-s puts the different objects at root in an array.
DataKnead seems to be a very handy tools for data conversion between csv, json, excel and xml files.
xml2json seems enough for xml to json translation:
xml2json -t xml2json -o file.json file.xml --strip_text
To install it, you need to execute:
git clone https://github.com/hay/xml2json.git
python setup.py build
chmod +x cp build/*/xml2json.py
cp build/*/xml2json.py ~/.local/bin/xml2json