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__END__

=pod

=head1 NAME

Poet::Manual::Subclassing - Customizing Poet with subclasses

=head1 DESCRIPTION

You can subclass the following Poet classes for your application:

    Poet::Cache
    Poet::Conf
    Poet::Log
    Poet::Mason
    Poet::Import
    Poet::Plack::Request
    Poet::Plack::Response

and arrange things so that Poet always uses your subclass instead of its
default class.

Place Poet subclasses under C<lib/MyApp/Class.pm> in your environment, where
C<MyApp> is your app name and C<Class> is the class you are subclassing minus
the C<Poet> prefix. A few of these subclasses are generated for you by C<poet
new>.

For example, to subclass C<Poet::Cache>:

    package MyApp::Cache;
    use Poet::Moose;
    extends 'Poet::Cache';

    # put your modifications here

    1;

(Note: L<Poet::Moose|Poet::Moose> is Moose plus a few Poet standards. You could
also use plain C<Moose> here.)

Poet will automatically detect, load and use any such subclasses. Internally it
uses the L<app_class|Poet::Environment/app_class> environment method whenever
it needs a classname, e.g.

    # Do something with MyApp::Cache or Poet::Cache
    $poet->app_class('Cache')->...

=head2 Subclassing Mason

As long as you have even a bare-bones C<Poet::Mason> subclass, e.g.

    package MyApp::Mason;
    use Poet::Moose;
    extends 'Poet::Mason';

    1;

then your Mason subclasses will be autodetected as well, e.g.

    package MyApp::Mason::Interp;
    use Moose;
    extends 'Mason::Interp';
    # put your modifications here
    1;

C<poet new> will create the bare-bones subclass for you; it is otherwise
harmless.

See L<Mason::Manual::Subclasses|Mason::Manual::Subclasses> for more
information.

=head1 EXAMPLES

=head2 Use INI instead of YAML for config files

    package MyApp::Conf;
    use Config::INI;
    use Moose;
    extends 'Poet::Conf';

    override 'read_conf_file' => sub {
        my ($self, $file) = @_;
        return Config::INI::Reader->read_file($file);
    };

=head2 Perform tasks before and after each Mason request

    package MyApp::Mason::Request;
    use Moose;
    extends 'Mason::Request';

    override 'run' => sub {
        my $self = shift;

        # Perform tasks before request
        my $result = super();
        # Perform tasks after request

        return $result;
    };

=head2 Add Perl code to the top of every compiled component

    package MyApp::Mason::Compilation;
    use Moose;
    extends 'Mason::Compilation';

    override 'output_class_header' => sub {
         return join("\n", super(), 'use Foo;', 'use Bar qw(baz);');
    };

=head2 Use Log::Dispatch instead of Log4perl for logging

    package MyApp::Log;
    use Log::Any::Adapter;
    use Log::Dispatch;
    use Moose;
    extends 'Poet::Log';

    override 'initialize_logging' => sub {
        my $log = Log::Dispatch->new( ... );
        Log::Any::Adapter->set('Dispatch', dispatcher => $log);
    };

=head2 Add your own $dbh quick var

    package MyApp::Import
    use DBI;
    use Poet::Moose;
    extends 'Poet::Import';
    
    method provide_dbh ($caller, $poet) {
        $dbh = DBI->connect(...);
    }

=head1 SEE ALSO

L<Poet|Poet>

=head1 AUTHOR

Jonathan Swartz <swartz@pobox.com>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2012 by Jonathan Swartz.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut