Class: ActiveSupport::TimeZone
| Relationships & Source Files | |
| Super Chains via Extension / Inclusion / Inheritance | |
| Instance Chain: 
          self,
          Comparable
         | |
| Inherits: | Object | 
| Defined in: | activesupport/lib/active_support/values/time_zone.rb | 
Overview
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 134 zones. 
- 
Retrieve and display zones with a friendlier name (e.g., “Eastern Time (US & Canada)” instead of “America/New_York”). 
- 
Lazily load TZInfo::Timezoneinstances only when they’re needed.
- 
Create TimeWithZoneinstances via TimeZone’s #local, #parse, #at and #now methods.
If you set config.time_zone in the ::Rails Application, you can access this TimeZone object via Time.zone:
# application.rb:
class Application < Rails::Application
  config.time_zone = 'Eastern Time (US & Canada)'
end
Time.zone      # => #<ActiveSupport::TimeZone:0x514834...>
Time.zone.name # => "Eastern Time (US & Canada)"
Time.zone.now  # => Sun, 18 May 2008 14:30:44 EDT -04:00Constant Summary
- 
    MAPPING =
    # File 'activesupport/lib/active_support/values/time_zone.rb', line 31Keys are ::RailsTimeZone names, values are TZInfo identifiers.{ "International Date Line West" => "Etc/GMT+12", "Midway Island" => "Pacific/Midway", "American 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/Sao_Paulo", "Buenos Aires" => "America/Argentina/Buenos_Aires", "Montevideo" => "America/Montevideo", "Georgetown" => "America/Guyana", "Puerto Rico" => "America/Puerto_Rico", "Greenland" => "America/Godthab", "Mid-Atlantic" => "Atlantic/South_Georgia", "Azores" => "Atlantic/Azores", "Cape Verde Is." => "Atlantic/Cape_Verde", "Dublin" => "Europe/Dublin", "Edinburgh" => "Europe/London", "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/Zurich", "Zurich" => "Europe/Zurich", "Rome" => "Europe/Rome", "Stockholm" => "Europe/Stockholm", "Vienna" => "Europe/Vienna", "West Central Africa" => "Africa/Algiers", "Bucharest" => "Europe/Bucharest", "Cairo" => "Africa/Cairo", "Helsinki" => "Europe/Helsinki", "Kyiv" => "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", "Kaliningrad" => "Europe/Kaliningrad", "Moscow" => "Europe/Moscow", "St. Petersburg" => "Europe/Moscow", "Volgograd" => "Europe/Volgograd", "Samara" => "Europe/Samara", "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/Kathmandu", "Astana" => "Asia/Dhaka", "Dhaka" => "Asia/Dhaka", "Sri Jayawardenepura" => "Asia/Colombo", "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", "Ulaanbaatar" => "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", "Srednekolymsk" => "Asia/Srednekolymsk", "Solomon Is." => "Pacific/Guadalcanal", "New Caledonia" => "Pacific/Noumea", "Fiji" => "Pacific/Fiji", "Kamchatka" => "Asia/Kamchatka", "Marshall Is." => "Pacific/Majuro", "Auckland" => "Pacific/Auckland", "Wellington" => "Pacific/Auckland", "Nuku'alofa" => "Pacific/Tongatapu", "Tokelau Is." => "Pacific/Fakaofo", "Chatham Is." => "Pacific/Chatham", "Samoa" => "Pacific/Apia" }
Class Method Summary
- 
    
      .[](arg)  
    
    Locate a specific time zone object. 
- 
    
      .all  
    
    Returns an array of all TimeZoneobjects.
- 
    
      .country_zones(country_code)  
    
    A convenience method for returning a collection of TimeZoneobjects for time zones in the country specified by its ISO 3166-1 Alpha2 code.
- .create
- .find_tzinfo(name)
- 
    
      .new(name)  ⇒ TimeZone 
    
    constructor
    Returns a TimeZoneinstance with the given name, ornilif no suchTimeZoneinstance exists.
- 
    
      .seconds_to_utc_offset(seconds, colon = true)  
    
    Assumes self represents an offset from UTC in seconds (as returned from Time#utc_offset) and turns this into an +HH:MM formatted string.
- 
    
      .us_zones  
    
    A convenience method for returning a collection of TimeZoneobjects for time zones in the USA.
Instance Attribute Summary
Instance Method Summary
- 
    
      #<=>(zone)  
    
    Compare this time zone to the parameter. 
- 
    
      #=~(re)  
    
    Compare #name and TZInfo identifier to a supplied regexp, returning trueif a match is found.
- 
    
      #at(*args)  
    
    ::Methodfor creating newTimeWithZoneinstance in time zone ofselffrom number of seconds since the Unix epoch.
- 
    
      #formatted_offset(colon = true, alternate_utc_string = nil)  
    
    Returns a formatted string of the offset from UTC, or an alternative string if the time zone is already UTC. 
- 
    
      #initialize(name, utc_offset = nil, tzinfo = nil)  ⇒ TimeZone 
    
    constructor
    Create a new TimeZoneobject with the given name and offset.
- 
    
      #iso8601(str)  
    
    ::Methodfor creating newTimeWithZoneinstance in time zone ofselffrom an ISO 8601 string.
- 
    
      #local(*args)  
    
    ::Methodfor creating newTimeWithZoneinstance in time zone ofselffrom given values.
- 
    
      #local_to_utc(time, dst = true)  
    
    Adjust the given time to the simultaneous time in UTC. 
- 
    
      #match?(re)  ⇒ Boolean 
    
    Compare #name and TZInfo identifier to a supplied regexp, returning trueif a match is found.
- 
    
      #now  
    
    Returns an TimeWithZoneinstance representing the current time in the time zone represented byself.
- 
    
      #parse(str, now = now())  
    
    ::Methodfor creating newTimeWithZoneinstance in time zone ofselffrom parsed string.
- 
    
      #period_for_local(time, dst = true)  
    
    Available so that TimeZoneinstances respond likeTZInfo::Timezoneinstances.
- 
    
      #period_for_utc(time)  
    
    Available so that TimeZoneinstances respond likeTZInfo::Timezoneinstances.
- 
    
      #rfc3339(str)  
    
    ::Methodfor creating newTimeWithZoneinstance in time zone ofselffrom an RFC 3339 string.
- 
    
      #strptime(str, format, now = now())  
    
    Parses straccording toformatand returns anTimeWithZone.
- 
    
      #to_s  
    
    Returns a textual representation of this time zone. 
- 
    
      #today  
    
    Returns the current date in this time zone. 
- 
    
      #tomorrow  
    
    Returns the next date in this time zone. 
- 
    
      #utc_offset  
    
    Returns the offset of this time zone from UTC in seconds. 
- 
    
      #utc_to_local(time)  
    
    Adjust the given time to the simultaneous time in the time zone represented by self.
- 
    
      #yesterday  
    
    Returns the previous date in this time zone. 
Constructor Details
    .new(name)  ⇒ TimeZone 
  
Returns 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.)
    #initialize(name, utc_offset = nil, tzinfo = nil)  ⇒ TimeZone 
  
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).
# File 'activesupport/lib/active_support/values/time_zone.rb', line 297
def initialize(name, utc_offset = nil, tzinfo = nil) @name = name @utc_offset = utc_offset @tzinfo = tzinfo || TimeZone.find_tzinfo(name) end
Class Method Details
.[](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.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 230
def [](arg) case arg when String begin @lazy_zones_map[arg] ||= create(arg) rescue TZInfo::InvalidTimezoneIdentifier nil end when Numeric, ActiveSupport::Duration arg *= 3600 if arg.abs <= 13 all.find { |z| z.utc_offset == arg.to_i } else raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}" end end
.all
Returns 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.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 221
def all @zones ||= zones_map.values.sort end
.country_zones(country_code)
A convenience method for returning a collection of TimeZone objects for time zones in the country specified by its ISO 3166-1 Alpha2 code.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 254
def country_zones(country_code) code = country_code.to_s.upcase @country_zones[code] ||= load_country_zones(code) end
.create
[ GitHub ]# File 'activesupport/lib/active_support/values/time_zone.rb', line 209
alias_method :create, :new
.find_tzinfo(name)
[ GitHub ].seconds_to_utc_offset(seconds, colon = true)
Assumes self represents an offset from UTC in seconds (as returned from Time#utc_offset) and turns this into an +HH:MM formatted string.
ActiveSupport::TimeZone.seconds_to_utc_offset(-21_600) # => "-06:00"# File 'activesupport/lib/active_support/values/time_zone.rb', line 197
def seconds_to_utc_offset(seconds, colon = true) format = colon ? UTC_OFFSET_WITH_COLON : UTC_OFFSET_WITHOUT_COLON sign = (seconds < 0 ? "-" : "+") hours = seconds.abs / 3600 minutes = (seconds.abs % 3600) / 60 format % [sign, hours, minutes] end
.us_zones
A convenience method for returning a collection of TimeZone objects for time zones in the USA.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 248
def us_zones country_zones(:us) end
Instance Attribute Details
#name (readonly)
[ GitHub ]# File 'activesupport/lib/active_support/values/time_zone.rb', line 290
attr_reader :name
#tzinfo (readonly)
[ GitHub ]# File 'activesupport/lib/active_support/values/time_zone.rb', line 291
attr_reader :tzinfo
Instance Method Details
#<=>(zone)
Compare this time zone to the parameter. The two are compared first on their offsets, and then by name.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 320
def <=>(zone) return unless zone.respond_to? :utc_offset result = (utc_offset <=> zone.utc_offset) result = (name <=> zone.name) if result == 0 result end
#=~(re)
Compare #name and TZInfo identifier to a supplied regexp, returning true if a match is found.
#at(*args)
::Method for creating new TimeWithZone instance in time zone of self from number of seconds since the Unix epoch.
Time.zone = 'Hawaii'        # => "Hawaii"
Time.utc(2000).to_f         # => 946684800.0
Time.zone.at(946684800.0)   # => Fri, 31 Dec 1999 14:00:00 HST -10:00A second argument can be supplied to specify sub-second precision.
Time.zone = 'Hawaii'                # => "Hawaii"
Time.at(946684800, 123456.789).nsec # => 123456789# File 'activesupport/lib/active_support/values/time_zone.rb', line 366
def at(*args) Time.at(*args).utc.in_time_zone(self) end
#formatted_offset(colon = true, alternate_utc_string = nil)
Returns a formatted string of the offset from UTC, or an alternative string if the time zone is already UTC.
zone = ActiveSupport::TimeZone['Central Time (US & Canada)']
zone.formatted_offset        # => "-06:00"
zone.formatted_offset(false) # => "-0600"# File 'activesupport/lib/active_support/values/time_zone.rb', line 314
def formatted_offset(colon = true, alternate_utc_string = nil) utc_offset == 0 && alternate_utc_string || self.class.seconds_to_utc_offset(utc_offset, colon) end
#iso8601(str)
::Method for creating new TimeWithZone instance in time zone of self from an ISO 8601 string.
Time.zone = 'Hawaii'                     # => "Hawaii"
Time.zone.iso8601('1999-12-31T14:00:00') # => Fri, 31 Dec 1999 14:00:00 HST -10:00If the time components are missing then they will be set to zero.
Time.zone = 'Hawaii'            # => "Hawaii"
Time.zone.iso8601('1999-12-31') # => Fri, 31 Dec 1999 00:00:00 HST -10:00If the string is invalid then an ArgumentError will be raised unlike #parse which usually returns nil when given an invalid date string.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 383
def iso8601(str) raise ArgumentError, "invalid date" if str.nil? parts = Date._iso8601(str) raise ArgumentError, "invalid date" if parts.empty? time = Time.new( parts.fetch(:year), parts.fetch(:mon), parts.fetch(:mday), parts.fetch(:hour, 0), parts.fetch(:min, 0), parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0), parts.fetch(:offset, 0) ) if parts[:offset] TimeWithZone.new(time.utc, self) else TimeWithZone.new(nil, self, time) end end
#local(*args)
# File 'activesupport/lib/active_support/values/time_zone.rb', line 350
def local(*args) time = Time.utc(*args) ActiveSupport::TimeWithZone.new(nil, self, time) end
#local_to_utc(time, dst = true)
Adjust the given time to the simultaneous time in UTC. Returns a Time.utc() instance.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 523
def local_to_utc(time, dst = true) tzinfo.local_to_utc(time, dst) end
    #match?(re)  ⇒ Boolean 
  
Compare #name and TZInfo identifier to a supplied regexp, returning true if a match is found.
#now
Returns an TimeWithZone instance representing the current time in the time zone represented by self.
Time.zone = 'Hawaii'  # => "Hawaii"
Time.zone.now         # => Wed, 23 Jan 2008 20:24:27 HST -10:00# File 'activesupport/lib/active_support/values/time_zone.rb', line 488
def now time_now.utc.in_time_zone(self) end
#parse(str, now = now())
::Method for creating new TimeWithZone instance in time zone of self from parsed string.
Time.zone = 'Hawaii'                   # => "Hawaii"
Time.zone.parse('1999-12-31 14:00:00') # => Fri, 31 Dec 1999 14:00:00 HST -10:00If upper components are missing from the string, they are supplied from #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 -10:00However, if the date component is not provided, but any other upper components are supplied, then the day of the month defaults to 1:
Time.zone.parse('Mar 2000') # => Wed, 01 Mar 2000 00:00:00 HST -10:00If the string is invalid then an ArgumentError could be raised.
#period_for_local(time, dst = true)
Available so that TimeZone instances respond like TZInfo::Timezone instances.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 535
def period_for_local(time, dst = true) tzinfo.period_for_local(time, dst) { |periods| periods.last } end
#period_for_utc(time)
Available so that TimeZone instances respond like TZInfo::Timezone instances.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 529
def period_for_utc(time) tzinfo.period_for_utc(time) end
#rfc3339(str)
::Method for creating new TimeWithZone instance in time zone of self from an RFC 3339 string.
Time.zone = 'Hawaii'                     # => "Hawaii"
Time.zone.rfc3339('2000-01-01T00:00:00Z') # => Fri, 31 Dec 1999 14:00:00 HST -10:00If the time or zone components are missing then an ArgumentError will be raised. This is much stricter than either #parse or #iso8601 which allow for missing components.
Time.zone = 'Hawaii'            # => "Hawaii"
Time.zone.rfc3339('1999-12-31') # => ArgumentError: invalid date# File 'activesupport/lib/active_support/values/time_zone.rb', line 441
def rfc3339(str) parts = Date._rfc3339(str) raise ArgumentError, "invalid date" if parts.empty? time = Time.new( parts.fetch(:year), parts.fetch(:mon), parts.fetch(:mday), parts.fetch(:hour), parts.fetch(:min), parts.fetch(:sec) + parts.fetch(:sec_fraction, 0), parts.fetch(:offset) ) TimeWithZone.new(time.utc, self) end
#strptime(str, format, now = now())
Parses str according to format and returns an TimeWithZone.
Assumes that str is a time in the time zone self, unless format includes an explicit time zone. (This is the same behavior as #parse.) In either case, the returned TimeWithZone has the timezone of self.
Time.zone = 'Hawaii'                   # => "Hawaii"
Time.zone.strptime('1999-12-31 14:00:00', '%Y-%m-%d %H:%M:%S') # => Fri, 31 Dec 1999 14:00:00 HST -10:00If upper components are missing from the string, they are supplied from #now:
Time.zone.now                              # => Fri, 31 Dec 1999 14:00:00 HST -10:00
Time.zone.strptime('22:30:00', '%H:%M:%S') # => Fri, 31 Dec 1999 22:30:00 HST -10:00However, if the date component is not provided, but any other upper components are supplied, then the day of the month defaults to 1:
Time.zone.strptime('Mar 2000', '%b %Y') # => Wed, 01 Mar 2000 00:00:00 HST -10:00#to_s
Returns a textual representation of this time zone.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 341
def to_s "(GMT#{formatted_offset}) #{name}" end
#today
Returns the current date in this time zone.
#tomorrow
Returns the next date in this time zone.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 498
def tomorrow today + 1 end
#utc_offset
Returns the offset of this time zone from UTC in seconds.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 304
def utc_offset @utc_offset || tzinfo&.current_period&.base_utc_offset end
#utc_to_local(time)
Adjust the given time to the simultaneous time in the time zone represented by self. Returns a local time with the appropriate offset – if you want an TimeWithZone instance, use Time#in_time_zone() instead.
As of tzinfo 2, utc_to_local returns a ::Time with a non-zero utc_offset. See the ActiveSupport.utc_to_local_returns_utc_offset_times config for more info.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 514
def utc_to_local(time) tzinfo.utc_to_local(time).yield_self do |t| ActiveSupport.utc_to_local_returns_utc_offset_times ? t : Time.utc(t.year, t.month, t.day, t.hour, t.min, t.sec, t.sec_fraction) end end
#yesterday
Returns the previous date in this time zone.
# File 'activesupport/lib/active_support/values/time_zone.rb', line 503
def yesterday today - 1 end