package DBIx::Class::ResultSet::RecursiveUpdate;
-use version; $VERSION = qv('0.0.1');
+use version; $VERSION = qv('0.001');
use warnings;
use strict;
sub recursive_update {
my( $self, $updates ) = @_;
my $object;
- # this is a workaround for a bug in the svn version 4794
- if ( ref $self->{cond} eq 'ARRAY' and ref $self->{cond}[0] eq 'SCALAR' ){
- $self->{cond} = {};
- $object = $self->new( {} );
- }
- else {
- $object = $self->find( $updates, { key => 'primary' } ) || $self->new( {} );
- }
+ $object = $self->find( $updates, { key => 'primary' } ) || $self->new( {} );
- for my $name ( keys %$updates ){ if($object->can($name)){
+ for my $name ( keys %$updates ){
+ if($object->can($name)){
my $value = $updates->{$name};
+
# updating relations that that should be done before the row is inserted into the database
# like belongs_to
if( $object->result_source->has_relationship($name)
my $info = $object->result_source->relationship_info( $name );
if( $info and not $info->{attrs}{accessor} eq 'multi'
and
- _master_relation_cond( $object, $info->{cond}, _get_pk_for_related( $object, $name ) )
+ _master_relation_cond( $object, $info->{cond}, $self->_get_pk_for_related( $name ) )
){
my $related_result = $object->related_resultset( $name );
- $DB::single = 1;
my $sub_object = $related_result->recursive_update( $value );
$object->set_from_related( $name, $sub_object );
}
}
#warn Dumper($object->{_column_data}); use Data::Dumper;
}
- _delete_empty_auto_increment($object);
+ $self->_delete_empty_auto_increment($object);
+ # don't allow insert to recurse to related objects - we do the recursion ourselves
+ $object->{_rel_in_storage} = 1;
$object->update_or_insert;
# updating relations that can be done only after the row is inserted into the database
for my $name ( keys %$updates ){
my $value = $updates->{$name};
# many to many case
- if($object->can($name) and
- !$object->result_source->has_relationship($name) and
- $object->can( 'set_' . $name )
- ) {
- my ( $pk ) = _get_pk_for_related( $object, $name );
+ if( $self->is_m2m( $name ) ) {
+ my ( $pk ) = $self->_get_pk_for_related( $name );
my @values = @{$updates->{$name}};
my @rows;
my $result_source = $object->$name->result_source;
}
}
# might_have and has_one case
- elsif ( ! _master_relation_cond( $object, $info->{cond}, _get_pk_for_related( $object, $name ) ) ){
+ elsif ( ! _master_relation_cond( $object, $info->{cond}, $self->_get_pk_for_related( $name ) ) ){
my $sub_object = $object->search_related( $name )->recursive_update( $value );
#$object->set_from_related( $name, $sub_object );
}
return $object;
}
+sub is_m2m {
+ my( $self, $relation ) = @_;
+ my $object = $self->new({});
+ if ( $object->can($relation) and
+ !$object->result_source->has_relationship($relation) and
+ $object->can( 'set_' . $relation)
+ ){
+ return 1;
+ }
+ return;
+}
+
+sub get_m2m_source {
+ my( $self, $relation ) = @_;
+ my $object = $self->new({});
+ my $r = $object->$relation;
+ return $r->result_source;
+}
+
+
sub _delete_empty_auto_increment {
- my ( $object ) = @_;
+ my ( $self, $object ) = @_;
for my $col ( keys %{$object->{_column_data}}){
if( $object->result_source->column_info( $col )->{is_auto_increment}
and
}
sub _get_pk_for_related {
- my ( $object, $relation ) = @_;
+ my ( $self, $relation ) = @_;
- my $rs = $object->result_source->resultset;
- my $result_source = _get_related_source( $rs, $relation );
- return $result_source->primary_columns;
-}
-
-sub _get_related_source {
- my ( $rs, $name ) = @_;
- if( $rs->result_source->has_relationship( $name ) ){
- return $rs->result_source->related_source( $name );
+ my $result_source;
+ if( $self->result_source->has_relationship( $relation ) ){
+ $result_source = $self->result_source->related_source( $relation );
}
# many to many case
- my $row = $rs->new({});
- if ( $row->can( $name ) and $row->can( 'add_to_' . $name ) and $row->can( 'set_' . $name ) ){
- my $r = $row->$name;
- return $r->result_source;
+ if ( $self->is_m2m( $relation ) ) {
+ $result_source = $self->get_m2m_source( $relation );
}
- return;
+ return $result_source->primary_columns;
}
sub _master_relation_cond {
=head1 VERSION
-This document describes DBIx::Class::ResultSet::RecursiveUpdate version 0.0.1
+This document describes DBIx::Class::ResultSet::RecursiveUpdate version 0.001
=head1 SYNOPSIS
- __PACKAGE__->load_namespaces( default_resultset_class => '+DBIx::Class::ResultSet::RecursiveUpdate' );
+ __PACKAGE__->load_namespaces( default_resultset_class => '+DBIx::Class::ResultSet::RecursiveUpdate' );
in the Schema file (see t/lib/DBSchema.pm). Or appriopriate 'use base' in the ResultSet classes.
Then:
-=for author to fill in:
-
my $user = $user_rs->recursive_update( {
id => 1,
owned_dvds => [
=head1 DESCRIPTION
-=for author to fill in:
- You can feed the ->create method with a recursive datastructure and have the related records
- created. Unfortunately you cannot do a similar thing with update_or_create - this module
- tries to fill that void.
- It is a base class for ResultSets providing just one method: recursive_update
- which works just like update_or_create but can recursively update or create
- data objects composed of multiple rows. All rows need to be identified by primary keys
- - so you need to provide them in the update structure (unless they can be deduced from
- the parent row - for example when you have a belongs_to relationship).
- When creating new rows in a table with auto_increment primary keys you need to
- put 'undef' for the key value - this is then removed
- and a correct INSERT statement is generated.
-
- For a description how to set up base classes for ResultSets see load_namespaces
- in DBIx::Class::Schema.
+You can feed the ->create method with a recursive datastructure and have the related records
+created. Unfortunately you cannot do a similar thing with update_or_create - this module
+tries to fill that void.
-=head1 INTERFACE
+It is a base class for ResultSets providing just one method: recursive_update
+which works just like update_or_create but can recursively update or create
+data objects composed of multiple rows. All rows need to be identified by primary keys
+- so you need to provide them in the update structure (unless they can be deduced from
+the parent row - for example when you have a belongs_to relationship).
+When creating new rows in a table with auto_increment primary keys you need to
+put 'undef' for the key value - this is then removed
+and a correct INSERT statement is generated.
-=for author to fill in:
+For a many_to_many (pseudo) relation you can supply a list of primary keys
+from the other table - and it will link the record at hand to those and
+only those records identified by them. This is convenient for handling web
+forms with check boxes (or a SELECT box with multiple choice) that let you
+update such (pseudo) relations.
+
+For a description how to set up base classes for ResultSets see load_namespaces
+in DBIx::Class::Schema.
+
+=head1 DESIGN CHOICES
+
+=head2 Treatment of many to many pseudo relations
+
+Matt Trout expressed following criticism of the support for many to many in
+RecursiveUpdate and since this is an extension of his DBIx::Class I feel obliged to
+reply to it. It is about two points leading in his opinion to 'fragile and
+implicitely broken code'.
+
+1. That I rely on the fact that
+
+ if($object->can($name) and
+ !$object->result_source->has_relationship($name) and
+ $object->can( 'set_' . $name )
+ )
+
+then $name must be a many to many pseudo relation. And that in a
+similarly ugly was I find out what is the ResultSource of objects from
+that many to many pseudo relation.
+
+2. That I treat uniformly relations and many to many (which are
+different from relations because they require traversal of the bridge
+table).
+
+To answer 1) I've refactored that 'dirty' code into is_m2m and get_m2m_source so
+that it can be easily overridden. I agree that this code is not too nice - but
+currenlty it is the only way to do what I need - and I'll replace it as soon as
+there is a more clean way. I don't think it is extremely brittle - sure it will
+break if many to many (pseudo) relations don't get 'set_*' methods anymore - but
+I would say it is rather justified for this kind of change in underlying library
+to break it.
+
+
+Ad 2) - first this is not strictly true - RecursiveUpdate does have
+different code to cope with m2m and other cases (see the point above for
+example) - but it let's the user to treat m2m and 'normal' relations in a
+uniform way. I consider this a form of abstraction - it is the work that
+RecursiveUpdate does for the programmer.
+
+
+=head1 INTERFACE
=head1 METHODS
=head2 recursive_update
-The only method here.
+The method that does the work here.
+
+=head2 is_m2m
+
+$self->is_m2m( 'name ' ) - answers the question if 'name' is a many to many
+(pseudo) relation on $self.
+
+=head2 get_m2m_source
+
+$self->get_m2m_source( 'name' ) - returns the ResultSource linked to by the many
+to many (pseudo) relation 'name' from $self.
+
=head1 DIAGNOSTICS
=head1 CONFIGURATION AND ENVIRONMENT
-=for author to fill in:
-
DBIx::Class::RecursiveUpdate requires no configuration files or environment variables.
-
=head1 DEPENDENCIES
-=for author to fill in:
-
DBIx::Class
-None.
-
-
=head1 INCOMPATIBILITIES
=for author to fill in:
projects / chaz / p5-DBIx-Class-ResultSet-RecursiveUpdate / blobdiff