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NAME

DBIx::Class::EasyFixture - Easy fixtures with DBIx::Class

VERSION

version 0.13

SYNOPSIS

package My::Fixtures;
use Moo;    # (Moose is also fine)
extends 'DBIx::Class::EasyFixture';

sub get_definition    { ... }
sub all_fixture_names { ... }

And in your test code:

my $fixtures    = My::Fixtures->new( { schema => $schema } );
my $dbic_object = $fixtures->load('some_fixture');

# run your tests

$fixtures->unload;

Note that unload will be called for you if your fixture object falls out of scope.

DESCRIPTION

The latest version of this is always at https://github.com/Ovid/dbix-class-easyfixture.

This is ALPHA code. Documentation is on its way, including a tutorial. For now, you'll have to read the tests. You can read t/lib/My/Fixtures.pm to see how fixtures are defined.

I wanted an easier way to load fixtures for DBIx::Class code. I looked at DBIx::Class::Fixtures and it made a lot of assumptions that, while appropriate for some, is not what I wanted (such as the necessity of storing fixtures in JSON files), and had a reliance on knowing the values of primary keys, I wrote this to make it easier to define and load DBIx::Class fixtures for tests.

METHODS

new

my $fixtures = Subclass::Of::DBIx::Class::EasyFixture->new({
    schema => $dbix_class_schema_instance,
});

This creates and returns a new instance of your DBIx::Class::EasyFixture subclass. All fixture definitions are validated at this time and the constructor will croak() with a useful error message upon validation failure.

all_fixture_names

my @fixture_names = $fixtures->all_fixture_names;

Must overridden in your subclass. Should return a list (not an array ref!) of all fixture names available. This is used internally to generate error messages if a fixture attempts to reference a non-existent fixture in its next or requires section.

get_definition

my $definition = $fixtures->get_definition($fixture_name);

Must be overridden in a subclass. Should return the fixture definition for the fixture name passed in. Should return undef if the fixture is not found.

get_result

my $dbic_result_object = $fixtures->get_result($fixture_name);

Returns the DBIx::Class::Result object for the given fixture name. Will carp if the fixture wasn't loaded (this may become a fatal error in future versions).

load

my @dbic_objects = $fixtures->load(@list_of_fixture_names);

Attempts to load all fixtures passed to it. If a transaction has not already been started, it will be started now. This method may be called multiple times and it returns the fixtures loaded. If called in scalar context, only returns the first fixture loaded.

unload

$fixtures->unload;

Rolls back the transaction started with load

is_loaded

if ( $fixtures->is_loaded($fixture_name) ) {
    ...
}

Returns a boolean value indicating whether or not the given fixture was loaded.

*Note*: Originally this method was called fixture_loaded. That was a bad name. However, fixture_loaded still works as an alias to is_loaded.

TRANSACTIONS

If you attempt to load a fixture, a transaction is started and it will be rolled back when you call unload() or when the fixture object falls out of scope. If, for some reason, you do not want transactions (for example, if you need to control them manually), you can use a true value with the no_transactions argument.

my $fixtures = My::Fixtures->new(
    schema          => $schema,
    no_transactions => 1,
);

FIXTURES

If the following is unclear, see DBIx::Class::EasyFixture::Tutorial.

The get_definition($fixture_name) method must always return a fixture definition. The definition must be either a fixture group or a fixture builder.

A fixture group is an array reference containing a list of fixture names. For example, $fixture->get_definition('all_people') might return:

[qw/ person_1 person_2 person_2 /]

A fixture builder must return a hash reference with the one or more of the following keys:

  • new (required)

    A DBIx::Class result source name.

    {
        new   => 'Person',
        using => {
            name  => 'Bob',
            email => 'bob@example.com',
        }
    }

    Internally, the above will do something similar to this:

    $schema->resultset($definition->{name})
           ->create($definition->{using});
  • using (required)

    A hashref of key/value pairs that will be used to create the DBIx::Class result source referred to by the new key.

    {
        new   => 'Person',
        using => {
            name  => 'Bob',
            email => 'bob@example.com',
        }
    }
  • next (optional)

    If present, this must point to an array reference of fixture names (in other words, a fixture group). These fixtures will then be built after the current fixture is built.

    {
        new   => 'Person',
        using => {
            name  => 'Bob',
            email => 'bob@example.com',
        },
        next => [@list_of_fixture_names],
    }
  • requires (optional)

    Must point to either a scalar of an attribute name or a hash mapping of attribute names.

    Many fixtures require data from another fixture. For example, a customer might require a person object being built and the following won't work:

    {
        new   => 'Customer',
        using => {
            first_purchase => $datetime_object,
            person_id      => 'some_person.person_id',
        }
    }

    Assuming we already have a Person fixture defined and it's named some_person and its ID is named id, we can do this:

    {
        new      => 'Customer',
        using    => { first_purchase => $datetime_object },
        requires => {
            some_person => {
                our   => 'person_id',
                their => 'id',
            },
        },
    }

    If you prefer, you can inline the requires into the using key. You may find this syntax cleaner:

    {
        new      => 'Customer',
        using    => {
            first_purchase => $datetime_object,
            person_id      => { some_person => 'id' },
        },
    }

    The our key refers to the attribute for the Customer fixture and the their key refers to the attribute of the Person fixture. As a convenience, if both attributes have the same name, you can omit that hashref and just use the attribute name:

    {
        new      => 'Customer',
        using    => { first_purchase => $datetime_object },
        requires => {
            some_person => 'person_id',
        },
    }

    And multiple requires can be specified:

    {
        new      => 'Customer',
        using    => { first_purchase => $datetime_object },
        requires => {
            some_person     => 'person_id',
            primary_contact => 'contact_id',
        },
    }

    Or you can skip the requires block entirely and write the above like this (which is now the preferred syntax, but whatever floats your boat):

    {
        new      => 'Customer',
        using    => {
            first_purchase => $datetime_object,
            person_id      => { some_person     => 'person_id' },
            contact_id     => { primary_contact => 'contact_id' },
        },
    }

    If both the current fixture and the other fixture it requires have the same name for the attribute, a reference to the other fixture name (scalar reference) will suffice:

    {
        new      => 'Customer',
        using    => {
            first_purchase => $datetime_object,
            person_id      => \'some_person',
            contact_id     => \'primary_contact',
        },
    }
    The above will construct the fixture like this:
    
    $schema->resultset('Customer')->create({
        first_purchase  => $datetime_object,
        person_id       => $person->person_id,
        primary_contact => $contact->contact_id,
    });

When writing a fixture builder, remember that requires are always built before the current fixture and next is also built after the current fixture.

TUTORIAL

See DBIx::Class::EasyFixture::Tutorial.

AUTHOR

Curtis "Ovid" Poe, <ovid at cpan.org>

TODO

  • Prevent circular fixtures

    Currently it's very easy to define circular dependencies. We'll worry about that later when it becomes more clear how to best handle them.

  • Better load information

    Track what fixtures are requested and what fixtures are loaded (and in which order). This makes for better error reporting.

AUTHOR

Curtis "Ovid" Poe <ovid@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Curtis "Ovid" Poe.

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