NAME
MooseX::Workers - Simple sub-process management for asynchronous tasks
SYNOPSIS
package Manager;
use Moose;
with qw(MooseX::Workers);
sub run {
$_[0]->spawn( sub { sleep 3; print "Hello World\n" } );
warn "Running now ... ";
POE::Kernel->run();
}
# Implement our Interface
sub worker_manager_start { warn 'started worker manager' }
sub worker_manager_stop { warn 'stopped worker manager' }
sub max_workers_reached { warn 'maximum worker count reached' }
sub worker_stdout { shift; warn join ' ', @_; }
sub worker_stderr { shift; warn join ' ', @_; }
sub worker_error { shift; warn join ' ', @_; }
sub worker_done { shift; warn join ' ', @_; }
sub worker_started { shift; warn join ' ', @_; }
sub sig_child { shift; warn join ' ', @_; }
no Moose;
Manager->new->run();DESCRIPTION
MooseX::Workers is a Role that provides easy delegation of long-running tasks into a managed child process. Process managment is taken care of via POE and it's POE::Wheel::Run module.
METHODS
- spawn ($command)
- fork ($command)
- run_command ($command)
-
These three methods are the whole point of this module. They pass $command through to the MooseX::Worker::Engine which will take care of running $command for you.
spawn() and fork() both envoke POE::Kernel call(), which is synchronous.
run_command() envokes POE::Kernel yield(), which is asynchronous.
If max_workers() has been reached, run_command() warns and does nothing. It is up to you to re-submit $command. See enqueue() if you want us to run $command as soon as another worker is free.
- enqueue($command)
-
Just like run_command(), only that if max_workers() has been set and that number of workers has been reached, then we add $command to a FIFO command queue. As soon as any running worker exits, the first $command in queue (if any) will be run.
- check_worker_threshold
-
This will check to see how many workers you have compared to the max_workers limit. It returns true if the $num_workers is >= $max_workers;
- max_workers($count)
-
An accessor for the maxium number of workers. This is delegated to the MooseX::Workers::Engine object.
- has_workers
-
Check to see if we have *any* workers currently. This is delegated to the MooseX::Workers::Engine object.
- num_workers
-
Return the current number of workers. This is delegated to the MooseX::Workers::Engine object.
- meta
-
The Metaclass for MooseX::Workers::Engine see Moose's documentation.
INTERFACE
MooseX::Worker::Engine supports the following callbacks:
- worker_manager_start
-
Called when the managing session is started
- worker_manager_stop
-
Called when the managing session stops
- max_workers_reached
-
Called when we reach the maximum number of workers
- worker_stdout
-
Called when a child prints to STDOUT
- worker_stderr
-
Called when a child prints to STDERR
- worker_error
-
Called when there is an error condition detected with the child.
- worker_done
-
Called when a worker completes $command
- worker_started
-
Called when a worker starts $command
- sig_child
-
Called when the mangaging session recieves a SIG CHDL event
See MooseX::Workers::Engine for more details. Also see MooseX::Workers::Job if you'd like to give your tasks names, or set timeouts on them.
CONFIGURATION AND ENVIRONMENT
MooseX::Workers requires no configuration files or environment variables.
DEPENDENCIES
Moose, POE, POE::Wheel::Run
INCOMPATIBILITIES
None reported.
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests to bug-moosex-workers@rt.cpan.org, or through the web interface at http://rt.cpan.org.
AUTHORS
Chris Prather <perigrin@cpan.org>
Tom Lanyon <dec@cpan.org>
Jay Hannah <jay@jays.net>
Justin Hunter <justin.d.hunter@gmail.com>
LICENCE AND COPYRIGHT
Copyright (c) 2007-2010, Chris Prather <perigrin@cpan.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.