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class DateTime

Parent:: Object
Included modules:: DateAndTime::Compatibility

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 69
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 10
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 204
def <=>(other)
  if other.respond_to? :to_datetime
    super other.to_datetime rescue nil
  else
    super
  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 8
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 13
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 78
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 105
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 118
def beginning_of_day
  change(hour: 0)
end

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

Also aliased as: midnight, at_midnight, at_beginning_of_day

beginning_of_hour() Show source

# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 142
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 154
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 51
def change(options)
  if new_nsec = options[:nsec]
    raise ArgumentError, "Can't change both :nsec and :usec at the same time: #{options.inspect}" if options[:usec]
    new_fraction = Rational(new_nsec, 1000000000)
  else
    new_usec = options.fetch(:usec, (options[:hour] || options[:min] || options[:sec]) ? 0 : Rational(nsec, 1000))
    new_fraction = Rational(new_usec, 1000000)
  end

  raise ArgumentError, "argument out of range" if new_fraction >= 1

  ::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) + new_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 136
def end_of_day
  change(hour: 23, min: 59, sec: 59, usec: Rational(999999999, 1000))
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 148
def end_of_hour
  change(min: 59, sec: 59, usec: Rational(999999999, 1000))
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 160
def end_of_minute
  change(sec: 59, usec: Rational(999999999, 1000))
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 51
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.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.

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 166
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 126
def middle_of_day
  change(hour: 12)
end

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

Also aliased as: midday, noon, at_midday, at_noon, at_middle_of_day

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 94
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 56
def readable_inspect
  to_formatted_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 20
def seconds_since_midnight
  sec + (min * 60) + (hour * 3600)
end

Returns the number of seconds since 00:00:00.

DateTime.new(2012, 8, 29,  0,  0,  0).seconds_since_midnight # => 0
DateTime.new(2012, 8, 29, 12, 34, 56).seconds_since_midnight # => 45296
DateTime.new(2012, 8, 29, 23, 59, 59).seconds_since_midnight # => 86399

seconds_until_end_of_day() Show source

# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 29
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 112
def since(seconds)
  self + Rational(seconds, 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 36
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_f() Show source

# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 79
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 35
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_fs.

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_fs(:db)                     # => "2007-12-04 00:00:00"
datetime.to_formatted_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_fs

to_fs(format = :default)

Alias for: to_formatted_s

to_i() Show source

# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 84
def to_i
  seconds_since_unix_epoch.to_i
end

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

to_time() Show source

# File activesupport/lib/active_support/core_ext/date_time/compatibility.rb, line 15
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 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 89
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 180
def utc
  utc = new_offset(0)

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

Returns a Time 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 193
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 198
def utc_offset
  (offset * 86400).to_i
end

Returns the offset value in seconds.

class DateTime

Examples

Adding your own datetime formats to to_formatted_s

Adding your own datetime formats to `to_formatted_s`