NAME

       Catalyst::Model::Adaptor - use a plain class as a Catalyst model

SYNOPSIS

       Given a good old perl class like:

           package NotMyApp::SomeClass;
           use Moose; # to provide "new"
           sub method { 'yay' }

       Wrap it with a Catalyst model:

           package MyApp::Model::SomeClass;
           use base 'Catalyst::Model::Adaptor';
           __PACKAGE__->config( class => 'NotMyApp::SomeClass' );

       Then you can use "NotMyApp::SomeClass" from your Catalyst app:

           sub action :Whatever {
               my ($self, $c) = @_;
               my $someclass = $c->model('SomeClass');
               $someclass->method; # yay
           }

       Note that "NotMyApp::SomeClass" is instantiated at application startup time.  If you want
       the adapted class to be created for call to "$c->model", see Catalyst::Model::Factory
       instead.  If you want the adapted class to be created once per request, see
       Catalyst::Model::Factory::PerRequest.

DESCRIPTION

       The idea is that you don't want your Catalyst model to be anything other than a line or
       two of glue.  Using this module ensures that your Model classes are separate from your
       application and therefore are well-abstracted, reusable, and easily testable.

       Right now there are too many modules on CPAN that are Catalyst-specific.  Most of the
       models would be better written as a class that handles most of the functionality with just
       a bit of glue to make it work nicely with Catalyst.  This module aims to make integrating
       your class with Catalyst trivial, so you won't have to do any extra work to make your
       model generic.

       For a good example of a Model that takes the right design approach, take a look at
       Catalyst::Model::DBIC::Schema.  All it does is glues an existing DBIx::Class::Schema to
       Catalyst.  It provides a bit of sugar, but no actual functionality.  Everything important
       happens in the "DBIx::Class::Schema" object.

       The end result of that is that you can use your app's DBIC schema without ever thinking
       about Catalyst.  This is a Good Thing.

       Catalyst is glue, not a way of life!

CONFIGURATION

       Subclasses of this model accept the following configuration keys, which can be hard-coded
       like:

          package MyApp::Model::SomeClass;
          use base 'Catalyst::Model::Adaptor';
          __PACKAGE__->config( class => 'NotMyApp::SomeClass' );

       Or be specified as application config:

          package MyApp;
          MyApp->config->{'Model::SomeClass'} = { class => 'NotMyApp::SomeClass' };

       Or in your ConfigLoader-loaded config file:

          ---
          Model::SomeClass:
            class: NotMyApp::SomeClass
            args:
              foo: ...
              bar: ...

       This is exactly like every other Catalyst component, so you should already know this.

       Anyway, here are the options:

   class
       This is the name of the class you're adapting to Catalyst.  It MUST be specified.

       Your application will die horribly if it can't require this package.

   constructor
       This is the name of the class method in "class" that will create an instance of the class.
       It defaults to "new".

       Your application will die horribly if it can't call this method.

   args
       This is a hashref of arguments to pass to the constructor of "class".  It is optional, of
       course.  If you omit it, nothing is passed to the constructor (as opposed to "{}", an
       empty hashref).

METHODS

       There are no methods that you call directly.  When you call "$c->model" on a model that
       subclasses this, you'll get back an instance of the class being adapted, not this model.

       These methods are called by Catalyst:

   COMPONENT
       Setup this component.

CUSTOMIZING THE PROCESS

       By default, the instance of your adapted class is instantiated like this:

           my $args = $self->prepare_arguments($app); # $app sometimes called $c
           $adapted_class->$constructor($self->mangle_arguments($args));

       Since a static hashref of arguments may not be what $class needs, you can override the
       following methods to change what $args is.

   prepare_arguments
       This method is passed the entire configuration for the class and the Catalyst application,
       and returns the hashref of arguments to be passed to the constructor.  If you need to get
       dynamic data out of your application to pass to the consturctor, do it here.

       By default, this method returns the "args" configuration key.

       Example:

           sub prepare_arguments {
               my ($self, $app) = @_; # $app sometimes written as $c
               return { foobar => $app->config->{foobar}, baz => $self->{baz} };
           }

   mangle_arguments
       This method is passed the hashref from "prepare_arguments", mangles them into a form that
       your constructor will like, and returns the mangled form.  If your constuctor wants a list
       instead of a hashref, this is your opportunity to do the conversion.

       Example:

           sub mangle_arguments {
               my ($self, $args) = @_;
               return %$args; # now the args are a plain list
           }

       If you need to do more than this, you might as well just write the whole class yourself.
       This module is designed to make the common case work with 1 line of code.  For special
       needs, it's easier to just write the model yourself.

SEE ALSO

       If you need a new instance returned each time "$c->model" is called, use
       Catalyst::Model::Factory instead.

       If you need to have exactly one instance created per request, use
       Catalyst::Model::Factory::PerRequest instead.

AUTHOR

       Jonathan Rockway "<jrockway@cpan.org>"

LICENSE

       This module is Copyright (c) 2007 Jonathan Rockway.  You may use, modify, and redistribute
       it under the same terms as Perl itself.