Flatten javascript objects into a single-depth object

const flatten = (object, prefix = '') =>
  Object.keys(object).reduce(
    (prev, element) =>
      object[element] &&
      typeof object[element] === 'object' &&
      !Array.isArray(object[element])
        ? { ...prev, ...flatten(object[element], `${prefix}${element}.`) }
        : { ...prev, ...{ [`${prefix}${element}`]: object[element] } },
    {},
  );