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

VERSION
    version 0.05

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(
            '* * * * *', name   => 'job_name', single => 1,  sub {'foo'},
            ...
        );

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

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

        AnyEvent::DateTime::Cron->new(time_zone => 'local');
            ->add(
                '* * * * *'   => sub { warn "Every minute"},
                '*/2 * * * *' => sub { warn "Every second minute"},
              )
            ->start
            ->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(
            time_zone => ...
            quartz    => 0/1
        );

    Creates a new AnyEvent::DateTime::Cron instance - takes optional
    parameters time_zone and quartz.

    time_zone can will be used to set the time_zone for any DateTime objects
    that are used internally.

    if quartz is set to a true value then this class will use switch to
    using DateTime::Event::Cron::Quartz internally, which will allow the use
    of seconds in the cron expression. See the DateTime::Event::Cron::Quartz
    for details on writing a proper quartz cron expression.

  add()
        $cron->add(
            '* * * * *',                                     sub {...},
            '* * * * *', name   => 'job_name', single => 1,  sub {...},
            ...
        );

    Use "add()" to add new cron jobs. It accepts a list of crontab entries,
    optional paremeters and callbacks.

    The "name" parameter is useful for debugging, otherwise the
    auto-assigned "ID" is used instead.

    The "single" parameter, if "true", will only allow a single instance of
    a job to run at any one time.

    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 "TERM" 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.

AUTHORS
    *   Clinton Gormley <drtech@cpan.org>

    *   Andy Gorman <agorman@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2013 by Clinton Gormley.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.