cron2ical.rb

cron2ical.rb

# coding: utf-8

=begin
# cron2ical.rb

## install
    $ wget https://gist.github.com/.../raw/.../cron2ical.rb
    $ gem install icalendar chrono

## setting
edit CalTitle and MaxDate.

## usage
    $ crontab -l | ruby cron2ical.rb > foobar.ical
=end

require 'icalendar' 
require 'chrono'
require 'date'

# settings
CalTitle = 'crontab'
MaxDate = Date.today >> 1

Event = Struct.new :time, :source

src   = readlines.reject{|i| /^\s*#/ =~ i || i.split(/\s+/).count < 6}
crons = src.map{|line| Chrono::Iterator.new line.strip}
cals = []
crons.each do |i|
  begin
    while i.now < MaxDate
      cals << Event.new(i.next, i.source)
    end
  rescue 
  end
end
cals.sort_by!{|i| i.time }


cal = Icalendar::Calendar.new
cal.timezone do |t|
  t.tzid = 'Asia/Tokyo'
  t.standard do |s|
    s.tzoffsetfrom = '+0900'
    s.tzoffsetto   = '+0900'
    s.tzname       = 'JST'
    s.dtstart      = '19700101T000000'
  end
end
cal.append_custom_property 'X-WR-CALNAME;VALUE=TEXT', CalTitle

cals.each do |i|
  cal.event do |e|
    e.summary     = i.source.split(/\s+/)[5]
    e.description = i.source
    e.dtstart     = Icalendar::Values::DateTime.new i.time
    e.dtend       = Icalendar::Values::DateTime.new i.time + 60
  end
end
cal.publish

puts cal.to_ical