NAME¶

DateTime::Event::Cron - DateTime extension for generating recurrence sets from crontab lines and files.

SYNOPSIS¶

  use DateTime::Event::Cron;
  # check if a date matches (defaults to current time)
  my $c = DateTime::Event::Cron->new('* 2 * * *');
  if ($c->match) {
    # do stuff
  }
  if ($c->match($date)) {
    # do something else for datetime $date
  }
  # DateTime::Set construction from crontab line
  $crontab = '*/3 15 1-10 3,4,5 */2';
  $set = DateTime::Event::Cron->from_cron($crontab);
  $iter = $set->iterator(after => DateTime->now);
  while (1) {
    my $next = $iter->next;
    my $now  = DateTime->now;
    sleep(($next->subtract_datetime_absolute($now))->seconds);
    # do stuff...
  }
  # List of DateTime::Set objects from crontab file
  @sets = DateTime::Event::Cron->from_crontab(file => '/etc/crontab');
  $now = DateTime->now;
  print "Now: ", $now->datetime, "\n";
  foreach (@sets) {
    my $next = $_->next($now);
    print $next->datetime, "\n";
  }
  # DateTime::Set parameters
  $crontab = '* * * * *';
  $now = DateTime->now;
  %set_parms = ( after => $now );
  $set = DateTime::Event::Cron->from_cron(cron => $crontab, %set_parms);
  $dt = $set->next;
  print "Now: ", $now->datetime, " and next: ", $dt->datetime, "\n";
  # Spans for DateTime::Set
  $crontab = '* * * * *';
  $now = DateTime->now;
  $now2 = $now->clone;
  $span = DateTime::Span->from_datetimes(
            start => $now->add(minutes => 1),
            end   => $now2->add(hours => 1),
          );
  %parms = (cron => $crontab, span => $span);
  $set = DateTime::Event::Cron->from_cron(%parms);
  # ...do things with the DateTime::Set
  # Every RTFCT relative to 12am Jan 1st this year
  $crontab = '7-10 6,12-15 10-28/2 */3 3,4,5';
  $date = DateTime->now->truncate(to => 'year');
  $set = DateTime::Event::Cron->from_cron(cron => $crontab, after => $date);
  # Rather than generating DateTime::Set objects, next/prev
  # calculations can be made directly:
  # Every day at 10am, 2pm, and 6pm. Reference date
  # defaults to DateTime->now.
  $crontab = '10,14,18 * * * *';
  $dtc = DateTime::Event::Cron->new_from_cron(cron => $crontab);
  $next_datetime = $dtc->next;
  $last_datetime = $dtc->previous;
  ...
  # List of DateTime::Event::Cron objects from
  # crontab file
  @dtc = DateTime::Event::Cron->new_from_crontab(file => '/etc/crontab');
  # Full cron lines with user, such as from /etc/crontab
  # or files in /etc/cron.d, are supported and auto-detected:
  $crontab = '* * * * * gump /bin/date';
  $dtc = DateTime::Event::Cron->new(cron => $crontab);
  # Auto-detection of users is disabled if you explicitly
  # enable/disable via the user_mode parameter:
  $dtc = DateTime::Event::Cron->new(cron => $crontab, user_mode => 1);
  my $user = $dtc->user;
  my $command = $dtc->command;
  # Unparsed original cron entry
  my $original = $dtc->original;

DESCRIPTION¶

DateTime::Event::Cron generated DateTime events or DateTime::Set objects based on crontab-style entries.

METHODS¶

The cron fields are typical crontab-style entries. For more information, see crontab(5) and extensions described in Set::Crontab. The fields can be passed as a single string or as a reference to an array containing each field. Only the first five fields are retained.

AUTHOR¶

Matthew P. Sisk <sisk@mojotoad.com>

COPYRIGHT¶

Copyright (c) 2003 Matthew P. Sisk. All rights reserved. All wrongs revenged. This program is free software; you can distribute it and/or modify it under the same terms as Perl itself.

SEE ALSO¶

DateTime(3), DateTime::Set(3), DateTime::Event::Recurrence(3), DateTime::Event::ICal(3), DateTime::Span(3), Set::Crontab(3), crontab(5)