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MooseX-Daemonize-0.15
River stage two • 9 direct dependents • 16 total dependents
3 ++
/ MooseX::Daemonize

NAME

MooseX::Daemonize - Role for daemonizing your Moose based application

VERSION

This document describes MooseX::Daemonize version 0.15

WARNING

The maintainers of this module now recommend using Daemon::Control instead.

SYNOPSIS

    package My::Daemon;
    use Moose;

    with qw(MooseX::Daemonize);

    # ... define your class ....

    after start => sub {
        my $self = shift;
        return unless $self->is_daemon;
        # your daemon code here ...
    };

    # then in your script ...

    my $daemon = My::Daemon->new_with_options();

    my ($command) = @{$daemon->extra_argv}
    defined $command || die "No command specified";

    $daemon->start   if $command eq 'start';
    $daemon->status  if $command eq 'status';
    $daemon->restart if $command eq 'restart';
    $daemon->stop    if $command eq 'stop';

    warn($daemon->status_message);
    exit($daemon->exit_code);

DESCRIPTION

Often you want to write a persistant daemon that has a pid file, and responds appropriately to Signals. This module provides a set of basic roles as an infrastructure to do that.

CAVEATS

When going into background MooseX::Daemonize closes all open file handles. This may interfere with you logging because it may also close the log file handle you want to write to. To prevent this you can either defer opening the log file until after start. Alternatively, use can use the 'dont_close_all_files' option either from the command line or in your .sh script.

Assuming you want to use Log::Log4perl for example you could expand the MooseX::Daemonize example above like this.

    after start => sub {
        my $self = shift;
        return unless $self->is_daemon;
        Log::Log4perl->init(\$log4perl_config);
        my $logger = Log::Log4perl->get_logger();
        $logger->info("Daemon started");
        # your daemon code here ...
    };

ATTRIBUTES

This list includes attributes brought in from other roles as well we include them here for ease of documentation. All of these attributes are settable though MooseX::Getopt's command line handling, with the exception of is_daemon.

progname Path::Class::Dir | Str

The name of our daemon, defaults to $package_name =~ s/::/_/;

pidbase Path::Class::Dir | Str

The base for our PID, defaults to /var/run/

pidfile MooseX::Daemonize::Pid::File | Str

The file we store our PID in, defaults to $pidbase/$progname.pid

foreground Bool

If true, the process won't background. Useful for debugging. This option can be set via Getopt's -f.

no_double_fork Bool

If true, the process will not perform the typical double-fork, which is extra added protection from your process accidentally aquiring a controlling terminal. More information can be found by Googling "double fork daemonize".

ignore_zombies Bool

If true, the process will not clean up zombie processes. Normally you don't want this.

dont_close_all_files Bool

If true, the objects open filehandles will not be closed when daemonized. Normally you don't want this.

is_daemon Bool

If true, the process is the backgrounded daemon process, if false it is the parent process. This is useful for example in an after 'start' = sub { }> block.

NOTE: This option is explicitly not available through MooseX::Getopt.

stop_timeout

Number of seconds to wait for the process to stop, before trying harder to kill it. Defaults to 2 seconds.

These are the internal attributes, which are not available through MooseX::Getopt.

exit_code Int
status_message Str

METHODS

Daemon Control Methods

These methods can be used to control the daemon behavior. Every effort has been made to have these methods DWIM (Do What I Mean), so that you can focus on just writing the code for your daemon.

Extending these methods is best done with the Moose method modifiers, such as before, after and around.

start

Setup a pidfile, fork, then setup the signal handlers.

stop

Stop the process matching the pidfile, and unlinks the pidfile.

restart

Literally this is:

    $self->stop();
    $self->start();
status
shutdown

Pidfile Handling Methods

init_pidfile

This method will create a MooseX::Daemonize::Pid::File object and tell it to store the PID in the file $pidbase/$progname.pid.

check

This checks to see if the daemon process is currently running by checking the pidfile.

get_pid

Returns the PID of the daemon process.

save_pid

Write the pidfile.

remove_pid

Removes the pidfile.

Signal Handling Methods

setup_signals

Setup the signal handlers, by default it only sets up handlers for SIGINT and SIGHUP. If you wish to add more signals just use the after method modifier and add them.

handle_sigint

Handle a INT signal, by default calls $self-stop()>

handle_sighup

Handle a HUP signal. By default calls $self-restart()>

Exit Code Methods

These are overriable constant methods used for setting the exit code.

OK

Returns 0.

ERROR

Returns 1.

Introspection

meta()

The meta() method from Class::MOP::Class

DEPENDENCIES

Moose, MooseX::Getopt, MooseX::Types::Path::Class and POSIX

INCOMPATIBILITIES

None reported. Although obviously this will not work on Windows.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to bug-acme-dahut-call@rt.cpan.org, or through the web interface at http://rt.cpan.org.

SEE ALSO

Daemon::Control, Proc::Daemon, Daemon::Generic

AUTHORS

Chris Prather <chris@prather.org

Stevan Little <stevan.little@iinteractive.com>

THANKS

Mike Boyko, Matt S. Trout, Stevan Little, Brandon Black, Ash Berlin and the #moose denzians

Some bug fixes sponsored by Takkle Inc.

LICENCE AND COPYRIGHT

Copyright (c) 2007-2011, Chris Prather <chris@prather.org>. Some rights reserved.

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

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.