1 package DBIx::Class::ResultSource;
6 use DBIx::Class::ResultSet;
7 use Carp::Clan qw/^DBIx::Class/;
10 use base qw/DBIx::Class/;
11 __PACKAGE__->load_components(qw/AccessorGroup/);
13 __PACKAGE__->mk_group_accessors('simple' => qw/_ordered_columns
14 _columns _primaries _unique_constraints name resultset_attributes
15 schema from _relationships/);
17 __PACKAGE__->mk_group_accessors('component_class' => qw/resultset_class
18 result_class source_name/);
22 DBIx::Class::ResultSource - Result source object
28 A ResultSource is a component of a schema from which results can be directly
29 retrieved, most usually a table (see L<DBIx::Class::ResultSource::Table>)
36 my ($class, $attrs) = @_;
37 $class = ref $class if ref $class;
38 my $new = bless({ %{$attrs || {}}, _resultset => undef }, $class);
39 $new->{resultset_class} ||= 'DBIx::Class::ResultSet';
40 $new->{resultset_attributes} = { %{$new->{resultset_attributes} || {}} };
41 $new->{_ordered_columns} = [ @{$new->{_ordered_columns}||[]}];
42 $new->{_columns} = { %{$new->{_columns}||{}} };
43 $new->{_relationships} = { %{$new->{_relationships}||{}} };
44 $new->{name} ||= "!!NAME NOT SET!!";
45 $new->{_columns_info_loaded} ||= 0;
53 $table->add_columns(qw/col1 col2 col3/);
55 $table->add_columns('col1' => \%col1_info, 'col2' => \%col2_info, ...);
57 Adds columns to the result source. If supplied key => hashref pairs, uses
58 the hashref as the column_info for that column. Repeated calls of this
59 method will add more columns, not replace them.
61 The contents of the column_info are not set in stone. The following
62 keys are currently recognised/used by DBIx::Class:
68 Use this to set the name of the accessor for this column. If unset,
69 the name of the column will be used.
73 This contains the column type. It is automatically filled by the
74 L<SQL::Translator::Producer::DBIx::Class::File> producer, and the
75 L<DBIx::Class::Schema::Loader> module. If you do not enter a
76 data_type, DBIx::Class will attempt to retrieve it from the
77 database for you, using L<DBI>'s column_info method. The values of this
78 key are typically upper-cased.
80 Currently there is no standard set of values for the data_type. Use
81 whatever your database supports.
85 The length of your column, if it is a column type that can have a size
86 restriction. This is currently not used by DBIx::Class.
90 Set this to a true value for a columns that is allowed to contain
91 NULL values. This is currently not used by DBIx::Class.
93 =item is_auto_increment
95 Set this to a true value for a column whose value is somehow
96 automatically set. This is used to determine which columns to empty
97 when cloning objects using C<copy>.
101 Set this to a true value for a column that contains a key from a
102 foreign table. This is currently not used by DBIx::Class.
106 Set this to the default value which will be inserted into a column
107 by the database. Can contain either a value or a function. This is
108 currently not used by DBIx::Class.
112 Set this on a primary key column to the name of the sequence used to
113 generate a new key value. If not specified, L<DBIx::Class::PK::Auto>
114 will attempt to retrieve the name of the sequence from the database
121 $table->add_column('col' => \%info?);
123 Convenience alias to add_columns.
128 my ($self, @cols) = @_;
129 $self->_ordered_columns(\@cols) unless $self->_ordered_columns;
132 my $columns = $self->_columns;
133 while (my $col = shift @cols) {
134 # If next entry is { ... } use that for the column info, if not
135 # use an empty hashref
136 my $column_info = ref $cols[0] ? shift(@cols) : {};
137 push(@added, $col) unless exists $columns->{$col};
138 $columns->{$col} = $column_info;
140 push @{ $self->_ordered_columns }, @added;
144 *add_column = \&add_columns;
148 if ($obj->has_column($col)) { ... }
150 Returns true if the source has a column of this name, false otherwise.
155 my ($self, $column) = @_;
156 return exists $self->_columns->{$column};
161 my $info = $obj->column_info($col);
163 Returns the column metadata hashref for a column. See the description
164 of add_column for information on the contents of the hashref.
169 my ($self, $column) = @_;
170 $self->throw_exception("No such column $column")
171 unless exists $self->_columns->{$column};
172 #warn $self->{_columns_info_loaded}, "\n";
173 if ( ! $self->_columns->{$column}{data_type}
174 and ! $self->{_columns_info_loaded}
175 and $self->schema and $self->storage )
177 $self->{_columns_info_loaded}++;
179 # eval for the case of storage without table
180 eval { $info = $self->storage->columns_info_for($self->from) };
182 foreach my $col ( keys %{$self->_columns} ) {
183 foreach my $i ( keys %{$info->{$col}} ) {
184 $self->_columns->{$col}{$i} = $info->{$col}{$i};
189 return $self->_columns->{$column};
194 my @column_names = $obj->columns;
196 Returns all column names in the order they were declared to add_columns.
202 $self->throw_exception(
203 "columns() is a read-only accessor, did you mean add_columns()?"
205 return @{$self->{_ordered_columns}||[]};
208 =head2 remove_columns
210 $table->remove_columns(qw/col1 col2 col3/);
212 Removes columns from the result source.
216 $table->remove_column('col');
218 Convenience alias to remove_columns.
223 my ($self, @cols) = @_;
225 return unless $self->_ordered_columns;
227 my $columns = $self->_columns;
230 foreach my $col (@{$self->_ordered_columns}) {
231 push @remaining, $col unless grep(/$col/, @cols);
235 undef $columns->{$_};
238 $self->_ordered_columns(\@remaining);
241 *remove_column = \&remove_columns;
243 =head2 set_primary_key
247 =item Arguments: @cols
251 Defines one or more columns as primary key for this source. Should be
252 called after C<add_columns>.
254 Additionally, defines a unique constraint named C<primary>.
256 The primary key columns are used by L<DBIx::Class::PK::Auto> to
257 retrieve automatically created values from the database.
261 sub set_primary_key {
262 my ($self, @cols) = @_;
263 # check if primary key columns are valid columns
264 foreach my $col (@cols) {
265 $self->throw_exception("No such column $col on table " . $self->name)
266 unless $self->has_column($col);
268 $self->_primaries(\@cols);
270 $self->add_unique_constraint(primary => \@cols);
273 =head2 primary_columns
275 Read-only accessor which returns the list of primary keys.
279 sub primary_columns {
280 return @{shift->_primaries||[]};
283 =head2 add_unique_constraint
285 Declare a unique constraint on this source. Call once for each unique
288 # For UNIQUE (column1, column2)
289 __PACKAGE__->add_unique_constraint(
290 constraint_name => [ qw/column1 column2/ ],
293 Unique constraints are used, for example, when you call
294 L<DBIx::Class::ResultSet/find>. Only columns in the constraint are searched.
298 sub add_unique_constraint {
299 my ($self, $name, $cols) = @_;
301 foreach my $col (@$cols) {
302 $self->throw_exception("No such column $col on table " . $self->name)
303 unless $self->has_column($col);
306 my %unique_constraints = $self->unique_constraints;
307 $unique_constraints{$name} = $cols;
308 $self->_unique_constraints(\%unique_constraints);
311 =head2 unique_constraints
313 Read-only accessor which returns the list of unique constraints on this source.
317 sub unique_constraints {
318 return %{shift->_unique_constraints||{}};
321 =head2 unique_constraint_names
323 Returns the list of unique constraint names defined on this source.
327 sub unique_constraint_names {
330 my %unique_constraints = $self->unique_constraints;
332 return keys %unique_constraints;
335 =head2 unique_constraint_columns
337 Returns the list of columns that make up the specified unique constraint.
341 sub unique_constraint_columns {
342 my ($self, $constraint_name) = @_;
344 my %unique_constraints = $self->unique_constraints;
346 $self->throw_exception(
347 "Unknown unique constraint $constraint_name on '" . $self->name . "'"
348 ) unless exists $unique_constraints{$constraint_name};
350 return @{ $unique_constraints{$constraint_name} };
355 Returns an expression of the source to be supplied to storage to specify
356 retrieval from this source. In the case of a database, the required FROM
361 Returns the L<DBIx::Class::Schema> object that this result source
366 Returns the storage handle for the current schema.
368 See also: L<DBIx::Class::Storage>
372 sub storage { shift->schema->storage; }
374 =head2 add_relationship
376 $source->add_relationship('relname', 'related_source', $cond, $attrs);
378 The relationship name can be arbitrary, but must be unique for each
379 relationship attached to this result source. 'related_source' should
380 be the name with which the related result source was registered with
381 the current schema. For example:
383 $schema->source('Book')->add_relationship('reviews', 'Review', {
384 'foreign.book_id' => 'self.id',
387 The condition C<$cond> needs to be an L<SQL::Abstract>-style
388 representation of the join between the tables. For example, if you're
389 creating a rel from Author to Book,
391 { 'foreign.author_id' => 'self.id' }
393 will result in the JOIN clause
395 author me JOIN book foreign ON foreign.author_id = me.id
397 You can specify as many foreign => self mappings as necessary.
399 Valid attributes are as follows:
405 Explicitly specifies the type of join to use in the relationship. Any
406 SQL join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in
407 the SQL command immediately before C<JOIN>.
411 An arrayref containing a list of accessors in the foreign class to proxy in
412 the main class. If, for example, you do the following:
414 CD->might_have(liner_notes => 'LinerNotes', undef, {
415 proxy => [ qw/notes/ ],
418 Then, assuming LinerNotes has an accessor named notes, you can do:
420 my $cd = CD->find(1);
421 # set notes -- LinerNotes object is created if it doesn't exist
422 $cd->notes('Notes go here');
426 Specifies the type of accessor that should be created for the
427 relationship. Valid values are C<single> (for when there is only a single
428 related object), C<multi> (when there can be many), and C<filter> (for
429 when there is a single related object, but you also want the relationship
430 accessor to double as a column accessor). For C<multi> accessors, an
431 add_to_* method is also created, which calls C<create_related> for the
438 sub add_relationship {
439 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
440 $self->throw_exception("Can't create relationship without join condition")
444 my %rels = %{ $self->_relationships };
445 $rels{$rel} = { class => $f_source_name,
446 source => $f_source_name,
449 $self->_relationships(\%rels);
453 # XXX disabled. doesn't work properly currently. skip in tests.
455 my $f_source = $self->schema->source($f_source_name);
457 eval "require $f_source_name;";
459 die $@ unless $@ =~ /Can't locate/;
461 $f_source = $f_source_name->result_source;
462 #my $s_class = ref($self->schema);
463 #$f_source_name =~ m/^${s_class}::(.*)$/;
464 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
465 #$f_source = $self->schema->source($f_source_name);
467 return unless $f_source; # Can't test rel without f_source
469 eval { $self->resolve_join($rel, 'me') };
471 if ($@) { # If the resolve failed, back out and re-throw the error
472 delete $rels{$rel}; #
473 $self->_relationships(\%rels);
474 $self->throw_exception("Error creating relationship $rel: $@");
481 Returns all relationship names for this source.
486 return keys %{shift->_relationships};
489 =head2 relationship_info
493 =item Arguments: $relname
497 Returns a hash of relationship information for the specified relationship
502 sub relationship_info {
503 my ($self, $rel) = @_;
504 return $self->_relationships->{$rel};
507 =head2 has_relationship
511 =item Arguments: $rel
515 Returns true if the source has a relationship of this name, false otherwise.
519 sub has_relationship {
520 my ($self, $rel) = @_;
521 return exists $self->_relationships->{$rel};
524 =head2 reverse_relationship_info
528 =item Arguments: $relname
532 Returns an array of hash references of relationship information for
533 the other side of the specified relationship name.
537 sub reverse_relationship_info {
538 my ($self, $rel) = @_;
539 my $rel_info = $self->relationship_info($rel);
542 return $ret unless ((ref $rel_info->{cond}) eq 'HASH');
544 my @cond = keys(%{$rel_info->{cond}});
545 my @refkeys = map {/^\w+\.(\w+)$/} @cond;
546 my @keys = map {$rel_info->{cond}->{$_} =~ /^\w+\.(\w+)$/} @cond;
548 # Get the related result source for this relationship
549 my $othertable = $self->related_source($rel);
551 # Get all the relationships for that source that related to this source
552 # whose foreign column set are our self columns on $rel and whose self
553 # columns are our foreign columns on $rel.
554 my @otherrels = $othertable->relationships();
555 my $otherrelationship;
556 foreach my $otherrel (@otherrels) {
557 my $otherrel_info = $othertable->relationship_info($otherrel);
559 my $back = $othertable->related_source($otherrel);
560 next unless $back->name eq $self->name;
564 if (ref $otherrel_info->{cond} eq 'HASH') {
565 @othertestconds = ($otherrel_info->{cond});
567 elsif (ref $otherrel_info->{cond} eq 'ARRAY') {
568 @othertestconds = @{$otherrel_info->{cond}};
574 foreach my $othercond (@othertestconds) {
575 my @other_cond = keys(%$othercond);
576 my @other_refkeys = map {/^\w+\.(\w+)$/} @other_cond;
577 my @other_keys = map {$othercond->{$_} =~ /^\w+\.(\w+)$/} @other_cond;
578 next if (!$self->compare_relationship_keys(\@refkeys, \@other_keys) ||
579 !$self->compare_relationship_keys(\@other_refkeys, \@keys));
580 $ret->{$otherrel} = $otherrel_info;
586 =head2 compare_relationship_keys
590 =item Arguments: $keys1, $keys2
594 Returns true if both sets of keynames are the same, false otherwise.
598 sub compare_relationship_keys {
599 my ($self, $keys1, $keys2) = @_;
601 # Make sure every keys1 is in keys2
603 foreach my $key (@$keys1) {
605 foreach my $prim (@$keys2) {
614 # Make sure every key2 is in key1
616 foreach my $prim (@$keys2) {
618 foreach my $key (@$keys1) {
635 =item Arguments: $relation
639 Returns the join structure required for the related result source.
644 my ($self, $join, $alias, $seen) = @_;
646 if (ref $join eq 'ARRAY') {
647 return map { $self->resolve_join($_, $alias, $seen) } @$join;
648 } elsif (ref $join eq 'HASH') {
651 my $as = ($seen->{$_} ? $_.'_'.($seen->{$_}+1) : $_);
652 ($self->resolve_join($_, $alias, $seen),
653 $self->related_source($_)->resolve_join($join->{$_}, $as, $seen));
655 } elsif (ref $join) {
656 $self->throw_exception("No idea how to resolve join reftype ".ref $join);
658 my $count = ++$seen->{$join};
659 #use Data::Dumper; warn Dumper($seen);
660 my $as = ($count > 1 ? "${join}_${count}" : $join);
661 my $rel_info = $self->relationship_info($join);
662 $self->throw_exception("No such relationship ${join}") unless $rel_info;
663 my $type = $rel_info->{attrs}{join_type} || '';
664 return [ { $as => $self->related_source($join)->from,
665 -join_type => $type },
666 $self->resolve_condition($rel_info->{cond}, $as, $alias) ];
670 =head2 resolve_condition
674 =item Arguments: $cond, $as, $alias|$object
678 Resolves the passed condition to a concrete query fragment. If given an alias,
679 returns a join condition; if given an object, inverts that object to produce
680 a related conditional from that object.
684 sub resolve_condition {
685 my ($self, $cond, $as, $for) = @_;
687 if (ref $cond eq 'HASH') {
689 foreach my $k (keys %{$cond}) {
691 # XXX should probably check these are valid columns
692 $k =~ s/^foreign\.// ||
693 $self->throw_exception("Invalid rel cond key ${k}");
695 $self->throw_exception("Invalid rel cond val ${v}");
696 if (ref $for) { # Object
697 #warn "$self $k $for $v";
698 $ret{$k} = $for->get_column($v);
700 } elsif (!defined $for) { # undef, i.e. "no object"
702 } elsif (ref $as) { # reverse object
703 $ret{$v} = $as->get_column($k);
704 } elsif (!defined $as) { # undef, i.e. "no reverse object"
707 $ret{"${as}.${k}"} = "${for}.${v}";
711 } elsif (ref $cond eq 'ARRAY') {
712 return [ map { $self->resolve_condition($_, $as, $for) } @$cond ];
714 die("Can't handle this yet :(");
718 =head2 resolve_prefetch
722 =item Arguments: hashref/arrayref/scalar
726 Accepts one or more relationships for the current source and returns an
727 array of column names for each of those relationships. Column names are
728 prefixed relative to the current source, in accordance with where they appear
729 in the supplied relationships. Examples:
731 my $source = $schema->resultset('Tag')->source;
732 @columns = $source->resolve_prefetch( { cd => 'artist' } );
740 # 'cd.artist.artistid',
744 @columns = $source->resolve_prefetch( qw[/ cd /] );
754 $source = $schema->resultset('CD')->source;
755 @columns = $source->resolve_prefetch( qw[/ artist producer /] );
761 # 'producer.producerid',
767 sub resolve_prefetch {
768 my ($self, $pre, $alias, $seen, $order, $collapse) = @_;
770 #$alias ||= $self->name;
771 #warn $alias, Dumper $pre;
772 if( ref $pre eq 'ARRAY' ) {
774 map { $self->resolve_prefetch( $_, $alias, $seen, $order, $collapse ) }
777 elsif( ref $pre eq 'HASH' ) {
780 $self->resolve_prefetch($_, $alias, $seen, $order, $collapse),
781 $self->related_source($_)->resolve_prefetch(
782 $pre->{$_}, "${alias}.$_", $seen, $order, $collapse)
788 $self->throw_exception(
789 "don't know how to resolve prefetch reftype ".ref($pre));
792 my $count = ++$seen->{$pre};
793 my $as = ($count > 1 ? "${pre}_${count}" : $pre);
794 my $rel_info = $self->relationship_info( $pre );
795 $self->throw_exception( $self->name . " has no such relationship '$pre'" )
797 my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
798 my $rel_source = $self->related_source($pre);
800 if (exists $rel_info->{attrs}{accessor}
801 && $rel_info->{attrs}{accessor} eq 'multi') {
802 $self->throw_exception(
803 "Can't prefetch has_many ${pre} (join cond too complex)")
804 unless ref($rel_info->{cond}) eq 'HASH';
805 my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
806 keys %{$rel_info->{cond}};
807 $collapse->{"${as_prefix}${pre}"} = \@key;
808 my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY'
809 ? @{$rel_info->{attrs}{order_by}}
810 : (defined $rel_info->{attrs}{order_by}
811 ? ($rel_info->{attrs}{order_by})
813 push(@$order, map { "${as}.$_" } (@key, @ord));
816 return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
817 $rel_source->columns;
818 #warn $alias, Dumper (\@ret);
823 =head2 related_source
827 =item Arguments: $relname
831 Returns the result source object for the given relationship.
836 my ($self, $rel) = @_;
837 if( !$self->has_relationship( $rel ) ) {
838 $self->throw_exception("No such relationship '$rel'");
840 return $self->schema->source($self->relationship_info($rel)->{source});
847 =item Arguments: $relname
851 Returns the class name for objects in the given relationship.
856 my ($self, $rel) = @_;
857 if( !$self->has_relationship( $rel ) ) {
858 $self->throw_exception("No such relationship '$rel'");
860 return $self->schema->class($self->relationship_info($rel)->{source});
865 Returns a resultset for the given source. This will initially be created
868 $self->resultset_class->new($self, $self->resultset_attributes)
870 but is cached from then on unless resultset_class changes.
872 =head2 resultset_class
874 Set the class of the resultset, this is useful if you want to create your
875 own resultset methods. Create your own class derived from
876 L<DBIx::Class::ResultSet>, and set it here.
878 =head2 resultset_attributes
880 Specify here any attributes you wish to pass to your specialised resultset.
886 $self->throw_exception(
887 'resultset does not take any arguments. If you want another resultset, '.
888 'call it on the schema instead.'
891 # disabled until we can figure out a way to do it without consistency issues
893 #return $self->{_resultset}
894 # if ref $self->{_resultset} eq $self->resultset_class;
895 #return $self->{_resultset} =
897 return $self->resultset_class->new(
898 $self, $self->{resultset_attributes}
906 =item Arguments: $source_name
910 Set the name of the result source when it is loaded into a schema.
911 This is usefull if you want to refer to a result source by a name other than
914 package ArchivedBooks;
915 use base qw/DBIx::Class/;
916 __PACKAGE__->table('books_archive');
917 __PACKAGE__->source_name('Books');
919 # from your schema...
920 $schema->resultset('Books')->find(1);
922 =head2 throw_exception
924 See L<DBIx::Class::Schema/"throw_exception">.
928 sub throw_exception {
930 if (defined $self->schema) {
931 $self->schema->throw_exception(@_);
939 Matt S. Trout <mst@shadowcatsystems.co.uk>
943 You may distribute this code under the same terms as Perl itself.