Class: TZInfo::Timezone
- Inherits:
-
Object
- Object
- TZInfo::Timezone
- Includes:
- Comparable
- Defined in:
- lib/tzinfo/timezone.rb
Overview
Timezone is the base class of all timezones. It provides a factory method get to access timezones by identifier. Once a specific Timezone has been retrieved, DateTimes, Times and timestamps can be converted between the UTC and the local time for the zone. For example:
tz = TZInfo::Timezone.get('America/New_York')
puts tz.utc_to_local(DateTime.new(2005,8,29,15,35,0)).to_s
puts tz.local_to_utc(Time.utc(2005,8,29,11,35,0)).to_s
puts tz.utc_to_local(1125315300).to_s
Each time conversion method returns an object of the same type it was passed.
The timezone information all comes from the tz database (see www.twinsun.com/tz/tz-link.htm)
Direct Known Subclasses
Constant Summary collapse
- @@loaded_zones =
Cache of loaded zones by identifier to avoid using require if a zone has already been loaded.
{}
- @@index_loaded =
Whether the timezones index has been loaded yet.
false
Class Method Summary collapse
-
._load(data) ⇒ Object
Loads a marshalled Timezone.
-
.all ⇒ Object
Returns an array containing all the available Timezones.
-
.all_country_zone_identifiers ⇒ Object
Returns all the zone identifiers defined for all Countries.
-
.all_country_zones ⇒ Object
Returns all the Timezones defined for all Countries.
-
.all_data_zone_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones that are based on data (are not links to other Timezones)..
-
.all_data_zones ⇒ Object
Returns an array containing all the available Timezones that are based on data (are not links to other Timezones).
-
.all_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones.
-
.all_linked_zone_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones that are links to other Timezones.
-
.all_linked_zones ⇒ Object
Returns an array containing all the available Timezones that are links to other Timezones.
-
.get(identifier) ⇒ Object
Returns a timezone by its identifier (e.g. “Europe/London”, “America/Chicago” or “UTC”).
-
.get_proxy(identifier) ⇒ Object
Returns a proxy for the Timezone with the given identifier.
-
.new(identifier = nil) ⇒ Object
If identifier is nil calls super(), otherwise calls get.
-
.us_zone_identifiers ⇒ Object
Returns all US zone identifiers.
-
.us_zones ⇒ Object
Returns all US Timezone instances.
Instance Method Summary collapse
-
#<=>(tz) ⇒ Object
Compares two Timezones based on their identifier.
-
#_dump(limit) ⇒ Object
Dumps this Timezone for marshalling.
-
#current_period ⇒ Object
Returns the TimezonePeriod for the current time.
-
#current_period_and_time ⇒ Object
(also: #current_time_and_period)
Returns the current Time and TimezonePeriod as an array.
-
#eql?(tz) ⇒ Boolean
Returns true if and only if the identifier of tz is equal to the identifier of this Timezone.
-
#friendly_identifier(skip_first_part = false) ⇒ Object
Returns a friendlier version of the identifier.
-
#hash ⇒ Object
Returns a hash of this Timezone.
-
#identifier ⇒ Object
The identifier of the timezone, e.g.
-
#inspect ⇒ Object
Returns internal object state as a programmer-readable string.
-
#local_to_utc(local, dst = nil) ⇒ Object
Converts a time in the local timezone to UTC.
-
#name ⇒ Object
An alias for identifier.
-
#now ⇒ Object
Returns the current time in the timezone as a Time.
-
#period_for_local(local, dst = nil) ⇒ Object
Returns the TimezonePeriod for the given local time.
-
#period_for_utc(utc) ⇒ Object
Returns the TimezonePeriod for the given UTC time.
-
#periods_for_local(local) ⇒ Object
Returns the set of TimezonePeriod instances that are valid for the given local time as an array.
-
#strftime(format, utc = Time.now.utc) ⇒ Object
Converts a time in UTC to local time and returns it as a string according to the given format.
-
#to_s ⇒ Object
Returns a friendlier version of the identifier.
-
#utc_to_local(utc) ⇒ Object
Converts a time in UTC to the local timezone.
Class Method Details
._load(data) ⇒ Object
Loads a marshalled Timezone.
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# File 'lib/tzinfo/timezone.rb', line 486 def self._load(data) Timezone.get(data) end |
.all ⇒ Object
Returns an array containing all the available Timezones.
Returns TimezoneProxy objects to avoid the overhead of loading Timezone definitions until a conversion is actually required.
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# File 'lib/tzinfo/timezone.rb', line 135 def self.all get_proxies(all_identifiers) end |
.all_country_zone_identifiers ⇒ Object
Returns all the zone identifiers defined for all Countries. This is not the complete set of zone identifiers as some are not country specific (e.g. ‘Etc/GMT’). You can obtain a Timezone instance for a given identifier with the get method.
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# File 'lib/tzinfo/timezone.rb', line 194 def self.all_country_zone_identifiers Country.all_codes.inject([]) {|zones,country| zones += Country.get(country).zone_identifiers } end |
.all_country_zones ⇒ Object
Returns all the Timezones defined for all Countries. This is not the complete set of Timezones as some are not country specific (e.g. ‘Etc/GMT’).
Returns TimezoneProxy objects to avoid the overhead of loading Timezone definitions until a conversion is actually required.
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# File 'lib/tzinfo/timezone.rb', line 184 def self.all_country_zones Country.all_codes.inject([]) {|zones,country| zones += Country.get(country).zones } end |
.all_data_zone_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones that are based on data (are not links to other Timezones)..
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# File 'lib/tzinfo/timezone.rb', line 157 def self.all_data_zone_identifiers load_index Indexes::Timezones.data_timezones end |
.all_data_zones ⇒ Object
Returns an array containing all the available Timezones that are based on data (are not links to other Timezones).
Returns TimezoneProxy objects to avoid the overhead of loading Timezone definitions until a conversion is actually required.
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# File 'lib/tzinfo/timezone.rb', line 151 def self.all_data_zones get_proxies(all_data_zone_identifiers) end |
.all_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones.
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# File 'lib/tzinfo/timezone.rb', line 141 def self.all_identifiers load_index Indexes::Timezones.timezones end |
.all_linked_zone_identifiers ⇒ Object
Returns an array containing the identifiers of all the available Timezones that are links to other Timezones.
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# File 'lib/tzinfo/timezone.rb', line 173 def self.all_linked_zone_identifiers load_index Indexes::Timezones.linked_timezones end |
.all_linked_zones ⇒ Object
Returns an array containing all the available Timezones that are links to other Timezones.
Returns TimezoneProxy objects to avoid the overhead of loading Timezone definitions until a conversion is actually required.
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# File 'lib/tzinfo/timezone.rb', line 167 def self.all_linked_zones get_proxies(all_linked_zone_identifiers) end |
.get(identifier) ⇒ Object
Returns a timezone by its identifier (e.g. “Europe/London”, “America/Chicago” or “UTC”).
Raises InvalidTimezoneIdentifier if the timezone couldn’t be found.
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# File 'lib/tzinfo/timezone.rb', line 75 def self.get(identifier) instance = @@loaded_zones[identifier] unless instance raise InvalidTimezoneIdentifier, 'Invalid identifier' if identifier !~ /^[A-Za-z0-9\+\-_]+(\/[A-Za-z0-9\+\-_]+)*$/ identifier = identifier.gsub(/-/, '__m__').gsub(/\+/, '__p__') begin # Use a temporary variable to avoid an rdoc warning file = "tzinfo/definitions/#{identifier}".untaint require file m = Definitions identifier.split(/\//).each {|part| m = m.const_get(part) } info = m.get # Could make Timezone subclasses register an interest in an info # type. Since there are currently only two however, there isn't # much point. if info.kind_of?(DataTimezoneInfo) instance = DataTimezone.new(info) elsif info.kind_of?(LinkedTimezoneInfo) instance = LinkedTimezone.new(info) else raise InvalidTimezoneIdentifier, "No handler for info type #{info.class}" end @@loaded_zones[instance.identifier] = instance rescue LoadError, NameError => e raise InvalidTimezoneIdentifier, e. end end instance end |
.get_proxy(identifier) ⇒ Object
Returns a proxy for the Timezone with the given identifier. The proxy will cause the real timezone to be loaded when an attempt is made to find a period or convert a time. get_proxy will not validate the identifier. If an invalid identifier is specified, no exception will be raised until the proxy is used.
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# File 'lib/tzinfo/timezone.rb', line 117 def self.get_proxy(identifier) TimezoneProxy.new(identifier) end |
.new(identifier = nil) ⇒ Object
If identifier is nil calls super(), otherwise calls get. An identfier should always be passed in when called externally.
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# File 'lib/tzinfo/timezone.rb', line 123 def self.new(identifier = nil) if identifier get(identifier) else super() end end |
.us_zone_identifiers ⇒ Object
Returns all US zone identifiers. A shortcut for TZInfo::Country.get(‘US’).zone_identifiers.
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# File 'lib/tzinfo/timezone.rb', line 211 def self.us_zone_identifiers Country.get('US').zone_identifiers end |
.us_zones ⇒ Object
Returns all US Timezone instances. A shortcut for TZInfo::Country.get(‘US’).zones.
Returns TimezoneProxy objects to avoid the overhead of loading Timezone definitions until a conversion is actually required.
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# File 'lib/tzinfo/timezone.rb', line 205 def self.us_zones Country.get('US').zones end |
Instance Method Details
#<=>(tz) ⇒ Object
Compares two Timezones based on their identifier. Returns -1 if tz is less than self, 0 if tz is equal to self and +1 if tz is greater than self.
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# File 'lib/tzinfo/timezone.rb', line 465 def <=>(tz) identifier <=> tz.identifier end |
#_dump(limit) ⇒ Object
Dumps this Timezone for marshalling.
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# File 'lib/tzinfo/timezone.rb', line 481 def _dump(limit) identifier end |
#current_period ⇒ Object
Returns the TimezonePeriod for the current time.
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# File 'lib/tzinfo/timezone.rb', line 427 def current_period period_for_utc(Time.now.utc) end |
#current_period_and_time ⇒ Object Also known as: current_time_and_period
Returns the current Time and TimezonePeriod as an array. The first element is the time, the second element is the period.
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# File 'lib/tzinfo/timezone.rb', line 433 def current_period_and_time utc = Time.now.utc period = period_for_utc(utc) [period.to_local(utc), period] end |
#eql?(tz) ⇒ Boolean
Returns true if and only if the identifier of tz is equal to the identifier of this Timezone.
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# File 'lib/tzinfo/timezone.rb', line 471 def eql?(tz) self == tz end |
#friendly_identifier(skip_first_part = false) ⇒ Object
Returns a friendlier version of the identifier. Set skip_first_part to omit the first part of the identifier (typically a region name) where there is more than one part.
For example:
Timezone.get('Europe/Paris').friendly_identifier(false) #=> "Europe - Paris"
Timezone.get('Europe/Paris').friendly_identifier(true) #=> "Paris"
Timezone.get('America/Indiana/Knox').friendly_identifier(false) #=> "America - Knox, Indiana"
Timezone.get('America/Indiana/Knox').friendly_identifier(true) #=> "Knox, Indiana"
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# File 'lib/tzinfo/timezone.rb', line 246 def friendly_identifier(skip_first_part = false) parts = identifier.split('/') if parts.empty? # shouldn't happen identifier elsif parts.length == 1 parts[0] else if skip_first_part result = '' else result = parts[0] + ' - ' end parts[1, parts.length - 1].reverse_each {|part| part.gsub!(/_/, ' ') if part.index(/[a-z]/) # Missing a space if a lower case followed by an upper case and the # name isn't McXxxx. part.gsub!(/([^M][a-z])([A-Z])/, '\1 \2') part.gsub!(/([M][a-bd-z])([A-Z])/, '\1 \2') # Missing an apostrophe if two consecutive upper case characters. part.gsub!(/([A-Z])([A-Z])/, '\1\'\2') end result << part result << ', ' } result.slice!(result.length - 2, 2) result end end |
#hash ⇒ Object
Returns a hash of this Timezone.
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# File 'lib/tzinfo/timezone.rb', line 476 def hash identifier.hash end |
#identifier ⇒ Object
The identifier of the timezone, e.g. “Europe/Paris”.
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# File 'lib/tzinfo/timezone.rb', line 216 def identifier raise UnknownTimezone, 'TZInfo::Timezone constructed directly' end |
#inspect ⇒ Object
Returns internal object state as a programmer-readable string.
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# File 'lib/tzinfo/timezone.rb', line 232 def inspect "#<#{self.class}: #{identifier}>" end |
#local_to_utc(local, dst = nil) ⇒ Object
Converts a time in the local timezone to UTC. local can either be a DateTime, Time or timestamp (Time.to_i). The returned time has the same type as local. Any timezone information in local is ignored (it is treated as a local time).
Warning: There are local times that have no equivalent UTC times (e.g. in the transition from standard time to daylight savings time). There are also local times that have more than one UTC equivalent (e.g. in the transition from daylight savings time to standard time).
In the first case (no equivalent UTC time), a PeriodNotFound exception will be raised.
In the second case (more than one equivalent UTC time), an AmbiguousTime exception will be raised unless the optional dst parameter or block handles the ambiguity.
If the ambiguity is due to a transition from daylight savings time to standard time, the dst parameter can be used to select whether the daylight savings time or local time is used. For example,
Timezone.get('America/New_York').local_to_utc(DateTime.new(2004,10,31,1,30,0))
would raise an AmbiguousTime exception.
Specifying dst=true would return 2004-10-31 5:30:00. Specifying dst=false would return 2004-10-31 6:30:00.
If the dst parameter does not resolve the ambiguity, and a block is specified, it is called. The block must take a single parameter - an array of the periods that need to be resolved. The block can return a single period to use to convert the time or return nil or an empty array to cause an AmbiguousTime exception to be raised.
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# File 'lib/tzinfo/timezone.rb', line 409 def local_to_utc(local, dst = nil) TimeOrDateTime.wrap(local) {|wrapped| if block_given? period = period_for_local(wrapped, dst) {|periods| yield periods } else period = period_for_local(wrapped, dst) end period.to_utc(wrapped) } end |
#name ⇒ Object
An alias for identifier.
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# File 'lib/tzinfo/timezone.rb', line 221 def name # Don't use alias, as identifier gets overridden. identifier end |
#now ⇒ Object
Returns the current time in the timezone as a Time.
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# File 'lib/tzinfo/timezone.rb', line 422 def now utc_to_local(Time.now.utc) end |
#period_for_local(local, dst = nil) ⇒ Object
Returns the TimezonePeriod for the given local time. local can either be a DateTime, Time or integer timestamp (Time.to_i). Any timezone information in local is ignored (it is treated as a time in the current timezone).
Warning: There are local times that have no equivalent UTC times (e.g. in the transition from standard time to daylight savings time). There are also local times that have more than one UTC equivalent (e.g. in the transition from daylight savings time to standard time).
In the first case (no equivalent UTC time), a PeriodNotFound exception will be raised.
In the second case (more than one equivalent UTC time), an AmbiguousTime exception will be raised unless the optional dst parameter or block handles the ambiguity.
If the ambiguity is due to a transition from daylight savings time to standard time, the dst parameter can be used to select whether the daylight savings time or local time is used. For example,
Timezone.get('America/New_York').period_for_local(DateTime.new(2004,10,31,1,30,0))
would raise an AmbiguousTime exception.
Specifying dst=true would the daylight savings period from April to October 2004. Specifying dst=false would return the standard period from October 2004 to April 2005.
If the dst parameter does not resolve the ambiguity, and a block is specified, it is called. The block must take a single parameter - an array of the periods that need to be resolved. The block can select and return a single period or return nil or an empty array to cause an AmbiguousTime exception to be raised.
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# File 'lib/tzinfo/timezone.rb', line 331 def period_for_local(local, dst = nil) results = periods_for_local(local) if results.empty? raise PeriodNotFound elsif results.size < 2 results.first else # ambiguous result try to resolve if !dst.nil? matches = results.find_all {|period| period.dst? == dst} results = matches if !matches.empty? end if results.size < 2 results.first else # still ambiguous, try the block if block_given? results = yield results end if results.is_a?(TimezonePeriod) results elsif results && results.size == 1 results.first else raise AmbiguousTime, "#{local} is an ambiguous local time." end end end end |
#period_for_utc(utc) ⇒ Object
Returns the TimezonePeriod for the given UTC time. utc can either be a DateTime, Time or integer timestamp (Time.to_i). Any timezone information in utc is ignored (it is treated as a UTC time).
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# File 'lib/tzinfo/timezone.rb', line 285 def period_for_utc(utc) raise UnknownTimezone, 'TZInfo::Timezone constructed directly' end |
#periods_for_local(local) ⇒ Object
Returns the set of TimezonePeriod instances that are valid for the given local time as an array. If you just want a single period, use period_for_local instead and specify how ambiguities should be resolved. Returns an empty array if no periods are found for the given time.
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# File 'lib/tzinfo/timezone.rb', line 293 def periods_for_local(local) raise UnknownTimezone, 'TZInfo::Timezone constructed directly' end |
#strftime(format, utc = Time.now.utc) ⇒ Object
Converts a time in UTC to local time and returns it as a string according to the given format. The formatting is identical to Time.strftime and DateTime.strftime, except %Z is replaced with the timezone abbreviation for the specified time (for example, EST or EDT).
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# File 'lib/tzinfo/timezone.rb', line 445 def strftime(format, utc = Time.now.utc) period = period_for_utc(utc) local = period.to_local(utc) local = Time.at(local).utc unless local.kind_of?(Time) || local.kind_of?(DateTime) abbreviation = period.abbreviation.to_s.gsub(/%/, '%%') format = format.gsub(/(.?)%Z/) do if $1 == '%' # return %%Z so the real strftime treats it as a literal %Z too '%%Z' else "#$1#{abbreviation}" end end local.strftime(format) end |
#to_s ⇒ Object
Returns a friendlier version of the identifier.
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# File 'lib/tzinfo/timezone.rb', line 227 def to_s friendly_identifier end |
#utc_to_local(utc) ⇒ Object
Converts a time in UTC to the local timezone. utc can either be a DateTime, Time or timestamp (Time.to_i). The returned time has the same type as utc. Any timezone information in utc is ignored (it is treated as a UTC time).
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# File 'lib/tzinfo/timezone.rb', line 370 def utc_to_local(utc) TimeOrDateTime.wrap(utc) {|wrapped| period_for_utc(wrapped).to_local(wrapped) } end |