1 package DBIx::Class::Schema;
6 use Carp::Clan qw/^DBIx::Class/;
7 use UNIVERSAL::require;
9 use base qw/DBIx::Class/;
11 __PACKAGE__->mk_classdata('class_mappings' => {});
12 __PACKAGE__->mk_classdata('source_registrations' => {});
13 __PACKAGE__->mk_classdata('storage_type' => '::DBI');
14 __PACKAGE__->mk_classdata('storage');
18 DBIx::Class::Schema - composable schemas
23 use base qw/DBIx::Class::Schema/;
25 # load My::Schema::Foo, My::Schema::Bar, My::Schema::Baz
26 __PACKAGE__->load_classes(qw/Foo Bar Baz/);
28 package My::Schema::Foo;
29 use base qw/DBIx::Class/;
30 __PACKAGE__->load_components(qw/PK::Auto::Pg Core/); # for example
31 __PACKAGE__->table('foo');
33 my $schema1 = My::Schema->connect(
40 my $schema2 = My::Schema->connect( ... );
42 # fetch objects using My::Schema::Foo
43 my $resultset = $schema1->resultset('Foo')->search( ... );
44 my @objects = $schema2->resultset('Foo')->search( ... );
48 Creates database classes based on a schema. This is the recommended way to
49 use L<DBIx::Class> and allows you to use more than one concurrent connection
52 NB: If you're used to L<Class::DBI> it's worth reading the L</SYNOPSIS>
53 carefully as DBIx::Class does things a little differently. Note in
54 particular which module inherits off which.
58 =head2 register_class <moniker> <component_class>
60 Registers a class which isa ResultSourceProxy; equivalent to calling
62 $schema->register_source($moniker, $class->result_source_instance);
67 my ($self, $moniker, $to_register) = @_;
68 $self->register_source($moniker => $to_register->result_source_instance);
71 =head2 register_source <moniker> <result source>
73 Registers the result source in the schema with the given moniker
78 my ($self, $moniker, $source) = @_;
79 my %reg = %{$self->source_registrations};
80 $reg{$moniker} = $source;
81 $self->source_registrations(\%reg);
82 $source->schema($self);
83 if ($source->result_class) {
84 my %map = %{$self->class_mappings};
85 $map{$source->result_class} = $moniker;
86 $self->class_mappings(\%map);
92 my $class = $schema->class('Foo');
94 Retrieves the result class name for a given result source
99 my ($self, $moniker) = @_;
100 return $self->source($moniker)->result_class;
105 my $source = $schema->source('Foo');
107 Returns the result source object for the registered name
112 my ($self, $moniker) = @_;
113 my $sreg = $self->source_registrations;
114 return $sreg->{$moniker} if exists $sreg->{$moniker};
116 # if we got here, they probably passed a full class name
117 my $mapped = $self->class_mappings->{$moniker};
118 $self->throw_exception("Can't find source for ${moniker}")
119 unless $mapped && exists $sreg->{$mapped};
120 return $sreg->{$mapped};
125 my @source_monikers = $schema->sources;
127 Returns the source monikers of all source registrations on this schema
131 sub sources { return keys %{shift->source_registrations}; }
135 my $rs = $schema->resultset('Foo');
137 Returns the resultset for the registered moniker
142 my ($self, $moniker) = @_;
143 return $self->source($moniker)->resultset;
146 =head2 load_classes [<classes>, (<class>, <class>), {<namespace> => [<classes>]}]
148 Uses L<Module::Find> to find all classes under the database class' namespace,
149 or uses the classes you select. Then it loads the component (using L<use>),
150 and registers them (using B<register_class>);
152 It is possible to comment out classes with a leading '#', but note that perl
153 will think it's a mistake (trying to use a comment in a qw list) so you'll
154 need to add "no warnings 'qw';" before your load_classes call.
159 my ($class, @params) = @_;
164 foreach my $param (@params) {
165 if (ref $param eq 'ARRAY') {
166 # filter out commented entries
167 my @modules = grep { $_ !~ /^#/ } @$param;
169 push (@{$comps_for{$class}}, @modules);
171 elsif (ref $param eq 'HASH') {
172 # more than one namespace possible
173 for my $comp ( keys %$param ) {
174 # filter out commented entries
175 my @modules = grep { $_ !~ /^#/ } @{$param->{$comp}};
177 push (@{$comps_for{$comp}}, @modules);
181 # filter out commented entries
182 push (@{$comps_for{$class}}, $param) if $param !~ /^#/;
186 eval "require Module::Find;";
187 $class->throw_exception("No arguments to load_classes and couldn't load".
188 " Module::Find ($@)") if $@;
189 my @comp = map { substr $_, length "${class}::" } Module::Find::findallmod($class);
190 $comps_for{$class} = \@comp;
193 foreach my $prefix (keys %comps_for) {
194 foreach my $comp (@{$comps_for{$prefix}||[]}) {
195 my $comp_class = "${prefix}::${comp}";
196 eval "use $comp_class"; # If it fails, assume the user fixed it
198 die $@ unless $@ =~ /Can't locate/;
200 $class->register_class($comp => $comp_class);
201 # if $class->can('result_source_instance');
206 =head2 compose_connection <target> <@db_info>
208 This is the most important method in this class. it takes a target namespace,
209 as well as dbh connection info, and creates a L<DBIx::Class::DB> class as
210 well as subclasses for each of your database classes in this namespace, using
213 It will also setup a ->class method on the target class, which lets you
214 resolve database classes based on the schema component name, for example
216 MyApp::DB->class('Foo') # returns MyApp::DB::Foo,
217 # which ISA MyApp::Schema::Foo
219 This is the recommended API for accessing Schema generated classes, and
220 using it might give you instant advantages with future versions of DBIC.
222 WARNING: Loading components into Schema classes after compose_connection
223 may not cause them to be seen by the classes in your target namespace due
224 to the dispatch table approach used by Class::C3. If you do this you may find
225 you need to call Class::C3->reinitialize() afterwards to get the behaviour
230 sub compose_connection {
231 my ($self, $target, @info) = @_;
232 my $base = 'DBIx::Class::ResultSetProxy';
235 if ($self eq $target) {
236 # Pathological case, largely caused by the docs on early C::M::DBIC::Plain
237 foreach my $moniker ($self->sources) {
238 my $source = $self->source($moniker);
239 my $class = $source->result_class;
240 $self->inject_base($class, $base);
241 $class->mk_classdata(resultset_instance => $source->resultset);
242 $class->mk_classdata(class_resolver => $self);
244 $self->connection(@info);
248 my $schema = $self->compose_namespace($target, $base);
249 $schema->connection(@info);
250 foreach my $moniker ($schema->sources) {
251 my $source = $schema->source($moniker);
252 my $class = $source->result_class;
253 #warn "$moniker $class $source ".$source->storage;
254 $class->mk_classdata(result_source_instance => $source);
255 $class->mk_classdata(resultset_instance => $source->resultset);
256 $class->mk_classdata(class_resolver => $schema);
261 sub compose_namespace {
262 my ($self, $target, $base) = @_;
263 my %reg = %{ $self->source_registrations };
266 my $schema = $self->clone;
267 foreach my $moniker ($schema->sources) {
268 my $source = $schema->source($moniker);
269 my $target_class = "${target}::${moniker}";
271 $target_class => $source->result_class, ($base ? $base : ())
273 $source->result_class($target_class);
277 *{"${target}::schema"} =
279 foreach my $meth (qw/class source resultset/) {
280 *{"${target}::${meth}"} =
281 sub { shift->schema->$meth(@_) };
287 =head2 setup_connection_class <$target> <@info>
289 Sets up a database connection class to inject between the schema
290 and the subclasses the schema creates.
294 sub setup_connection_class {
295 my ($class, $target, @info) = @_;
296 $class->inject_base($target => 'DBIx::Class::DB');
297 #$target->load_components('DB');
298 $target->connection(@info);
301 =head2 connection(@args)
303 Instantiates a new Storage object of type storage_type and passes the
304 arguments to $storage->connect_info. Sets the connection in-place on
310 my ($self, @info) = @_;
311 my $storage_class = $self->storage_type;
312 $storage_class = 'DBIx::Class::Storage'.$storage_class
313 if $storage_class =~ m/^::/;
314 $storage_class->require;
315 my $storage = $storage_class->new;
316 $storage->connect_info(\@info);
317 $self->storage($storage);
321 =head2 connect(@info)
323 Conveneience method, equivalent to $schema->clone->connection(@info)
327 sub connect { shift->clone->connection(@_) };
331 Clones the schema and its associated result_source objects and returns the
338 my $clone = bless({ (ref $self ? %$self : ()) }, ref $self || $self);
339 foreach my $moniker ($self->sources) {
340 my $source = $self->source($moniker);
341 my $new = $source->new($source);
342 $clone->register_source($moniker => $new);
347 =item populate($moniker, \@data);
349 Populates the source registered with the given moniker with the supplied data.
350 @data should be a list of listrefs, the first containing column names, the
351 second matching values - i.e.
353 $schema->populate('Foo', [
354 [ qw/foo_id foo_string/ ],
363 my ($self, $name, $data) = @_;
364 my $rs = $self->resultset($name);
365 my @names = @{shift(@$data)};
366 foreach my $item (@$data) {
368 @create{@names} = @$item;
369 $rs->create(\%create);
373 =item throw_exception
375 Defaults to using Carp::Clan to report errors from user perspective.
379 sub throw_exception {
388 Matt S. Trout <mst@shadowcatsystems.co.uk>
392 You may distribute this code under the same terms as Perl itself.