момент, получите начало недели в DateTime

const today = moment();
const from_date = today.startOf('week');
const to_date = today.endOf('week');
console.log({
  from_date: from_date.toString(),
  today: moment().toString(),
  to_date: to_date.toString(),
});

// {
//   from_date: "Sun Apr 22 2018 00:00:00 GMT-0500",
//   today: "Thu Apr 26 2018 15:18:43 GMT-0500",
//   to_date: "Sat Apr 28 2018 23:59:59 GMT-0500"
// }
Foolish Flatworm