qdate

WORK IN PROGRESS.

Small, light and quick handy date conversion functions.

Unlike timezone packages that drag along their own timezone database, qdate leverages the host system's native timezone support, making it much smaller.

This is a work in progress.

Summary

var qdate = require('qdate')
qdate.adjust(new Date(), -30, 'minute');

Api

abbrev( tzName ), getTimezoneAbbrev

return the three-character timezone abbreviation of the named timezone, or null if not known. Note that the abbreviation is what is currently in effect, and may change with daylight savings.

offset( tzName [,when] ), getTimezoneOffset

return the current offset as minutes west of GMT of the named timezone. This is what new Date().getTimezoneOffset() does for the default timezone. If when is specified, returns the offset in effect at that time. Throws an Error if the named timezone is not found.

list( ), getTimezoneList

return the list of known timezone names as an array of strings

adjust( timestamp, delta, unit [,tzName] )

return the Date corresponding to the timestamp adjusted by +/- delta units. Unit may be one of 'year', 'month', 'week', 'day', 'hour', 'minute', 'second' or 'millisecond'. Plurals and some common abbreviations are allowed.

strtotime( timespec [,tzName] )

convert the time specification to a Date. The time spec can be anything date --date can parse, like "+2 hours" or "3 weeks ago" or "9pm last Friday".

startOf( timestamp, unit [,tzName] )

return the Date corresponding to the start of the current unit. Unit may be any one of the time divisions listed under adjust(), eg 'year', 'month', 'week', etc.

following( timestamp, unit [,tzName] )

return the Date corresponding to the start of the named unit following the current. Unit as in adjust.

previous( timestamp, unit [,tzName] )

return the Date corresponding to the start of the named unit preceding the current. Unit as in adjust.

? format( timestamp, format [,tzName] )

TBD.

format the timestamp in the named timezone locale. Formatting by phpdate-js

? convert( timestamp, tzFromName, tzToName, [format] )

TBD.

convert the timestamp between timezones, and return a reformatted timestamp. The default format is "Y-m-d H:i:s". Formatting by phpdate-js

Todo

Change Log

• 0.2.0 - fix end-of-month clamping for year adjusts, round old date LMT fractional offets to 15 min
• 0.1.1 - tighten up the shell escaping of timespecs, speed up adjust
• 0.1.0 - use tzinfo to obtain timezone offsets
• 0.0.4 - refactor into a singleton, split into an array, startOf, previous, following methods
• 0.0.3 - depend on phpdate-js
• 0.0.2 - rename to qdate, test (tbd) with qnit
• 0.0.1 - adjust(), strtotime(), tz abbrev, tz offset, list all known tz names

Related

• ctime(3)
• tzname(3)
• strftime(3)
• phpdate-js - fast datetime formatting
• /bin/date +%Z @0
• /etc/timezone
• /usr/share/zoneinfo
• tzselect(1)