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
363 Returns the storage handle for the current schema.
365 See also: L<DBIx::Class::Storage>
369 sub storage { shift->schema->storage; }
371 =head2 add_relationship
373 $source->add_relationship('relname', 'related_source', $cond, $attrs);
375 The relationship name can be arbitrary, but must be unique for each
376 relationship attached to this result source. 'related_source' should
377 be the name with which the related result source was registered with
378 the current schema. For example:
380 $schema->source('Book')->add_relationship('reviews', 'Review', {
381 'foreign.book_id' => 'self.id',
384 The condition C<$cond> needs to be an L<SQL::Abstract>-style
385 representation of the join between the tables. For example, if you're
386 creating a rel from Author to Book,
388 { 'foreign.author_id' => 'self.id' }
390 will result in the JOIN clause
392 author me JOIN book foreign ON foreign.author_id = me.id
394 You can specify as many foreign => self mappings as necessary.
396 Valid attributes are as follows:
402 Explicitly specifies the type of join to use in the relationship. Any
403 SQL join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in
404 the SQL command immediately before C<JOIN>.
408 An arrayref containing a list of accessors in the foreign class to proxy in
409 the main class. If, for example, you do the following:
411 CD->might_have(liner_notes => 'LinerNotes', undef, {
412 proxy => [ qw/notes/ ],
415 Then, assuming LinerNotes has an accessor named notes, you can do:
417 my $cd = CD->find(1);
418 # set notes -- LinerNotes object is created if it doesn't exist
419 $cd->notes('Notes go here');
423 Specifies the type of accessor that should be created for the
424 relationship. Valid values are C<single> (for when there is only a single
425 related object), C<multi> (when there can be many), and C<filter> (for
426 when there is a single related object, but you also want the relationship
427 accessor to double as a column accessor). For C<multi> accessors, an
428 add_to_* method is also created, which calls C<create_related> for the
435 sub add_relationship {
436 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
437 $self->throw_exception("Can't create relationship without join condition")
441 my %rels = %{ $self->_relationships };
442 $rels{$rel} = { class => $f_source_name,
443 source => $f_source_name,
446 $self->_relationships(\%rels);
450 # XXX disabled. doesn't work properly currently. skip in tests.
452 my $f_source = $self->schema->source($f_source_name);
454 eval "require $f_source_name;";
456 die $@ unless $@ =~ /Can't locate/;
458 $f_source = $f_source_name->result_source;
459 #my $s_class = ref($self->schema);
460 #$f_source_name =~ m/^${s_class}::(.*)$/;
461 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
462 #$f_source = $self->schema->source($f_source_name);
464 return unless $f_source; # Can't test rel without f_source
466 eval { $self->resolve_join($rel, 'me') };
468 if ($@) { # If the resolve failed, back out and re-throw the error
469 delete $rels{$rel}; #
470 $self->_relationships(\%rels);
471 $self->throw_exception("Error creating relationship $rel: $@");
478 Returns all relationship names for this source.
483 return keys %{shift->_relationships};
486 =head2 relationship_info
490 =item Arguments: $relname
494 Returns a hash of relationship information for the specified relationship
499 sub relationship_info {
500 my ($self, $rel) = @_;
501 return $self->_relationships->{$rel};
504 =head2 has_relationship
508 =item Arguments: $rel
512 Returns true if the source has a relationship of this name, false otherwise.
516 sub has_relationship {
517 my ($self, $rel) = @_;
518 return exists $self->_relationships->{$rel};
521 =head2 reverse_relationship_info
525 =item Arguments: $relname
529 Returns an array of hash references of relationship information for
530 the other side of the specified relationship name.
534 sub reverse_relationship_info {
535 my ($self, $rel) = @_;
536 my $rel_info = $self->relationship_info($rel);
539 return $ret unless ((ref $rel_info->{cond}) eq 'HASH');
541 my @cond = keys(%{$rel_info->{cond}});
542 my @refkeys = map {/^\w+\.(\w+)$/} @cond;
543 my @keys = map {$rel_info->{cond}->{$_} =~ /^\w+\.(\w+)$/} @cond;
545 # Get the related result source for this relationship
546 my $othertable = $self->related_source($rel);
548 # Get all the relationships for that source that related to this source
549 # whose foreign column set are our self columns on $rel and whose self
550 # columns are our foreign columns on $rel.
551 my @otherrels = $othertable->relationships();
552 my $otherrelationship;
553 foreach my $otherrel (@otherrels) {
554 my $otherrel_info = $othertable->relationship_info($otherrel);
556 my $back = $othertable->related_source($otherrel);
557 next unless $back->name eq $self->name;
561 if (ref $otherrel_info->{cond} eq 'HASH') {
562 @othertestconds = ($otherrel_info->{cond});
564 elsif (ref $otherrel_info->{cond} eq 'ARRAY') {
565 @othertestconds = @{$otherrel_info->{cond}};
571 foreach my $othercond (@othertestconds) {
572 my @other_cond = keys(%$othercond);
573 my @other_refkeys = map {/^\w+\.(\w+)$/} @other_cond;
574 my @other_keys = map {$othercond->{$_} =~ /^\w+\.(\w+)$/} @other_cond;
575 next if (!$self->compare_relationship_keys(\@refkeys, \@other_keys) ||
576 !$self->compare_relationship_keys(\@other_refkeys, \@keys));
577 $ret->{$otherrel} = $otherrel_info;
583 =head2 compare_relationship_keys
587 =item Arguments: $keys1, $keys2
591 Returns true if both sets of keynames are the same, false otherwise.
595 sub compare_relationship_keys {
596 my ($self, $keys1, $keys2) = @_;
598 # Make sure every keys1 is in keys2
600 foreach my $key (@$keys1) {
602 foreach my $prim (@$keys2) {
611 # Make sure every key2 is in key1
613 foreach my $prim (@$keys2) {
615 foreach my $key (@$keys1) {
632 =item Arguments: $relation
636 Returns the join structure required for the related result source.
641 my ($self, $join, $alias, $seen) = @_;
643 if (ref $join eq 'ARRAY') {
644 return map { $self->resolve_join($_, $alias, $seen) } @$join;
645 } elsif (ref $join eq 'HASH') {
648 my $as = ($seen->{$_} ? $_.'_'.($seen->{$_}+1) : $_);
649 ($self->resolve_join($_, $alias, $seen),
650 $self->related_source($_)->resolve_join($join->{$_}, $as, $seen));
652 } elsif (ref $join) {
653 $self->throw_exception("No idea how to resolve join reftype ".ref $join);
655 my $count = ++$seen->{$join};
656 #use Data::Dumper; warn Dumper($seen);
657 my $as = ($count > 1 ? "${join}_${count}" : $join);
658 my $rel_info = $self->relationship_info($join);
659 $self->throw_exception("No such relationship ${join}") unless $rel_info;
660 my $type = $rel_info->{attrs}{join_type} || '';
661 return [ { $as => $self->related_source($join)->from,
662 -join_type => $type },
663 $self->resolve_condition($rel_info->{cond}, $as, $alias) ];
667 =head2 resolve_condition
671 =item Arguments: $cond, $as, $alias|$object
675 Resolves the passed condition to a concrete query fragment. If given an alias,
676 returns a join condition; if given an object, inverts that object to produce
677 a related conditional from that object.
681 sub resolve_condition {
682 my ($self, $cond, $as, $for) = @_;
684 if (ref $cond eq 'HASH') {
686 while (my ($k, $v) = each %{$cond}) {
687 # XXX should probably check these are valid columns
688 $k =~ s/^foreign\.// ||
689 $self->throw_exception("Invalid rel cond key ${k}");
691 $self->throw_exception("Invalid rel cond val ${v}");
692 if (ref $for) { # Object
693 #warn "$self $k $for $v";
694 $ret{$k} = $for->get_column($v);
696 } elsif (ref $as) { # reverse object
697 $ret{$v} = $as->get_column($k);
699 $ret{"${as}.${k}"} = "${for}.${v}";
703 } elsif (ref $cond eq 'ARRAY') {
704 return [ map { $self->resolve_condition($_, $as, $for) } @$cond ];
706 die("Can't handle this yet :(");
710 =head2 resolve_prefetch
714 =item Arguments: hashref/arrayref/scalar
718 Accepts one or more relationships for the current source and returns an
719 array of column names for each of those relationships. Column names are
720 prefixed relative to the current source, in accordance with where they appear
721 in the supplied relationships. Examples:
723 my $source = $schema->resultset('Tag')->source;
724 @columns = $source->resolve_prefetch( { cd => 'artist' } );
732 # 'cd.artist.artistid',
736 @columns = $source->resolve_prefetch( qw[/ cd /] );
746 $source = $schema->resultset('CD')->source;
747 @columns = $source->resolve_prefetch( qw[/ artist producer /] );
753 # 'producer.producerid',
759 sub resolve_prefetch {
760 my ($self, $pre, $alias, $seen, $order, $collapse) = @_;
762 #$alias ||= $self->name;
763 #warn $alias, Dumper $pre;
764 if( ref $pre eq 'ARRAY' ) {
766 map { $self->resolve_prefetch( $_, $alias, $seen, $order, $collapse ) }
769 elsif( ref $pre eq 'HASH' ) {
772 $self->resolve_prefetch($_, $alias, $seen, $order, $collapse),
773 $self->related_source($_)->resolve_prefetch(
774 $pre->{$_}, "${alias}.$_", $seen, $order, $collapse)
780 $self->throw_exception(
781 "don't know how to resolve prefetch reftype ".ref($pre));
784 my $count = ++$seen->{$pre};
785 my $as = ($count > 1 ? "${pre}_${count}" : $pre);
786 my $rel_info = $self->relationship_info( $pre );
787 $self->throw_exception( $self->name . " has no such relationship '$pre'" )
789 my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
790 my $rel_source = $self->related_source($pre);
792 if (exists $rel_info->{attrs}{accessor}
793 && $rel_info->{attrs}{accessor} eq 'multi') {
794 $self->throw_exception(
795 "Can't prefetch has_many ${pre} (join cond too complex)")
796 unless ref($rel_info->{cond}) eq 'HASH';
797 my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
798 keys %{$rel_info->{cond}};
799 $collapse->{"${as_prefix}${pre}"} = \@key;
800 my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY'
801 ? @{$rel_info->{attrs}{order_by}}
802 : (defined $rel_info->{attrs}{order_by}
803 ? ($rel_info->{attrs}{order_by})
805 push(@$order, map { "${as}.$_" } (@key, @ord));
808 return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
809 $rel_source->columns;
810 #warn $alias, Dumper (\@ret);
815 =head2 related_source
819 =item Arguments: $relname
823 Returns the result source object for the given relationship.
828 my ($self, $rel) = @_;
829 if( !$self->has_relationship( $rel ) ) {
830 $self->throw_exception("No such relationship '$rel'");
832 return $self->schema->source($self->relationship_info($rel)->{source});
839 =item Arguments: $relname
843 Returns the class name for objects in the given relationship.
848 my ($self, $rel) = @_;
849 if( !$self->has_relationship( $rel ) ) {
850 $self->throw_exception("No such relationship '$rel'");
852 return $self->schema->class($self->relationship_info($rel)->{source});
857 Returns a resultset for the given source. This will initially be created
860 $self->resultset_class->new($self, $self->resultset_attributes)
862 but is cached from then on unless resultset_class changes.
864 =head2 resultset_class
866 Set the class of the resultset, this is useful if you want to create your
867 own resultset methods. Create your own class derived from
868 L<DBIx::Class::ResultSet>, and set it here.
870 =head2 resultset_attributes
872 Specify here any attributes you wish to pass to your specialised resultset.
878 $self->throw_exception(
879 'resultset does not take any arguments. If you want another resultset, '.
880 'call it on the schema instead.'
882 return $self->{_resultset}
883 if ref $self->{_resultset} eq $self->resultset_class;
884 return $self->{_resultset} = $self->resultset_class->new(
885 $self, $self->{resultset_attributes}
893 =item Arguments: $source_name
897 Set the name of the result source when it is loaded into a schema.
898 This is usefull if you want to refer to a result source by a name other than
901 package ArchivedBooks;
902 use base qw/DBIx::Class/;
903 __PACKAGE__->table('books_archive');
904 __PACKAGE__->source_name('Books');
906 # from your schema...
907 $schema->resultset('Books')->find(1);
909 =head2 throw_exception
911 See L<DBIx::Class::Schema/"throw_exception">.
915 sub throw_exception {
917 if (defined $self->schema) {
918 $self->schema->throw_exception(@_);
926 Matt S. Trout <mst@shadowcatsystems.co.uk>
930 You may distribute this code under the same terms as Perl itself.