removeEmpty.js

// From https://stackoverflow.com/questions/286141/remove-blank-attributes-from-an-object-in-javascript
const removeEmpty = (obj) => {
    return Object.keys(obj)
        .filter(k => obj[k] !== null && obj[k] !== undefined && obj[k] !== '')
        .reduce((newObj, k) => {
            return typeof obj[k] === 'object' ?
                Object.assign(newObj, {[k]: removeEmpty(obj[k])}) :  // Recurse.
                Object.assign(newObj, {[k]: obj[k]});  // Copy value.
        }, {});
}