Firebase recursive getDocWithSubcollections

export const getDocWithSubcollections = async (doc: any) => {
  const item: any = { id: doc.id, ...doc.data() };
  const subcollections = await doc.ref.listCollections();
  for (const sub of subcollections) {
    const arr = [];
    const subDocs = (await sub.get()).docs;
    for (const d of subDocs) {
      arr.push(await getDocWithSubcollections(d));
    }
    item[sub.id] = arr;
  }
  return item;
};