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

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

our $VERSION = 0.02;
use Carp;
use Proc::Daemon;

use File::Pid;
use Moose::Util::TypeConstraints;

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 basedir => (
    isa      => 'Str',
    is       => 'ro',
    required => 1,
    lazy     => 1,
    default  => sub { return '/' },
);

has pidbase => (
    isa      => 'Str',
    is       => 'ro',
    lazy     => 1,
    required => 1,
    default  => sub { return '/var/run' },
);

subtype 'Pidfile' => as 'Object' => where { $_->isa('File::Pid') };

coerce 'Pidfile' => from 'Str' => via { File::Pid->new( { file => $_, } ); };

has pidfile => (
    isa       => 'Pidfile',
    is        => 'rw',
    lazy      => 1,
    required  => 1,
    coerce    => 1,
    predicate => 'has_pidfile',
    default   => sub {
        die 'Cannot write to ' . $_[0]->pidbase unless -w $_[0]->pidbase;
        my $file = $_[0]->pidbase . '/' . $_[0]->progname . '.pid';
        File::Pid->new( { file => $file } );
    },
    handles => {
        check      => 'running',
        save_pid   => 'write',
        remove_pid => 'remove',
        get_pid    => 'pid',
        _pidfile   => 'file',
    },
);

has foreground => (
    metaclass   => 'MooseX::Getopt::Meta::Attribute',
    cmd_aliases => 'f',
    isa         => 'Bool',
    is          => 'ro',
    default     => sub { 0 },
);

has is_daemon => (
    isa     => 'Bool',
    is      => 'rw',
    default => sub { 0 },
);

sub daemonize {
    my ($self) = @_;
    return if Proc::Daemon::Fork;
    Proc::Daemon::Init;
    $self->is_daemon(1);
}

sub start {
    my ($self) = @_;
    confess "instance already running" if $self->check;
    $self->daemonize unless $self->foreground;

    return unless $self->is_daemon;

    $self->pidfile->pid($$);

    # Avoid 'stdin reopened for output' warning with newer perls
    ## no critic
    open( NULL, '/dev/null' );
    <NULL> if (0);
    ## use critic

    # Change to basedir
    chdir $self->basedir;

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

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( no_exit => 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 {
    confess "_kill isn't public" unless caller eq __PACKAGE__;
    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(3) 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 $self->meta->name =~ s/::/_/;

=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. By default calls C<$self->restart()>

=item get_pid

Lookup the pid from our pidfile.

=item save_pid

Save the current pid in our pidfile

=item remove_pid

Delete our pidfile

=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::Pid>

=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 THANKS

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

=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;
a4952679	4
cbff8e52	5	our $VERSION = 0.02;
a4952679	6	use Carp;
a4952679	7	use Proc::Daemon;
a392fa53	8
fa2b72a4	9	use File::Pid;
fa2b72a4	10	use Moose::Util::TypeConstraints;
a4952679	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	);
a4952679	24
24a6a660	25	has basedir => (
cbff8e52	26	isa => 'Str',
	27	is => 'ro',
	28	required => 1,
	29	lazy => 1,
	30	default => sub { return '/' },
24a6a660	31	);
24a6a660	32
a4952679	33	has pidbase => (
cbff8e52	34	isa => 'Str',
	35	is => 'ro',
	36	lazy => 1,
	37	required => 1,
	38	default => sub { return '/var/run' },
a4952679	39	);
a4952679	40
fa2b72a4	41	subtype 'Pidfile' => as 'Object' => where { $_->isa('File::Pid') };
cbff8e52	42
cbff8e52	43	coerce 'Pidfile' => from 'Str' => via { File::Pid->new( { file => $_, } ); };
fa2b72a4	44
a4952679	45	has pidfile => (
cbff8e52	46	isa => 'Pidfile',
	47	is => 'rw',
	48	lazy => 1,
	49	required => 1,
	50	coerce => 1,
	51	predicate => 'has_pidfile',
	52	default => sub {
3543c999	53	die 'Cannot write to ' . $_[0]->pidbase unless -w $_[0]->pidbase;
fa2b72a4	54	my $file = $_[0]->pidbase . '/' . $_[0]->progname . '.pid';
	55	File::Pid->new( { file => $file } );
	56	},
	57	handles => {
	58	check => 'running',
	59	save_pid => 'write',
	60	remove_pid => 'remove',
	61	get_pid => 'pid',
cbff8e52	62	_pidfile => 'file',
3543c999	63	},
a4952679	64	);
	65
	66	has foreground => (
cbff8e52	67	metaclass => 'MooseX::Getopt::Meta::Attribute',
cbff8e52	68	cmd_aliases => 'f',
a4952679	69	isa => 'Bool',
	70	is => 'ro',
	71	default => sub { 0 },
	72	);
	73
cbff8e52	74	has is_daemon => (
	75	isa => 'Bool',
	76	is => 'rw',
	77	default => sub { 0 },
	78	);
	79
a392fa53	80	sub daemonize {
a392fa53	81	my ($self) = @_;
cbff8e52	82	return if Proc::Daemon::Fork;
a392fa53	83	Proc::Daemon::Init;
cbff8e52	84	$self->is_daemon(1);
a392fa53	85	}
a392fa53	86
a4952679	87	sub start {
a4952679	88	my ($self) = @_;
cbff8e52	89	confess "instance already running" if $self->check;
a4952679	90	$self->daemonize unless $self->foreground;
a4952679	91
cbff8e52	92	return unless $self->is_daemon;
	93
	94	$self->pidfile->pid($$);
	95
3543c999	96	# Avoid 'stdin reopened for output' warning with newer perls
0585edbb	97	## no critic
3543c999	98	open( NULL, '/dev/null' );
3543c999	99	<NULL> if (0);
0585edbb	100	## use critic
fa2b72a4	101
24a6a660	102	# Change to basedir
24a6a660	103	chdir $self->basedir;
fa2b72a4	104
3543c999	105	$self->save_pid;
	106	$self->setup_signals;
	107	return $$;
	108	}
	109
3543c999	110	sub stop {
	111	my ( $self, %args ) = @_;
	112	my $pid = $self->get_pid;
cecbee2d	113	$self->_kill($pid) unless $self->foreground();
3543c999	114	$self->remove_pid;
	115	return 1 if $args{no_exit};
	116	exit;
	117	}
	118
a4952679	119	sub restart {
a4952679	120	my ($self) = @_;
7ada91b8	121	$self->stop( no_exit => 1 );
a4952679	122	$self->start();
	123	}
	124
a4952679	125	sub setup_signals {
3543c999	126	my ($self) = @_;
	127	$SIG{INT} = sub { $self->handle_sigint; };
	128	$SIG{HUP} = sub { $self->handle_sighup };
a4952679	129	}
a4952679	130
2361a590	131	sub handle_sigint { $_[0]->stop; }
2361a590	132	sub handle_sighup { $_[0]->restart; }
a4952679	133
cecbee2d	134	sub _kill {
cecbee2d	135	confess "_kill isn't public" unless caller eq __PACKAGE__;
a4952679	136	my ( $self, $pid ) = @_;
2361a590	137	return unless $pid;
3543c999	138	unless ( CORE::kill 0 => $pid ) {
	139
	140	# warn "$pid already appears dead.";
	141	return;
	142	}
	143
	144	if ( $pid eq $$ ) {
	145
	146	# warn "$pid is us! Can't commit suicied.";
a4952679	147	return;
	148	}
	149
3543c999	150	CORE::kill( 2, $pid ); # Try SIGINT
2361a590	151	sleep(2) if CORE::kill( 0, $pid );
a4952679	152
3543c999	153	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	154	CORE::kill( 15, $pid ); # try SIGTERM
2361a590	155	sleep(2) if CORE::kill( 0, $pid );
a4952679	156	}
a4952679	157
3543c999	158	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	159	CORE::kill( 9, $pid ); # finally try SIGKILL
7ada91b8	160	sleep(3) if CORE::kill( 0, $pid );
a4952679	161	}
a4952679	162
3543c999	163	unless ( CORE::kill 0 => $pid or $!{EPERM} ) { # IF it is still running
3543c999	164	carp "$pid doesn't seem to want to die."; # AHH EVIL DEAD!
a4952679	165	}
	166
	167	return;
	168	}
	169
	170	1;
	171	__END__
	172
a4952679	173	=head1 NAME
	174
	175	MooseX::Daemonize - provides a Role that daemonizes your Moose based application.
	176
	177
	178	=head1 VERSION
	179
	180	This document describes MooseX::Daemonize version 0.0.1
	181
	182
	183	=head1 SYNOPSIS
	184
	185	package FileMaker;
	186	use Moose;
	187	with qw(MooseX::Daemonize);
	188
	189	sub create_file {
	190	my ( $self, $file ) = @_;
	191	open( FILE, ">$file" ) \|\| die;
	192	close(FILE);
	193	}
	194
	195	no Moose;
	196
	197	# then in the main package ...
	198
	199	my $daemon = FileMaker->new();
	200	$daemon->start();
	201	$daemon->create_file($file);
	202	$daemon->stop();
	203
	204	=head1 DESCRIPTION
	205
	206	Often you want to write a persistant daemon that has a pid file, and responds appropriately to Signals.
	207	This module helps provide the basic infrastructure to do that.
	208
	209	=head1 ATTRIBUTES
	210
	211	=over
	212
	213	=item progname Str
	214
cbff8e52	215	The name of our daemon, defaults to $self->meta->name =~ s/::/_/;
a4952679	216
	217	=item pidbase Str
	218
	219	The base for our bid, defaults to /var/run/$progname
	220
	221	=item pidfile Str
	222
	223	The file we store our PID in, defaults to /var/run/$progname/
	224
	225	=item foreground Bool
	226
	227	If true, the process won't background. Useful for debugging. This option can be set via Getopt's -f.
	228
	229	=back
	230
	231	=head1 METHODS
	232
	233	=over
	234
	235	=item check()
	236
	237	Check to see if an instance is already running.
	238
	239	=item start()
	240
	241	Setup a pidfile, fork, then setup the signal handlers.
	242
	243	=item stop()
	244
	245	Stop the process matching the pidfile, and unlinks the pidfile.
	246
	247	=item restart()
	248
	249	Litterally
	250
	251	$self->stop();
	252	$self->start();
	253
	254	=item daemonize()
	255
	256	Calls C<Proc::Daemon::Init> to daemonize this process.
	257
	258	=item kill($pid)
	259
	260	Kills the process for $pid. This will try SIGINT, and SIGTERM before falling back to SIGKILL and finally giving up.
	261
	262	=item setup_signals()
	263
	264	Setup the signal handlers, by default it only sets up handlers for SIGINT and SIGHUP
	265
	266	=item handle_sigint()
	267
cecbee2d	268	Handle a INT signal, by default calls C<$self->stop()>
a4952679	269
	270	=item handle_sighup()
	271
cecbee2d	272	Handle a HUP signal. By default calls C<$self->restart()>
a4952679	273
3543c999	274	=item get_pid
3543c999	275
cecbee2d	276	Lookup the pid from our pidfile.
cecbee2d	277
3543c999	278	=item save_pid
3543c999	279
cecbee2d	280	Save the current pid in our pidfile
cecbee2d	281
3543c999	282	=item remove_pid
3543c999	283
cecbee2d	284	Delete our pidfile
cecbee2d	285
a4952679	286	=item meta()
a4952679	287
cecbee2d	288	The C<meta()> method from L<Class::MOP::Class>
a4952679	289
	290	=back
	291
	292	=head1 DEPENDENCIES
	293
	294	=for author to fill in:
	295	A list of all the other modules that this module relies upon,
	296	including any restrictions on versions, and an indication whether
	297	the module is part of the standard Perl distribution, part of the
	298	module's distribution, or must be installed separately. ]
	299
fa2b72a4	300	Obviously L<Moose>, also L<Carp>, L<Proc::Daemon>, L<File::Pid>
a4952679	301
	302	=head1 INCOMPATIBILITIES
	303
	304	=for author to fill in:
	305	A list of any modules that this module cannot be used in conjunction
	306	with. This may be due to name conflicts in the interface, or
	307	competition for system or program resources, or due to internal
	308	limitations of Perl (for example, many modules that use source code
	309	filters are mutually incompatible).
	310
	311	None reported.
	312
	313
	314	=head1 BUGS AND LIMITATIONS
	315
	316	=for author to fill in:
	317	A list of known problems with the module, together with some
	318	indication Whether they are likely to be fixed in an upcoming
	319	release. Also a list of restrictions on the features the module
	320	does provide: data types that cannot be handled, performance issues
	321	and the circumstances in which they may arise, practical
	322	limitations on the size of data sets, special cases that are not
	323	(yet) handled, etc.
	324
	325	No bugs have been reported.
	326
	327	Please report any bugs or feature requests to
	328	C<bug-acme-dahut-call@rt.cpan.org>, or through the web interface at
	329	L<http://rt.cpan.org>.
	330
	331	=head1 SEE ALSO
	332
	333	L<Proc::Daemon>, L<Daemon::Generic>, L<MooseX::Getopt>
	334
	335	=head1 AUTHOR
	336
	337	Chris Prather C<< <perigrin@cpan.org> >>
	338
7ada91b8	339	=head1 THANKS
	340
	341	Mike Boyko, Matt S. Trout, Stevan Little, Brandon Black, and the #moose denzians
a4952679	342
	343	=head1 LICENCE AND COPYRIGHT
	344
	345	Copyright (c) 2007, Chris Prather C<< <perigrin@cpan.org> >>. All rights reserved.
	346
	347	This module is free software; you can redistribute it and/or
	348	modify it under the same terms as Perl itself. See L<perlartistic>.
	349
	350
	351	=head1 DISCLAIMER OF WARRANTY
	352
	353	BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
	354	FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
	355	OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
	356	PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
	357	EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	358	WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
	359	ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
	360	YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
	361	NECESSARY SERVICING, REPAIR, OR CORRECTION.
	362
	363	IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
	364	WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
	365	REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
	366	LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
	367	OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
	368	THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
	369	RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
	370	FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
	371	SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
	372	SUCH DAMAGES.