How do I send a form with a request promise?

I am trying to use the request-promise library or anything similar to send files via a post request from node to another machine that is running Node. Using the normal request module I could so something like

var req = request.post(url, function (err, resp, body) { if (err) {    console.log('Error!');  } else {    console.log('URL: ' + body);  }});var form = req.form();form.append('file', '<FILE_DATA>', {  filename: 'myfile.txt',  contentType: 'text/plain'});

This code is from the question:
Uploading file using POST request in Node.js however it is not using promises.

Can anyone explain how to do the same thing but with the request-promise library or if there is any other way to promisify this?