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Create a formatted, locale-aware string representation of a datetime.

This module contains general purpose functions for localizing and displaying date-times by timezone, locale and preferred language.”

Most of the heavy lifting is done by the |’moments’ js library with the moment-with-locales and moment-timezones add-ons.


var context = {
   datetime: '2016-10-14 08:00:00+00:00',
   timezone: 'Pacific/Kiritimati',
   language: 'ar',
   format: DateUtils.dateFormats.shortDate
localized_date = DateUtils.localize(context);


Renders a localized date/time in a standard format.


context: string, - datetime: The (UTC) datetime server-side string. - timezone: {string} (optional) the user set time zone preference, or ‘None’ if unset. This should be in a format like ‘Region/Locale’, e.g. ‘Atlantic/Azores’. Defaults to ‘UTC’. - language: {string} (optional), the user set language, an ISO 639-1 language string, defaults to ‘en’ - format: {object} (optional), a format constant. Defaults to DEFAULT_FORMAT.

Returns: string, A formatted, timezone-offset, internationalized date and time.


Converts a string to mutable ‘moment’ datetime object.

The input datetimeString can be just a date, a date and time, or a complex date/time string with TZ offset. This is fairly wide-open, as many strings will satisfy this requirement. (e.g. 01-01-16 and Jan 1, 2016, and 2016-01-01 01:00:00+00:00 will work)

The recommendation is to use a fully informed string, e.g. ‘2016-01-01 01:00:00+00:00’, to limit possible date, time, and timezone ambiguities.


  • datetimeString.: string, A string representation of a datetime.

Returns: object, A moment.js UTC datetime object.

DateUtils.localizeTime(dateTimeObject, timezone)

Returns a new time that is offset by the requested timezone.


dateTimeObject: Object, A moment.js datetime object.

timezone: string, A timezone representation, e.g. ‘America/New_York’.

Returns: object, A moment.js datetime object in a determined timezone.


Helper function to determine system timezone, and fallback to UTC Determines timezone from argument, falling back to system/browser settings, then UTC.

Returns: string, Will attempt to return a determined timezone string, with a fallback to UTC.

DateUtils.getDisplayTime(localTime, language, format)

Generate a timezone-aware and language-aware string.

This includes a param for standard formatting constants.

Browser preferred language is currently overridden by platform-set language preference. If no preference is set, the function attempts to determine the locale settings (e.g. en-US) from the browser preferences.

This function will default to UTC/en-US display in default format in the case of an unresolvable language or timezone

preferred_language = ‘en’ yields Oct. 14, 2016 09:00 BST

preferred_language = ‘ru’ yields 14 окт 2016 г. 09:00 BST


localTime: object, A moment.js datetime object offset to a determined timezone.

language: string, an ISO 639-1 language code (e.g. ‘en-US’, ‘fr’)

format: object, (optional) A desired date format, via the dateFormatEnum.

Returns: string, A language/timezone aware localized string


Helper function to determine sys/browser language (if unpassed)


language: string, (optional) an ISO 639-1 language code (e.g. ‘en-US’, ‘fr’)

Returns: string, an ISO 639-1 language code (e.g. ‘en-US’, ‘fr’)


Helper function to determine format constant.

Defaults to DEFAULT_FORMAT if malformed or unpassed.


format: object, (optional) A format constant.

Returns: string, A format constant.


Helper function to determine variable/context validity.


candidateVariable: string, to test

Returns: boolean