ghoussard

/**
 * MongoDB JSON Document Recursive Flat
 * @param {Object|Array} document MongoDB JSON Document
 * @param {string|undefined} prefixKey used by recursivity to prefix deeper keys with parent keys
 */
const flat = (document, prefixKey = undefined) => {
    const keys = Object.keys(document)

    keys.forEach(key => {
        const newKey = prefixKey ? `${prefixKey}_${key}` : key