NAME

Fey::ORM::Policy - Declarative policies for Fey::ORM using classes

VERSION

version 0.46

SYNOPSIS

  package MyApp::Policy;

  use strict;
  use warnings;

  use Fey::ORM::Policy;
  use Lingua::EN::Inflect qw( PL_N );

  transform_all
         matching { $_[0]->type() eq 'date' }

      => inflate  { return unless defined $_[1];
                    return DateTime::Format::Pg->parse_date( $_[1] ) }

      => deflate  { defined $_[1] && ref $_[1]
                      ? DateTime::Format::Pg->format_date( $_[1] )
                      : $_[1] };

  transform_all
         matching { $_[0]->name() eq 'email_address' }

      => inflate  { return unless defined $_[1];
                    return Email::Address->parse( $_[1] ) }

      => deflate  { defined $_[1] && ref $_[1]
                      ? Email::Address->as_string
                      : $_[1] };

  has_one_namer  { my $name = $_[0]->name();
                   my @parts = map { lc } ( $name =~ /([A-Z][a-z]+)/g );

                   return join q{_}, @parts; };

  has_many_namer { my $name = $_[0]->name();
                   my @parts = map { lc } ( $name =~ /([A-Z][a-z]+)/g );

                   $parts[-1] = PL_N( $parts[-1] );

                   return join q{_}, @parts; };

  package User;

  use Fey::ORM::Table;

  has_policy 'MyApp::Policy';

  has_table ...;

DESCRIPTION

This module allows you to declare a policy for your Fey::ORM::Table-using classes.

A policy can define transform rules which can be applied to matching columns, as well as a naming scheme for has_one and has_many methods. This allows you to spare yourself some drudgery, and allows you to consolidate decisions (like "all date type columns return a DateTime object") in a single place.

FUNCTIONS

This module exports a bunch of sugar functions into your namespace so you can define your policy in a declarative manner:

transform_all

This should be followed by a matching sub reference, and one of an inflate or deflate sub.

matching { ... }

This function takes a subroutine reference that will be called and passed a Fey::Column object as its argument. This sub should look at the column and return true if the associated inflate/deflate should be applied to the column.

Note that the matching subs are checked in the order they are defined by transform_all(), and the first one wins.

inflate { ... }

An inflator sub for the associated transform. See Fey::ORM::Table for more details on transforms.

deflate { ... }

A deflator sub for the associated transform. See Fey::ORM::Table for more details on transforms.

has_one_namer { ... }

A subroutine reference which will be used to generate a name for has_one() methods when a name is not explicitly provided.

This sub will receive the foreign table as its first argument, and the associated FK object as the second argument. In most cases, the foreign table will probably be sufficient to generate a name.

has_many_namer { ... }

Just like the has_one_namer(), but is called for naming has_many() methods.

Policy

This methods returns the Fey::Object::Policy object for your policy class. This method allows Fey::ORM::Table to go get a policy object from a policy class name.

AUTHOR

Dave Rolsky <autarch@urth.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2011 by Dave Rolsky.

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