X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship.pm;h=22be1d319ca9b70a7780e45c297f8f5c3d091ff0;hb=9b465d002d544e25ae5756304c4ea59577aca363;hp=1106f28c8caecc3d392c4ee07c63066c8fbd5394;hpb=78bab9cad621ac5e3d1d12b02c41d662dec7a22a;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Relationship.pm b/lib/DBIx/Class/Relationship.pm
index 1106f28..22be1d3 100644
--- a/lib/DBIx/Class/Relationship.pm
+++ b/lib/DBIx/Class/Relationship.pm
@@ -3,9 +3,15 @@ package DBIx::Class::Relationship;
 use strict;
 use warnings;
 
-use base qw/Class::Data::Inheritable/;
+use base qw/DBIx::Class/;
 
-__PACKAGE__->mk_classdata('_relationships', { } );
+__PACKAGE__->load_own_components(qw/
+  Helpers
+  Accessor
+  CascadeActions
+  ProxyMethods
+  Base
+/);
 
 =head1 NAME 
 
@@ -16,118 +22,97 @@ DBIx::Class::Relationship - Inter-table relationships
 =head1 DESCRIPTION
 
 This class handles relationships between the tables in your database
-model. It allows your to set up relationships, and to perform joins
-on searches.
+model. It allows you to set up relationships and perform joins on them.
+
+Only the helper methods for setting up standard relationship types
+are documented here. For the basic, lower-level methods, see
+L<DBIx::Class::Relationship::Base>.
 
 =head1 METHODS
 
-=over 4
+All helper methods take the following arguments:
 
-=cut
+  __PACKAGE__>$method_name('relname', 'Foreign::Class', $cond, $attrs);
+  
+Both C<$cond> and C<$attrs> are optional. Pass C<undef> for C<$cond> if
+you want to use the default value for it, but still want to set C<$attrs>.
+See L<DBIx::Class::Relationship::Base> for a list of valid attributes.
 
-sub add_relationship {
-  my ($class, $rel, $f_class, $cond, $attrs) = @_;
-  my %rels = %{ $class->_relationships };
-  $rels{$rel} = { class => $f_class,
-                  cond  => $cond,
-                  attrs => $attrs };
-  $class->_relationships(\%rels);
-}
-
-sub _cond_key {
-  my ($self, $attrs, $key) = @_;
-  my $action = $attrs->{_action} || '';
-  if ($action eq 'convert') {
-    unless ($key =~ s/^foreign\.//) {
-      $self->throw("Unable to convert relationship to WHERE clause: invalid key ${key}");
-    }
-    return $key;
-  } elsif ($action eq 'join') {
-    my ($type, $field) = split(/\./, $key);
-    if ($attrs->{_aliases}{$type}) {
-      return join('.', $attrs->{_aliases}{$type}, $field);
-    } else {
-      $self->throw( "Unable to resolve type ${type}: only have aliases for ".
-            join(', ', keys %{$attrs->{_aliases}{$type} || {}}) );
-    }
-  }
-  return $self->NEXT::ACTUAL::_cond_key($attrs, $key);
-}
-
-sub _cond_value {
-  my ($self, $attrs, $key, $value) = @_;
-  my $action = $attrs->{_action} || '';
-  if ($action eq 'convert') {
-    unless ($value =~ s/^self\.//) {
-      $self->throw( "Unable to convert relationship to WHERE clause: invalid value ${value}" );
-    }
-    unless ($self->_columns->{$value}) {
-      $self->throw( "Unable to convert relationship to WHERE clause: no such accessor ${value}" );
-    }
-    push(@{$attrs->{bind}}, $self->get_column($value));
-    return '?';
-  } elsif ($action eq 'join') {
-    my ($type, $field) = split(/\./, $value);
-    if ($attrs->{_aliases}{$type}) {
-      return join('.', $attrs->{_aliases}{$type}, $field);
-    } else {
-      $self->throw( "Unable to resolve type ${type}: only have aliases for ".
-            join(', ', keys %{$attrs->{_aliases}{$type} || {}}) );
-    }
-  }
-      
-  return $self->NEXT::ACTUAL::_cond_value($attrs, $key, $value)
-}
-
-sub search_related {
-  my $self = shift;
-  my $rel = shift;
-  my $attrs = { };
-  if (@_ > 1 && ref $_[$#_] eq 'HASH') {
-    $attrs = { %{ pop(@_) } };
-  }
-  my $rel_obj = $self->_relationships->{$rel};
-  $self->throw( "No such relationship ${rel}" ) unless $rel;
-  $attrs = { %{$rel_obj->{attrs} || {}}, %{$attrs || {}} };
-  my $s_cond;
-  if (@_) {
-    $self->throw( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1));
-    my $query = ((@_ > 1) ? {@_} : shift);
-    $s_cond = $self->_cond_resolve($query, $attrs);
-  }
-  $attrs->{_action} = 'convert';
-  my ($cond) = $self->_cond_resolve($rel_obj->{cond}, $attrs);
-  $cond = "${s_cond} AND ${cond}" if $s_cond;
-  return $rel_obj->{class}->retrieve_from_sql($cond, @{$attrs->{bind} || []},
-                                                $attrs);
-}
-
-sub create_related {
-  my ($self, $rel, $values, $attrs) = @_;
-  $self->throw( "Can't call create_related as class method" ) 
-    unless ref $self;
-  $self->throw( "create_related needs a hash" ) 
-    unless (ref $values eq 'HASH');
-  my $rel_obj = $self->_relationships->{$rel};
-  $self->throw( "No such relationship ${rel}" ) unless $rel;
-  $self->throw( "Can't abstract implicit create for ${rel}, condition not a hash" )
-    unless ref $rel_obj->{cond} eq 'HASH';
-  $attrs = { %{$rel_obj->{attrs}}, %{$attrs || {}}, _action => 'convert' };
-  my %fields = %$values;
-  while (my ($k, $v) = each %{$rel_obj->{cond}}) {
-    $self->_cond_value($attrs, $k => $v);
-    $fields{$self->_cond_key($attrs, $k)} = (@{delete $attrs->{bind}})[0];
-  }
-  return $rel_obj->{class}->create(\%fields);
-}
+=head2 belongs_to
 
-1;
+  # in a Bar class (where Foo has many Bars)
+  __PACKAGE__->belongs_to(foo => Foo);
+  my $f_obj = $obj->foo;
+  $obj->foo($new_f_obj);
+
+Creates a relationship where the calling class stores the foreign class's 
+primary key in one (or more) of its columns. If $cond is a column name
+instead of a join condition hash, that is used as the name of the column
+holding the foreign key. If $cond is not given, the relname is used as
+the column name.
+
+NOTE: If you are used to L<Class::DBI> relationships, this is the equivalent
+of C<has_a>.
+
+=head2 has_many
+
+  # in a Foo class (where Foo has many Bars)
+  __PACKAGE__->has_many(bar => Bar, 'foo');
+  my $f_resultset = $obj->foo;
+  my $f_resultset = $obj->foo({ name => { LIKE => '%macaroni%' }, { prefetch => [qw/bar/] });
+  my @f_obj = $obj->foo;
+
+  $obj->add_to_foo(\%col_data);
+
+Creates a one-to-many relationship, where the corresponding elements of the
+foreign class store the calling class's primary key in one (or more) of its
+columns. You should pass the name of the column in the foreign class as the
+$cond argument, or specify a complete join condition.
+
+If you delete an object in a class with a C<has_many> relationship, all
+related objects will be deleted as well. However, any database-level
+cascade or restrict will take precedence.
+
+=head2 might_have
+
+  __PACKAGE__->might_have(baz => Baz);
+  my $f_obj = $obj->baz; # to get the baz object
 
-=back
+Creates an optional one-to-one relationship with a class, where the foreign class 
+stores our primary key in one of its columns. Defaults to the primary key of the
+foreign class unless $cond specifies a column or join condition.
+
+If you update or delete an object in a class with a C<might_have> relationship, 
+the related object will be updated or deleted as well. Any database-level update
+or delete constraints will override this behavior.
+
+=head2 has_one
+
+  __PACKAGE__->has_one(gorch => Gorch);
+  my $f_obj = $obj->gorch;
+
+Creates a one-to-one relationship with another class. This is just like C<might_have>,
+except the implication is that the other object is always present. The only different
+between C<has_one> and C<might_have> is that C<has_one> uses an (ordinary) inner join,
+whereas C<might_have> uses a left join.
+
+
+=head2 many_to_many
+
+  __PACKAGE__->many_to_many( 'accessorname' => 'a_to_b', 'table_b' );
+  my @f_objs = $obj_a->accessorname;
+
+Creates an accessor bridging two relationships; not strictly a relationship
+in its own right, although the accessor will return a resultset or collection
+of objects just as a has_many would.
+
+=cut
+
+1;
 
 =head1 AUTHORS
 
-Matt S. Trout <perl-stuff@trout.me.uk>
+Matt S. Trout <mst@shadowcatsystems.co.uk>
 
 =head1 LICENSE