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NAME

Catalyst::Model::DBIC::Schema - DBIx::Class::Schema Model Class

SYNOPSIS

Manual creation of a DBIx::Class::Schema and a Catalyst::Model::DBIC::Schema:

  1. Create the DBIx:Class schema in MyApp/Schema/FilmDB.pm:

      package MyApp::Schema::FilmDB;
      use base qw/DBIx::Class::Schema/;
    
      __PACKAGE__->load_classes(qw/Actor Role/);
  2. Create some classes for the tables in the database, for example an Actor in MyApp/Schema/FilmDB/Actor.pm:

      package MyApp::Schema::FilmDB::Actor;
      use base qw/DBIx::Class/
    
      __PACKAGE__->load_components(qw/Core/);
      __PACKAGE__->table('actor');
    
      ...

    and a Role in MyApp/Schema/FilmDB/Role.pm:

      package MyApp::Schema::FilmDB::Role;
      use base qw/DBIx::Class/
    
      __PACKAGE__->load_components(qw/Core/);
      __PACKAGE__->table('role');
    
      ...    

    Notice that the schema is in MyApp::Schema, not in MyApp::Model. This way it's usable as a standalone module and you can test/run it without Catalyst.

  3. To expose it to Catalyst as a model, you should create a DBIC Model in MyApp/Model/FilmDB.pm:

      package MyApp::Model::FilmDB;
      use base qw/Catalyst::Model::DBIC::Schema/;
    
      __PACKAGE__->config(
          schema_class => 'MyApp::Schema::FilmDB',
          connect_info => {
                            dsn => "DBI:...",
                            user => "username",
                            password => "password",
                          }
      );

    See below for a full list of the possible config parameters.

Now you have a working Model which accesses your separate DBIC Schema. This can be used/accessed in the normal Catalyst manner, via $c->model():

  my $actor = $c->model('FilmDB::Actor')->find(1);

You can also use it to set up DBIC authentication with Catalyst::Authentication::Store::DBIx::Class in MyApp.pm:

  package MyApp;

  use Catalyst qw/... Authentication .../;

  ...

  __PACKAGE__->config->{authentication} = 
                {  
                    default_realm => 'members',
                    realms => {
                        members => {
                            credential => {
                                class => 'Password',
                                password_field => 'password',
                                password_type => 'hashed'
                                password_hash_type => 'SHA-256'
                            },
                            store => {
                                class => 'DBIx::Class',
                                user_model => 'DB::User',
                                role_relation => 'roles',
                                role_field => 'rolename',                   
                            }
                        }
                    }
                };

$c->model('Schema::Source') returns a DBIx::Class::ResultSet for the source name parameter passed. To find out more about which methods can be called on a ResultSet, or how to add your own methods to it, please see the ResultSet documentation in the DBIx::Class distribution.

Some examples are given below:

  # to access schema methods directly:
  $c->model('FilmDB')->schema->source(...);

  # to access the source object, resultset, and class:
  $c->model('FilmDB')->source(...);
  $c->model('FilmDB')->resultset(...);
  $c->model('FilmDB')->class(...);

  # For resultsets, there's an even quicker shortcut:
  $c->model('FilmDB::Actor')
  # is the same as $c->model('FilmDB')->resultset('Actor')

  # To get the composed schema for making new connections:
  my $newconn = $c->model('FilmDB')->composed_schema->connect(...);

  # Or the same thing via a convenience shortcut:
  my $newconn = $c->model('FilmDB')->connect(...);

  # or, if your schema works on different storage drivers:
  my $newconn = $c->model('FilmDB')->composed_schema->clone();
  $newconn->storage_type('::LDAP');
  $newconn->connection(...);

  # and again, a convenience shortcut
  my $newconn = $c->model('FilmDB')->clone();
  $newconn->storage_type('::LDAP');
  $newconn->connection(...);

DESCRIPTION

This is a Catalyst Model for DBIx::Class::Schema-based Models. See the documentation for Catalyst::Helper::Model::DBIC::Schema for information on generating these Models via Helper scripts.

When your Catalyst app starts up, a thin Model layer is created as an interface to your DBIC Schema. It should be clearly noted that the model object returned by $c->model('FilmDB') is NOT itself a DBIC schema or resultset object, but merely a wrapper proving methods to access the underlying schema.

In addition to this model class, a shortcut class is generated for each source in the schema, allowing easy and direct access to a resultset of the corresponding type. These generated classes are even thinner than the model class, providing no public methods but simply hooking into Catalyst's model() accessor via the ACCEPT_CONTEXT mechanism. The complete contents of each generated class is roughly equivalent to the following:

  package MyApp::Model::FilmDB::Actor
  sub ACCEPT_CONTEXT {
      my ($self, $c) = @_;
      $c->model('FilmDB')->resultset('Actor');
  }

In short, there are three techniques available for obtaining a DBIC resultset object:

  # the long way
  my $rs = $c->model('FilmDB')->schema->resultset('Actor');

  # using the shortcut method on the model object
  my $rs = $c->model('FilmDB')->resultset('Actor');

  # using the generated class directly
  my $rs = $c->model('FilmDB::Actor');

In order to add methods to a DBIC resultset, you cannot simply add them to the source (row, table) definition class; you must define a separate custom resultset class. See "Predefined searches" in DBIx::Class::Manual::Cookbook for more info.

CONFIG PARAMETERS

Any options in your config not listed here are passed to your schema.

schema_class

This is the classname of your DBIx::Class::Schema Schema. It needs to be findable in @INC, but it does not need to be inside the Catalyst::Model:: namespace. This parameter is required.

connect_info

This is an arrayref of connection parameters, which are specific to your storage_type (see your storage type documentation for more details). If you only need one parameter (e.g. the DSN), you can just pass a string instead of an arrayref.

This is not required if schema_class already has connection information defined inside itself (which isn't highly recommended, but can be done)

For DBIx::Class::Storage::DBI, which is the only supported storage_type in DBIx::Class at the time of this writing, the parameters are your dsn, username, password, and connect options hashref.

See "connect_info" in DBIx::Class::Storage::DBI for a detailed explanation of the arguments supported.

Examples:

  connect_info => {
    dsn => 'dbi:Pg:dbname=mypgdb',
    user => 'postgres',
    password => ''
  }

  connect_info => {
    dsn => 'dbi:SQLite:dbname=foo.db',
    on_connect_do => [
      'PRAGMA synchronous = OFF',
    ]
  }

  connect_info => {
    dsn => 'dbi:Pg:dbname=mypgdb',
    user => 'postgres',
    password => '',
    pg_enable_utf8 => 1,
    on_connect_do => [
      'some SQL statement',
      'another SQL statement',
    ],
  }

Or using Config::General:

    <Model::FilmDB>
        schema_class   MyApp::Schema::FilmDB
        traits Caching
        <connect_info>
            dsn   dbi:Pg:dbname=mypgdb
            user   postgres
            password ""
            auto_savepoint 1
            quote_char """
            on_connect_do   some SQL statement
            on_connect_do   another SQL statement
        </connect_info>
        user_defined_schema_accessor foo
    </Model::FilmDB>

or

    <Model::FilmDB>
        schema_class   MyApp::Schema::FilmDB
        connect_info   dbi:SQLite:dbname=foo.db
    </Model::FilmDB>

Or using YAML:

  Model::MyDB:
      schema_class: MyDB
      traits: Caching
      connect_info:
          dsn: dbi:Oracle:mydb
          user: mtfnpy
          password: mypass
          LongReadLen: 1000000
          LongTruncOk: 1
          on_connect_call: 'datetime_setup'
          quote_char: '"'

The old arrayref style with hashrefs for DBI then DBIx::Class options is also supported:

  connect_info => [
    'dbi:Pg:dbname=mypgdb',
    'postgres',
    '',
    {
      pg_enable_utf8 => 1,
    },
    {
      auto_savepoint => 1,
      on_connect_do => [
        'some SQL statement',
        'another SQL statement',
      ],
    }
  ]

traits

Array of Traits to apply to the instance. Traits are Moose::Roles.

They are relative to the MyApp::TraitFor::Model::DBIC::Schema::, then the Catalyst::TraitFor::Model::DBIC::Schema:: namespaces, unless prefixed with + in which case they are taken to be a fully qualified name. E.g.:

    traits Caching
    traits +MyApp::TraitFor::Model::Foo

A new instance is created at application time, so any consumed required attributes, coercions and modifiers will work.

Traits are applied at "COMPONENT" in Catalyst::Component time using CatalystX::Component::Traits.

ref $self will be an anon class if any traits are applied, $self->_original_class_name will be the original class.

When writing a Trait, interesting points to modify are BUILD, "setup" and "ACCEPT_CONTEXT".

Traits that come with the distribution:

Catalyst::TraitFor::Model::DBIC::Schema::Caching
Catalyst::TraitFor::Model::DBIC::Schema::Replicated

storage_type

Allows the use of a different storage_type than what is set in your schema_class (which in turn defaults to ::DBI if not set in current DBIx::Class). Completely optional, and probably unnecessary for most people until other storage backends become available for DBIx::Class.

ATTRIBUTES

The keys you pass in the model configuration are available as attributes.

Other attributes available:

connect_info

Your connect_info args normalized to hashref form (with dsn/user/password.) See "connect_info" in DBIx::Class::Storage::DBI for more info on the hashref form of "connect_info".

model_name

The model name Catalyst uses to resolve this model, the part after ::Model:: or ::M:: in your class name. E.g. if your class name is MyApp::Model::DB the "model_name" will be DB.

_default_cursor_class

What to reset your "cursor_class" in DBIx::Class::Storage::DBI to if a custom one doesn't work out. Defaults to DBIx::Class::Storage::DBI::Cursor.

ATTRIBUTES FROM MooseX::Traits::Pluggable

_original_class_name

The class name of your model before any "traits" are applied. E.g. MyApp::Model::DB.

_traits

Unresolved arrayref of traits passed in the config.

_resolved_traits

Traits you used resolved to full class names.

METHODS

Methods not listed here are delegated to the connected schema used by the model instance, so the following are equivalent:

    $c->model('DB')->schema->my_accessor('foo');
    # or
    $c->model('DB')->my_accessor('foo');

Methods on the model take precedence over schema methods.

new

Instantiates the Model based on the above-documented ->config parameters. The only required parameter is schema_class. connect_info is required in the case that schema_class does not already have connection information defined for it.

schema

Accessor which returns the connected schema being used by the this model. There are direct shortcuts on the model class itself for schema->resultset, schema->source, and schema->class.

composed_schema

Accessor which returns the composed schema, which has no connection info, which was used in constructing the schema above. Useful for creating new connections based on the same schema/model. There are direct shortcuts from the model object for composed_schema->clone and composed_schema->connect

clone

Shortcut for ->composed_schema->clone

connect

Shortcut for ->composed_schema->connect

source

Shortcut for ->schema->source

class

Shortcut for ->schema->class

resultset

Shortcut for ->schema->resultset

storage

Provides an accessor for the connected schema's storage object. Used often for debugging and controlling transactions.

setup

Called at BUILD time before configuration, but after "connect_info" is set. To do something after configuuration use after BUILD =>.

ACCEPT_CONTEXT

Point of extension for doing things at $c->model time with context, returns the model instance, see "ACCEPT_CONTEXT" in Catalyst::Manual::Intro for more information.

ENVIRONMENT

CMDS_NO_SOURCES

Set this variable if you will be using schemas with no sources (tables) to disable the warning. The warning is there because this is usually a mistake.

SEE ALSO

General Catalyst Stuff:

Catalyst::Manual, Catalyst::Test, Catalyst::Request, Catalyst::Response, Catalyst::Helper, Catalyst,

Stuff related to DBIC and this Model style:

DBIx::Class, DBIx::Class::Schema, DBIx::Class::Schema::Loader, Catalyst::Helper::Model::DBIC::Schema, CatalystX::Component::Traits, MooseX::Traits::Pluggable

Traits:

Catalyst::TraitFor::Model::DBIC::Schema::Caching, Catalyst::TraitFor::Model::DBIC::Schema::Replicated

AUTHOR

Brandon L Black blblack at gmail.com

CONTRIBUTORS

caelum: Rafael Kitover rkitover at cpan.org

Dan Dascalescu dandv at cpan.org

Aran Deltac bluefeet@cpan.org

COPYRIGHT

Copyright (c) 2006 - 2009 the Catalyst::Model::DBIC::Schema "AUTHOR" and "CONTRIBUTORS" as listed above.

LICENSE

This program is free software. You can redistribute it and/or modify it under the same terms as Perl itself.