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 _unique_constraints 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(@cols) : {};
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;
63 *add_column = \&add_columns;
67 $table->add_columns(qw/col1 col2 col3/);
69 $table->add_columns('col1' => \%col1_info, 'col2' => \%col2_info, ...);
71 Adds columns to the result source. If supplied key => hashref pairs uses
72 the hashref as the column_info for that column.
76 $table->add_column('col' => \%info?);
78 Convenience alias to add_columns
84 return $self->resultset_class->new($self);
89 if ($obj->has_column($col)) { ... }
91 Returns 1 if the source has a column of this name, 0 otherwise.
96 my ($self, $column) = @_;
97 return exists $self->_columns->{$column};
102 my $info = $obj->column_info($col);
104 Returns the column metadata hashref for a column.
109 my ($self, $column) = @_;
110 croak "No such column $column" unless exists $self->_columns->{$column};
111 if ( (! $self->_columns->{$column}->{data_type})
112 && $self->schema && $self->storage() ){
114 ############ eval for the case of storage without table
116 $info = $self->storage->columns_info_for ( $self->from() );
119 for my $col ( keys %{$self->_columns} ){
120 for my $i ( keys %{$info->{$col}} ){
121 $self->_columns()->{$col}->{$i} = $info->{$col}->{$i};
126 return $self->_columns->{$column};
131 my @column_names = $obj->columns;
133 Returns all column names in the order they were declared to add_columns
138 croak "columns() is a read-only accessor, did you mean add_columns()?" if (@_ > 1);
139 return @{shift->{_ordered_columns}||[]};
142 =head2 set_primary_key(@cols)
144 Defines one or more columns as primary key for this source. Should be
145 called after C<add_columns>.
147 Additionally, defines a unique constraint named C<primary>.
151 sub set_primary_key {
152 my ($self, @cols) = @_;
153 # check if primary key columns are valid columns
155 $self->throw("No such column $_ on table ".$self->name)
156 unless $self->has_column($_);
158 $self->_primaries(\@cols);
160 $self->add_unique_constraint(primary => \@cols);
163 =head2 primary_columns
165 Read-only accessor which returns the list of primary keys.
169 sub primary_columns {
170 return @{shift->_primaries||[]};
173 =head2 add_unique_constraint
175 Declare a unique constraint on this source. Call once for each unique
178 # For e.g. UNIQUE (column1, column2)
179 __PACKAGE__->add_unique_constraint(constraint_name => [ qw/column1 column2/ ]);
183 sub add_unique_constraint {
184 my ($self, $name, $cols) = @_;
187 $self->throw("No such column $_ on table ".$self->name)
188 unless $self->has_column($_);
191 my %unique_constraints = $self->unique_constraints;
192 $unique_constraints{$name} = $cols;
193 $self->_unique_constraints(\%unique_constraints);
196 =head2 unique_constraints
198 Read-only accessor which returns the list of unique constraints on this source.
202 sub unique_constraints {
203 return %{shift->_unique_constraints||{}};
208 Returns an expression of the source to be supplied to storage to specify
209 retrieval from this source; in the case of a database the required FROM clause
216 Returns the storage handle for the current schema
220 sub storage { shift->schema->storage; }
222 =head2 add_relationship
224 $source->add_relationship('relname', 'related_source', $cond, $attrs);
226 The relation name can be arbitrary, but must be unique for each relationship
227 attached to this result source. 'related_source' should be the name with
228 which the related result source was registered with the current schema
229 (for simple schemas this is usally either Some::Namespace::Foo or just Foo)
231 The condition needs to be an SQL::Abstract-style representation of the join
232 between the tables. For example, if you're creating a rel from Foo to Bar,
234 { 'foreign.foo_id' => 'self.id' }
236 will result in the JOIN clause
238 foo me JOIN bar bar ON bar.foo_id = me.id
240 You can specify as many foreign => self mappings as necessary.
242 Valid attributes are as follows:
248 Explicitly specifies the type of join to use in the relationship. Any SQL
249 join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in the SQL
250 command immediately before C<JOIN>.
254 An arrayref containing a list of accessors in the foreign class to proxy in
255 the main class. If, for example, you do the following:
257 __PACKAGE__->might_have(bar => 'Bar', undef, { proxy => qw[/ margle /] });
259 Then, assuming Bar has an accessor named margle, you can do:
261 my $obj = Foo->find(1);
262 $obj->margle(10); # set margle; Bar object is created if it doesn't exist
266 Specifies the type of accessor that should be created for the relationship.
267 Valid values are C<single> (for when there is only a single related object),
268 C<multi> (when there can be many), and C<filter> (for when there is a single
269 related object, but you also want the relationship accessor to double as
270 a column accessor). For C<multi> accessors, an add_to_* method is also
271 created, which calls C<create_related> for the relationship.
277 sub add_relationship {
278 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
279 croak "Can't create relationship without join condition" unless $cond;
282 my %rels = %{ $self->_relationships };
283 $rels{$rel} = { class => $f_source_name,
284 source => $f_source_name,
287 $self->_relationships(\%rels);
291 # XXX disabled. doesn't work properly currently. skip in tests.
293 my $f_source = $self->schema->source($f_source_name);
295 eval "require $f_source_name;";
297 die $@ unless $@ =~ /Can't locate/;
299 $f_source = $f_source_name->result_source;
300 #my $s_class = ref($self->schema);
301 #$f_source_name =~ m/^${s_class}::(.*)$/;
302 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
303 #$f_source = $self->schema->source($f_source_name);
305 return unless $f_source; # Can't test rel without f_source
307 eval { $self->resolve_join($rel, 'me') };
309 if ($@) { # If the resolve failed, back out and re-throw the error
310 delete $rels{$rel}; #
311 $self->_relationships(\%rels);
312 croak "Error creating relationship $rel: $@";
317 =head2 relationships()
319 Returns all valid relationship names for this source
324 return keys %{shift->_relationships};
327 =head2 relationship_info($relname)
329 Returns the relationship information for the specified relationship name
333 sub relationship_info {
334 my ($self, $rel) = @_;
335 return $self->_relationships->{$rel};
338 =head2 has_relationship($rel)
340 Returns 1 if the source has a relationship of this name, 0 otherwise.
344 sub has_relationship {
345 my ($self, $rel) = @_;
346 return exists $self->_relationships->{$rel};
349 =head2 resolve_join($relation)
351 Returns the join structure required for the related result source
356 my ($self, $join, $alias) = @_;
357 if (ref $join eq 'ARRAY') {
358 return map { $self->resolve_join($_, $alias) } @$join;
359 } elsif (ref $join eq 'HASH') {
360 return map { $self->resolve_join($_, $alias),
361 $self->related_source($_)->resolve_join($join->{$_}, $_) }
363 } elsif (ref $join) {
364 croak ("No idea how to resolve join reftype ".ref $join);
366 my $rel_info = $self->relationship_info($join);
367 croak("No such relationship ${join}") unless $rel_info;
368 my $type = $rel_info->{attrs}{join_type} || '';
369 return [ { $join => $self->related_source($join)->from,
370 -join_type => $type },
371 $self->resolve_condition($rel_info->{cond}, $join, $alias) ];
375 =head2 resolve_condition($cond, $rel, $alias|$object)
377 Resolves the passed condition to a concrete query fragment. If given an alias,
378 returns a join condition; if given an object, inverts that object to produce
379 a related conditional from that object.
383 sub resolve_condition {
384 my ($self, $cond, $rel, $for) = @_;
386 if (ref $cond eq 'HASH') {
388 while (my ($k, $v) = each %{$cond}) {
389 # XXX should probably check these are valid columns
390 $k =~ s/^foreign\.// || croak "Invalid rel cond key ${k}";
391 $v =~ s/^self\.// || croak "Invalid rel cond val ${v}";
392 if (ref $for) { # Object
393 #warn "$self $k $for $v";
394 $ret{$k} = $for->get_column($v);
397 $ret{"${rel}.${k}"} = "${for}.${v}";
401 } elsif (ref $cond eq 'ARRAY') {
402 return [ map { $self->resolve_condition($_, $rel, $for) } @$cond ];
404 die("Can't handle this yet :(");
409 =head2 related_source($relname)
411 Returns the result source for the given relationship
416 my ($self, $rel) = @_;
417 return $self->schema->source($self->relationship_info($rel)->{source});
424 Matt S. Trout <mst@shadowcatsystems.co.uk>
428 You may distribute this code under the same terms as Perl itself.