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class ActiveSupport::TimeZone
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::Timezone instances only when they're needed.
Create ActiveSupport::TimeWithZone instances via TimeZone's
local
,parse
,at
andnow
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 -04:00
Constants
- MAPPING
-
Keys are Rails TimeZone names, values are TZInfo identifiers.
- UTC_OFFSET_WITHOUT_COLON
- UTC_OFFSET_WITH_COLON
Attributes
Public Class Methods
# 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
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 254
def country_zones(country_code)
code = country_code.to_s.upcase
@country_zones[code] ||= load_country_zones(code)
end
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 205
def find_tzinfo(name)
TZInfo::Timezone.new(MAPPING[name] || name)
end
# File activesupport/lib/active_support/values/time_zone.rb, line 214
def new(name)
self[name]
end
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.)
# 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
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 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
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 248
def us_zones
country_zones(:us)
end
A convenience method for returning a collection of TimeZone objects for time zones in the USA.
Public Instance Methods
# File activesupport/lib/active_support/values/time_zone.rb, line 324
def <=>(zone)
return unless zone.respond_to? :utc_offset
result = (utc_offset <=> zone.utc_offset)
result = (name <=> zone.name) if result == 0
result
end
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 333
def =~(re)
re === name || re === MAPPING[name]
end
Compare name and TZInfo identifier to a supplied regexp, returning true
if a match is found.
# File activesupport/lib/active_support/values/time_zone.rb, line 358
def at(secs)
Time.at(secs).utc.in_time_zone(self)
end
Method for creating new ActiveSupport::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 -10:00
# File activesupport/lib/active_support/values/time_zone.rb, line 318
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
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 375
def iso8601(str)
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
Method for creating new ActiveSupport::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 -10:00
If 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 -10:00
If 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 347
def local(*args)
time = Time.utc(*args)
ActiveSupport::TimeWithZone.new(nil, self, time)
end
Method for creating new ActiveSupport::TimeWithZone instance in time zone of self
from given values.
Time.zone = 'Hawaii' # => "Hawaii"
Time.zone.local(2007, 2, 1, 15, 30, 45) # => Thu, 01 Feb 2007 15:30:45 HST -10:00
# File activesupport/lib/active_support/values/time_zone.rb, line 506
def local_to_utc(time, dst = true)
tzinfo.local_to_utc(time, dst)
end
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 478
def now
time_now.utc.in_time_zone(self)
end
Returns an ActiveSupport::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 415
def parse(str, now = now())
parts_to_time(Date._parse(str, false), now)
end
Method for creating new ActiveSupport::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 -10:00
If 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 -10:00
However, 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 -10:00
If the string is invalid then an ArgumentError
could be raised.
# File activesupport/lib/active_support/values/time_zone.rb, line 518
def period_for_local(time, dst = true)
tzinfo.period_for_local(time, dst) { |periods| periods.last }
end
Available so that TimeZone instances respond like TZInfo::Timezone instances.
# File activesupport/lib/active_support/values/time_zone.rb, line 512
def period_for_utc(time)
tzinfo.period_for_utc(time)
end
Available so that TimeZone instances respond like TZInfo::Timezone instances.
# File activesupport/lib/active_support/values/time_zone.rb, line 431
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
Method for creating new ActiveSupport::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 -10:00
If 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 469
def strptime(str, format, now = now())
parts_to_time(DateTime._strptime(str, format), now)
end
Parses str
according to format
and returns an ActiveSupport::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 -10:00
If 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 -10:00
However, 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
# File activesupport/lib/active_support/values/time_zone.rb, line 338
def to_s
"(GMT#{formatted_offset}) #{name}"
end
Returns a textual representation of this time zone.
# File activesupport/lib/active_support/values/time_zone.rb, line 483
def today
tzinfo.now.to_date
end
Returns the current date in this time zone.
# File activesupport/lib/active_support/values/time_zone.rb, line 488
def tomorrow
today + 1
end
Returns the next date in this time zone.
# File activesupport/lib/active_support/values/time_zone.rb, line 304
def utc_offset
if @utc_offset
@utc_offset
else
tzinfo.current_period.utc_offset if tzinfo && tzinfo.current_period
end
end
Returns the offset of this time zone from UTC in seconds.
# File activesupport/lib/active_support/values/time_zone.rb, line 500
def utc_to_local(time)
tzinfo.utc_to_local(time)
end
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 DateAndTime::Zones#in_time_zone instead.
# File activesupport/lib/active_support/values/time_zone.rb, line 493
def yesterday
today - 1
end
Returns the previous date in this time zone.
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.