X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship%2FBase.pm;h=b193aa06e308a2a6a97f93f82c6dd605d774dd41;hb=8a71e6ae9971f5582a85712d0e64fb865cc4581d;hp=4fb98bc6fe5c179ea68a4019fe7aea9dd8423055;hpb=30236e4788db222d813d881c71269e500b3f8385;p=dbsrgits%2FDBIx-Class-Historic.git

diff --git a/lib/DBIx/Class/Relationship/Base.pm b/lib/DBIx/Class/Relationship/Base.pm
index 4fb98bc..b193aa0 100644
--- a/lib/DBIx/Class/Relationship/Base.pm
+++ b/lib/DBIx/Class/Relationship/Base.pm
@@ -5,9 +5,7 @@ use warnings;
 
 use base qw/DBIx::Class/;
 
-__PACKAGE__->mk_classdata('_relationships', { } );
-
-=head1 NAME 
+=head1 NAME
 
 DBIx::Class::Relationship::Base - Inter-table relationships
 
@@ -17,37 +15,56 @@ DBIx::Class::Relationship::Base - Inter-table relationships
 
 This class provides methods to describe the relationships between the
 tables in your database model. These are the "bare bones" relationships
-methods, for predefined ones, look in L<DBIx::Class::Relationship>. 
+methods, for predefined ones, look in L<DBIx::Class::Relationship>.
 
 =head1 METHODS
 
 =head2 add_relationship
 
-=head3 Arguments: ('relname', 'Foreign::Class', $cond, $attrs)
+=over 4
+
+=item Arguments: 'relname', 'Foreign::Class', $cond, $attrs
+
+=back
 
   __PACKAGE__->add_relationship('relname', 'Foreign::Class', $cond, $attrs);
 
-The condition needs to be an SQL::Abstract-style representation of the
-join between the tables. When resolving the condition for use in a JOIN,
-keys using the psuedo-table I<foreign> are resolved to mean "the Table on the
-other side of the relationship", and values using the psuedo-table I<self>
+The condition needs to be an L<SQL::Abstract>-style representation of the
+join between the tables. When resolving the condition for use in a C<JOIN>,
+keys using the pseudo-table C<foreign> are resolved to mean "the Table on the
+other side of the relationship", and values using the pseudo-table C<self>
 are resolved to mean "the Table this class is representing". Other
 restrictions, such as by value, sub-select and other tables, may also be
-used. Please check your database for JOIN parameter support.
+used. Please check your database for C<JOIN> parameter support.
 
-For example, if you're creating a rel from Author to Book, where the Book
-table has a column author_id containing the ID of the Author row:
+For example, if you're creating a relationship from C<Author> to C<Book>, where
+the C<Book> table has a column C<author_id> containing the ID of the C<Author>
+row:
 
   { 'foreign.author_id' => 'self.id' }
 
-will result in the JOIN clause
+will result in the C<JOIN> clause
 
-  author me JOIN book book ON bar.author_id = me.id
+  author me JOIN book book ON book.author_id = me.id
 
-You can specify as many foreign => self mappings as necessary. Each key/value
-pair provided in a hashref will be used as ANDed conditions, to add an ORed
-condition, use an arrayref of hashrefs. See the L<SQL::Abstract> documentation
-for more details.
+For multi-column foreign keys, you will need to specify a C<foreign>-to-C<self>
+mapping for each column in the key. For example, if you're creating a
+relationship from C<Book> to C<Edition>, where the C<Edition> table refers to a
+publisher and a type (e.g. "paperback"):
+
+  {
+    'foreign.publisher_id' => 'self.publisher_id',
+    'foreign.type_id'      => 'self.type_id',
+  }
+
+This will result in the C<JOIN> clause:
+
+  book me JOIN edition edition ON edition.publisher_id = me.publisher_id
+    AND edition.type_id = me.type_id
+
+Each key-value pair provided in a hashref will be used as C<AND>ed conditions.
+To add an C<OR>ed condition, use an arrayref of hashrefs. See the
+L<SQL::Abstract> documentation for more details.
 
 Valid attributes are as follows:
 
@@ -64,9 +81,10 @@ command immediately before C<JOIN>.
 An arrayref containing a list of accessors in the foreign class to create in
 the main class. If, for example, you do the following:
   
-  MyDB::Schema::CD->might_have(liner_notes => 'MyDB::Schema::LinerNotes', undef, {
-    proxy => [ qw/notes/ ],
-  });
+  MyDB::Schema::CD->might_have(liner_notes => 'MyDB::Schema::LinerNotes',
+    undef, {
+      proxy => [ qw/notes/ ],
+    });
   
 Then, assuming MyDB::Schema::LinerNotes has an accessor named notes, you can do:
 
@@ -87,38 +105,56 @@ created, which calls C<create_related> for the relationship.
 
 =head2 register_relationship
 
-=head3 Arguments: ($relname, $rel_info)
+=over 4
+
+=item Arguments: $relname, $rel_info
+
+=back
 
 Registers a relationship on the class. This is called internally by
-L<DBIx::Class::ResultSourceProxy> to set up Accessors and Proxies.
+DBIx::Class::ResultSourceProxy to set up Accessors and Proxies.
 
 =cut
 
 sub register_relationship { }
 
-=head2 related_resultset($name)
+=head2 related_resultset
+
+=over 4
+
+=item Arguments: $relationship_name
+
+=item Return Value: $related_resultset
+
+=back
 
-  $rs = $obj->related_resultset('related_table');
+  $rs = $cd->related_resultset('artist');
 
-Returns a L<DBIx::Class::ResultSet> for the relationship named $name.
+Returns a L<DBIx::Class::ResultSet> for the relationship named
+$relationship_name.
 
 =cut
 
 sub related_resultset {
   my $self = shift;
-  $self->throw_exception("Can't call *_related as class methods") unless ref $self;
+  $self->throw_exception("Can't call *_related as class methods")
+    unless ref $self;
   my $rel = shift;
   my $rel_obj = $self->relationship_info($rel);
-  $self->throw_exception( "No such relationship ${rel}" ) unless $rel_obj;
+  $self->throw_exception( "No such relationship ${rel}" )
+    unless $rel_obj;
   
   return $self->{related_resultsets}{$rel} ||= do {
     my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
     $attrs = { %{$rel_obj->{attrs} || {}}, %$attrs };
 
-    $self->throw_exception( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1));
+    $self->throw_exception( "Invalid query: @_" )
+      if (@_ > 1 && (@_ % 2 == 1));
     my $query = ((@_ > 1) ? {@_} : shift);
 
-    my $cond = $self->result_source->resolve_condition($rel_obj->{cond}, $rel, $self);
+    my $cond = $self->result_source->resolve_condition(
+      $rel_obj->{cond}, $rel, $self
+    );
     if (ref $cond eq 'ARRAY') {
       $cond = [ map { my $hash;
         foreach my $key (keys %$_) {
@@ -131,7 +167,9 @@ sub related_resultset {
       }
     }
     $query = ($query ? { '-and' => [ $cond, $query ] } : $cond);
-    $self->result_source->related_source($rel)->resultset->search($query, $attrs);
+    $self->result_source->related_source($rel)->resultset->search(
+      $query, $attrs
+    );
   };
 }
 
@@ -153,8 +191,10 @@ sub search_related {
 
   $obj->count_related('relname', $cond, $attrs);
 
-Returns the count of all the items in the related resultset, restricted by
-the current item or where conditions. Can be called on a L<DBIx::Classl::Manual::Glossary/"ResultSet"> or a L<DBIx::Class::Manual::Glossary/"Row"> object.
+Returns the count of all the items in the related resultset, restricted by the
+current item or where conditions. Can be called on a
+L<DBIx::Class::Manual::Glossary/"ResultSet"> or a
+L<DBIx::Class::Manual::Glossary/"Row"> object.
 
 =cut
 
@@ -168,9 +208,9 @@ sub count_related {
   my $new_obj = $obj->new_related('relname', \%col_data);
 
 Create a new item of the related foreign class. If called on a
-L<DBIx::Class::Manual::Glossary/"Row"> object, it will magically
-set any primary key values into foreign key columns for you. The newly
-created item will not be saved into your storage until you call C<insert>
+L<DBIx::Class::Manual::Glossary/"Row"> object, it will magically set any
+primary key values into foreign key columns for you. The newly created item
+will not be saved into your storage until you call L<DBIx::Class::Row/insert>
 on it.
 
 =cut
@@ -203,7 +243,7 @@ sub create_related {
   my $found_item = $obj->find_related('relname', @pri_vals | \%pri_vals);
 
 Attempt to find a related object using its primary key or unique constraints.
-See C<find> in L<DBIx::Class::ResultSet> for details.
+See L<DBIx::Class::ResultSet/find> for details.
 
 =cut
 
@@ -213,12 +253,27 @@ sub find_related {
   return $self->search_related($rel)->find(@_);
 }
 
+=head2 find_or_new_related
+
+  my $new_obj = $obj->find_or_new_related('relname', \%col_data);
+
+Find an item of a related class. If none exists, instantiate a new item of the
+related class. The object will not be saved into your storage until you call
+L<DBIx::Class::Row/insert> on it.
+
+=cut
+
+sub find_or_new_related {
+  my $self = shift;
+  return $self->find_related(@_) || $self->new_related(@_);
+}
+
 =head2 find_or_create_related
 
   my $new_obj = $obj->find_or_create_related('relname', \%col_data);
 
-Find or create an item of a related class. See C<find_or_create> in
-L<DBIx::Class::ResultSet> for details.
+Find or create an item of a related class. See
+L<DBIx::Class::ResultSet/find_or_create> for details.
 
 =cut
 
@@ -227,6 +282,21 @@ sub find_or_create_related {
   return $self->find_related(@_) || $self->create_related(@_);
 }
 
+=head2 update_or_create_related
+
+  my $updated_item = $obj->update_or_create_related('relname', \%col_data, \%attrs?);
+
+Update or create an item of a related class. See
+L<DBIx::Class::ResultSet/update_or_create> for details.
+
+=cut
+
+sub update_or_create_related {
+  my $self = shift;
+  my $rel = shift;
+  return $self->related_resultset($rel)->update_or_create(@_);
+}
+
 =head2 set_from_related
 
   $book->set_from_related('author', $author_obj);
@@ -236,8 +306,8 @@ related object. This is used to associate previously separate objects, for
 example, to set the correct author for a book, find the Author object, then
 call set_from_related on the book.
 
-The columns are only set in the local copy of the object, call C<update> to set
-them in the storage.
+The columns are only set in the local copy of the object, call L</update> to
+set them in the storage.
 
 =cut
 
@@ -246,12 +316,16 @@ sub set_from_related {
   my $rel_obj = $self->relationship_info($rel);
   $self->throw_exception( "No such relationship ${rel}" ) unless $rel_obj;
   my $cond = $rel_obj->{cond};
-  $self->throw_exception( "set_from_related can only handle a hash condition; the "
-    ."condition for $rel is of type ".(ref $cond ? ref $cond : 'plain scalar'))
-      unless ref $cond eq 'HASH';
-  my $f_class = $self->result_source->schema->class($rel_obj->{class});
-  $self->throw_exception( "Object $f_obj isn't a ".$f_class )
-    unless $f_obj->isa($f_class);
+  $self->throw_exception(
+    "set_from_related can only handle a hash condition; the ".
+    "condition for $rel is of type ".
+    (ref $cond ? ref $cond : 'plain scalar')
+  ) unless ref $cond eq 'HASH';
+  if (defined $f_obj) {
+    my $f_class = $self->result_source->schema->class($rel_obj->{class});
+    $self->throw_exception( "Object $f_obj isn't a ".$f_class )
+      unless $f_obj->isa($f_class);
+  }
   $self->set_columns(
     $self->result_source->resolve_condition(
        $rel_obj->{cond}, $f_obj, $rel));
@@ -262,8 +336,8 @@ sub set_from_related {
 
   $book->update_from_related('author', $author_obj);
 
-As C<set_from_related>, but the changes are immediately updated onto your
-storage.
+The same as L</"set_from_related">, but the changes are immediately updated
+in storage.
 
 =cut