1 package DBIx::Class::ResultSource;
6 use DBIx::Class::ResultSet;
10 use base qw/DBIx::Class/;
11 __PACKAGE__->load_components(qw/AccessorGroup/);
13 __PACKAGE__->mk_group_accessors('simple' =>
14 qw/_ordered_columns _columns _primaries name resultset_class result_class schema from _relationships/);
18 DBIx::Class::ResultSource - Result source object
24 A ResultSource is a component of a schema from which results can be directly
25 retrieved, most usually a table (see L<DBIx::Class::ResultSource::Table>)
32 my ($class, $attrs) = @_;
33 $class = ref $class if ref $class;
34 my $new = bless({ %{$attrs || {}} }, $class);
35 $new->{resultset_class} ||= 'DBIx::Class::ResultSet';
36 $new->{_ordered_columns} ||= [];
37 $new->{_columns} ||= {};
38 $new->{_relationships} ||= {};
39 $new->{name} ||= "!!NAME NOT SET!!";
44 my ($self, @cols) = @_;
45 $self->_ordered_columns( \@cols )
46 if !$self->_ordered_columns;
48 my $columns = $self->_columns;
49 while (my $col = shift @cols) {
51 my $column_info = ref $cols[0] ? shift : {};
52 # If next entry is { ... } use that for the column info, if not
53 # use an empty hashref
55 push(@added, $col) unless exists $columns->{$col};
57 $columns->{$col} = $column_info;
59 push @{ $self->_ordered_columns }, @added;
62 *add_column = \&add_columns;
66 $table->add_columns(qw/col1 col2 col3/);
68 $table->add_columns('col1' => \%col1_info, 'col2' => \%col2_info, ...);
70 Adds columns to the result source. If supplied key => hashref pairs uses
71 the hashref as the column_info for that column.
75 $table->add_column('col' => \%info?);
77 Convenience alias to add_columns
83 return $self->resultset_class->new($self);
88 if ($obj->has_column($col)) { ... }
90 Returns 1 if the source has a column of this name, 0 otherwise.
95 my ($self, $column) = @_;
96 return exists $self->_columns->{$column};
101 my $info = $obj->column_info($col);
103 Returns the column metadata hashref for a column.
108 my ($self, $column) = @_;
109 croak "No such column $column" unless exists $self->_columns->{$column};
110 return $self->_columns->{$column};
115 my @column_names = $obj->columns;
117 Returns all column names in the order they were declared to add_columns
122 croak "columns() is a read-only accessor, did you mean add_columns()?" if (@_ > 1);
123 return @{shift->{_ordered_columns}||[]};
126 =head2 set_primary_key(@cols)
128 Defines one or more columns as primary key for this source. Should be
129 called after C<add_columns>.
133 sub set_primary_key {
134 my ($self, @cols) = @_;
135 # check if primary key columns are valid columns
137 $self->throw("No such column $_ on table ".$self->name)
138 unless $self->has_column($_);
140 $self->_primaries(\@cols);
143 =head2 primary_columns
145 Read-only accessor which returns the list of primary keys.
149 sub primary_columns {
150 return @{shift->_primaries||[]};
155 Returns an expression of the source to be supplied to storage to specify
156 retrieval from this source; in the case of a database the required FROM clause
163 Returns the storage handle for the current schema
167 sub storage { shift->schema->storage; }
169 =head2 add_relationship
171 $source->add_relationship('relname', 'related_source', $cond, $attrs);
173 The relation name can be arbitrary, but must be unique for each relationship
174 attached to this result source. 'related_source' should be the name with
175 which the related result source was registered with the current schema
176 (for simple schemas this is usally either Some::Namespace::Foo or just Foo)
178 The condition needs to be an SQL::Abstract-style representation of the join
179 between the tables. For example, if you're creating a rel from Foo to Bar,
181 { 'foreign.foo_id' => 'self.id' }
183 will result in the JOIN clause
185 foo me JOIN bar bar ON bar.foo_id = me.id
187 You can specify as many foreign => self mappings as necessary.
189 Valid attributes are as follows:
195 Explicitly specifies the type of join to use in the relationship. Any SQL
196 join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in the SQL
197 command immediately before C<JOIN>.
201 An arrayref containing a list of accessors in the foreign class to proxy in
202 the main class. If, for example, you do the following:
204 __PACKAGE__->might_have(bar => 'Bar', undef, { proxy => qw[/ margle /] });
206 Then, assuming Bar has an accessor named margle, you can do:
208 my $obj = Foo->find(1);
209 $obj->margle(10); # set margle; Bar object is created if it doesn't exist
213 Specifies the type of accessor that should be created for the relationship.
214 Valid values are C<single> (for when there is only a single related object),
215 C<multi> (when there can be many), and C<filter> (for when there is a single
216 related object, but you also want the relationship accessor to double as
217 a column accessor). For C<multi> accessors, an add_to_* method is also
218 created, which calls C<create_related> for the relationship.
224 sub add_relationship {
225 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
226 die "Can't create relationship without join condition" unless $cond;
229 my %rels = %{ $self->_relationships };
230 $rels{$rel} = { class => $f_source_name,
231 source => $f_source_name,
234 $self->_relationships(\%rels);
238 # XXX disabled. doesn't work properly currently. skip in tests.
240 my $f_source = $self->schema->source($f_source_name);
242 eval "require $f_source_name;";
244 die $@ unless $@ =~ /Can't locate/;
246 $f_source = $f_source_name->result_source;
247 #my $s_class = ref($self->schema);
248 #$f_source_name =~ m/^${s_class}::(.*)$/;
249 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
250 #$f_source = $self->schema->source($f_source_name);
252 return unless $f_source; # Can't test rel without f_source
254 eval { $self->resolve_join($rel, 'me') };
256 if ($@) { # If the resolve failed, back out and re-throw the error
257 delete $rels{$rel}; #
258 $self->_relationships(\%rels);
259 die "Error creating relationship $rel: $@";
264 =head2 relationships()
266 Returns all valid relationship names for this source
271 return keys %{shift->_relationships};
274 =head2 relationship_info($relname)
276 Returns the relationship information for the specified relationship name
280 sub relationship_info {
281 my ($self, $rel) = @_;
282 return $self->_relationships->{$rel};
285 =head2 has_relationship($rel)
287 Returns 1 if the source has a relationship of this name, 0 otherwise.
291 sub has_relationship {
292 my ($self, $rel) = @_;
293 return exists $self->_relationships->{$rel};
296 =head2 resolve_join($relation)
298 Returns the join structure required for the related result source
303 my ($self, $join, $alias) = @_;
304 if (ref $join eq 'ARRAY') {
305 return map { $self->resolve_join($_, $alias) } @$join;
306 } elsif (ref $join eq 'HASH') {
307 return map { $self->resolve_join($_, $alias),
308 $self->related_source($_)->resolve_join($join->{$_}, $_) }
310 } elsif (ref $join) {
311 die("No idea how to resolve join reftype ".ref $join);
313 my $rel_info = $self->relationship_info($join);
314 die("No such relationship ${join}") unless $rel_info;
315 my $type = $rel_info->{attrs}{join_type} || '';
316 return [ { $join => $self->related_source($join)->from,
317 -join_type => $type },
318 $self->resolve_condition($rel_info->{cond}, $join, $alias) ];
322 =head2 resolve_condition($cond, $rel, $alias|$object)
324 Resolves the passed condition to a concrete query fragment. If given an alias,
325 returns a join condition; if given an object, inverts that object to produce
326 a related conditional from that object.
330 sub resolve_condition {
331 my ($self, $cond, $rel, $for) = @_;
333 if (ref $cond eq 'HASH') {
335 while (my ($k, $v) = each %{$cond}) {
336 # XXX should probably check these are valid columns
337 $k =~ s/^foreign\.// || die "Invalid rel cond key ${k}";
338 $v =~ s/^self\.// || die "Invalid rel cond val ${v}";
339 if (ref $for) { # Object
340 #warn "$self $k $for $v";
341 $ret{$k} = $for->get_column($v);
344 $ret{"${rel}.${k}"} = "${for}.${v}";
348 } elsif (ref $cond eq 'ARRAY') {
349 return [ map { $self->resolve_condition($_, $rel, $for) } @$cond ];
351 die("Can't handle this yet :(");
356 =head2 related_source($relname)
358 Returns the result source for the given relationship
363 my ($self, $rel) = @_;
364 return $self->schema->source($self->relationship_info($rel)->{source});
371 Matt S. Trout <mst@shadowcatsystems.co.uk>
375 You may distribute this code under the same terms as Perl itself.