1 package DBIx::Class::ResultSource;
6 use DBIx::Class::ResultSet;
12 use base qw/DBIx::Class/;
13 __PACKAGE__->load_components(qw/AccessorGroup/);
15 __PACKAGE__->mk_group_accessors('simple' =>
16 qw/_ordered_columns _columns _primaries _unique_constraints name resultset_class result_class schema from _relationships/);
20 DBIx::Class::ResultSource - Result source object
26 A ResultSource is a component of a schema from which results can be directly
27 retrieved, most usually a table (see L<DBIx::Class::ResultSource::Table>)
34 my ($class, $attrs) = @_;
35 $class = ref $class if ref $class;
36 my $new = bless({ %{$attrs || {}} }, $class);
37 $new->{resultset_class} ||= 'DBIx::Class::ResultSet';
38 $new->{_ordered_columns} = [ @{$new->{_ordered_columns}||[]}];
39 $new->{_columns} = { %{$new->{_columns}||{}} };
40 $new->{_relationships} = { %{$new->{_relationships}||{}} };
41 $new->{name} ||= "!!NAME NOT SET!!";
46 my ($self, @cols) = @_;
47 $self->_ordered_columns( \@cols )
48 if !$self->_ordered_columns;
50 my $columns = $self->_columns;
51 while (my $col = shift @cols) {
53 my $column_info = ref $cols[0] ? shift(@cols) : {};
54 # If next entry is { ... } use that for the column info, if not
55 # use an empty hashref
57 push(@added, $col) unless exists $columns->{$col};
59 $columns->{$col} = $column_info;
61 push @{ $self->_ordered_columns }, @added;
65 *add_column = \&add_columns;
69 $table->add_columns(qw/col1 col2 col3/);
71 $table->add_columns('col1' => \%col1_info, 'col2' => \%col2_info, ...);
73 Adds columns to the result source. If supplied key => hashref pairs uses
74 the hashref as the column_info for that column.
78 $table->add_column('col' => \%info?);
80 Convenience alias to add_columns
86 return $self->resultset_class->new($self);
91 if ($obj->has_column($col)) { ... }
93 Returns 1 if the source has a column of this name, 0 otherwise.
98 my ($self, $column) = @_;
99 return exists $self->_columns->{$column};
104 my $info = $obj->column_info($col);
106 Returns the column metadata hashref for a column.
111 my ($self, $column) = @_;
112 croak "No such column $column" unless exists $self->_columns->{$column};
113 if ( (! $self->_columns->{$column}->{data_type})
114 && $self->schema && $self->storage() ){
116 ############ eval for the case of storage without table
118 $info = $self->storage->columns_info_for ( $self->from() );
121 for my $col ( keys %{$self->_columns} ){
122 for my $i ( keys %{$info->{$col}} ){
123 $self->_columns()->{$col}->{$i} = $info->{$col}->{$i};
128 return $self->_columns->{$column};
133 my @column_names = $obj->columns;
135 Returns all column names in the order they were declared to add_columns
140 croak "columns() is a read-only accessor, did you mean add_columns()?" if (@_ > 1);
141 return @{shift->{_ordered_columns}||[]};
144 =head2 set_primary_key(@cols)
146 Defines one or more columns as primary key for this source. Should be
147 called after C<add_columns>.
149 Additionally, defines a unique constraint named C<primary>.
153 sub set_primary_key {
154 my ($self, @cols) = @_;
155 # check if primary key columns are valid columns
157 $self->throw("No such column $_ on table ".$self->name)
158 unless $self->has_column($_);
160 $self->_primaries(\@cols);
162 $self->add_unique_constraint(primary => \@cols);
165 =head2 primary_columns
167 Read-only accessor which returns the list of primary keys.
171 sub primary_columns {
172 return @{shift->_primaries||[]};
175 =head2 add_unique_constraint
177 Declare a unique constraint on this source. Call once for each unique
180 # For e.g. UNIQUE (column1, column2)
181 __PACKAGE__->add_unique_constraint(constraint_name => [ qw/column1 column2/ ]);
185 sub add_unique_constraint {
186 my ($self, $name, $cols) = @_;
189 $self->throw("No such column $_ on table ".$self->name)
190 unless $self->has_column($_);
193 my %unique_constraints = $self->unique_constraints;
194 $unique_constraints{$name} = $cols;
195 $self->_unique_constraints(\%unique_constraints);
198 =head2 unique_constraints
200 Read-only accessor which returns the list of unique constraints on this source.
204 sub unique_constraints {
205 return %{shift->_unique_constraints||{}};
210 Returns an expression of the source to be supplied to storage to specify
211 retrieval from this source; in the case of a database the required FROM clause
218 Returns the storage handle for the current schema
222 sub storage { shift->schema->storage; }
224 =head2 add_relationship
226 $source->add_relationship('relname', 'related_source', $cond, $attrs);
228 The relation name can be arbitrary, but must be unique for each relationship
229 attached to this result source. 'related_source' should be the name with
230 which the related result source was registered with the current schema
231 (for simple schemas this is usally either Some::Namespace::Foo or just Foo)
233 The condition needs to be an SQL::Abstract-style representation of the join
234 between the tables. For example, if you're creating a rel from Foo to Bar,
236 { 'foreign.foo_id' => 'self.id' }
238 will result in the JOIN clause
240 foo me JOIN bar bar ON bar.foo_id = me.id
242 You can specify as many foreign => self mappings as necessary.
244 Valid attributes are as follows:
250 Explicitly specifies the type of join to use in the relationship. Any SQL
251 join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in the SQL
252 command immediately before C<JOIN>.
256 An arrayref containing a list of accessors in the foreign class to proxy in
257 the main class. If, for example, you do the following:
259 __PACKAGE__->might_have(bar => 'Bar', undef, { proxy => qw[/ margle /] });
261 Then, assuming Bar has an accessor named margle, you can do:
263 my $obj = Foo->find(1);
264 $obj->margle(10); # set margle; Bar object is created if it doesn't exist
268 Specifies the type of accessor that should be created for the relationship.
269 Valid values are C<single> (for when there is only a single related object),
270 C<multi> (when there can be many), and C<filter> (for when there is a single
271 related object, but you also want the relationship accessor to double as
272 a column accessor). For C<multi> accessors, an add_to_* method is also
273 created, which calls C<create_related> for the relationship.
279 sub add_relationship {
280 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
281 croak "Can't create relationship without join condition" unless $cond;
284 my %rels = %{ $self->_relationships };
285 $rels{$rel} = { class => $f_source_name,
286 source => $f_source_name,
289 $self->_relationships(\%rels);
293 # XXX disabled. doesn't work properly currently. skip in tests.
295 my $f_source = $self->schema->source($f_source_name);
297 eval "require $f_source_name;";
299 die $@ unless $@ =~ /Can't locate/;
301 $f_source = $f_source_name->result_source;
302 #my $s_class = ref($self->schema);
303 #$f_source_name =~ m/^${s_class}::(.*)$/;
304 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
305 #$f_source = $self->schema->source($f_source_name);
307 return unless $f_source; # Can't test rel without f_source
309 eval { $self->resolve_join($rel, 'me') };
311 if ($@) { # If the resolve failed, back out and re-throw the error
312 delete $rels{$rel}; #
313 $self->_relationships(\%rels);
314 croak "Error creating relationship $rel: $@";
319 =head2 relationships()
321 Returns all valid relationship names for this source
326 return keys %{shift->_relationships};
329 =head2 relationship_info($relname)
331 Returns the relationship information for the specified relationship name
335 sub relationship_info {
336 my ($self, $rel) = @_;
337 return $self->_relationships->{$rel};
340 =head2 has_relationship($rel)
342 Returns 1 if the source has a relationship of this name, 0 otherwise.
346 sub has_relationship {
347 my ($self, $rel) = @_;
348 return exists $self->_relationships->{$rel};
351 =head2 resolve_join($relation)
353 Returns the join structure required for the related result source
358 my ($self, $join, $alias) = @_;
359 if (ref $join eq 'ARRAY') {
360 return map { $self->resolve_join($_, $alias) } @$join;
361 } elsif (ref $join eq 'HASH') {
362 return map { $self->resolve_join($_, $alias),
363 $self->related_source($_)->resolve_join($join->{$_}, $_) }
365 } elsif (ref $join) {
366 croak ("No idea how to resolve join reftype ".ref $join);
368 my $rel_info = $self->relationship_info($join);
369 croak("No such relationship ${join}") unless $rel_info;
370 my $type = $rel_info->{attrs}{join_type} || '';
371 return [ { $join => $self->related_source($join)->from,
372 -join_type => $type },
373 $self->resolve_condition($rel_info->{cond}, $join, $alias) ];
377 =head2 resolve_condition($cond, $rel, $alias|$object)
379 Resolves the passed condition to a concrete query fragment. If given an alias,
380 returns a join condition; if given an object, inverts that object to produce
381 a related conditional from that object.
385 sub resolve_condition {
386 my ($self, $cond, $rel, $for) = @_;
388 if (ref $cond eq 'HASH') {
390 while (my ($k, $v) = each %{$cond}) {
391 # XXX should probably check these are valid columns
392 $k =~ s/^foreign\.// || croak "Invalid rel cond key ${k}";
393 $v =~ s/^self\.// || croak "Invalid rel cond val ${v}";
394 if (ref $for) { # Object
395 #warn "$self $k $for $v";
396 $ret{$k} = $for->get_column($v);
399 $ret{"${rel}.${k}"} = "${for}.${v}";
403 } elsif (ref $cond eq 'ARRAY') {
404 return [ map { $self->resolve_condition($_, $rel, $for) } @$cond ];
406 die("Can't handle this yet :(");
411 =head2 related_source($relname)
413 Returns the result source for the given relationship
418 my ($self, $rel) = @_;
419 if( !$self->has_relationship( $rel ) ) {
420 croak "No such relationship '$rel'";
422 return $self->schema->source($self->relationship_info($rel)->{source});
429 Matt S. Trout <mst@shadowcatsystems.co.uk>
433 You may distribute this code under the same terms as Perl itself.