1 package DBIx::Class::Schema;
7 use base qw/Class::Data::Inheritable/;
8 use base qw/DBIx::Class/;
10 __PACKAGE__->load_components(qw/Exception/);
11 __PACKAGE__->mk_classdata('class_registrations' => {});
15 DBIx::Class::Schema - composable schemas
23 use base qw/DBIx::Class::Schema/;
25 __PACKAGE__->load_classes(qw/Foo Bar Baz/);
29 package My::Schema::Foo;
31 use base qw/DBIx::Class/;
33 __PACKAGE__->load_components(qw/Core PK::Auto::Pg/); # for example
34 __PACKAGE__->table('foo');
41 My::Schema->compose_connection('My::DB', $dsn, $user, $pass, $attrs);
45 my @obj = My::DB::Foo->search({}); # My::DB::Foo isa My::Schema::Foo My::DB
49 Creates database classes based on a schema. This allows you to have more than
50 one concurrent connection using the same database classes, by making
51 subclasses under a new namespace for each connection. If you only need one
52 class, you should probably use L<DBIx::Class::DB> directly instead.
54 NB: If you're used to L<Class::DBI> it's worth reading the L</SYNOPSIS>
55 carefully as DBIx::Class does things a little differently. Note in
56 particular which module inherits off which.
62 =item register_class <component> <component_class>
64 Registers the class in the schema's class_registrations. This is a hash
65 containing database classes, keyed by their monikers. It's used by
66 compose_connection to create/modify all the existing database classes.
71 my ($class, $name, $to_register) = @_;
72 my %reg = %{$class->class_registrations};
73 $reg{$name} = $to_register;
74 $class->class_registrations(\%reg);
77 =item registered_classes
79 Simple read-only accessor for the schema's registered classes. See
80 register_class above if you want to modify it.
85 sub registered_classes {
86 return values %{shift->class_registrations};
89 =item load_classes [<classes>}
91 Uses L<Module::Find> to find all classes under the database class' namespace,
92 or uses the classes you select. Then it loads the component (using L<use>),
93 and registers them (using B<register_class>);
99 my @comp = grep { $_ !~ /^#/ } @_;
101 eval "require Module::Find;";
102 $class->throw("No arguments to load_classes and couldn't load".
103 " Module::Find ($@)") if $@;
104 @comp = map { substr $_, length "${class}::" }
105 Module::Find::findallmod($class);
107 foreach my $comp (@comp) {
108 my $comp_class = "${class}::${comp}";
109 eval "use $comp_class"; # If it fails, assume the user fixed it
110 $class->register_class($comp => $comp_class);
114 =item compose_connection <target> <@db_info>
116 This is the most important method in this class. it takes a target namespace,
117 as well as dbh connection info, and creates a L<DBIx::Class::DB> class as
118 well as subclasses for each of your database classes in this namespace, using
121 It will also setup a ->table method on the target class, which lets you
122 resolve database classes based on the schema component name, for example
124 MyApp::DB->table('Foo') # returns MyApp::DB::Foo,
125 # which ISA MyApp::Schema::Foo
127 This is the recommended API for accessing Schema generated classes, and
128 using it might give you instant advantages with future versions of DBIC.
132 sub compose_connection {
133 my ($class, $target, @info) = @_;
134 my $conn_class = "${target}::_db";
135 $class->setup_connection_class($conn_class, @info);
136 my %reg = %{ $class->class_registrations };
139 while (my ($comp, $comp_class) = each %reg) {
140 my $target_class = "${target}::${comp}";
141 $class->inject_base($target_class, $comp_class, $conn_class);
142 $target_class->table($comp_class->table);
143 @map{$comp, $comp_class} = ($target_class, $target_class);
147 *{"${target}::class"} =
149 my ($class, $to_map) = @_;
150 return $map{$to_map};
152 *{"${target}::classes"} = sub { return \%map; };
154 $conn_class->class_resolver($target);
157 =item setup_connection_class <$target> <@info>
159 Sets up a database connection class to inject between the schema
160 and the subclasses the schema creates.
164 sub setup_connection_class {
165 my ($class, $target, @info) = @_;
166 $class->inject_base($target => 'DBIx::Class::DB');
167 #$target->load_components('DB');
168 $target->connection(@info);
177 Matt S. Trout <mst@shadowcatsystems.co.uk>
181 You may distribute this code under the same terms as Perl itself.