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 eval "require $f_source_name;";
461 die $@ unless $@ =~ /Can't locate/;
463 $f_source = $f_source_name->result_source;
464 #my $s_class = ref($self->schema);
465 #$f_source_name =~ m/^${s_class}::(.*)$/;
466 #$self->schema->register_class(($1 || $f_source_name), $f_source_name);
467 #$f_source = $self->schema->source($f_source_name);
469 return unless $f_source; # Can't test rel without f_source
471 eval { $self->resolve_join($rel, 'me') };
473 if ($@) { # If the resolve failed, back out and re-throw the error
474 delete $rels{$rel}; #
475 $self->_relationships(\%rels);
476 $self->throw_exception("Error creating relationship $rel: $@");
483 Returns all relationship names for this source.
488 return keys %{shift->_relationships};
491 =head2 relationship_info
495 =item Arguments: $relname
499 Returns a hash of relationship information for the specified relationship
504 sub relationship_info {
505 my ($self, $rel) = @_;
506 return $self->_relationships->{$rel};
509 =head2 has_relationship
513 =item Arguments: $rel
517 Returns true if the source has a relationship of this name, false otherwise.
521 sub has_relationship {
522 my ($self, $rel) = @_;
523 return exists $self->_relationships->{$rel};
526 =head2 reverse_relationship_info
530 =item Arguments: $relname
534 Returns an array of hash references of relationship information for
535 the other side of the specified relationship name.
539 sub reverse_relationship_info {
540 my ($self, $rel) = @_;
541 my $rel_info = $self->relationship_info($rel);
544 return $ret unless ((ref $rel_info->{cond}) eq 'HASH');
546 my @cond = keys(%{$rel_info->{cond}});
547 my @refkeys = map {/^\w+\.(\w+)$/} @cond;
548 my @keys = map {$rel_info->{cond}->{$_} =~ /^\w+\.(\w+)$/} @cond;
550 # Get the related result source for this relationship
551 my $othertable = $self->related_source($rel);
553 # Get all the relationships for that source that related to this source
554 # whose foreign column set are our self columns on $rel and whose self
555 # columns are our foreign columns on $rel.
556 my @otherrels = $othertable->relationships();
557 my $otherrelationship;
558 foreach my $otherrel (@otherrels) {
559 my $otherrel_info = $othertable->relationship_info($otherrel);
561 my $back = $othertable->related_source($otherrel);
562 next unless $back->name eq $self->name;
566 if (ref $otherrel_info->{cond} eq 'HASH') {
567 @othertestconds = ($otherrel_info->{cond});
569 elsif (ref $otherrel_info->{cond} eq 'ARRAY') {
570 @othertestconds = @{$otherrel_info->{cond}};
576 foreach my $othercond (@othertestconds) {
577 my @other_cond = keys(%$othercond);
578 my @other_refkeys = map {/^\w+\.(\w+)$/} @other_cond;
579 my @other_keys = map {$othercond->{$_} =~ /^\w+\.(\w+)$/} @other_cond;
580 next if (!$self->compare_relationship_keys(\@refkeys, \@other_keys) ||
581 !$self->compare_relationship_keys(\@other_refkeys, \@keys));
582 $ret->{$otherrel} = $otherrel_info;
588 =head2 compare_relationship_keys
592 =item Arguments: $keys1, $keys2
596 Returns true if both sets of keynames are the same, false otherwise.
600 sub compare_relationship_keys {
601 my ($self, $keys1, $keys2) = @_;
603 # Make sure every keys1 is in keys2
605 foreach my $key (@$keys1) {
607 foreach my $prim (@$keys2) {
616 # Make sure every key2 is in key1
618 foreach my $prim (@$keys2) {
620 foreach my $key (@$keys1) {
637 =item Arguments: $relation
641 Returns the join structure required for the related result source.
646 my ($self, $join, $alias, $seen) = @_;
648 if (ref $join eq 'ARRAY') {
649 return map { $self->resolve_join($_, $alias, $seen) } @$join;
650 } elsif (ref $join eq 'HASH') {
653 my $as = ($seen->{$_} ? $_.'_'.($seen->{$_}+1) : $_);
654 ($self->resolve_join($_, $alias, $seen),
655 $self->related_source($_)->resolve_join($join->{$_}, $as, $seen));
657 } elsif (ref $join) {
658 $self->throw_exception("No idea how to resolve join reftype ".ref $join);
660 my $count = ++$seen->{$join};
661 #use Data::Dumper; warn Dumper($seen);
662 my $as = ($count > 1 ? "${join}_${count}" : $join);
663 my $rel_info = $self->relationship_info($join);
664 $self->throw_exception("No such relationship ${join}") unless $rel_info;
665 my $type = $rel_info->{attrs}{join_type} || '';
666 return [ { $as => $self->related_source($join)->from,
667 -join_type => $type },
668 $self->resolve_condition($rel_info->{cond}, $as, $alias) ];
672 =head2 resolve_condition
676 =item Arguments: $cond, $as, $alias|$object
680 Resolves the passed condition to a concrete query fragment. If given an alias,
681 returns a join condition; if given an object, inverts that object to produce
682 a related conditional from that object.
686 sub resolve_condition {
687 my ($self, $cond, $as, $for) = @_;
689 if (ref $cond eq 'HASH') {
691 foreach my $k (keys %{$cond}) {
693 # XXX should probably check these are valid columns
694 $k =~ s/^foreign\.// ||
695 $self->throw_exception("Invalid rel cond key ${k}");
697 $self->throw_exception("Invalid rel cond val ${v}");
698 if (ref $for) { # Object
699 #warn "$self $k $for $v";
700 $ret{$k} = $for->get_column($v);
702 } elsif (!defined $for) { # undef, i.e. "no object"
704 } elsif (ref $as) { # reverse object
705 $ret{$v} = $as->get_column($k);
706 } elsif (!defined $as) { # undef, i.e. "no reverse object"
709 $ret{"${as}.${k}"} = "${for}.${v}";
713 } elsif (ref $cond eq 'ARRAY') {
714 return [ map { $self->resolve_condition($_, $as, $for) } @$cond ];
716 die("Can't handle this yet :(");
720 =head2 resolve_prefetch
724 =item Arguments: hashref/arrayref/scalar
728 Accepts one or more relationships for the current source and returns an
729 array of column names for each of those relationships. Column names are
730 prefixed relative to the current source, in accordance with where they appear
731 in the supplied relationships. Examples:
733 my $source = $schema->resultset('Tag')->source;
734 @columns = $source->resolve_prefetch( { cd => 'artist' } );
742 # 'cd.artist.artistid',
746 @columns = $source->resolve_prefetch( qw[/ cd /] );
756 $source = $schema->resultset('CD')->source;
757 @columns = $source->resolve_prefetch( qw[/ artist producer /] );
763 # 'producer.producerid',
769 sub resolve_prefetch {
770 my ($self, $pre, $alias, $seen, $order, $collapse) = @_;
772 #$alias ||= $self->name;
773 #warn $alias, Dumper $pre;
774 if( ref $pre eq 'ARRAY' ) {
776 map { $self->resolve_prefetch( $_, $alias, $seen, $order, $collapse ) }
779 elsif( ref $pre eq 'HASH' ) {
782 $self->resolve_prefetch($_, $alias, $seen, $order, $collapse),
783 $self->related_source($_)->resolve_prefetch(
784 $pre->{$_}, "${alias}.$_", $seen, $order, $collapse)
790 $self->throw_exception(
791 "don't know how to resolve prefetch reftype ".ref($pre));
794 my $count = ++$seen->{$pre};
795 my $as = ($count > 1 ? "${pre}_${count}" : $pre);
796 my $rel_info = $self->relationship_info( $pre );
797 $self->throw_exception( $self->name . " has no such relationship '$pre'" )
799 my $as_prefix = ($alias =~ /^.*?\.(.+)$/ ? $1.'.' : '');
800 my $rel_source = $self->related_source($pre);
802 if (exists $rel_info->{attrs}{accessor}
803 && $rel_info->{attrs}{accessor} eq 'multi') {
804 $self->throw_exception(
805 "Can't prefetch has_many ${pre} (join cond too complex)")
806 unless ref($rel_info->{cond}) eq 'HASH';
807 my @key = map { (/^foreign\.(.+)$/ ? ($1) : ()); }
808 keys %{$rel_info->{cond}};
809 $collapse->{"${as_prefix}${pre}"} = \@key;
810 my @ord = (ref($rel_info->{attrs}{order_by}) eq 'ARRAY'
811 ? @{$rel_info->{attrs}{order_by}}
812 : (defined $rel_info->{attrs}{order_by}
813 ? ($rel_info->{attrs}{order_by})
815 push(@$order, map { "${as}.$_" } (@key, @ord));
818 return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
819 $rel_source->columns;
820 #warn $alias, Dumper (\@ret);
825 =head2 related_source
829 =item Arguments: $relname
833 Returns the result source object for the given relationship.
838 my ($self, $rel) = @_;
839 if( !$self->has_relationship( $rel ) ) {
840 $self->throw_exception("No such relationship '$rel'");
842 return $self->schema->source($self->relationship_info($rel)->{source});
849 =item Arguments: $relname
853 Returns the class name for objects in the given relationship.
858 my ($self, $rel) = @_;
859 if( !$self->has_relationship( $rel ) ) {
860 $self->throw_exception("No such relationship '$rel'");
862 return $self->schema->class($self->relationship_info($rel)->{source});
867 Returns a resultset for the given source. This will initially be created
870 $self->resultset_class->new($self, $self->resultset_attributes)
872 but is cached from then on unless resultset_class changes.
874 =head2 resultset_class
876 Set the class of the resultset, this is useful if you want to create your
877 own resultset methods. Create your own class derived from
878 L<DBIx::Class::ResultSet>, and set it here.
880 =head2 resultset_attributes
882 Specify here any attributes you wish to pass to your specialised resultset.
888 $self->throw_exception(
889 'resultset does not take any arguments. If you want another resultset, '.
890 'call it on the schema instead.'
893 # disabled until we can figure out a way to do it without consistency issues
895 #return $self->{_resultset}
896 # if ref $self->{_resultset} eq $self->resultset_class;
897 #return $self->{_resultset} =
899 return $self->resultset_class->new(
900 $self, $self->{resultset_attributes}
908 =item Arguments: $source_name
912 Set the name of the result source when it is loaded into a schema.
913 This is usefull if you want to refer to a result source by a name other than
916 package ArchivedBooks;
917 use base qw/DBIx::Class/;
918 __PACKAGE__->table('books_archive');
919 __PACKAGE__->source_name('Books');
921 # from your schema...
922 $schema->resultset('Books')->find(1);
924 =head2 throw_exception
926 See L<DBIx::Class::Schema/"throw_exception">.
930 sub throw_exception {
932 if (defined $self->schema) {
933 $self->schema->throw_exception(@_);
941 Matt S. Trout <mst@shadowcatsystems.co.uk>
945 You may distribute this code under the same terms as Perl itself.