package Admin_server::Parser;
use MooseX::FollowPBP;    # Simon Cozens Perl Best Practices.
use Moose;                # Sugar!!
use Module::Pluggable::Object;    # To enable application plugins.

use aliased 'Admin_server::Interface::ParserInterface';

#----------------------------------------------------------
#  Define attributes.
#----------------------------------------------------------
has 'plugins' => ( is => 'ro', lazy_build => 1, isa => 'HashRef' );
<readmore>

#----------------------------------------------------------
#  Define methods.
#----------------------------------------------------------
sub _build_plugins { 

#===  FUNCTION  ====================================
#         NAME:  _build_plugins
#      PURPOSE:  To build up the applications hash.
#   PARAMETERS:  None.
#      RETURNS:  Nothing.
#  DESCRIPTION:  Populates the applications hash with the list of 
#               available application parser plugins.
#       THROWS:  no exceptions
#     COMMENTS:  none
#===============================================
    my ($self) = @_;
    
    my $base = __PACKAGE__ . '::Plugin';# Location of parser plugins.
        
    my %parser_plugins;       # Stores the instantiated plugins.
        
    # Scan plugins at $base.
    my $mpo = Module::Pluggable::Object->new( search_path => [$base] );
    my @available_plugins = $mpo->plugins();
        
    print 'Found plugins ...', "@available_plugins", "\n";
          
    # Load the available plugins.
    foreach my $plugin (@available_plugins) {
        print "Loading plugin $plugin", "\n";
        Class::MOP::load_class($plugin);

        print "finished loading $plugin" . "\n"
          if ( Class::MOP::is_class_loaded($plugin) );

        # Ensure that each class confirms to the plugin API.
        confess("Plugin $plugin in ${base}"
              . ' namespace doesn\'t implement ParserInterface.' )
          unless ( $plugin->does(ParserInterface) );

        # Record and instantiate the valid plugin objects in a hash.
        ( my $plugin_name = $plugin ) =~ s/\Q${base}::\E//;
        $parser_plugins{$plugin_name} = $plugin->new();
    }

    print STDOUT sort keys %parser_plugins, "\n";

    return \%parser_plugins;
}    # ----------  end of subroutine _build_applications  ----------
</readmore>

##</code><code>##

$prove -lv t/Parser.t
t/Parser.t .. 
1..4
ok 1 - use Admin_server::Parser;
ok 2 - Admin_server::Parser can be instantiated.
ok 3 - Instantiated object is of type Admin_server::Parser
Found plugins ...Admin_server::Parser::Plugin::FeedHandler
Loading plugin Admin_server::Parser::Plugin::FeedHandler
Can't locate object method "does" via package "Admin_server::Parser::Plugin::FeedHandler" (perhaps you forgot to load "Admin_server::Parser::Plugin::FeedHandler"?) at /Volumes/UserData/Users/tintin/Programs/Perl/Work_area/Admin_server/lib/Admin_server/Parser.pm line 68.
# Looks like you planned 4 tests but ran 3.
# Looks like your test exited with 255 just after 3.
Dubious, test returned 255 (wstat 65280, 0xff00)
Failed 1/4 subtests 

Test Summary Report
-------------------
t/Parser.t (Wstat: 65280 Tests: 3 Failed: 0)
  Non-zero exit status: 255
  Parse errors: Bad plan.  You planned 4 tests but ran 3.
Files=1, Tests=3,  1 wallclock secs ( 0.03 usr  0.01 sys +  0.24 cusr  0.02 csys =  0.30 CPU)
Result: FAIL

##</code><code>##

############################################################
###########       PRAGMATA                          ########
############################################################
use strict;
use warnings;

use Test::More tests => 4;    # last test to print

############################################################
###########        VARIABLES USED                   ########
############################################################

############################################################
###########         TESTING BEGINS                  ########
############################################################
#----------------------------------------------------------
# Ensure that Admin_server::Parser can be use'd.
#----------------------------------------------------------
BEGIN {
    use_ok('Admin_server::Parser');
}

#----------------------------------------------------------
# Check if the plugin can be instantiated.
#----------------------------------------------------------
ok(
    my $parser = Admin_server::Parser->new(),
    'Admin_server::Parser can be instantiated.'
);

#----------------------------------------------------------
# Conform that the new object is of the correct type.
#----------------------------------------------------------
is( ref($parser), 'Admin_server::Parser',
    'Instantiated object is of type Admin_server::Parser' );

#----------------------------------------------------------
# Check whether plugins are correctly loaded.
#----------------------------------------------------------
ok( $parser->get_plugins(), 'Plugin hash can be accessed.' );

#ok( exists ${ $parser->get_plugins() }->{'FeedHandler'},
#    'Feed handler plugin found.' );

done_testing();

##</code><code>##

$ls -1R
bin
config
lib
logs
t

./bin:
Master_server.pl
Master_server.pl.bkp

./config:
admin_server.conf

./lib:
Admin_server

./lib/Admin_server:
Interface
Parser
Parser.pm

./lib/Admin_server/Interface:
ParserInterface.pm

./lib/Admin_server/Parser:
Plugin

./lib/Admin_server/Parser/Plugin:
FeedHandler.pm

./logs:
Application
admin_server.log

./logs/Application:

./t:
01app.t
Interface
Parser.t
Plugin

./t/Interface:
ParserInterface.t

./t/Plugin:
FeedHandler.t