NAME
    Parallel::Workers - run worker tasks in parallel. Worker task is a
    plugin that you can implement. The availables are Eval for CODE, SSH and
    XMLRPC.

VERSION
    This document describes Parallel::Workers version *$VERSION*

SYNOPSIS
        use Parallel::Workers;
    
        #Workers that use Eval action with a trantransaction controller
        #                 ^^^^
    
        my $worker=Parallel::Workers->new(maxworkers=>4,timeout=>10, backend=>"Eval");

        my $id=$worker->create(hosts => \@named, command=>"`date`", 
                               transaction=>{error=>TRANSACTION_TERM, type=>'SCALAR',regex => qr/.+/m});
        my $info=$worker->info();
    
        #Workers that use SSH action with a trantransaction controller
        #                 ^^^
        $worker=Parallel::Workers->new(
                                        maxworkers=>16,timeout=>10, 
                                        backend=>"SSH", constructor =>{user=>'demo',pass=>'demo'}
                                      );

        $id=$worker->create(hosts => \@hosts, command=>"cat /proc/cmdline",
                                          transaction=>{error=>TRANSACTION_TERM, type=>'SCALAR',regex => qr/.+/m}); 

DESCRIPTION
    This *Parallel::Workers* allow you to run multiples tasks in parallel
    with or without error check (see *Parallel::Workers::Transaction*).

    You can specify maxworkers value that limit the max parallel task
    (threads pool). You can specify the backend that run the task, currently
    only Eval, SSH and XMLRPC are implemented, but you can make yours for
    your needs.

    Workers run simples tasks that return value. You can specify different
    way to check the return value and on error you decide to stop or
    continue the main workers (see *Parallel::Workers::Transaction*).

            # workers TERM if return value is not in this regex /.+/m
            $id=$worker->create(...,
                                transaction=>{error=>TRANSACTION_TERM, type=>'SCALAR',regex => qr/.+/m }; 
        
            # workers TERM if return value is not 127
            $id=$worker->create(...,
                                transaction=>{error=>TRANSACTION_TERM, type=>'SCALAR',check => 127}; 

            # workers TERM if return value is not an HASH
            $id=$worker->create(...,
                                transaction=>{error=>TRANSACTION_TERM, type=>'ARRAY'}; 

            # workers CONTINUE on error
            $id=$worker->create(...,
                                transaction=>{error=>TRANSACTION_CONT, ...}; 

METHODS
  new([%h])
    Constructor. %h is a hash of attributes :

        maxworkers:16 , the max parallel tasks (threads)
        timeout:10, the time in second before to kill thread (only when stop workers)
        backend:undef, the task 
        constructor:undef, the task constructor
    
  info()
      return all workers results
  
  create(hosts => @hosts, spawn=>0, command=>$cmd, params=>%h|@a|$r, transaction=>%h)
  stop
  clear
  join
DIAGNOSTICS
    "Error message here, perhaps with %s placeholders"
        [Description of error here]

    "Another error message here"
        [Description of error here]

        [Et cetera, et cetera]

CONFIGURATION AND ENVIRONMENT
    Parallel::Workers requires no configuration files or environment
    variables.

DEPENDENCIES
    None.

INCOMPATIBILITIES
    None reported.

BUGS AND LIMITATIONS
    No bugs have been reported.

    Please report any bugs or feature requests to
    "bug-parallel-jobs@rt.cpan.org", or through the web interface at
    <http://rt.cpan.org>.

AUTHOR
    Olivier Evalet "<evaleto@gelux.ch>"

LICENCE AND COPYRIGHT
    Copyright (c) 2006, Olivier Evalet "<evaleto@gelux.ch>". All 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.

