Data::Mapper

Transcript

1. Data::Mapper Kyoto.pm #1 2012-03-17 id:antipop / @kentaro

2. id:antipop @kentaro Programmer Ikemen Perler/Emacser/Hatena Kentaro Kuribayashi One of Representatives

   in Japanese IT industry
3. None
4. None

5. What’s Data::Mapper?

6. Sort of an ORM Simple & Clean

7. Why Yet Another ORM?

8. Using DBI Directly Full Stack ORM The Middle Way

9. API Design Simple Convention Performance Model for Every Data

10. An implementation of Data Mapper Pattern

11. Maps Data Between DB and In-memory Data Isolating Them from

    Each Other http://martinfowler.com/eaaCatalog/dataMapper.html

12. An object that wraps a row in a database table

    or view, encapsulates the database access, and adds domain logic on that data. http://martinfowler.com/eaaCatalog/activeRecord.html

13. Characters

14. Adapter Mapper Data

15. Mapper User Blog Entry User Blog Entry Adapter Data

16. Mapper User Blog Entry User Blog Entry Adapter Data

17. Adapter Database External API Memcached etc.

18. Data Data::Mapper::Data POPO (Plain Old Perl Object)

19. Mapper HashRef to HashRef Maps by Schema

20. Data::Mapper Convention

21. Create Find Search Update Delete Basic CRUD

22. Adapter Retrieves Data from Somewhere and Returns It as a

    HashRef Data Hash-based Object Knows Schema Info

23. Table <-> Data user <-> User user_info <-> UserInfo Table

    <-> Data Class user <-> D::M::Data::User user_info <-> D::M::Data::UserInfo (Customizable by D::M#data_class()

24. Usage

25. my $handler = DBIx::Handler->new(...); my $adapter = Data::Mapper::Adapter::DBI->new({ driver =>

    sub { $handler->dbh } }); my $mapper = My::Mapper->new({ adapter => $adapter }); Instanciate

26. Mapper Adapter DBI API etc. adapter() driver()

27. my $data = $mapper->create(user => { name => 'kentaro', age

    => 34 }); #=> $data is a Data::Mapper::Data- based object Create

28. $data = $mapper->find(user => { name => 'kentaro' }); #=>

    $data is a Data::Mapper::Data- based object Retrieve

29. $result = $mapper->search(user => { age => 34 }, {

    order_by => 'id DESC' }); #=> $result is an ArrayRef of Data::Mapper::Data-based object Search

30. # Updates params like below $data->param(age => 35); my $sth

    = $mapper->update($data); $sth->rows; #=> 1 Update

31. my $sth = $mapper->delete($data); $sth->rows; #=> 1 Delete

32. # Data to Table sub mapped_params { my ($self, $data)

    = @_; my $table = $self- >to_table_name($data); my $schema = $self->adapter->schemata- >{$table} or Carp::croak("no such table: $table"); # snip } Schema

33. Advanced Usage

34. sub create { my ($self, $name, $args) = @_; my

    $content_type = File::MimeInfo::Magic::mimetype($args->{filename}); # $self->driver is a Fule::S3 object my $res = $self->driver->create_object_from_file( $name, $args->{key}, $args->{filename}, { content_type => $content_type, 'x-amz-acl' => $args->{acl}, } ); +{ bucket => $name, key => $args->{key}, type => $content_type, } } Adapter for External API

35. # How can we implement below? $user->blog; $blog->entries; Relation (Under

    Considering)

36. # Mapper sub map_data { # snip ... my $obj

    = $data_class->new($data); $obj->SOMESPECIALMETHOD($self) if $obj->isa('Data::Mapper::Data'); $obj; } # Data sub SOMESPECIALMETHOD { my ($self, $mapper) = @_; $self->{author} = $mapper->find(author => { id => $self->param('author_id') }); } Relation (Idea 1)

37. # Data sub mapper { my ($self, $mapper) = @_;

    $self->{_mapper} = $mapper if defined $mapper; $self->{_mapper}; } # Mapper sub map_data { my $self = shift; my $data = $self->SUPER::map_data(@_); $data->mapper($self); $data; } Relation (Idea 2)

38. # Data sub mapper { my ($self, $mapper) = @_;

    $self->{_mapper} = $mapper if defined $mapper; $self->{_mapper}; } # Mapper sub map_data { my $self = shift; my $data = $self->SUPER::map_data(@_); $data->mapper($self); $data; } Relation (Idea 2)

39. TODO: Relation (But Should It Be Supported by Module?) Master/Slave

    Unit of Work

40. Available on GitHub https://github.com/kentaro/data-mapper

41. Data::Mapper: Recap • Is a Simple ORM • Just Defines

    Minimum Conventions • Deals with Any Data from Anywhere

42. Any Questions?