The operator $currentDate is used to set the value of a given field as the current date or timestamp. If the field is not present already, it will be created with the current date or timestamp value.

Providing a field name with a value of true will insert the current date as a Date.

const query = async () => {
  const result = await Product.findOneAndUpdate(
    { name: "Airpods Pro" },
    { $currentDate: { created_date: true } },
    { returnNewDocument: true }
  )
  console.log(result)
}

query()

The preceding findOneAndUpdate() operation sets the created_date field using the $currentDate operator. The field created_date has a value of true, which defaults to a Date type.

We can see in the output below that the field created_date has a value of the Date type.

{
   _id: new ObjectId("61a366483394265a2770d75c"),
   name: 'Airpods Pro',
   brand: 'Apple',
   category: 'Earphones',
   price: 99.99,
   soldQty: 240,
   __v: 0,
   created_date: 2021-11-28T16:28:08.494Z
 }