Working With Dates

    When you create a user document, Mongoose will cast the value to a using the Date() constructor.

    1. const user = new User({
    2.   name: 'Jean-Luc Picard',
    3.   lastActiveAt: '2002-12-09'
    4. });
    5. user.lastActiveAt instanceof Date; // true

    An invalid date will lead to a CastError when you .

    1. const episodeSchema = new mongoose.Schema({
    2.   title: String,
    3.   airedAt: {
    5.     // Star Trek: The Next Generation
    6.     min: '1987-09-28',
    7.     max: '1994-05-23'
    8.   }
    9. });
    10. const Episode = mongoose.model('Episode', episodeSchema);
    12. const ok = new Episode({
    13.   title: 'Encounter at Farpoint',
    14.   airedAt: '1987-09-28'
    15. });
    16. ok.validateSync(); // No error
    19.   airedAt: '1999-06-02'
    20. });
    21. bad.airedAt; // "1999-06-02T00:00:00.000Z"
    23. // Path `airedAt` (Tue Jun 01 1999 20:00:00 GMT-0400 (EDT)) is after
    24. // maximum allowed value (Sun May 22 1994 20:00:00 GMT-0400 (EDT)).
    25. bad.validateSync();

    MongoDB supports querying by date ranges and sorting by dates. Here’s some examples of querying by dates, date ranges, and sorting by date:

    Date casting has a couple small cases where it differs from JavaScript’s native date parsing. First, Mongoose looks for a valueOf() function on the given object, and calls valueOf() before casting the date. This means Mongoose can cast to dates automatically.

    1. const moment = require('moment');
    2. const user = new User({
    3.   name: 'Jean-Luc Picard',
    4.   lastActiveAt: moment.utc('2002-12-09')
    5. });

    Mongoose converts numeric strings that contain numbers outside the range of representable dates in JavaScript and converts them to numbers before passing them to the date constructor.

    , which means that Mongoose does not store timezone information by default. When you call Date#toString(), the JavaScript runtime will use your OS’ timezone.