iCal::Parser - Parse iCalendar files into a data structure

       Rick Frankel, cpan@rickster.com

       This program is free software; you can redistribute it and/or modify it under  the  same  terms  as  Perl
       itself.

       The full text of the license can be found in the LICENSE file included with this module.

       This module processes iCalendar (vCalendar 2.0) files as specified in RFC 2445 into a data structure.  It
       handles recurrences ("RRULE"s), exclusions ("EXDATE"s), event updates (events with a "RECURRENCE-ID"),
       and nested data structures ("ATTENDEES" and "VALARM"s). It currently ignores the "VTIMEZONE", "VJOURNAL"
       and "VFREEBUSY" entry types.

       The data structure returned is a hash like the following:

           {
             calendars=>[\%cal, ...],
             events=>{yyyy=>{mm=>{dd}=>{UID=>\%event}}
             todos=>[\%todo, ...]
           }

       That is, it contains an array of calendar hashes, a hash of events key by "year=>month=>day=>eventUID",
       and an array of todos.

       Calendars, events and todos are "rolled up" version os the hashes returned from Text::vFile::asData, with
       dates replaced by "DateTime" objects.

       During parsing, events in the input calendar are expanded out into multiple events, one per day covered
       by the event, as follows:

       •   If  the  event  is a one day "all day" event (in ical, the event is 24hrs long, starts at midnight on
           the day and ends a midnight of the next day), it contains no "hour" field and the "allday"  field  is
           set to 1.

       •   If  the  event  is  a  recurrence  ("RRULE"),  one  event  per  day  is  created  as  per the "RRULE"
           specification.

       •   If the event spans more than one day (the start and end dates are on different  days,  but  does  not
           contain  an  "RRULE"),  it  is  expanded  into  multiple  events, the first events end time is set to
           midnight, subsequent events are set to start at midnight and end at midnight the following day  (same
           as  an "allday" event, but the "allday" field is not set), and the last days event is set to run from
           midnight to the end time of the original multi-day event.

       •   If the event is an update (it contains a "RECURRENCE-ID"), the original  event  is  updated.  If  the
           referenced event does not exist (e.g., it was deleted after the update), then the event is added as a
           new event.

       An example of each hash is below.

   CalendarHash
           {
               'X-WR-CALNAME' => 'Test',
               'index' => 1,
               'X-WR-RELCALID' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
               'PRODID' => '-//Apple Computer\\, Inc//iCal 1.5//EN',
               'CALSCALE' => 'GREGORIAN',
               'X-WR-TIMEZONE' => 'America/New_York',
               'X-WR-CALDESC' => 'My Test Calendar',
               'VERSION' => '2.0'
           }

   EventHash
       Note that "hours" and "allday" are mutually exclusive in the actual data.  The "idref" field contains the
       "id"  of  the  calendar  the  event  came  from,  which  is  useful if the hash was created from multiple
       calendars.

           {
               'SUMMARY' => 'overnight',
               'hours' => '15.00',
               'allday' => 1,
               'UID' => '95CCBF98-3685-11D9-8CA5-000D93C45D90',
               'idref' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
               'DTSTAMP' => \%DateTime,
               'DTEND' => \%DateTime,
               'DTSTART' => \%DateTime
               'ATTENDEE' => [
                  {
                     'CN' => 'Jay',
                     'value' => 'mailto:jayl@my.server'
                  },
                 ],
                 'VALARM' => [
                   {
                     'when' => \%DateTime,
                     'SUMMARY' => 'Alarm notification',
                     'ACTION' => 'EMAIL',
                     'DESCRIPTION' => 'This is an event reminder',
                     'ATTENDEE' => [
                        {
                          'value' => 'mailto:cpan@my.server'
                        }
                     ]
                  }
                ],
           }

   TodoHash
           {
               'URL' => 'mailto:me',
               'SUMMARY' => 'todo 1',
               'UID' => 'B78E68F2-35E7-11D9-9E64-000D93C45D90',
               'idref' => '7CCE8555-3516-11D9-8A43-000D93C45D90',
               'STATUS' => 'COMPLETED',
               'COMPLETED' => \%DateTime,
               'DTSTAMP' => \%DateTime,
               'PRIORITY' => '9',
               'DTSTART' => \%DateTime,
               'DUE' => \%DateTime,
               'DESCRIPTION' => 'not much',
               'VALARM' => [
                  {
                     'when' => \%DateTime,
                     'ATTACH' => 'file://localhost/my-file',
                     'ACTION' => 'PROCEDURE'
                  }
               ],
           },

new(%opt_args)OptionalArguments

       start {yyymmdd|DateTime}
           Only include events on or after "yyymmdd". Defaults to Jan of this year.

       end {yyyymmdd|DateTime}
           Only include events before "yyymmdd".

       no_events
           Don't include events in the output (todos only).

       no_todos
           Don't include todos in the output (events only).

       months n
           DateTime::Sets (used for calculating recurrences) are limited to approximately  200  entries.  If  an
           "end"  date  is  not  specified, the "to" date is set to the "start" date plus this many months.  The
           default is 60.

       tz (string|DateTime::TimeZone)
           Use tz as timezone for date values.  The default is 'local', which will adjust the  parsed  dates  to
           the current timezone.

       debug
           Set to non-zero for some debugging output during processing.

   parse({file|file_handle}+)
       Parse the input files or opened file handles and return the generated hash.

       This  function  can  be  called  mutitple times and the calendars will be merge into the hash, each event
       tagged with the unique id of its calendar.

   parse_files({file|file_handle}+)
       Alias for parse()

   parse_strings(string+)
       Parse the input strings (each assumed to be a valid iCalendar) and return the generated hash.

       iCal::Parser - Parse iCalendar files into a data structure

       Text::vFile::asData, DateTime::Set, DateTime::Span, iCal::Parser::SAX

perl v5.40.1                                       2025-03-01                                  iCal::Parser(3pm)

         use iCal::Parser;

         my $parser=iCal::Parser->new();
         my $hash=$parser->parse($file);

         $parser->parse($another_file);
         my $combined=$parser->calendar;

         my $combined=iCal::Parser->new->parse(@files);
         my $combined=iCal::Parser->new->parse_files(@files);
         my $combined=iCal::Parser->new->parse_strings(@strings);