NAME
    AnyEvent::DateTime::Cron - AnyEvent crontab with DateTime::Event::Cron

SYNOPSIS
        AnyEvent::DateTime::Cron->new()
            ->add(
                '* * * * *'   => sub { warn "Every minute"},
                '*/2 * * * *' => sub { warn "Every second minute"},
              )
            ->start
            ->recv

        $cron = AnyEvent::DateTime::Cron->new();
        $cron->debug(1)->add(
            {
                cron => '* * * * *',
                cb   => sub {'foo'},
                name => 'job_name_for_debugging'
            },
            {...}.
        );

        $cron->delete($job_id,$job_id...)

        $cv = $cron->start;
        $cv->recv;

DESCRIPTION
    AnyEvent::DateTime::Cron is an AnyEvent based crontab, which supports
    all crontab formats recognised by DateTime::Event::Cron.

    It allows you to shut down a running instance gracefully, by waiting for
    any running cron jobs to finish before exiting.

METHODS
  new()
        $cron = AnyEvent::DateTime::Cron->new();

    Creates a new AnyEvent::DateTime::Cron instance - takes no parameters.

  add()
        $cron->add(
            '* * * * *'     => sub {...},
            {
                cron => '* * * * *',
                cb   => sub {...},
                name => 'my_job'
            }
        );

    Use "add()" to add new cron jobs. It accepts a list of crontab entries
    and callbacks, or alternatively, a list of hashrefs with named
    parameters. The latter allows you to pass in an optional "name"
    parameter, which can be useful for debugging.

    Each new job is assigned an ID.

    New jobs can be added before running, or while running.

    See "CALLBACKS" for more.

  delete()
        $cron->delete($job_id,$job_id,....)

    Delete one or more existing jobs, before starting or while running.

  start()
        my $cv = $cron->start;
        $cv->recv;

    Schedules all jobs to start at the next scheduled time, and returns an
    AnyEvent condvar
    <http://metacpan.org/module/AnyEvent#CONDITION-VARIABLES>.

    The cron loop can be started by calling "recv()" on the condvar.

  stop()
        $cron->stop()

    Used to shutdown the cron loop gracefully. You can also shutdown the
    cron loop by sending a "HUP" signal to the process.

  jobs()
        $job = $cron->jobs

    Returns a hashref containing all the current cron jobs.

  debug()
        $cron->debug(1|0)

    Turn on debugging.

CALLBACKS
    A callback is a coderef (eg an anonymous subroutine) which will be
    called every time your job is triggered. Callbacks should use "AnyEvent"
    themselves, so that they run asynchronously, otherwise they can block
    the execution of the cron loop, delaying other jobs.

    Two parameters are passed to your callback: the main $cv of the cron
    loop, and the $job_description which contains various details about the
    current job.

    The $cv is the most important parameter, as it allows you to control how
    your cron loop will shut down. If your callback doesn't use "AnyEvent"
    and is blocking, then your callback will complete before it returns to
    the cron loop.

    However, if your callback is running asynchronously (and it really
    should), then you can block the cron loop from responding to a "stop()"
    request until your job has completed:

        sub {
            my $cv = shift;
            $cv->begin;
            do_something_asynchronous( cb => sub { $cv->end })
        }

    Callbacks are called inside an "eval" so if they throw an error, they
    will warn, but won't cause the cron loop to exit.

AUTHOR
    Clinton Gormley, "<drtech at cpan.org>"

BUGS
    If you have any suggestions for improvements, or find any bugs, please
    report them to
    <http://github.com/clintongormley/AnyEvent-DateTime-Cron/issues>. I will
    be notified, and then you'll automatically be notified of progress on
    your bug as I make changes.

SUPPORT
    You can find documentation for this module with the perldoc command.

        perldoc AnyEvent::DateTime::Cron

    You can also look for information at
    <http://github.com/clintongormley/AnyEvent-DateTime-Cron>

LICENSE AND COPYRIGHT
    Copyright 2011 Clinton Gormley.

    This program is free software; you can redistribute it and/or modify it
    under the terms of either: the GNU General Public License as published
    by the Free Software Foundation; or the Artistic License.

    See http://dev.perl.org/licenses/ for more information.