This is a Ruby library for dealing with iCalendar files. Rather than explaining myself, here is the introduction from RFC-2445, which defines the format:
The use of calendaring and scheduling has grown considerably in the last decade. Enterprise and inter-enterprise business has become dependent on rapid scheduling of events and actions using this information technology. However, the longer term growth of calendaring and scheduling, is currently limited by the lack of Internet standards for the message content types that are central to these knowledgeware applications. This memo is intended to progress the level of interoperability possible between dissimilar calendaring and scheduling applications. This memo defines a MIME content type for exchanging electronic calendaring and scheduling information. The Internet Calendaring and Scheduling Core Object Specification, or iCalendar, allows for the capture and exchange of information normally stored within a calendaring and scheduling application; such as a Personal Information Manager (PIM) or a Group Scheduling product.
The iCalendar format is suitable as an exchange format between applications or systems. The format is defined in terms of a MIME content type. This will enable the object to be exchanged using several transports, including but not limited to SMTP, HTTP, a file system, desktop interactive protocols such as the use of a memory- based clipboard or drag/drop interactions, point-to-point asynchronous communication, wired-network transport, or some form of unwired transport such as infrared might also be used.
require 'rubygems' # Unless you install from the tarball or zip. require 'icalendar' require 'date' include Icalendar # Probably do this in your class to limit namespace overlap
# Create a calendar with an event (standard method) cal = Calendar.new cal.event do dtstart Date.new(2005, 04, 29) dtend Date.new(2005, 04, 28) summary "Meeting with the man." description "Have a long lunch meeting and decide nothing..." klass "PRIVATE" end cal.publish
event = Event.new event.start = DateTime.civil(2006, 6, 23, 8, 30) event.summary = "A great event!" cal.add_event(event) event2 = cal.event # This automatically adds the event to the calendar event2.start = DateTime.civil(2006, 6, 24, 8, 30) event2.summary = "Another great event!" # Now with support for property parameters params = {"ALTREP" =>['"http://my.language.net"'], "LANGUAGE" => ["SPANISH"]} cal.event do dtstart Date.new(2005, 04, 29) dtend Date.new(2005, 04, 28) summary "This is a summary with params.", params end # We can output the calendar as a string to write to a file, # network port, database etc. cal_string = cal.to_ical puts cal_string
cal.event.do
# ...other event properties
alarm do
action "EMAIL"
description "This is an event reminder" # email body (required)
summary "Alarm notification" # email subject (required)
attendees %w(mailto:me@my-domain.com mailto:me-too@my-domain.com) # one or more email recipients (required)
add_attendee "mailto:me-three@my-domain.com"
remove_attendee "mailto:me@my-domain.com"
trigger "-PT15M" # 15 minutes before
add_attach "ftp://host.com/novo-procs/felizano.exe", {"FMTTYPE" => "application/binary"} # email attachments (optional)
end
alarm do
action "DISPLAY" # This line isn't necessary, it's the default
summary "Alarm notification"
trigger "-P1DT0H0M0S" # 1 day before
end
alarm do
action "AUDIO"
trigger "-PT15M"
add_attach "Basso", {"VALUE" => ["URI"]} # only one attach allowed (optional)
end
end
# Output
# BEGIN:VALARM
# ACTION:EMAIL
# ATTACH;FMTTYPE=application/binary:ftp://host.com/novo-procs/felizano.exe
# TRIGGER:-PT15M
# SUMMARY:Alarm notification
# DESCRIPTION:This is an event reminder
# ATTENDEE:mailto:me-too@my-domain.com
# ATTENDEE:mailto:me-three@my-domain.com
# END:VALARM
#
# BEGIN:VALARM
# ACTION:DISPLAY
# TRIGGER:-P1DT0H0M0S
# SUMMARY:Alarm notification
# END:VALARM
#
# BEGIN:VALARM
# ACTION:AUDIO
# ATTACH;VALUE=URI:Basso
# TRIGGER:-PT15M
# END:VALARM
# Create a timezone definition (previous convention) cal = Calendar.new timezone = Icalendar::Timezone.new daylight = Icalendar::Daylight.new standard = Icalendar::Standard.new timezone.timezone_id = "America/Chicago" daylight.timezone_offset_from = "-0600" daylight.timezone_offset_to = "-0500" daylight.timezone_name = "CDT" daylight.dtstart = "19700308TO20000" daylight.recurrence_rules = ["FREQ=YEARLY;BYMONTH=3;BYDAY=2SU"] standard.timezone_offset_from = "-0500" standard.timezone_offset_to = "-0600" standard.timezone_name = "CST" standard.dtstart = "19701101T020000" standard.recurrence_rules = ["YEARLY;BYMONTH=11;BYDAY=1SU"] timezone.add(daylight) timezone.add(standard) cal.add(timezone) # Now, you can make timezones like this cal = Calendar.new cal.timezone do timezone_id "America/Chicago" daylight do timezone_offset_from "-0600" timezone_offset_to "-0500" timezone_name "CDT" dtstart "19700308TO20000" add_recurrence_rule "FREQ=YEARLY;BYMONTH=3;BYDAY=2SU" end standard do timezone_offset_from "-0500" timezone_offset_to "-0600" timezone_name "CST" dtstart "19701101T020000" add_recurrence_rule "YEARLY;BYMONTH=11;BYDAY=1SU" end end # Both conventions output # BEGIN:VTIMEZONE # TZID:America/Chicago # BEGIN:DAYLIGHT # TZOFFSETFROM:-0600 # TZOFFSETTO:-0500 # TZNAME:CDT # DTSTART:19700308T020000 # RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU # END:DAYLIGHT # BEGIN:STANDARD # TZOFFSETFROM:-0500 # TZOFFSETTO:-0600 # TZNAME:CST # DTSTART:19701101T020000 # RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU # END:STANDARD # END:VTIMEZONE
Add ‘$KCODE = ’u’‘ to make icalender work correctly with Utf8 texts
# Open a file or pass a string to the parser cal_file = File.open("single_event.ics") # Parser returns an array of calendars because a single file # can have multiple calendars. cals = Icalendar.parse(cal_file) cal = cals.first # Now you can access the cal object in just the same way I created it event = cal.events.first puts "start date-time: " + event.dtstart puts "summary: " + event.summary
Often times in web apps and other interactive applications you’ll need to lookup items in a calendar to make changes or get details. Now you can find everything by the unique id automatically associated with all components.
cal = Calendar.new 10.times { cal.event } # Create 10 events with only default data. some_event = cal.events[5] # Grab it from the array of events # Use the uid as the key in your app key = some_event.uid # so later you can find it. same_event = cal.find_event(key)
Check the unit tests for examples of most things you’ll want to do, but please send me example code or let me know what’s missing.
The latest release version of this library can be found at
Documentation can be found at
It’s all about rubygems:
$ sudo gem install icalendar
This library is released under the same license as Ruby itself.
The iCalendar library homepage is icalendar.rubyforge.org/
There is an icalendar-devel@rubyforge.org mailing list that can be used for asking questions, making comments or submitting patches.