X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship%2FBase.pm;h=5eb565bc1c2f32c11542fdd2a675e3a66ec82ec7;hb=refs%2Fheads%2Fpeople%2Filmari%2Fdelay-related-rs-creation-for-single-rels;hp=a41d6b4df0b1d15874a6df2da4f58f93f087e2de;hpb=a5fc497548f9f980d3fd1deb7b7cb9095d079651;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/Relationship/Base.pm b/lib/DBIx/Class/Relationship/Base.pm index a41d6b4..5eb565b 100644 --- a/lib/DBIx/Class/Relationship/Base.pm +++ b/lib/DBIx/Class/Relationship/Base.pm @@ -7,6 +7,7 @@ use base qw/DBIx::Class/; use Scalar::Util qw/weaken blessed/; use Try::Tiny; +use DBIx::Class::_Util 'UNRESOLVABLE_CONDITION'; use namespace::clean; =head1 NAME @@ -38,11 +39,11 @@ methods, for predefined ones, look in L. =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); @@ -180,11 +181,32 @@ L and the resulting SQL will be used verbatim as the C clause of the C statement associated with this relationship. While every coderef-based condition must return a valid C 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 join-free condition +consisting of a hashref with B. 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 in the form of a hashref. If a foreign result object is supplied +(which is valid usage of L), its values will be extracted +into hashref form by calling L. + +=back + +Note that the above scenarios are mutually exclusive, that is you will be supplied +none or only one of C and C. In other words if +you define your condition coderef as: sub { my $args = shift; @@ -194,14 +216,17 @@ following: "$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; @@ -218,25 +243,46 @@ With the bind values: '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. For -instance the C 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 (and by extension +L<< $result->create_related|DBIx::Class::Relationship::Base/create_related >>), +the returned join free condition B contain only plain values/deflatable +objects. For instance the C constraint in the above example prevents +the relationship from being used to create related objects using +C<< $artst->create_related( cds_80s => { title => 'blah' } ) >> (an +exception will be thrown). In order to allow the user to go truly crazy when generating a custom C clause, the C<$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 @@ -360,7 +406,7 @@ the relationship attributes. The C 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 @@ -465,7 +511,9 @@ sub related_resultset { 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(@_) : {}); @@ -475,85 +523,99 @@ sub related_resultset { 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} || () ]); + } + $rs; }; } @@ -627,38 +689,15 @@ your storage until you call L on it. =cut sub new_related { - my ($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 => $rel, + self_alias => 'me', + )->{inferred_values} ); } =head2 create_related @@ -792,44 +831,21 @@ call set_from_related on the book. This is called internally when you pass existing objects as values to L, or pass an object to a belongs_to accessor. -The columns are only set in the local copy of the object, call L to -set them in the storage. +The columns are only set in the local copy of the object, call +L to update them in the storage. =cut sub set_from_related { my ($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; } @@ -986,13 +1002,16 @@ Removes the link between the current object and the related object. Note that 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 and L in DBIx::Class +Check the list of L. -=head1 LICENSE +=head1 COPYRIGHT AND LICENSE -You may distribute this code under the same terms as Perl itself. +This module is free software L +by the L. You can +redistribute it and/or modify it under the same terms as the +L. =cut