Following the example in the cookbook[1], I moved components into a base result class, only to discover that cascaded deletion no longer worked. Apparently, load_components sets the MRO to C3, which DBIx::Class relies on heavily. Moving those calls out of the individual result classes caused them to revert to perl's default DFS MRO. Since InflateColumn is a subclass of DBIx::Class::Row, Row's delete method appears before CascadeActions wrapper under DFS. An example script is below.
Is there any way to set the MRO for all loaded classes so that a base class, or even DBIx::Class itself, could handle this transparently, or do all classes need to individually ensure that they use C3? [1]: https://metacpan.org/pod/distribution/DBIx-Class/lib/DBIx/Class/Manual/Cookbook.pod#Move-Common-Startup-into-a-Base-Class ## broken cascade example package Test::Schema::Result; use base 'DBIx::Class::Core'; ## loads DBIx::Class::Row, putting it above ## DBIx::Class::Relationship::CascadeActions for default DFS MRO __PACKAGE__->load_components('InflateColumn::DateTime'); package Test::Schema::Result::Bar; use base 'Test::Schema::Result'; ## uncommenting either of these set C3 MRO, putting CascadeActions before Row #use mro 'c3'; #__PACKAGE__->load_components('InflateColumn::DateTime'); __PACKAGE__->table('Bar'); __PACKAGE__->add_columns( id => { data_type => 'integer', is_numeric => 1 } ); __PACKAGE__->set_primary_key('id'); __PACKAGE__->has_many( foo => 'Test::Schema::Result::Foo' => 'bar_id' ); package Test::Schema::Result::Foo; use base 'Test::Schema::Result'; __PACKAGE__->table('foo'); __PACKAGE__->add_columns( id => { data_type => 'integer', is_numeric => 1 }, bar_id => { data_type => 'integer', is_numeric => 1 }, ); __PACKAGE__->set_primary_key('id'); __PACKAGE__->belongs_to( bar => 'Test::Schema::Result::Bar' => 'id' ); package Test::Schema; use base 'DBIx::Class::Schema'; __PACKAGE__->register_class( Bar => 'Test::Schema::Result::Bar' ); __PACKAGE__->register_class( Foo => 'Test::Schema::Result::Foo' ); package main; use Test::More; my $schema = Test::Schema->connect('dbi:SQLite:dbname=:memory:'); $schema->deploy; my ( $bar_rs, $foo_rs ) = ( $schema->resultset('Bar'), $schema->resultset('Foo') ); $bar_rs->create( { id => 1 } ); $foo_rs->create( { id => 1, bar_id => 1 } ); is( $bar_rs->count, 1 ); is( $foo_rs->count, 1 ); $bar_rs->find(1)->delete; # should cascade to delete foo as well is( $bar_rs->count, 0 ); is( $foo_rs->count, 0 ); _______________________________________________ List: http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/dbix-class IRC: irc.perl.org#dbix-class SVN: http://dev.catalyst.perl.org/repos/bast/DBIx-Class/ Searchable Archive: http://www.grokbase.com/group/dbix-class@lists.scsys.co.uk
