Class | TimeZone
In: | lib/active_support/values/time_zone.rb
Parent: | Object

The TimeZone class serves as a wrapper around TZInfo::Timezone instances. It allows us to do the following:

- Limit the set of zones provided by TZInfo to a meaningful subset of 142 zones.
- Retrieve and display zones with a friendlier name (e.g., "Eastern Time (US & Canada)" instead of "America/New_York").
- Lazily load TZInfo::Timezone instances only when they‘re needed.
- Create ActiveSupport::TimeWithZone instances via TimeZone‘s `local`, `parse`, `at` and `now` methods.

If you set `config.time_zone` in the Rails Initializer, you can access this TimeZone object via `Time.zone`:

      # environment.rb:
      Rails::Initializer.run do |config|
        config.time_zone = "Eastern Time (US & Canada)"
      end

      Time.zone       # => #<TimeZone:0x514834...>
      Time.zone.name  # => "Eastern Time (US & Canada)"
      Time.zone.now   # => Sun, 18 May 2008 14:30:44 EDT -04:00

The version of TZInfo bundled with Active Support only includes the definitions necessary to support the zones defined by the TimeZone class. If you need to use zones that aren‘t defined by TimeZone, you‘ll need to install the TZInfo gem (if a recent version of the gem is installed locally, this will be used instead of the bundled version.)

### Methods

<=> [] all at formatted_offset local local_to_utc new new now parse period_for_local period_for_utc to_s today tzinfo us_zones utc_offset utc_to_local

### Included Modules

Comparable

### Constants

MAPPING | = | { "International Date Line West" => "Pacific/Midway", "Midway Island" => "Pacific/Midway", "Samoa" => "Pacific/Pago_Pago", "Hawaii" => "Pacific/Honolulu", "Alaska" => "America/Juneau", "Pacific Time (US & Canada)" => "America/Los_Angeles", "Tijuana" => "America/Tijuana", "Mountain Time (US & Canada)" => "America/Denver", "Arizona" => "America/Phoenix", "Chihuahua" => "America/Chihuahua", "Mazatlan" => "America/Mazatlan", "Central Time (US & Canada)" => "America/Chicago", "Saskatchewan" => "America/Regina", "Guadalajara" => "America/Mexico_City", "Mexico City" => "America/Mexico_City", "Monterrey" => "America/Monterrey", "Central America" => "America/Guatemala", "Eastern Time (US & Canada)" => "America/New_York", "Indiana (East)" => "America/Indiana/Indianapolis", "Bogota" => "America/Bogota", "Lima" => "America/Lima", "Quito" => "America/Lima", "Atlantic Time (Canada)" => "America/Halifax", "Caracas" => "America/Caracas", "La Paz" => "America/La_Paz", "Santiago" => "America/Santiago", "Newfoundland" => "America/St_Johns", "Brasilia" => "America/Argentina/Buenos_Aires", "Buenos Aires" => "America/Argentina/Buenos_Aires", "Georgetown" => "America/Argentina/San_Juan", "Greenland" => "America/Godthab", "Mid-Atlantic" => "Atlantic/South_Georgia", "Azores" => "Atlantic/Azores", "Cape Verde Is." => "Atlantic/Cape_Verde", "Dublin" => "Europe/Dublin", "Edinburgh" => "Europe/Dublin", "Lisbon" => "Europe/Lisbon", "London" => "Europe/London", "Casablanca" => "Africa/Casablanca", "Monrovia" => "Africa/Monrovia", "UTC" => "Etc/UTC", "Belgrade" => "Europe/Belgrade", "Bratislava" => "Europe/Bratislava", "Budapest" => "Europe/Budapest", "Ljubljana" => "Europe/Ljubljana", "Prague" => "Europe/Prague", "Sarajevo" => "Europe/Sarajevo", "Skopje" => "Europe/Skopje", "Warsaw" => "Europe/Warsaw", "Zagreb" => "Europe/Zagreb", "Brussels" => "Europe/Brussels", "Copenhagen" => "Europe/Copenhagen", "Madrid" => "Europe/Madrid", "Paris" => "Europe/Paris", "Amsterdam" => "Europe/Amsterdam", "Berlin" => "Europe/Berlin", "Bern" => "Europe/Berlin", "Rome" => "Europe/Rome", "Stockholm" => "Europe/Stockholm", "Vienna" => "Europe/Vienna", "West Central Africa" => "Africa/Algiers", "Bucharest" => "Europe/Bucharest", "Cairo" => "Africa/Cairo", "Helsinki" => "Europe/Helsinki", "Kyev" => "Europe/Kiev", "Riga" => "Europe/Riga", "Sofia" => "Europe/Sofia", "Tallinn" => "Europe/Tallinn", "Vilnius" => "Europe/Vilnius", "Athens" => "Europe/Athens", "Istanbul" => "Europe/Istanbul", "Minsk" => "Europe/Minsk", "Jerusalem" => "Asia/Jerusalem", "Harare" => "Africa/Harare", "Pretoria" => "Africa/Johannesburg", "Moscow" => "Europe/Moscow", "St. Petersburg" => "Europe/Moscow", "Volgograd" => "Europe/Moscow", "Kuwait" => "Asia/Kuwait", "Riyadh" => "Asia/Riyadh", "Nairobi" => "Africa/Nairobi", "Baghdad" => "Asia/Baghdad", "Tehran" => "Asia/Tehran", "Abu Dhabi" => "Asia/Muscat", "Muscat" => "Asia/Muscat", "Baku" => "Asia/Baku", "Tbilisi" => "Asia/Tbilisi", "Yerevan" => "Asia/Yerevan", "Kabul" => "Asia/Kabul", "Ekaterinburg" => "Asia/Yekaterinburg", "Islamabad" => "Asia/Karachi", "Karachi" => "Asia/Karachi", "Tashkent" => "Asia/Tashkent", "Chennai" => "Asia/Kolkata", "Kolkata" => "Asia/Kolkata", "Mumbai" => "Asia/Kolkata", "New Delhi" => "Asia/Kolkata", "Kathmandu" => "Asia/Katmandu", "Astana" => "Asia/Dhaka", "Dhaka" => "Asia/Dhaka", "Sri Jayawardenepura" => "Asia/Dhaka", "Almaty" => "Asia/Almaty", "Novosibirsk" => "Asia/Novosibirsk", "Rangoon" => "Asia/Rangoon", "Bangkok" => "Asia/Bangkok", "Hanoi" => "Asia/Bangkok", "Jakarta" => "Asia/Jakarta", "Krasnoyarsk" => "Asia/Krasnoyarsk", "Beijing" => "Asia/Shanghai", "Chongqing" => "Asia/Chongqing", "Hong Kong" => "Asia/Hong_Kong", "Urumqi" => "Asia/Urumqi", "Kuala Lumpur" => "Asia/Kuala_Lumpur", "Singapore" => "Asia/Singapore", "Taipei" => "Asia/Taipei", "Perth" => "Australia/Perth", "Irkutsk" => "Asia/Irkutsk", "Ulaan Bataar" => "Asia/Ulaanbaatar", "Seoul" => "Asia/Seoul", "Osaka" => "Asia/Tokyo", "Sapporo" => "Asia/Tokyo", "Tokyo" => "Asia/Tokyo", "Yakutsk" => "Asia/Yakutsk", "Darwin" => "Australia/Darwin", "Adelaide" => "Australia/Adelaide", "Canberra" => "Australia/Melbourne", "Melbourne" => "Australia/Melbourne", "Sydney" => "Australia/Sydney", "Brisbane" => "Australia/Brisbane", "Hobart" => "Australia/Hobart", "Vladivostok" => "Asia/Vladivostok", "Guam" => "Pacific/Guam", "Port Moresby" => "Pacific/Port_Moresby", "Magadan" => "Asia/Magadan", "Solomon Is." => "Asia/Magadan", "New Caledonia" => "Pacific/Noumea", "Fiji" => "Pacific/Fiji", "Kamchatka" => "Asia/Kamchatka", "Marshall Is." => "Pacific/Majuro", "Auckland" => "Pacific/Auckland", "Wellington" => "Pacific/Auckland", "Nuku'alofa" => "Pacific/Tongatapu" |  | Keys are Rails TimeZone names, values are TZInfo identifiers
ZONES | = | []
ZONES_MAP | = | {}
US_ZONES | = | ZONES.find_all { |z| z.name =~ /US|Arizona|Indiana|Hawaii|Alaska/ }

### External Aliases

new | -> | create

### Attributes

name | [R] |

### Public Class methods

[](arg)

Locate a specific time zone object. If the argument is a string, it is interpreted to mean the name of the timezone to locate. If it is a numeric value it is either the hour offset, or the second offset, of the timezone to find. (The first one with that offset will be returned.) Returns `nil` if no such time zone is known to the system.

all()

Return an array of all TimeZone objects. There are multiple TimeZone objects per time zone, in many cases, to make it easier for users to find their own time zone.

new(name, utc_offset, tzinfo = nil)

Create a new TimeZone object with the given name and offset. The offset is the number of seconds that this time zone is offset from UTC (GMT). Seconds were chosen as the offset unit because that is the unit that Ruby uses to represent time zone offsets (see Time#utc_offset).

new(name)

Return a TimeZone instance with the given name, or `nil` if no such TimeZone instance exists. (This exists to support the use of this class with the `composed_of` macro.)

us_zones()

A convenience method for returning a collection of TimeZone objects for time zones in the USA.

### Public Instance methods

<=>(zone)

Compare this time zone to the parameter. The two are comapred first on their offsets, and then by name.

at(secs)

Method for creating new ActiveSupport::TimeWithZone instance in time zone of `self` from number of seconds since the Unix epoch. Example:

      Time.zone = "Hawaii"        # => "Hawaii"
      Time.utc(2000).to_f         # => 946684800.0
      Time.zone.at(946684800.0)   # => Fri, 31 Dec 1999 14:00:00 HST -10:00

formatted_offset(colon=true, alternate_utc_string = nil)

Returns the offset of this time zone as a formatted string, of the format "+HH:MM".

local(*args)

Method for creating new ActiveSupport::TimeWithZone instance in time zone of `self` from given values. Example:

      Time.zone = "Hawaii"                      # => "Hawaii"
      Time.zone.local(2007, 2, 1, 15, 30, 45)   # => Thu, 01 Feb 2007 15:30:45 HST -10:00

local_to_utc(time, dst=true)

Adjust the given time to the simultaneous time in UTC. Returns a Time.utc() instance.

now()

Returns an ActiveSupport::TimeWithZone instance representing the current time in the time zone represented by `self`. Example:

      Time.zone = 'Hawaii'  # => "Hawaii"
      Time.zone.now         # => Wed, 23 Jan 2008 20:24:27 HST -10:00

parse(str, now=now)

Method for creating new ActiveSupport::TimeWithZone instance in time zone of `self` from parsed string. Example:

      Time.zone = "Hawaii"                      # => "Hawaii"
      Time.zone.parse('1999-12-31 14:00:00')    # => Fri, 31 Dec 1999 14:00:00 HST -10:00

If upper components are missing from the string, they are supplied from TimeZone#now:

      Time.zone.now                 # => Fri, 31 Dec 1999 14:00:00 HST -10:00
      Time.zone.parse('22:30:00')   # => Fri, 31 Dec 1999 22:30:00 HST -10:00

period_for_local(time, dst=true)

Available so that TimeZone instances respond like TZInfo::Timezone instances

period_for_utc(time)

Available so that TimeZone instances respond like TZInfo::Timezone instances

to_s()

Returns a textual representation of this time zone.

today()

Return the current date in this time zone.

tzinfo()

TODO: Preload instead of lazy load for thread safety

utc_offset()
utc_to_local(time)

Adjust the given time to the simultaneous time in the time zone represented by `self`. Returns a Time.utc() instance — if you want an ActiveSupport::TimeWithZone instance, use Time#in_time_zone() instead.

[Validate]