use Scalar::Util qw/weaken blessed/;
use Try::Tiny;
+use DBIx::Class::_Util 'UNRESOLVABLE_CONDITION';
use namespace::clean;
=head1 NAME
=over 4
-=item Arguments: 'relname', 'Foreign::Class', $condition, $attrs
+=item Arguments: $rel_name, $foreign_class, $condition, $attrs
=back
- __PACKAGE__->add_relationship('relname',
+ __PACKAGE__->add_relationship('rel_name',
'Foreign::Class',
$condition, $attrs);
clause of the C<JOIN> statement associated with this relationship.
While every coderef-based condition must return a valid C<ON> clause, it may
-elect to additionally return a simplified join-free condition hashref when
-invoked as C<< $result->relationship >>, as opposed to
-C<< $rs->related_resultset('relationship') >>. In this case C<$result> is
-passed to the coderef as C<< $args->{self_rowobj} >>, so a user can do the
-following:
+elect to additionally return a simplified B<optional> join-free condition
+consisting of a hashref with B<all keys being fully qualified names of columns
+declared on the corresponding result source>. This boils down to two scenarios:
+
+=over
+
+=item *
+
+When relationship resolution is invoked after C<< $result->$rel_name >>, as
+opposed to C<< $rs->related_resultset($rel_name) >>, the C<$result> object
+is passed to the coderef as C<< $args->{self_result_object} >>.
+
+=item *
+
+Alternatively when the user-space invokes resolution via
+C<< $result->set_from_related( $rel_name => $foreign_values_or_object ) >>, the
+corresponding data is passed to the coderef as C<< $args->{foreign_values} >>,
+B<always> in the form of a hashref. If a foreign result object is supplied
+(which is valid usage of L</set_from_related>), its values will be extracted
+into hashref form by calling L<get_columns|DBIx::Class::Row/get_columns>.
+
+=back
+
+Note that the above scenarios are mutually exclusive, that is you will be supplied
+none or only one of C<self_result_object> and C<foreign_values>. In other words if
+you define your condition coderef as:
sub {
my $args = shift;
"$args->{foreign_alias}.artist" => { -ident => "$args->{self_alias}.artistid" },
"$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" },
},
- $args->{self_rowobj} && {
- "$args->{foreign_alias}.artist" => $args->{self_rowobj}->artistid,
+ ! $args->{self_result_object} ? () : {
+ "$args->{foreign_alias}.artist" => $args->{self_result_object}->artistid,
"$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" },
},
+ ! $args->{foreign_values} ? () : {
+ "$args->{self_alias}.artistid" => $args->{foreign_values}{artist},
+ }
);
}
-Now this code:
+Then this code:
my $artist = $schema->resultset("Artist")->find({ id => 4 });
$artist->cds_80s->all;
'4', '1990', '1979'
-Note that in order to be able to use
-L<< $result->create_related|DBIx::Class::Relationship::Base/create_related >>,
-the coderef must not only return as its second such a "simple" condition
-hashref which does not depend on joins being available, but the hashref must
-contain only plain values/deflatable objects, such that the result can be
-passed directly to L<DBIx::Class::Relationship::Base/set_from_related>. For
-instance the C<year> constraint in the above example prevents the relationship
-from being used to create related objects (an exception will be thrown).
+While this code:
+
+ my $cd = $schema->resultset("CD")->search({ artist => 1 }, { rows => 1 })->single;
+ my $artist = $schema->resultset("Artist")->new({});
+ $artist->set_from_related('cds_80s');
+
+Will properly set the C<< $artist->artistid >> field of this new object to C<1>
+
+Note that in order to be able to use L</set_from_related> (and by extension
+L<< $result->create_related|DBIx::Class::Relationship::Base/create_related >>),
+the returned join free condition B<must> contain only plain values/deflatable
+objects. For instance the C<year> constraint in the above example prevents
+the relationship from being used to create related objects using
+C<< $artst->create_related( cds_80s => { title => 'blah' } ) >> (an
+exception will be thrown).
In order to allow the user to go truly crazy when generating a custom C<ON>
clause, the C<$args> hashref passed to the subroutine contains some extra
metadata. Currently the supplied coderef is executed as:
$relationship_info->{cond}->({
- self_alias => The alias of the invoking resultset ('me' in case of a result object),
- foreign_alias => The alias of the to-be-joined resultset (often matches relname),
- self_resultsource => The invocant's resultsource,
- foreign_relname => The relationship name (does *not* always match foreign_alias),
- self_rowobj => The invocant itself in case of a $result_object->$relationship call
+ self_resultsource => The resultsource instance on which rel_name is registered
+ rel_name => The relationship name (does *NOT* always match foreign_alias)
+
+ self_alias => The alias of the invoking resultset
+ foreign_alias => The alias of the to-be-joined resultset (does *NOT* always match rel_name)
+
+ # only one of these (or none at all) will ever be supplied to aid in the
+ # construction of a join-free condition
+
+ self_result_object => The invocant *object* itself in case of a call like
+ $result_object->$rel_name( ... )
+
+ foreign_values => A *hashref* of related data: may be passed in directly or
+ derived via ->get_columns() from a related object in case of
+ $result_object->set_from_related( $rel_name, $foreign_result_object )
+
+ # deprecated inconsistent names, will be forever available for legacy code
+ self_rowobj => Old deprecated slot for self_result_object
+ foreign_relname => Old deprecated slot for rel_name
});
=head3 attributes
For a 'belongs_to relationship, note the 'cascade_update':
- MyApp::Schema::Track->belongs_to( cd => 'DBICTest::Schema::CD', 'cd,
+ MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd,
{ proxy => ['title'], cascade_update => 1 }
);
$track->title('New Title');
A hashref where each key is the accessor you want installed in the main class,
and its value is the name of the original in the foreign class.
- MyApp::Schema::Track->belongs_to( cd => 'DBICTest::Schema::CD', 'cd', {
+ MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', {
proxy => { cd_title => 'title' },
});
NOTE: you can pass a nested struct too, for example:
- MyApp::Schema::Track->belongs_to( cd => 'DBICTest::Schema::CD', 'cd', {
+ MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', {
proxy => [ 'year', { cd_title => 'title' } ],
});
The C<belongs_to> relationship does not update across relationships
by default, so if you have a 'proxy' attribute on a belongs_to and want to
-use 'update' on it, you muse set C<< cascade_update => 1 >>.
+use 'update' on it, you must set C<< cascade_update => 1 >>.
This is not a RDMS style cascade update - it purely means that when
an object has update called on it, all the related objects also
return $self->{related_resultsets}{$rel} = do {
- my $rel_info = $self->relationship_info($rel)
+ my $rsrc = $self->result_source;
+
+ my $rel_info = $rsrc->relationship_info($rel)
or $self->throw_exception( "No such relationship '$rel'" );
my $attrs = (@_ > 1 && ref $_[$#_] eq 'HASH' ? pop(@_) : {});
if (@_ > 1 && (@_ % 2 == 1));
my $query = ((@_ > 1) ? {@_} : shift);
- my $rsrc = $self->result_source;
-
# condition resolution may fail if an incomplete master-object prefetch
# is encountered - that is ok during prefetch construction (not yet in_storage)
my ($cond, $is_crosstable) = try {
$rsrc->_resolve_condition( $rel_info->{cond}, $rel, $self, $rel )
}
catch {
- if ($self->in_storage) {
- $self->throw_exception ($_);
- }
-
- $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION; # RV
+ $self->throw_exception ($_) if $self->in_storage;
+ UNRESOLVABLE_CONDITION; # RV, no return()
};
# keep in mind that the following if() block is part of a do{} - no return()s!!!
- if ($is_crosstable) {
- $self->throw_exception (
- "A cross-table relationship condition returned for statically declared '$rel'"
- ) unless ref $rel_info->{cond} eq 'CODE';
-
- # A WHOREIFFIC hack to reinvoke the entire condition resolution
- # with the correct alias. Another way of doing this involves a
- # lot of state passing around, and the @_ positions are already
- # mapped out, making this crap a less icky option.
- #
- # The point of this exercise is to retain the spirit of the original
- # $obj->search_related($rel) where the resulting rset will have the
- # root alias as 'me', instead of $rel (as opposed to invoking
- # $rs->search_related)
-
- local $rsrc->{_relationships}{me} = $rsrc->{_relationships}{$rel}; # make the fake 'me' rel
- my $obj_table_alias = lc($rsrc->source_name) . '__row';
- $obj_table_alias =~ s/\W+/_/g;
-
- $rsrc->resultset->search(
- $self->ident_condition($obj_table_alias),
- { alias => $obj_table_alias },
- )->search_related('me', $query, $attrs)
- }
- else {
- # FIXME - this conditional doesn't seem correct - got to figure out
- # at some point what it does. Also the entire UNRESOLVABLE_CONDITION
- # business seems shady - we could simply not query *at all*
- if ($cond eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) {
- my $reverse = $rsrc->reverse_relationship_info($rel);
- foreach my $rev_rel (keys %$reverse) {
- if ($reverse->{$rev_rel}{attrs}{accessor} && $reverse->{$rev_rel}{attrs}{accessor} eq 'multi') {
- weaken($attrs->{related_objects}{$rev_rel}[0] = $self);
- } else {
- weaken($attrs->{related_objects}{$rev_rel} = $self);
+ my $rs = do {
+ if ($is_crosstable and ref $rel_info->{cond} eq 'CODE') {
+
+ # A WHOREIFFIC hack to reinvoke the entire condition resolution
+ # with the correct alias. Another way of doing this involves a
+ # lot of state passing around, and the @_ positions are already
+ # mapped out, making this crap a less icky option.
+ #
+ # The point of this exercise is to retain the spirit of the original
+ # $obj->search_related($rel) where the resulting rset will have the
+ # root alias as 'me', instead of $rel (as opposed to invoking
+ # $rs->search_related)
+
+ # make the fake 'me' rel
+ local $rsrc->{_relationships}{me} = {
+ %{ $rsrc->{_relationships}{$rel} },
+ _original_name => $rel,
+ };
+
+ my $obj_table_alias = lc($rsrc->source_name) . '__row';
+ $obj_table_alias =~ s/\W+/_/g;
+
+ $rsrc->resultset->search(
+ $self->ident_condition($obj_table_alias),
+ { alias => $obj_table_alias },
+ )->search_related('me', $query, $attrs)
+ }
+ else {
+ # FIXME - this conditional doesn't seem correct - got to figure out
+ # at some point what it does. Also the entire UNRESOLVABLE_CONDITION
+ # business seems shady - we could simply not query *at all*
+ if ($cond eq UNRESOLVABLE_CONDITION) {
+ my $reverse = $rsrc->reverse_relationship_info($rel);
+ foreach my $rev_rel (keys %$reverse) {
+ if ($reverse->{$rev_rel}{attrs}{accessor} && $reverse->{$rev_rel}{attrs}{accessor} eq 'multi') {
+ weaken($attrs->{related_objects}{$rev_rel}[0] = $self);
+ } else {
+ weaken($attrs->{related_objects}{$rev_rel} = $self);
+ }
}
}
- }
- elsif (ref $cond eq 'ARRAY') {
- $cond = [ map {
- if (ref $_ eq 'HASH') {
- my $hash;
- foreach my $key (keys %$_) {
- my $newkey = $key !~ /\./ ? "me.$key" : $key;
- $hash->{$newkey} = $_->{$key};
+ elsif (ref $cond eq 'ARRAY') {
+ $cond = [ map {
+ if (ref $_ eq 'HASH') {
+ my $hash;
+ foreach my $key (keys %$_) {
+ my $newkey = $key !~ /\./ ? "me.$key" : $key;
+ $hash->{$newkey} = $_->{$key};
+ }
+ $hash;
+ } else {
+ $_;
}
- $hash;
- } else {
- $_;
+ } @$cond ];
+ }
+ elsif (ref $cond eq 'HASH') {
+ foreach my $key (grep { ! /\./ } keys %$cond) {
+ $cond->{"me.$key"} = delete $cond->{$key};
}
- } @$cond ];
- }
- elsif (ref $cond eq 'HASH') {
- foreach my $key (grep { ! /\./ } keys %$cond) {
- $cond->{"me.$key"} = delete $cond->{$key};
}
- }
- $query = ($query ? { '-and' => [ $cond, $query ] } : $cond);
- $rsrc->related_source($rel)->resultset->search(
- $query, $attrs
- );
+ $query = ($query ? { '-and' => [ $cond, $query ] } : $cond);
+ $rsrc->related_source($rel)->resultset->search(
+ $query, $attrs
+ );
+ }
+ };
+ if (
+ $rel_info->{attrs}{accessor} eq 'single'
+ and
+ exists $self->{_relationship_data}{$rel}
+ ) {
+ $rs->set_cache([ $self->{_relationship_data}{$rel} || () ]);
}
+ elsif (
+ $rel_info->{attrs}{accessor} eq 'filter'
+ and
+ exists $self->{_filter_relationship_data}{$rel}
+ ) {
+ $rs->set_cache([ $self->{_filter_relationship_data}{$rel} || () ]);
+ }
+ $rs;
};
}
=cut
sub new_related {
- my ($self, $rel, $values) = @_;
-
- # FIXME - this is a bad position for this (also an identical copy in
- # set_from_related), but I have no saner way to hook, and I absolutely
- # want this to throw at least for coderefs, instead of the "insert a NULL
- # when it gets hard" insanity --ribasushi
- #
- # sanity check - currently throw when a complex coderef rel is encountered
- # FIXME - should THROW MOAR!
-
- if (ref $self) { # cdbi calls this as a class method, /me vomits
-
- my $rsrc = $self->result_source;
- my $rel_info = $rsrc->relationship_info($rel)
- or $self->throw_exception( "No such relationship '$rel'" );
- my (undef, $crosstable, $cond_targets) = $rsrc->_resolve_condition (
- $rel_info->{cond}, $rel, $self, $rel
- );
-
- $self->throw_exception("Custom relationship '$rel' does not resolve to a join-free condition fragment")
- if $crosstable;
-
- if (my @unspecified_rel_condition_chunks = grep { ! exists $values->{$_} } @{$cond_targets||[]} ) {
- $self->throw_exception(sprintf (
- "Custom relationship '%s' not definitive - returns conditions instead of values for column(s): %s",
- $rel,
- map { "'$_'" } @unspecified_rel_condition_chunks
- ));
- }
- }
-
- return $self->search_related($rel)->new_result($values);
+ my ($self, $rel, $data) = @_;
+
+ return $self->search_related($rel)->new_result( $self->result_source->_resolve_relationship_condition (
+ infer_values_based_on => $data,
+ rel_name => $rel,
+ self_result_object => $self,
+ foreign_alias => $rel,
+ self_alias => 'me',
+ )->{inferred_values} );
}
=head2 create_related
This is called internally when you pass existing objects as values to
L<DBIx::Class::ResultSet/create>, or pass an object to a belongs_to accessor.
-The columns are only set in the local copy of the object, call L</update> to
-set them in the storage.
+The columns are only set in the local copy of the object, call
+L<update|DBIx::Class::Row/update> to update them in the storage.
=cut
sub set_from_related {
my ($self, $rel, $f_obj) = @_;
- my $rsrc = $self->result_source;
- my $rel_info = $rsrc->relationship_info($rel)
- or $self->throw_exception( "No such relationship '$rel'" );
-
- if (defined $f_obj) {
- my $f_class = $rel_info->{class};
- $self->throw_exception( "Object '$f_obj' isn't a ".$f_class )
- unless blessed $f_obj and $f_obj->isa($f_class);
- }
-
-
- # FIXME - this is a bad position for this (also an identical copy in
- # new_related), but I have no saner way to hook, and I absolutely
- # want this to throw at least for coderefs, instead of the "insert a NULL
- # when it gets hard" insanity --ribasushi
- #
- # sanity check - currently throw when a complex coderef rel is encountered
- # FIXME - should THROW MOAR!
- my ($cond, $crosstable, $cond_targets) = $rsrc->_resolve_condition (
- $rel_info->{cond}, $f_obj, $rel, $rel
- );
- $self->throw_exception("Custom relationship '$rel' does not resolve to a join-free condition fragment")
- if $crosstable;
- $self->throw_exception(sprintf (
- "Custom relationship '%s' not definitive - returns conditions instead of values for column(s): %s",
- $rel,
- map { "'$_'" } @$cond_targets
- )) if $cond_targets;
-
- $self->set_columns($cond);
+ $self->set_columns( $self->result_source->_resolve_relationship_condition (
+ infer_values_based_on => {},
+ rel_name => $rel,
+ foreign_values => $f_obj,
+ foreign_alias => $rel,
+ self_alias => 'me',
+ )->{inferred_values} );
return 1;
}
the related object itself won't be deleted unless you call ->delete() on
it. This method just removes the link between the two objects.
-=head1 AUTHOR AND CONTRIBUTORS
+=head1 FURTHER QUESTIONS?
-See L<AUTHOR|DBIx::Class/AUTHOR> and L<CONTRIBUTORS|DBIx::Class/CONTRIBUTORS> in DBIx::Class
+Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>.
-=head1 LICENSE
+=head1 COPYRIGHT AND LICENSE
-You may distribute this code under the same terms as Perl itself.
+This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE>
+by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can
+redistribute it and/or modify it under the same terms as the
+L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>.
=cut
projects / dbsrgits/DBIx-Class.git / blobdiff