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}++;
180 # eval for the case of storage without table
181 eval { $info = $self->storage->columns_info_for( $self->from, keys %{$self->_columns} ) };
183 for my $realcol ( keys %{$info} ) {
184 $lc_info->{lc $realcol} = $info->{$realcol};
186 foreach my $col ( keys %{$self->_columns} ) {
187 $self->_columns->{$col} = $info->{$col} || $lc_info->{lc $col};
191 return $self->_columns->{$column};
196 my @column_names = $obj->columns;
198 Returns all column names in the order they were declared to add_columns.
204 $self->throw_exception(
205 "columns() is a read-only accessor, did you mean add_columns()?"
207 return @{$self->{_ordered_columns}||[]};
210 =head2 remove_columns
212 $table->remove_columns(qw/col1 col2 col3/);
214 Removes columns from the result source.
218 $table->remove_column('col');
220 Convenience alias to remove_columns.
225 my ($self, @cols) = @_;
227 return unless $self->_ordered_columns;
229 my $columns = $self->_columns;
232 foreach my $col (@{$self->_ordered_columns}) {
233 push @remaining, $col unless grep(/$col/, @cols);
237 undef $columns->{$_};
240 $self->_ordered_columns(\@remaining);
243 *remove_column = \&remove_columns;
245 =head2 set_primary_key
249 =item Arguments: @cols
253 Defines one or more columns as primary key for this source. Should be
254 called after C<add_columns>.
256 Additionally, defines a unique constraint named C<primary>.
258 The primary key columns are used by L<DBIx::Class::PK::Auto> to
259 retrieve automatically created values from the database.
263 sub set_primary_key {
264 my ($self, @cols) = @_;
265 # check if primary key columns are valid columns
266 foreach my $col (@cols) {
267 $self->throw_exception("No such column $col on table " . $self->name)
268 unless $self->has_column($col);
270 $self->_primaries(\@cols);
272 $self->add_unique_constraint(primary => \@cols);
275 =head2 primary_columns
277 Read-only accessor which returns the list of primary keys.
281 sub primary_columns {
282 return @{shift->_primaries||[]};
285 =head2 add_unique_constraint
287 Declare a unique constraint on this source. Call once for each unique
290 # For UNIQUE (column1, column2)
291 __PACKAGE__->add_unique_constraint(
292 constraint_name => [ qw/column1 column2/ ],
295 Unique constraints are used, for example, when you call
296 L<DBIx::Class::ResultSet/find>. Only columns in the constraint are searched.
300 sub add_unique_constraint {
301 my ($self, $name, $cols) = @_;
303 foreach my $col (@$cols) {
304 $self->throw_exception("No such column $col on table " . $self->name)
305 unless $self->has_column($col);
308 my %unique_constraints = $self->unique_constraints;
309 $unique_constraints{$name} = $cols;
310 $self->_unique_constraints(\%unique_constraints);
313 =head2 unique_constraints
315 Read-only accessor which returns the list of unique constraints on this source.
319 sub unique_constraints {
320 return %{shift->_unique_constraints||{}};
323 =head2 unique_constraint_names
325 Returns the list of unique constraint names defined on this source.
329 sub unique_constraint_names {
332 my %unique_constraints = $self->unique_constraints;
334 return keys %unique_constraints;
337 =head2 unique_constraint_columns
339 Returns the list of columns that make up the specified unique constraint.
343 sub unique_constraint_columns {
344 my ($self, $constraint_name) = @_;
346 my %unique_constraints = $self->unique_constraints;
348 $self->throw_exception(
349 "Unknown unique constraint $constraint_name on '" . $self->name . "'"
350 ) unless exists $unique_constraints{$constraint_name};
352 return @{ $unique_constraints{$constraint_name} };
357 Returns an expression of the source to be supplied to storage to specify
358 retrieval from this source. In the case of a database, the required FROM
363 Returns the L<DBIx::Class::Schema> object that this result source
368 Returns the storage handle for the current schema.
370 See also: L<DBIx::Class::Storage>
374 sub storage { shift->schema->storage; }
376 =head2 add_relationship
378 $source->add_relationship('relname', 'related_source', $cond, $attrs);
380 The relationship name can be arbitrary, but must be unique for each
381 relationship attached to this result source. 'related_source' should
382 be the name with which the related result source was registered with
383 the current schema. For example:
385 $schema->source('Book')->add_relationship('reviews', 'Review', {
386 'foreign.book_id' => 'self.id',
389 The condition C<$cond> needs to be an L<SQL::Abstract>-style
390 representation of the join between the tables. For example, if you're
391 creating a rel from Author to Book,
393 { 'foreign.author_id' => 'self.id' }
395 will result in the JOIN clause
397 author me JOIN book foreign ON foreign.author_id = me.id
399 You can specify as many foreign => self mappings as necessary.
401 Valid attributes are as follows:
407 Explicitly specifies the type of join to use in the relationship. Any
408 SQL join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in
409 the SQL command immediately before C<JOIN>.
413 An arrayref containing a list of accessors in the foreign class to proxy in
414 the main class. If, for example, you do the following:
416 CD->might_have(liner_notes => 'LinerNotes', undef, {
417 proxy => [ qw/notes/ ],
420 Then, assuming LinerNotes has an accessor named notes, you can do:
422 my $cd = CD->find(1);
423 # set notes -- LinerNotes object is created if it doesn't exist
424 $cd->notes('Notes go here');
428 Specifies the type of accessor that should be created for the
429 relationship. Valid values are C<single> (for when there is only a single
430 related object), C<multi> (when there can be many), and C<filter> (for
431 when there is a single related object, but you also want the relationship
432 accessor to double as a column accessor). For C<multi> accessors, an
433 add_to_* method is also created, which calls C<create_related> for the
440 sub add_relationship {
441 my ($self, $rel, $f_source_name, $cond, $attrs) = @_;
442 $self->throw_exception("Can't create relationship without join condition")
446 my %rels = %{ $self->_relationships };
447 $rels{$rel} = { class => $f_source_name,
448 source => $f_source_name,
451 $self->_relationships(\%rels);
455 # XXX disabled. doesn't work properly currently. skip in tests.
457 my $f_source = $self->schema->source($f_source_name);
459 $self->ensure_class_loaded($f_source_name);
460 $f_source = $f_source_name->result_source;
461 #my $s_class = ref($self->schema);
462 #$f_source_name =~ m/^${s_class}::(.*)$/;
463 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
464 #$f_source = $self->schema->source($f_source_name);
466 return unless $f_source; # Can't test rel without f_source
468 eval { $self->resolve_join($rel, 'me') };
470 if ($@) { # If the resolve failed, back out and re-throw the error
471 delete $rels{$rel}; #
472 $self->_relationships(\%rels);
473 $self->throw_exception("Error creating relationship $rel: $@");
480 Returns all relationship names for this source.
485 return keys %{shift->_relationships};
488 =head2 relationship_info
492 =item Arguments: $relname
496 Returns a hash of relationship information for the specified relationship
501 sub relationship_info {
502 my ($self, $rel) = @_;
503 return $self->_relationships->{$rel};
506 =head2 has_relationship
510 =item Arguments: $rel
514 Returns true if the source has a relationship of this name, false otherwise.
518 sub has_relationship {
519 my ($self, $rel) = @_;
520 return exists $self->_relationships->{$rel};
523 =head2 reverse_relationship_info
527 =item Arguments: $relname
531 Returns an array of hash references of relationship information for
532 the other side of the specified relationship name.
536 sub reverse_relationship_info {
537 my ($self, $rel) = @_;
538 my $rel_info = $self->relationship_info($rel);
541 return $ret unless ((ref $rel_info->{cond}) eq 'HASH');
543 my @cond = keys(%{$rel_info->{cond}});
544 my @refkeys = map {/^\w+\.(\w+)$/} @cond;
545 my @keys = map {$rel_info->{cond}->{$_} =~ /^\w+\.(\w+)$/} @cond;
547 # Get the related result source for this relationship
548 my $othertable = $self->related_source($rel);
550 # Get all the relationships for that source that related to this source
551 # whose foreign column set are our self columns on $rel and whose self
552 # columns are our foreign columns on $rel.
553 my @otherrels = $othertable->relationships();
554 my $otherrelationship;
555 foreach my $otherrel (@otherrels) {
556 my $otherrel_info = $othertable->relationship_info($otherrel);
558 my $back = $othertable->related_source($otherrel);
559 next unless $back->name eq $self->name;
563 if (ref $otherrel_info->{cond} eq 'HASH') {
564 @othertestconds = ($otherrel_info->{cond});
566 elsif (ref $otherrel_info->{cond} eq 'ARRAY') {
567 @othertestconds = @{$otherrel_info->{cond}};
573 foreach my $othercond (@othertestconds) {
574 my @other_cond = keys(%$othercond);
575 my @other_refkeys = map {/^\w+\.(\w+)$/} @other_cond;
576 my @other_keys = map {$othercond->{$_} =~ /^\w+\.(\w+)$/} @other_cond;
577 next if (!$self->compare_relationship_keys(\@refkeys, \@other_keys) ||
578 !$self->compare_relationship_keys(\@other_refkeys, \@keys));
579 $ret->{$otherrel} = $otherrel_info;
585 =head2 compare_relationship_keys
589 =item Arguments: $keys1, $keys2
593 Returns true if both sets of keynames are the same, false otherwise.
597 sub compare_relationship_keys {
598 my ($self, $keys1, $keys2) = @_;
600 # Make sure every keys1 is in keys2
602 foreach my $key (@$keys1) {
604 foreach my $prim (@$keys2) {
613 # Make sure every key2 is in key1
615 foreach my $prim (@$keys2) {
617 foreach my $key (@$keys1) {
634 =item Arguments: $relation
638 Returns the join structure required for the related result source.
643 my ($self, $join, $alias, $seen) = @_;
645 if (ref $join eq 'ARRAY') {
646 return map { $self->resolve_join($_, $alias, $seen) } @$join;
647 } elsif (ref $join eq 'HASH') {
650 my $as = ($seen->{$_} ? $_.'_'.($seen->{$_}+1) : $_);
651 ($self->resolve_join($_, $alias, $seen),
652 $self->related_source($_)->resolve_join($join->{$_}, $as, $seen));
654 } elsif (ref $join) {
655 $self->throw_exception("No idea how to resolve join reftype ".ref $join);
657 my $count = ++$seen->{$join};
658 #use Data::Dumper; warn Dumper($seen);
659 my $as = ($count > 1 ? "${join}_${count}" : $join);
660 my $rel_info = $self->relationship_info($join);
661 $self->throw_exception("No such relationship ${join}") unless $rel_info;
662 my $type = $rel_info->{attrs}{join_type} || '';
663 return [ { $as => $self->related_source($join)->from,
664 -join_type => $type },
665 $self->resolve_condition($rel_info->{cond}, $as, $alias) ];
669 =head2 resolve_condition
673 =item Arguments: $cond, $as, $alias|$object
677 Resolves the passed condition to a concrete query fragment. If given an alias,
678 returns a join condition; if given an object, inverts that object to produce
679 a related conditional from that object.
683 sub resolve_condition {
684 my ($self, $cond, $as, $for) = @_;
686 if (ref $cond eq 'HASH') {
688 foreach my $k (keys %{$cond}) {
690 # XXX should probably check these are valid columns
691 $k =~ s/^foreign\.// ||
692 $self->throw_exception("Invalid rel cond key ${k}");
694 $self->throw_exception("Invalid rel cond val ${v}");
695 if (ref $for) { # Object
696 #warn "$self $k $for $v";
697 $ret{$k} = $for->get_column($v);
699 } elsif (!defined $for) { # undef, i.e. "no object"
701 } elsif (ref $as) { # reverse object
702 $ret{$v} = $as->get_column($k);
703 } elsif (!defined $as) { # undef, i.e. "no reverse object"
706 $ret{"${as}.${k}"} = "${for}.${v}";
710 } elsif (ref $cond eq 'ARRAY') {
711 return [ map { $self->resolve_condition($_, $as, $for) } @$cond ];
713 die("Can't handle this yet :(");
717 =head2 resolve_prefetch
721 =item Arguments: hashref/arrayref/scalar
725 Accepts one or more relationships for the current source and returns an
726 array of column names for each of those relationships. Column names are
727 prefixed relative to the current source, in accordance with where they appear
728 in the supplied relationships. Examples:
730 my $source = $schema->resultset('Tag')->source;
731 @columns = $source->resolve_prefetch( { cd => 'artist' } );
739 # 'cd.artist.artistid',
743 @columns = $source->resolve_prefetch( qw[/ cd /] );
753 $source = $schema->resultset('CD')->source;
754 @columns = $source->resolve_prefetch( qw[/ artist producer /] );
760 # 'producer.producerid',
766 sub resolve_prefetch {
767 my ($self, $pre, $alias, $seen, $order, $collapse) = @_;
769 #$alias ||= $self->name;
770 #warn $alias, Dumper $pre;
771 if( ref $pre eq 'ARRAY' ) {
773 map { $self->resolve_prefetch( $_, $alias, $seen, $order, $collapse ) }
776 elsif( ref $pre eq 'HASH' ) {
779 $self->resolve_prefetch($_, $alias, $seen, $order, $collapse),
780 $self->related_source($_)->resolve_prefetch(
781 $pre->{$_}, "${alias}.$_", $seen, $order, $collapse)
787 $self->throw_exception(
788 "don't know how to resolve prefetch reftype ".ref($pre));
791 my $count = ++$seen->{$pre};
792 my $as = ($count > 1 ? "${pre}_${count}" : $pre);
793 my $rel_info = $self->relationship_info( $pre );
794 $self->throw_exception( $self->name . " has no such relationship '$pre'" )
796 my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
797 my $rel_source = $self->related_source($pre);
799 if (exists $rel_info->{attrs}{accessor}
800 && $rel_info->{attrs}{accessor} eq 'multi') {
801 $self->throw_exception(
802 "Can't prefetch has_many ${pre} (join cond too complex)")
803 unless ref($rel_info->{cond}) eq 'HASH';
804 my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
805 keys %{$rel_info->{cond}};
806 $collapse->{"${as_prefix}${pre}"} = \@key;
807 my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY'
808 ? @{$rel_info->{attrs}{order_by}}
809 : (defined $rel_info->{attrs}{order_by}
810 ? ($rel_info->{attrs}{order_by})
812 push(@$order, map { "${as}.$_" } (@key, @ord));
815 return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
816 $rel_source->columns;
817 #warn $alias, Dumper (\@ret);
822 =head2 related_source
826 =item Arguments: $relname
830 Returns the result source object for the given relationship.
835 my ($self, $rel) = @_;
836 if( !$self->has_relationship( $rel ) ) {
837 $self->throw_exception("No such relationship '$rel'");
839 return $self->schema->source($self->relationship_info($rel)->{source});
846 =item Arguments: $relname
850 Returns the class name for objects in the given relationship.
855 my ($self, $rel) = @_;
856 if( !$self->has_relationship( $rel ) ) {
857 $self->throw_exception("No such relationship '$rel'");
859 return $self->schema->class($self->relationship_info($rel)->{source});
864 Returns a resultset for the given source. This will initially be created
867 $self->resultset_class->new($self, $self->resultset_attributes)
869 but is cached from then on unless resultset_class changes.
871 =head2 resultset_class
873 Set the class of the resultset, this is useful if you want to create your
874 own resultset methods. Create your own class derived from
875 L<DBIx::Class::ResultSet>, and set it here.
877 =head2 resultset_attributes
879 Specify here any attributes you wish to pass to your specialised resultset.
885 $self->throw_exception(
886 'resultset does not take any arguments. If you want another resultset, '.
887 'call it on the schema instead.'
890 # disabled until we can figure out a way to do it without consistency issues
892 #return $self->{_resultset}
893 # if ref $self->{_resultset} eq $self->resultset_class;
894 #return $self->{_resultset} =
896 return $self->resultset_class->new(
897 $self, $self->{resultset_attributes}
905 =item Arguments: $source_name
909 Set the name of the result source when it is loaded into a schema.
910 This is usefull if you want to refer to a result source by a name other than
913 package ArchivedBooks;
914 use base qw/DBIx::Class/;
915 __PACKAGE__->table('books_archive');
916 __PACKAGE__->source_name('Books');
918 # from your schema...
919 $schema->resultset('Books')->find(1);
921 =head2 throw_exception
923 See L<DBIx::Class::Schema/"throw_exception">.
927 sub throw_exception {
929 if (defined $self->schema) {
930 $self->schema->throw_exception(@_);
938 Matt S. Trout <mst@shadowcatsystems.co.uk>
942 You may distribute this code under the same terms as Perl itself.