If it's right, then I'll appreciate help in adapting it.

Michael