class DateTime

Parent:
Object
Included modules:
DateAndTime::Compatibility, DateAndTime::Zones

Public Class Methods

civil_from_format(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0) Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 65
def self.civil_from_format(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0)
  if utc_or_local.to_sym == :local
    offset = ::Time.local(year, month, day).utc_offset.to_r / 86400
  else
    offset = 0
  end
  civil(year, month, day, hour, min, sec, offset)
end

Returns DateTime with local offset for given year if format is local else offset is zero.

DateTime.civil_from_format :local, 2012
# => Sun, 01 Jan 2012 00:00:00 +0300
DateTime.civil_from_format :local, 2012, 12, 17
# => Mon, 17 Dec 2012 00:00:00 +0000
current() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 8
def current
  ::Time.zone ? ::Time.zone.now.to_datetime : ::Time.now.to_datetime
end

Returns Time.zone.now.to_datetime when Time.zone or config.time_zone are set, otherwise returns Time.now.to_datetime.

Public Instance Methods

<=>(other) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 183
def <=>(other)
  if other.kind_of?(Infinity)
    super
  elsif other.respond_to? :to_datetime
    super other.to_datetime rescue nil
  else
    nil
  end
end

Layers additional behavior on DateTime#<=> so that Time and ActiveSupport::TimeWithZone instances can be compared with a DateTime.

Calls superclass method
acts_like_date?() Show source
# File activesupport/lib/active_support/core_ext/date_time/acts_like.rb, line 6
def acts_like_date?
  true
end

Duck-types as a Date-like class. See Object#acts_like?.

acts_like_time?() Show source
# File activesupport/lib/active_support/core_ext/date_time/acts_like.rb, line 11
def acts_like_time?
  true
end

Duck-types as a Time-like class. See Object#acts_like?.

advance(options) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 62
def advance(options)
  unless options[:weeks].nil?
    options[:weeks], partial_weeks = options[:weeks].divmod(1)
    options[:days] = options.fetch(:days, 0) + 7 * partial_weeks
  end

  unless options[:days].nil?
    options[:days], partial_days = options[:days].divmod(1)
    options[:hours] = options.fetch(:hours, 0) + 24 * partial_days
  end

  d = to_date.advance(options)
  datetime_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
  seconds_to_advance =        options.fetch(:seconds, 0) +
    options.fetch(:minutes, 0) * 60 +
    options.fetch(:hours, 0) * 3600

  if seconds_to_advance.zero?
    datetime_advanced_by_date
  else
    datetime_advanced_by_date.since(seconds_to_advance)
  end
end

Uses Date to provide precise Time calculations for years, months, and days. The options parameter takes a hash with any of these keys: :years, :months, :weeks, :days, :hours, :minutes, :seconds.

ago(seconds) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 89
def ago(seconds)
  since(-seconds)
end

Returns a new DateTime representing the time a number of seconds ago. Do not use this method in combination with x.months, use months_ago instead!

at_beginning_of_day()
Alias for: beginning_of_day
at_beginning_of_hour()
Alias for: beginning_of_hour
at_beginning_of_minute()
Alias for: beginning_of_minute
at_end_of_day()
Alias for: end_of_day
at_end_of_hour()
Alias for: end_of_hour
at_end_of_minute()
Alias for: end_of_minute
at_midday()
Alias for: middle_of_day
at_middle_of_day()
Alias for: middle_of_day
at_midnight()
Alias for: beginning_of_day
at_noon()
Alias for: middle_of_day
beginning_of_day() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 102
def beginning_of_day
  change(:hour => 0)
end

Returns a new DateTime representing the start of the day (0:00).

beginning_of_hour() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 126
def beginning_of_hour
  change(:min => 0)
end

Returns a new DateTime representing the start of the hour (hh:00:00).

Also aliased as: at_beginning_of_hour
beginning_of_minute() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 138
def beginning_of_minute
  change(:sec => 0)
end

Returns a new DateTime representing the start of the minute (hh:mm:00).

Also aliased as: at_beginning_of_minute
change(options) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 45
def change(options)
  ::DateTime.civil(
    options.fetch(:year, year),
    options.fetch(:month, month),
    options.fetch(:day, day),
    options.fetch(:hour, hour),
    options.fetch(:min, options[:hour] ? 0 : min),
    options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec + sec_fraction),
    options.fetch(:offset, offset),
    options.fetch(:start, start)
  )
end

Returns a new DateTime where one or more of the elements have been changed according to the options parameter. The time options (:hour, :min, :sec) reset cascadingly, so if only the hour is passed, then minute and sec is set to 0. If the hour and minute is passed, then sec is set to 0. The options parameter takes a hash with any of these keys: :year, :month, :day, :hour, :min, :sec, :offset, :start.

DateTime.new(2012, 8, 29, 22, 35, 0).change(day: 1)              # => DateTime.new(2012, 8, 1, 22, 35, 0)
DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1)  # => DateTime.new(1981, 8, 1, 22, 35, 0)
DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => DateTime.new(1981, 8, 29, 0, 0, 0)
default_inspect()
Alias for: inspect
end_of_day() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 120
def end_of_day
  change(:hour => 23, :min => 59, :sec => 59)
end

Returns a new DateTime representing the end of the day (23:59:59).

Also aliased as: at_end_of_day
end_of_hour() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 132
def end_of_hour
  change(:min => 59, :sec => 59)
end

Returns a new DateTime representing the end of the hour (hh:59:59).

Also aliased as: at_end_of_hour
end_of_minute() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 144
def end_of_minute
  change(:sec => 59)
end

Returns a new DateTime representing the end of the minute (hh:mm:59).

Also aliased as: at_end_of_minute
formatted_offset(colon = true, alternate_utc_string = nil) Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 47
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
end

datetime = DateTime.civil(2000, 1, 1, 0, 0, 0, Rational(-6, 24)) datetime.formatted_offset # => “-06:00” datetime.formatted_offset(false) # => “-0600”

getgm()
Alias for: utc
getlocal(utc_offset = nil)
Alias for: localtime
getutc()
Alias for: utc
gmtime()
Alias for: utc
in(seconds)
Alias for: since
inspect()
Also aliased as: default_inspect
Alias for: readable_inspect
localtime(utc_offset = nil) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 150
def localtime(utc_offset = nil)
  utc = new_offset(0)

  Time.utc(
    utc.year, utc.month, utc.day,
    utc.hour, utc.min, utc.sec + utc.sec_fraction
  ).getlocal(utc_offset)
end

Returns a Time instance of the simultaneous time in the system timezone.

Also aliased as: getlocal
midday()
Alias for: middle_of_day
middle_of_day() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 110
def middle_of_day
  change(:hour => 12)
end

Returns a new DateTime representing the middle of the day (12:00)

midnight()
Alias for: beginning_of_day
noon()
Alias for: middle_of_day
nsec() Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 90
def nsec
  (sec_fraction * 1_000_000_000).to_i
end

Returns the fraction of a second as nanoseconds

readable_inspect() Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 52
def readable_inspect
  to_s(:rfc822)
end

Overrides the default inspect method with a human readable one, e.g., “Mon, 21 Feb 2005 14:30:00 +0000”.

Also aliased as: inspect
seconds_since_midnight() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 14
def seconds_since_midnight
  sec + (min * 60) + (hour * 3600)
end

Seconds since midnight: DateTime.now.seconds_since_midnight.

seconds_until_end_of_day() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 23
def seconds_until_end_of_day
  end_of_day.to_i - to_i
end

Returns the number of seconds until 23:59:59.

DateTime.new(2012, 8, 29,  0,  0,  0).seconds_until_end_of_day # => 86399
DateTime.new(2012, 8, 29, 12, 34, 56).seconds_until_end_of_day # => 41103
DateTime.new(2012, 8, 29, 23, 59, 59).seconds_until_end_of_day # => 0
since(seconds) Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 96
def since(seconds)
  self + Rational(seconds.round, 86400)
end

Returns a new DateTime representing the time a number of seconds since the instance time. Do not use this method in combination with x.months, use months_since instead!

Also aliased as: in
subsec() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 30
def subsec
  sec_fraction
end

Returns the fraction of a second as a Rational

DateTime.new(2012, 8, 29, 0, 0, 0.5).subsec # => (1/2)
to_default_s(format = :default)
Alias for: to_s
to_f() Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 75
def to_f
  seconds_since_unix_epoch.to_f + sec_fraction
end

Converts self to a floating-point number of seconds, including fractional microseconds, since the Unix epoch.

to_formatted_s(format = :default) Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 33
def to_formatted_s(format = :default)
  if formatter = ::Time::DATE_FORMATS[format]
    formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
  else
    to_default_s
  end
end

Convert to a formatted string. See Time::DATE_FORMATS for predefined formats.

This method is aliased to to_s.

Examples

datetime = DateTime.civil(2007, 12, 4, 0, 0, 0, 0)   # => Tue, 04 Dec 2007 00:00:00 +0000

datetime.to_formatted_s(:db)            # => "2007-12-04 00:00:00"
datetime.to_s(:db)                      # => "2007-12-04 00:00:00"
datetime.to_s(:number)                  # => "20071204000000"
datetime.to_formatted_s(:short)         # => "04 Dec 00:00"
datetime.to_formatted_s(:long)          # => "December 04, 2007 00:00"
datetime.to_formatted_s(:long_ordinal)  # => "December 4th, 2007 00:00"
datetime.to_formatted_s(:rfc822)        # => "Tue, 04 Dec 2007 00:00:00 +0000"
datetime.to_formatted_s(:iso8601)       # => "2007-12-04T00:00:00+00:00"

Adding your own datetime formats to #to_formatted_s

DateTime formats are shared with Time. You can add your own to the Time::DATE_FORMATS hash. Use the format name as the hash key and either a strftime string or Proc instance that takes a time or datetime argument as the value.

# config/initializers/time_formats.rb
Time::DATE_FORMATS[:month_and_year] = '%B %Y'
Time::DATE_FORMATS[:short_ordinal] = lambda { |time| time.strftime("%B #{time.day.ordinalize}") }
Also aliased as: to_s
to_i() Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 80
def to_i
  seconds_since_unix_epoch.to_i
end

Converts self to an integer number of seconds since the Unix epoch.

to_s(format = :default)
Also aliased as: to_default_s
Alias for: to_formatted_s
to_time() Show source
# File activesupport/lib/active_support/core_ext/date_time/compatibility.rb, line 13
def to_time
  preserve_timezone ? getlocal(utc_offset) : getlocal
end

Either return an instance of `Time` with the same UTC offset as self or an instance of `Time` representing the same time in the the local system timezone depending on the setting of on the setting of ActiveSupport.to_time_preserves_timezone.

usec() Show source
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 85
def usec
  (sec_fraction * 1_000_000).to_i
end

Returns the fraction of a second as microseconds

utc() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 164
def utc
  new_offset(0)
end

Returns a DateTime instance of the simultaneous time in the UTC timezone.

DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24))     # => Mon, 21 Feb 2005 10:11:12 -0600
DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24)).utc # => Mon, 21 Feb 2005 16:11:12 UTC
Also aliased as: getgm, getutc, gmtime
utc?() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 172
def utc?
  offset == 0
end

Returns true if offset == 0.

utc_offset() Show source
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 177
def utc_offset
  (offset * 86400).to_i
end

Returns the offset value in seconds.

© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.