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

package MooseX::Daemonize;
use strict;    # because Kwalitee is pedantic
use Moose::Role;

our $VERSION = 0.01;
use Carp;
use Proc::Daemon;

use File::Flock;
use File::Slurp;

with qw(MooseX::Getopt);

has progname => (
    isa      => 'Str',
    is       => 'ro',
    lazy     => 1,
    required => 1,
    default  => sub {
        ( my $name = lc $_[0]->meta->name ) =~ s/::/_/g;
        return $name;
    },
);

has pidbase => (
    isa => 'Str',
    is  => 'ro',

    #    required => 1,
    lazy    => 1,
    default => sub { return '/var/run' },
);

has pidfile => (
    isa      => 'Str',
    is       => 'ro',
    lazy     => 1,
    required => 1,
    default  => sub {
        die 'Cannot write to ' . $_[0]->pidbase unless -w $_[0]->pidbase;
        $_[0]->pidbase . '/' . $_[0]->progname . '.pid';
    },
);

has foreground => (
    metaclass   => 'Getopt',
    cmd_aliases => ['f'],
    isa         => 'Bool',
    is          => 'ro',
    default     => sub { 0 },
);

sub check {
    my ($self) = @_;
    if ( my $pid = $self->get_pid ) {
        my $prog = $self->progname;
        if ( CORE::kill 0 => $pid ) {
            croak "$prog already running ($pid).";
        }
        carp "$prog not running but found pid ($pid)."
          . "Perhaps the pid file (@{ [$self->pidfile] }) is stale?";
        return 1;
    }
    return 0;
}

sub daemonize {
    my ($self) = @_;
    Proc::Daemon::Init;
}

sub start {
    my ($self) = @_;
    return if $self->check;

    $self->daemonize unless $self->foreground;

    # Avoid 'stdin reopened for output' warning with newer perls
    open( NULL, '/dev/null' );
    <NULL> if (0);

    $self->save_pid;
    $self->setup_signals;
    return $$;
}

sub save_pid {
    my ($self) = @_;
    my $pidfile = $self->pidfile;
    lock( $pidfile, undef, 'nonblocking' )
      or croak "Could not lock PID file $pidfile: $!";
    write_file( $pidfile, "$$\n" );
    unlock($pidfile);
    return;
}

sub remove_pid {
    my ($self) = @_;
    my $pidfile = $self->pidfile;
    lock( $pidfile, undef, 'nonblocking' )
      or croak "Could not lock PID file $pidfile: $!";
    unlink($pidfile);
    unlock($pidfile);
    return;
}

sub get_pid {
    my ($self) = @_;
    my $pidfile = $self->pidfile;
    return unless -e $pidfile;
    chomp( my $pid = read_file($pidfile) );
    return $pid;
}

sub stop {
    my ( $self, %args ) = @_;
    my $pid = $self->get_pid;
    $self->kill($pid) unless $self->foreground();
    $self->remove_pid;
    return 1 if $args{no_exit};
    exit;
}

sub restart {
    my ($self) = @_;
    $self->stop( noexit => 1 );
    $self->start();
}

sub setup_signals {
    my ($self) = @_;
    $SIG{INT} = sub { $self->handle_sigint; };
    $SIG{HUP} = sub { $self->handle_sighup };
}

sub handle_sigint { $_[0]->stop; }
sub handle_sighup { $_[0]->restart; }

sub kill {
    my ( $self, $pid ) = @_;
    return unless $pid;
    unless ( CORE::kill 0 => $pid ) {

        # warn "$pid already appears dead.";
        return;
    }

    if ( $pid eq $$ ) {

        # warn "$pid is us! Can't commit suicied.";
        return;
    }

    CORE::kill( 2, $pid );    # Try SIGINT
    sleep(2) if CORE::kill( 0, $pid );

    unless ( CORE::kill 0 => $pid or $!{EPERM} ) {    # IF it is still running
        CORE::kill( 15, $pid );                       # try SIGTERM
        sleep(2) if CORE::kill( 0, $pid );
    }

    unless ( CORE::kill 0 => $pid or $!{EPERM} ) {    # IF it is still running
        CORE::kill( 9, $pid );                        # finally try SIGKILL
        sleep(2) if CORE::kill( 0, $pid );
    }

    unless ( CORE::kill 0 => $pid or $!{EPERM} ) {    # IF it is still running
        carp "$pid doesn't seem to want to die.";     # AHH EVIL DEAD!
    }

    return;
}

1;
__END__

=head1 NAME

MooseX::Daemonize - provides a Role that daemonizes your Moose based application.


=head1 VERSION

This document describes MooseX::Daemonize version 0.0.1


=head1 SYNOPSIS

    package FileMaker;
    use Moose;
    with qw(MooseX::Daemonize);

    sub create_file {
        my ( $self, $file ) = @_;
        open( FILE, ">$file" ) || die;
        close(FILE);
    }

    no Moose;

    # then in the main package ... 
    
    my $daemon = FileMaker->new();
    $daemon->start();
    $daemon->create_file($file);
    $daemon->stop();
     
=head1 DESCRIPTION

Often you want to write a persistant daemon that has a pid file, and responds appropriately to Signals. 
This module helps provide the basic infrastructure to do that.

=head1 ATTRIBUTES

=over

=item progname Str

The name of our daemon, defaults to $0

=item pidbase Str

The base for our bid, defaults to /var/run/$progname

=item pidfile Str

The file we store our PID in, defaults to /var/run/$progname/ 

=item foreground Bool

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

=back

=head1 METHODS 

=over

=item check()

Check to see if an instance is already running.

=item start()

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

=item stop()

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

=item restart()

Litterally 

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

=item daemonize()

Calls C<Proc::Daemon::Init> to daemonize this process. 

=item kill($pid)

Kills the process for $pid. This will try SIGINT, and SIGTERM before falling back to SIGKILL and finally giving up.

=item setup_signals()

Setup the signal handlers, by default it only sets up handlers for SIGINT and SIGHUP

=item handle_sigint()

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

=item handle_sighup()

Handle a HUP signal. Nothing is done by default.

=item get_pid

=item save_pid

=item remove_pid

=item meta()

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

=back

=head1 DEPENDENCIES

=for author to fill in:
    A list of all the other modules that this module relies upon,
    including any restrictions on versions, and an indication whether
    the module is part of the standard Perl distribution, part of the
    module's distribution, or must be installed separately. ]

Obviously L<Moose>, also L<Carp>, L<Proc::Daemon>, L<File::Flock>, L<File::Slurp>

=head1 INCOMPATIBILITIES

=for author to fill in:
    A list of any modules that this module cannot be used in conjunction
    with. This may be due to name conflicts in the interface, or
    competition for system or program resources, or due to internal
    limitations of Perl (for example, many modules that use source code
    filters are mutually incompatible).

None reported.


=head1 BUGS AND LIMITATIONS

=for author to fill in:
    A list of known problems with the module, together with some
    indication Whether they are likely to be fixed in an upcoming
    release. Also a list of restrictions on the features the module
    does provide: data types that cannot be handled, performance issues
    and the circumstances in which they may arise, practical
    limitations on the size of data sets, special cases that are not
    (yet) handled, etc.

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 SEE ALSO

L<Proc::Daemon>, L<Daemon::Generic>, L<MooseX::Getopt>

=head1 AUTHOR

Chris Prather  C<< <perigrin@cpan.org> >>


=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.
Commit	Line	Data
a4952679	1	package MooseX::Daemonize;
a392fa53	2	use strict; # because Kwalitee is pedantic
a4952679	3	use Moose::Role;
	4
	5	our $VERSION = 0.01;
	6	use Carp;
	7	use Proc::Daemon;
a392fa53	8
a4952679	9	use File::Flock;
	10	use File::Slurp;
	11
	12	with qw(MooseX::Getopt);
	13
	14	has progname => (
a392fa53	15	isa => 'Str',
	16	is => 'ro',
	17	lazy => 1,
	18	required => 1,
	19	default => sub {
	20	( my $name = lc $_[0]->meta->name ) =~ s/::/_/g;
	21	return $name;
	22	},
a4952679	23	);
	24
	25	has pidbase => (
2361a590	26	isa => 'Str',
	27	is => 'ro',
	28
	29	# required => 1,
	30	lazy => 1,
	31	default => sub { return '/var/run' },
a4952679	32	);
	33
	34	has pidfile => (
	35	isa => 'Str',
	36	is => 'ro',
	37	lazy => 1,
	38	required => 1,
3543c999	39	default => sub {
	40	die 'Cannot write to ' . $_[0]->pidbase unless -w $_[0]->pidbase;
	41	$_[0]->pidbase . '/' . $_[0]->progname . '.pid';
	42	},
a4952679	43	);
	44
	45	has foreground => (
	46	metaclass => 'Getopt',
	47	cmd_aliases => ['f'],
	48	isa => 'Bool',
	49	is => 'ro',
	50	default => sub { 0 },
	51	);
	52
	53	sub check {
	54	my ($self) = @_;
3543c999	55	if ( my $pid = $self->get_pid ) {
a4952679	56	my $prog = $self->progname;
3543c999	57	if ( CORE::kill 0 => $pid ) {
a392fa53	58	croak "$prog already running ($pid).";
a4952679	59	}
ee08a7fe	60	carp "$prog not running but found pid ($pid)."
ee08a7fe	61	. "Perhaps the pid file (@{ [$self->pidfile] }) is stale?";
a4952679	62	return 1;
	63	}
	64	return 0;
	65	}
	66
a392fa53	67	sub daemonize {
	68	my ($self) = @_;
	69	Proc::Daemon::Init;
	70	}
	71
a4952679	72	sub start {
	73	my ($self) = @_;
	74	return if $self->check;
	75
	76	$self->daemonize unless $self->foreground;
	77
3543c999	78	# Avoid 'stdin reopened for output' warning with newer perls
	79	open( NULL, '/dev/null' );
	80	<NULL> if (0);
	81
	82	$self->save_pid;
	83	$self->setup_signals;
	84	return $$;
	85	}
	86
	87	sub save_pid {
	88	my ($self) = @_;
a4952679	89	my $pidfile = $self->pidfile;
	90	lock( $pidfile, undef, 'nonblocking' )
	91	or croak "Could not lock PID file $pidfile: $!";
	92	write_file( $pidfile, "$$\n" );
a392fa53	93	unlock($pidfile);
a4952679	94	return;
	95	}
	96
3543c999	97	sub remove_pid {
a4952679	98	my ($self) = @_;
a4952679	99	my $pidfile = $self->pidfile;
a4952679	100	lock( $pidfile, undef, 'nonblocking' )
a4952679	101	or croak "Could not lock PID file $pidfile: $!";
a4952679	102	unlink($pidfile);
a392fa53	103	unlock($pidfile);
a4952679	104	return;
	105	}
	106
3543c999	107	sub get_pid {
	108	my ($self) = @_;
	109	my $pidfile = $self->pidfile;
	110	return unless -e $pidfile;
	111	chomp( my $pid = read_file($pidfile) );
	112	return $pid;
	113	}
	114
	115	sub stop {
	116	my ( $self, %args ) = @_;
	117	my $pid = $self->get_pid;
	118	$self->kill($pid) unless $self->foreground();
	119	$self->remove_pid;
	120	return 1 if $args{no_exit};
	121	exit;
	122	}
	123
a4952679	124	sub restart {
a4952679	125	my ($self) = @_;
3543c999	126	$self->stop( noexit => 1 );
a4952679	127	$self->start();
	128	}
	129
a4952679	130	sub setup_signals {
3543c999	131	my ($self) = @_;
	132	$SIG{INT} = sub { $self->handle_sigint; };
	133	$SIG{HUP} = sub { $self->handle_sighup };
a4952679	134	}
a4952679	135
2361a590	136	sub handle_sigint { $_[0]->stop; }
2361a590	137	sub handle_sighup { $_[0]->restart; }
a4952679	138
	139	sub kill {
	140	my ( $self, $pid ) = @_;
2361a590	141	return unless $pid;
3543c999	142	unless ( CORE::kill 0 => $pid ) {
	143
	144	# warn "$pid already appears dead.";
	145	return;
	146	}
	147
	148	if ( $pid eq $$ ) {
	149
	150	# warn "$pid is us! Can't commit suicied.";
a4952679	151	return;
	152	}
	153
3543c999	154	CORE::kill( 2, $pid ); # Try SIGINT
2361a590	155	sleep(2) if CORE::kill( 0, $pid );
a4952679	156
3543c999	157	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	158	CORE::kill( 15, $pid ); # try SIGTERM
2361a590	159	sleep(2) if CORE::kill( 0, $pid );
a4952679	160	}
a4952679	161
3543c999	162	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	163	CORE::kill( 9, $pid ); # finally try SIGKILL
2361a590	164	sleep(2) if CORE::kill( 0, $pid );
a4952679	165	}
a4952679	166
3543c999	167	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	168	carp "$pid doesn't seem to want to die."; # AHH EVIL DEAD!
a4952679	169	}
	170
	171	return;
	172	}
	173
	174	1;
	175	__END__
	176
a4952679	177	=head1 NAME
	178
	179	MooseX::Daemonize - provides a Role that daemonizes your Moose based application.
	180
	181
	182	=head1 VERSION
	183
	184	This document describes MooseX::Daemonize version 0.0.1
	185
	186
	187	=head1 SYNOPSIS
	188
	189	package FileMaker;
	190	use Moose;
	191	with qw(MooseX::Daemonize);
	192
	193	sub create_file {
	194	my ( $self, $file ) = @_;
	195	open( FILE, ">$file" ) \|\| die;
	196	close(FILE);
	197	}
	198
	199	no Moose;
	200
	201	# then in the main package ...
	202
	203	my $daemon = FileMaker->new();
	204	$daemon->start();
	205	$daemon->create_file($file);
	206	$daemon->stop();
	207
	208	=head1 DESCRIPTION
	209
	210	Often you want to write a persistant daemon that has a pid file, and responds appropriately to Signals.
	211	This module helps provide the basic infrastructure to do that.
	212
	213	=head1 ATTRIBUTES
	214
	215	=over
	216
	217	=item progname Str
	218
	219	The name of our daemon, defaults to $0
	220
	221	=item pidbase Str
	222
	223	The base for our bid, defaults to /var/run/$progname
	224
	225	=item pidfile Str
	226
	227	The file we store our PID in, defaults to /var/run/$progname/
	228
	229	=item foreground Bool
	230
	231	If true, the process won't background. Useful for debugging. This option can be set via Getopt's -f.
	232
	233	=back
	234
	235	=head1 METHODS
	236
	237	=over
	238
	239	=item check()
	240
241	Check to see if an instance is already running.
242
243	=item start()
244
245	Setup a pidfile, fork, then setup the signal handlers.
246
247	=item stop()
248
249	Stop the process matching the pidfile, and unlinks the pidfile.
250
251	=item restart()
252
253	Litterally
254
255	$self->stop();
256	$self->start();
257
258	=item daemonize()
259
260	Calls C<Proc::Daemon::Init> to daemonize this process.
261
262	=item kill($pid)
263
264	Kills the process for $pid. This will try SIGINT, and SIGTERM before falling back to SIGKILL and finally giving up.
265
266	=item setup_signals()
267
268	Setup the signal handlers, by default it only sets up handlers for SIGINT and SIGHUP
269
270	=item handle_sigint()
271
272	Handle a INT signal, by default calls C<$self->stop()>;
273
274	=item handle_sighup()
275
276	Handle a HUP signal. Nothing is done by default.
277
3543c999	278	=item get_pid
	279
	280	=item save_pid
	281
	282	=item remove_pid
	283
a4952679	284	=item meta()
	285
	286	the C<meta()> method from L<Class::MOP::Class>
	287
	288	=back
	289
	290	=head1 DEPENDENCIES
	291
	292	=for author to fill in:
	293	A list of all the other modules that this module relies upon,
	294	including any restrictions on versions, and an indication whether
	295	the module is part of the standard Perl distribution, part of the
	296	module's distribution, or must be installed separately. ]
	297
	298	Obviously L<Moose>, also L<Carp>, L<Proc::Daemon>, L<File::Flock>, L<File::Slurp>
	299
	300	=head1 INCOMPATIBILITIES
	301
	302	=for author to fill in:
	303	A list of any modules that this module cannot be used in conjunction
	304	with. This may be due to name conflicts in the interface, or
	305	competition for system or program resources, or due to internal
	306	limitations of Perl (for example, many modules that use source code
	307	filters are mutually incompatible).
	308
	309	None reported.
	310
	311
	312	=head1 BUGS AND LIMITATIONS
	313
	314	=for author to fill in:
	315	A list of known problems with the module, together with some
	316	indication Whether they are likely to be fixed in an upcoming
	317	release. Also a list of restrictions on the features the module
	318	does provide: data types that cannot be handled, performance issues
	319	and the circumstances in which they may arise, practical
	320	limitations on the size of data sets, special cases that are not
	321	(yet) handled, etc.
	322
	323	No bugs have been reported.
	324
	325	Please report any bugs or feature requests to
	326	C<bug-acme-dahut-call@rt.cpan.org>, or through the web interface at
	327	L<http://rt.cpan.org>.
	328
	329	=head1 SEE ALSO
	330
	331	L<Proc::Daemon>, L<Daemon::Generic>, L<MooseX::Getopt>
	332
	333	=head1 AUTHOR
	334
	335	Chris Prather C<< <perigrin@cpan.org> >>
	336
	337
	338	=head1 LICENCE AND COPYRIGHT
	339
	340	Copyright (c) 2007, Chris Prather C<< <perigrin@cpan.org> >>. All rights reserved.
	341
	342	This module is free software; you can redistribute it and/or
	343	modify it under the same terms as Perl itself. See L<perlartistic>.
	344
	345
	346	=head1 DISCLAIMER OF WARRANTY
	347
348	BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
349	FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
350	OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
351	PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
352	EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
353	WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
354	ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
355	YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
356	NECESSARY SERVICING, REPAIR, OR CORRECTION.
357
358	IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
359	WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
360	REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
361	LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
362	OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
363	THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
364	RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
365	FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
366	SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
367	SUCH DAMAGES.