1 package DBIx::Class::Schema;
6 use Carp::Clan qw/^DBIx::Class/;
8 use base qw/DBIx::Class/;
10 __PACKAGE__->mk_classdata('class_mappings' => {});
11 __PACKAGE__->mk_classdata('source_registrations' => {});
12 __PACKAGE__->mk_classdata('storage_type' => '::DBI');
13 __PACKAGE__->mk_classdata('storage');
17 DBIx::Class::Schema - composable schemas
22 use base qw/DBIx::Class::Schema/;
24 # load My::Schema::Foo, My::Schema::Bar, My::Schema::Baz
25 __PACKAGE__->load_classes(qw/Foo Bar Baz/);
27 package My::Schema::Foo;
28 use base qw/DBIx::Class/;
29 __PACKAGE__->load_components(qw/PK::Auto::Pg Core/); # for example
30 __PACKAGE__->table('foo');
32 # Elsewhere in your code:
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';
233 eval "require ${base};";
234 $self->throw_exception("No arguments to load_classes and couldn't load".
235 " ${base} ($@)") if $@;
237 if ($self eq $target) {
238 # Pathological case, largely caused by the docs on early C::M::DBIC::Plain
239 foreach my $moniker ($self->sources) {
240 my $source = $self->source($moniker);
241 my $class = $source->result_class;
242 $self->inject_base($class, $base);
243 $class->mk_classdata(resultset_instance => $source->resultset);
244 $class->mk_classdata(class_resolver => $self);
246 $self->connection(@info);
250 my $schema = $self->compose_namespace($target, $base);
253 *{"${target}::schema"} = sub { $schema };
256 $schema->connection(@info);
257 foreach my $moniker ($schema->sources) {
258 my $source = $schema->source($moniker);
259 my $class = $source->result_class;
260 #warn "$moniker $class $source ".$source->storage;
261 $class->mk_classdata(result_source_instance => $source);
262 $class->mk_classdata(resultset_instance => $source->resultset);
263 $class->mk_classdata(class_resolver => $schema);
268 sub compose_namespace {
269 my ($self, $target, $base) = @_;
270 my %reg = %{ $self->source_registrations };
273 my $schema = $self->clone;
274 foreach my $moniker ($schema->sources) {
275 my $source = $schema->source($moniker);
276 my $target_class = "${target}::${moniker}";
278 $target_class => $source->result_class, ($base ? $base : ())
280 $source->result_class($target_class);
284 foreach my $meth (qw/class source resultset/) {
285 *{"${target}::${meth}"} =
286 sub { shift->schema->$meth(@_) };
292 =head2 setup_connection_class <$target> <@info>
294 Sets up a database connection class to inject between the schema
295 and the subclasses the schema creates.
299 sub setup_connection_class {
300 my ($class, $target, @info) = @_;
301 $class->inject_base($target => 'DBIx::Class::DB');
302 #$target->load_components('DB');
303 $target->connection(@info);
306 =head2 connection(@args)
308 Instantiates a new Storage object of type storage_type and passes the
309 arguments to $storage->connect_info. Sets the connection in-place on
315 my ($self, @info) = @_;
316 my $storage_class = $self->storage_type;
317 $storage_class = 'DBIx::Class::Storage'.$storage_class
318 if $storage_class =~ m/^::/;
319 eval "require ${storage_class};";
320 $self->throw_exception("No arguments to load_classes and couldn't load".
321 " ${storage_class} ($@)") if $@;
322 my $storage = $storage_class->new;
323 $storage->connect_info(\@info);
324 $self->storage($storage);
328 =head2 connect(@info)
330 Conveneience method, equivalent to $schema->clone->connection(@info)
334 sub connect { shift->clone->connection(@_) }
338 Begins a transaction (does nothing if AutoCommit is off).
342 sub txn_begin { shift->storage->txn_begin }
346 Commits the current transaction.
350 sub txn_commit { shift->storage->txn_commit }
354 Rolls back the current transaction.
358 sub txn_rollback { shift->storage->txn_rollback }
362 Clones the schema and its associated result_source objects and returns the
369 my $clone = bless({ (ref $self ? %$self : ()) }, ref $self || $self);
370 foreach my $moniker ($self->sources) {
371 my $source = $self->source($moniker);
372 my $new = $source->new($source);
373 $clone->register_source($moniker => $new);
378 =head2 populate($moniker, \@data);
380 Populates the source registered with the given moniker with the supplied data.
381 @data should be a list of listrefs, the first containing column names, the
382 second matching values - i.e.
384 $schema->populate('Foo', [
385 [ qw/foo_id foo_string/ ],
394 my ($self, $name, $data) = @_;
395 my $rs = $self->resultset($name);
396 my @names = @{shift(@$data)};
397 foreach my $item (@$data) {
399 @create{@names} = @$item;
400 $rs->create(\%create);
404 =head2 throw_exception
406 Defaults to using Carp::Clan to report errors from user perspective.
410 sub throw_exception {
419 Matt S. Trout <mst@shadowcatsystems.co.uk>
423 You may distribute this code under the same terms as Perl itself.