NAME¶
MooseX::Daemonize - Role for daemonizing your Moose based application
VERSION¶
version 0.19
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 persistent 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/"
- basedir Path::Class::Dir | Str
- The directory we chdir to; defaults to "/".
- 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 acquiring 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 overridable 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-MooseX-Daemonize@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
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POSSIBILITY OF SUCH DAMAGES.