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DBIx::Class::Candy(3pm) User Contributed Perl Documentation DBIx::Class::Candy(3pm)

NAME

DBIx::Class::Candy - Sugar for your favorite ORM, DBIx::Class

SYNOPSIS

 package MyApp::Schema::Result::Artist;

 use DBIx::Class::Candy -autotable => v1;

 primary_column id => {
   data_type => 'int',
   is_auto_increment => 1,
 };

 column name => {
   data_type => 'varchar',
   size => 25,
   is_nullable => 1,
 };

 has_many albums => 'A::Schema::Result::Album', 'artist_id';

 1;

DESCRIPTION

"DBIx::Class::Candy" is a simple sugar layer for definition of DBIx::Class results. Note that it may later be expanded to add sugar for more "DBIx::Class" related things. By default "DBIx::Class::Candy":
  • turns on strict and warnings
  • sets your parent class
  • exports a bunch of the package methods that you normally use to define your DBIx::Class results
  • makes a few aliases to make some of the original method names shorter or more clear
  • defines very few new subroutines that transform the arguments passed to them

It assumes a DBIx::Class::Core-like API, but you can tailor it to suit your needs.

IMPORT OPTIONS

See "SETTING DEFAULT IMPORT OPTIONS" for information on setting these schema wide.

-base

 use DBIx::Class::Candy -base => 'MyApp::Schema::Result';

The first thing you can do to customize your usage of "DBIx::Class::Candy" is change the parent class. Do that by using the "-base" import option.

-autotable

 use DBIx::Class::Candy -autotable => v1;

Don't waste your precious keystrokes typing "table 'buildings'", let "DBIx::Class::Candy" do that for you! See "AUTOTABLE VERSIONS" for what the existing versions will generate for you.

-components

 use DBIx::Class::Candy -components => ['FilterColumn'];

"DBIx::Class::Candy" allows you to set which components you are using at import time so that the components can define their own sugar to export as well. See DBIx::Class::Candy::Exports for details on how that works.

-perl5

 use DBIx::Class::Candy -perl5 => v10;

I love the new features in Perl 5.10 and 5.12, so I felt that it would be nice to remove the boiler plate of doing "use feature ':5.10'" and add it to my sugar importer. Feel free not to use this.

-experimental

 use DBIx::Class::Candy -experimental => ['signatures'];

I would like to use signatures and postfix dereferencing in all of my "DBIx::Class" classes. This makes that goal trivial.

IMPORTED SUBROUTINES

Most of the imported subroutines are the same as what you get when you use the normal interface for result definition: they have the same names and take the same arguments. In general write the code the way you normally would, leaving out the "__PACKAGE__->" part. The following are methods that are exported with the same name and arguments:

 belongs_to
 has_many
 has_one
 inflate_column
 many_to_many
 might_have
 remove_column
 remove_columns
 resultset_attributes
 resultset_class
 sequence
 source_name
 table

There are some exceptions though, which brings us to:

IMPORTED ALIASES

These are merely renamed versions of the functions you know and love. The idea is to make your result classes a tiny bit prettier by aliasing some methods. If you know your "DBIx::Class" API you noticed that in the "SYNOPSIS" I used "column" instead of "add_columns" and "primary_key" instead of "set_primary_key". The old versions work, this is just nicer. A list of aliases are as follows:

 column            => 'add_columns',
 primary_key       => 'set_primary_key',
 unique_constraint => 'add_unique_constraint',
 relationship      => 'add_relationship',

SETTING DEFAULT IMPORT OPTIONS

Eventually you will get tired of writing the following in every single one of your results:

 use DBIx::Class::Candy
   -base      => 'MyApp::Schema::Result',
   -perl5     => v12,
   -autotable => v1,
   -experimental => ['signatures'];

You can set all of these for your whole schema if you define your own "Candy" subclass as follows:

 package MyApp::Schema::Candy;

 use base 'DBIx::Class::Candy';

 sub base { $_[1] || 'MyApp::Schema::Result' }
 sub perl_version { 12 }
 sub autotable { 1 }
 sub experimental { ['signatures'] }

Note the "$_[1] ||" in "base". All of these methods are passed the values passed in from the arguments to the subclass, so you can either throw them away, honor them, die on usage, or whatever. To be clear, if you define your subclass, and someone uses it as follows:

 use MyApp::Schema::Candy
    -base => 'MyApp::Schema::Result',
    -perl5 => v18,
    -autotable => v1,
    -experimental => ['postderef'];

Your "base" method will get "MyApp::Schema::Result", your "perl_version" will get 18, your "experimental" will get "['postderef']", and your "autotable" will get 1.

SECONDARY API

has_column

There is currently a single "transformer" for "add_columns", so that people used to the Moose api will feel more at home. Note that this may go into a "Candy Component" at some point.

Example usage:

 has_column foo => (
   data_type => 'varchar',
   size => 25,
   is_nullable => 1,
 );

primary_column

Another handy little feature that allows you to define a column and set it as the primary key in a single call:

 primary_column id => {
   data_type => 'int',
   is_auto_increment => 1,
 };

If your table has multiple columns in its primary key, merely call this method for each column:

 primary_column person_id => { data_type => 'int' };
 primary_column friend_id => { data_type => 'int' };

unique_column

This allows you to define a column and set it as unique in a single call:

 unique_column name => {
   data_type => 'varchar',
   size => 30,
 };

AUTOTABLE VERSIONS

Currently there are two versions:

"v1"

It looks at your class name, grabs everything after "::Schema::Result::" (or "::Result::"), removes the "::"'s, converts it to underscores instead of camel-case, and pluralizes it. Here are some examples if that's not clear:

 MyApp::Schema::Result::Cat -> cats
 MyApp::Schema::Result::Software::Building -> software_buildings
 MyApp::Schema::Result::LonelyPerson -> lonely_people
 MyApp::DB::Result::FriendlyPerson -> friendly_people
 MyApp::DB::Result::Dog -> dogs

'singular'

It looks at your class name, grabs everything after "::Schema::Result::" (or "::Result::"), removes the "::"'s and converts it to underscores instead of camel-case. Here are some examples if that's not clear:

 MyApp::Schema::Result::Cat -> cat
 MyApp::Schema::Result::Software::Building -> software_building
 MyApp::Schema::Result::LonelyPerson -> lonely_person
 MyApp::DB::Result::FriendlyPerson -> friendly_person
 MyApp::DB::Result::Dog -> dog

Also, if you just want to be different, you can easily set up your own naming scheme. Just add a "gen_table" method to your candy subclass. The method gets passed the class name and the autotable version, which of course you may ignore. For example, one might just do the following:

 sub gen_table {
   my ($self, $class) = @_;

   $class =~ s/::/_/g;
   lc $class;
 }

Which would transform "MyApp::Schema::Result::Foo" into "myapp_schema_result_foo".

Or maybe instead of using the standard "MyApp::Schema::Result" namespace you decided to be different and do "MyApp::DB::Table" or something silly like that. You could pre-process your class name so that the default "gen_table" will still work:

 sub gen_table {
   my $self = shift;
   my $class = $_[0];

   $class =~ s/::DB::Table::/::Schema::Result::/;
   return $self->next::method(@_);
 }

AUTHOR

Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Arthur Axel "fREW" Schmidt.

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

2017-10-29 perl v5.26.0