X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship%2FBase.pm;h=c4d111186007278bfaa1cde4acc705f8320d9042;hb=8848b5bd9ece2c0320b99ce616bd6f3ecd205159;hp=b4dc4d2ee3968b503b592e054d36642fbd66fe3c;hpb=5d2588ccdd92a01535fefd77c45240f75e8ec090;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/Relationship/Base.pm b/lib/DBIx/Class/Relationship/Base.pm index b4dc4d2..c4d1111 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 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 @@ -288,7 +334,7 @@ Then, assuming MyApp::Schema::LinerNotes has an accessor named notes, you can do 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 } ); $track->title('New Title'); @@ -297,9 +343,9 @@ For a 'belongs_to relationship, note the 'cascade_update': =item \%column A hashref where each key is the accessor you want installed in the main class, -and its value is the name of the original in the fireign class. +and its value is the name of the original in the foreign class. - MyApp::Schema::Track->belongs_to( cd => 'DBICTest::Schema::CD', 'cd', { + MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', { proxy => { cd_title => 'title' }, }); @@ -309,7 +355,7 @@ This will create an accessor named C on the C<$track> result object. 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' } ], }); @@ -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(@_) : {}); @@ -475,26 +523,18 @@ 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 $rel_info->{cond} eq 'CODE'; + if ($is_crosstable and ref $rel_info->{cond} eq 'CODE') { # A WHOREIFFIC hack to reinvoke the entire condition resolution # with the correct alias. Another way of doing this involves a @@ -519,7 +559,7 @@ sub related_resultset { # FIXME - this conditional doesn't seem correct - got to figure out # at some point what it does. Also the entire UNRESOLVABLE_CONDITION # business seems shady - we could simply not query *at all* - if ($cond eq $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION) { + if ($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') { @@ -627,36 +667,15 @@ 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 (undef, $crosstable, $cond_targets) = $rsrc->_resolve_condition ( - $rsrc->relationship_info($rel)->{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 => $rel, + self_alias => 'me', + )->{inferred_values} ); } =head2 create_related @@ -798,36 +817,13 @@ set them in the storage. sub set_from_related { my ($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; }