Parses date as date-time defined by RFC 2822 and converts it to a Time object. The format is identical to the date format defined by RFC 822 and updated by RFC 1123.

ArgumentError is raised if date is not compliant with RFC 2822 or Time class cannot represent specified date.

See #rfc2822 for more information on this format.

Source Code

# File time.rb, line 261
def rfc2822(date)
  if /\A\s*
      (?:(?:Mon|Tue|Wed|Thu|Fri|Sat|Sun)\s*,\s*)?
      (\d{1,2})\s+
      (Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\s+
      (\d{2,})\s+
      (\d{2})\s*
      :\s*(\d{2})\s*
      (?::\s*(\d{2}))?\s+
      ([+-]\d{4}|
       UT|GMT|EST|EDT|CST|CDT|MST|MDT|PST|PDT|[A-IK-Z])/ix =~ date
    # Since RFC 2822 permit comments, the regexp has no right anchor.
    day = $1.to_i
    mon = MonthValue[$2.upcase]
    year = $3.to_i
    hour = $4.to_i
    min = $5.to_i
    sec = $6 ? $6.to_i : 0
    zone = $7

    # following year completion is compliant with RFC 2822.
    year = if year < 50
             2000 + year
           elsif year < 1000
             1900 + year
           else
             year
           end

    year, mon, day, hour, min, sec =
      apply_offset(year, mon, day, hour, min, sec, zone_offset(zone))
    t = self.utc(year, mon, day, hour, min, sec)
    t.localtime if !zone_utc?(zone)
    t
  else
    raise ArgumentError.new("not RFC 2822 compliant date: #{date.inspect}")
  end
end