minor nit: add newline to pidfile contents, so "cat /var/run/foo.pid" output is saner

[gitmo/MooseX-Daemonize.git] / lib / MooseX / Daemonize / Pid / File.pm

package MooseX::Daemonize::Pid::File;
use strict;    # because Kwalitee is pedantic
use Moose;
use Moose::Util::TypeConstraints;

our $VERSION = '0.01';

use MooseX::Types::Path::Class;
use MooseX::Getopt::OptionTypeMap;

# NOTE:
# set up some basic coercions
# that will come in handy
# - SL
coerce 'MooseX::Daemonize::Pid::File' 
    => from 'Str' 
        => via { MooseX::Daemonize::Pid::File->new( file => $_ ) }
    => from 'ArrayRef' 
        => via { MooseX::Daemonize::Pid::File->new( file => $_ ) }        
    => from 'Path::Class::File' 
        => via { MooseX::Daemonize::Pid::File->new( file => $_ ) };
 
# NOTE:
# make sure this class plays 
# well with MooseX::Getopt
# - SL
MooseX::Getopt::OptionTypeMap->add_option_type_to_map(
    'MooseX::Daemonize::Pid::File' => '=s',
);

extends 'MooseX::Daemonize::Pid';

has '+pid' => (
    default => sub { 
        my $self = shift;
        $self->does_file_exist
            ? $self->file->slurp(chomp => 1)
            : $$
    }
);

has 'file' => (
    is       => 'ro',
    isa      => 'Path::Class::File',
    coerce   => 1,
    required => 1,
    handles  => [ 'remove' ]
);

sub does_file_exist { -s (shift)->file }

sub write {
    my $self = shift;
    my $fh = $self->file->openw;
    $fh->print($self->pid . "\n");
    $fh->close;
}

override 'is_running' => sub {
    return 0 unless (shift)->does_file_exist;
    super();
};

1;

__END__

=pod

=head1 NAME

MooseX::Daemonize::Pid::File - PID file management for MooseX::Daemonize
     
=head1 DESCRIPTION

This object extends L<MooseX::Daemonize::Pid> to add persistence in a Pidfile.

This class sets up some basic coercion routines for itself so that it can 
be created from a I<Str> (a file name), I<ArrayRef> (an array of path components
for a filename) or a I<Path::Class::File> object. 

This class registers it's type with L<MooseX::Getopt> as well, and is expected
to be passed on the command line as a string (which will then go through the 
coercion routines mentioned above).

=head1 ATTRIBUTES

=over

=item I<pid Int>

This is inherited from L<MooseX:Daemonize::Pid> and extended here to 
get it's default value from the Pidfile (if available).

=item I<file Path::Class::File | Str>

=back

=head1 METHODS 

=over

=item B<clear_pid>

=item B<has_pid>

Both of these methods are inherited from L<MooseX:Daemonize::Pid> see that 
module for more information.

=item B<remove>

This removes the Pidfile.

=item B<write>

This writes the Pidfile.

=item B<does_file_exist>

This checks if the Pidfile exists.

=item B<is_running>

This checks if the Pidfile exists, if it does it checks to see if the process
is running, if the Pidfile doesn't exist, it returns false.

=item meta()

The C<meta()> method from L<Class::MOP::Class>

=back

=head1 DEPENDENCIES

Obviously L<Moose>

=head1 INCOMPATIBILITIES

None reported.

=head1 BUGS AND LIMITATIONS

No bugs have been reported.

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

=head1 AUTHOR

Stevan Little  C<< <stevan.little@iinteractive.com> >>

=head1 LICENCE AND COPYRIGHT

Copyright (c) 2007, Chris Prather C<< <perigrin@cpan.org> >>. All rights 
reserved.

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


=head1 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.

=cut