NAME

       MooseX::Configuration - Define attributes which come from configuration files

VERSION

       version 0.02

SYNOPSIS

         package MyApp::Config;

         use Moose;
         use MooseX::Configuration;

         has database_name => (
             is      => 'ro',
             isa     => 'Str',
             default => 'MyApp',
             section => 'database',
             key     => 'name',
             documentation =>
                 'The name of the database.',
         );

         has database_username => (
             is      => 'ro',
             isa     => Str,
             default => q{},
             section => 'database',
             key     => 'username',
             documentation =>
                 'The username to use when connecting to the database. By default, this is empty.',
         );

         my $config = MyApp::Config->new( config_file => '/path/to/config/myapp.ini' );
         $config->write_file( ... );

DESCRIPTION

       This module lets you define attributes which can come from a configuration file. It also
       adds a role to your class which allows you to write a configuration file.

       It is based on using a simple INI-style configuration file, which contains sections and
       keys:

         key1 = value
         key2 = 42

         [section]
         key3 = 2

ATTRIBUTE API

       Simply using this module in your class changes your class's attribute metaclass to add
       support for defining attributes as configuration items.

       There are two new parameters you can pass when defining an attribute, "section" and "key".
       These tell the module how to find the attribute's value in the configuration file. The
       "section" parameter is optional. If you don't set it, but do provide a key, then the
       section defaults to "_", which is the main section of the config file.

       If you pass a "section" you must also pass a "key".

       Defining an attribute as a configuration item has several effects. First, it changes the
       default value for the attribute. Before looking at a "default" or "builder" you define,
       the attribute will first look in the config file for a corresponding value. If one exists,
       it will use that, otherwise it will fall back to using a default you supply.

       If you do supply a default, it must be a string (or number), not a reference or undefined
       value.

       All configuration attributes are lazy. This is necessary because the configuration file
       needs to be loaded and parsed before looking up values.

       The "documentation" string is used when generating a configuration file. See below for
       details.

CLASS API

       Your config class will do the MooseX::Configuration::Trait::Object role. This adds several
       attributes and methods to your class.

   config_file attribute
       The "config_file" attribute defines the location of the configuration file. The role
       supplies a builder method that you can replace, "_build_config_file". It should return a
       string or Path::Class::File object pointing to the configuration file. It can also return
       "undef".

       If you don't provide your own builder, then the "config_file" will default to "undef".

   $config->_raw_config()
       This returns the raw hash reference as read by Config::INI::Reader. If no config file was
       defined, then this simply returns an empty hash reference.

   $config->write_config_file( ... )
       This method can be used to write a configuration file. It accepts several parameters:

       •   file

           This can be either a path or an open filehandle. The configuration text will be
           written to this file. This defaults to the value of "$self->config_file()". If no file
           is provided or already set in the object, this method will die.

       •   generated_by

           If this parameter is passed, it will be included as a comment at the top of the
           generated file.

       •   values

           This should be a hash reference of attribute names and values to write to the config
           file. It is optional.

       When writing the configuration file, any configuration item that was set in the
       configuration file originally will be set in the new file, as will any value passed in the
       "values" key. An attribute value set in the constructor or by a default will not be
       included in the generated file.

       Keys without a value will still be included in the file as a comment.

       If an attribute includes a documentation string, that string will appear as a comment
       above the key. If the attribute defines a simple scalar default, that will also be
       included in the comment, unless the default is the empty string. Finally, if the attribute
       is required, that is also mentioned in the comment.

DONATIONS

       If you'd like to thank me for the work I've done on this module, please consider making a
       "donation" to me via PayPal. I spend a lot of free time creating free software, and would
       appreciate any support you'd care to offer.

       Please note that I am not suggesting that you must do this in order for me to continue
       working on this particular software. I will continue to do so, inasmuch as I have in the
       past, for as long as it interests me.

       Similarly, a donation made in this way will probably not make me work on this software
       much more, unless I get so many donations that I can consider working on free software
       full time, which seems unlikely at best.

       To donate, log into PayPal and send money to autarch@urth.org or use the button on this
       page: http://www.urth.org/~autarch/fs-donation.html <http://www.urth.org/~autarch/fs-
       donation.html>

BUGS

       Please report any bugs or feature requests to "bug-moosex-configuration@rt.cpan.org", or
       through the web interface at <http://rt.cpan.org>.  I will be notified, and then you'll
       automatically be notified of progress on your bug as I make changes.

AUTHOR

       Dave Rolsky <autarch@urth.org>

COPYRIGHT AND LICENSE

       This software is Copyright (c) 2010 by Dave Rolsky.

       This is free software, licensed under:

         The Artistic License 2.0