Moving towards instance-based schemas

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Schema.pm

diff --git a/lib/DBIx/Class/Schema.pm b/lib/DBIx/Class/Schema.pm
index 85c2db6..502ec55 100644 (file)
--- a/lib/DBIx/Class/Schema.pm
+++ b/lib/DBIx/Class/Schema.pm
@@ -8,6 +8,8 @@ use base qw/DBIx::Class/;
 
 __PACKAGE__->load_components(qw/Exception/);
 __PACKAGE__->mk_classdata('class_registrations' => {});
+__PACKAGE__->mk_classdata('storage_type' => 'DBI');
+__PACKAGE__->mk_classdata('storage');
 
 =head1 NAME
 
@@ -29,7 +31,7 @@ in My/Schema/Foo.pm
 
   use base qw/DBIx::Class/;
 
-  __PACKAGE__->load_components(qw/Core PK::Auto::Pg/); # for example
+  __PACKAGE__->load_components(qw/PK::Auto::Pg Core/); # for example
   __PACKAGE__->table('foo');
   ...
 
@@ -56,9 +58,7 @@ particular which module inherits off which.
 
 =head1 METHODS
 
-=over 4
-
-=item register_class <component> <component_class>
+=head2 register_class <component> <component_class>
 
 Registers the class in the schema's class_registrations. This is a hash
 containing database classes, keyed by their monikers. It's used by
@@ -73,7 +73,7 @@ sub register_class {
   $class->class_registrations(\%reg);
 }
 
-=item registered_classes
+=head2 registered_classes
 
 Simple read-only accessor for the schema's registered classes. See 
 register_class above if you want to modify it.
@@ -85,7 +85,20 @@ sub registered_classes {
   return values %{shift->class_registrations};
 }
 
-=item  load_classes [<classes>, (<class>, <class>), {<namespace> => [<classes>]}]
+=head2 class
+
+  my $class = $schema->class('Foo');
+
+Shortcut to retrieve a single class by its registered name
+
+=cut
+
+sub class {
+  my ($self, $class) = @_;
+  return $self->class_registrations->{$class};
+}
+
+=head2  load_classes [<classes>, (<class>, <class>), {<namespace> => [<classes>]}]
 
 Uses L<Module::Find> to find all classes under the database class' namespace,
 or uses the classes you select.  Then it loads the component (using L<use>), 
@@ -135,57 +148,79 @@ sub load_classes {
   foreach my $prefix (keys %comps_for) {
     foreach my $comp (@{$comps_for{$prefix}||[]}) {
       my $comp_class = "${prefix}::${comp}";
-      print "$comp_class\n";
       eval "use $comp_class"; # If it fails, assume the user fixed it
+      if ($@) {
+        die $@ unless $@ =~ /Can't locate/;
+      }
       $class->register_class($comp => $comp_class);
     }
   }
 }
 
-=item compose_connection <target> <@db_info>
+=head2 compose_connection <target> <@db_info>
 
 This is the most important method in this class. it takes a target namespace,
 as well as dbh connection info, and creates a L<DBIx::Class::DB> class as
 well as subclasses for each of your database classes in this namespace, using
 this connection.
 
-It will also setup a ->table method on the target class, which lets you
+It will also setup a ->class method on the target class, which lets you
 resolve database classes based on the schema component name, for example
 
-  MyApp::DB->table('Foo') # returns MyApp::DB::Foo, 
+  MyApp::DB->class('Foo') # returns MyApp::DB::Foo, 
                           # which ISA MyApp::Schema::Foo
 
 This is the recommended API for accessing Schema generated classes, and 
 using it might give you instant advantages with future versions of DBIC.
 
+WARNING: Loading components into Schema classes after compose_connection
+may not cause them to be seen by the classes in your target namespace due
+to the dispatch table approach used by Class::C3. If you do this you may find
+you need to call Class::C3->reinitialize() afterwards to get the behaviour
+you expect.
+
 =cut
 
 sub compose_connection {
   my ($class, $target, @info) = @_;
   my $conn_class = "${target}::_db";
   $class->setup_connection_class($conn_class, @info);
+  my $schema = $class->compose_namespace($target, $conn_class);
+  $schema->storage($conn_class->storage);
+  foreach my $class ($schema->registered_classes) {
+    my $source = $class->result_source;
+    $source = $source->new($source);
+    $source->schema($schema);
+    $source->result_class($class);
+    $class->mk_classdata(result_source => $source);
+  }
+  return $schema;
+}
+
+sub compose_namespace {
+  my ($class, $target, $base) = @_;
   my %reg = %{ $class->class_registrations };
   my %target;
   my %map;
+  my $schema = bless({ }, $class);
   while (my ($comp, $comp_class) = each %reg) {
     my $target_class = "${target}::${comp}";
-    $class->inject_base($target_class, $comp_class, $conn_class);
-    $target_class->table($comp_class->table);
+    $class->inject_base($target_class, $comp_class, $base);
     @map{$comp, $comp_class} = ($target_class, $target_class);
   }
+  $schema->class_registrations(\%map);
   {
     no strict 'refs';
+    *{"${target}::schema"} =
+      sub { $schema };
     *{"${target}::class"} =
-      sub {
-        my ($class, $to_map) = @_;
-        return $map{$to_map};
-      };
-    *{"${target}::classes"} = sub { return \%map; };
+      sub { shift->schema->class(@_) };
   }
-  $conn_class->class_resolver($target);
+  $base->class_resolver($target);
+  return $schema;
 }
 
-=item setup_connection_class <$target> <@info>
+=head2 setup_connection_class <$target> <@info>
 
 Sets up a database connection class to inject between the schema
 and the subclasses the schema creates.
@@ -201,8 +236,6 @@ sub setup_connection_class {
 
 1;
 
-=back
-
 =head1 AUTHORS
 
 Matt S. Trout <mst@shadowcatsystems.co.uk>