package DBIx::Class::ResultSet::RecursiveUpdate;
-our $VERSION = '0.013';
+# ABSTRACT: like update_or_create - but recursive
use base qw(DBIx::Class::ResultSet);
sub recursive_update {
- my ( $self, $updates, $fixed_fields ) = @_;
+ my ( $self, $updates, $attrs ) = @_;
+
+ my $fixed_fields;
+ my $unknown_params_ok;
+
+ # 0.21+ api
+ if ( defined $attrs && ref $attrs eq 'HASH' ) {
+ $fixed_fields = $attrs->{fixed_fields};
+ $unknown_params_ok = $attrs->{unknown_params_ok};
+ }
+
+ # pre 0.21 api
+ elsif ( defined $attrs && ref $attrs eq 'ARRAY' ) {
+ $fixed_fields = $attrs;
+ }
+
return
DBIx::Class::ResultSet::RecursiveUpdate::Functions::recursive_update(
- resultset => $self,
- updates => $updates,
- fixed_fields => $fixed_fields
+ resultset => $self,
+ updates => $updates,
+ fixed_fields => $fixed_fields,
+ unknown_params_ok => $unknown_params_ok,
);
}
package DBIx::Class::ResultSet::RecursiveUpdate::Functions;
-use Carp;
+use Carp::Clan qw/^DBIx::Class|^HTML::FormHandler|^Try::Tiny/;
use Scalar::Util qw( blessed );
+use List::MoreUtils qw/ any /;
sub recursive_update {
my %params = @_;
my ( $self, $updates, $fixed_fields, $object, $resolved,
- $if_not_submitted )
+ $if_not_submitted, $unknown_params_ok )
= @params{
- qw/resultset updates fixed_fields object resolved if_not_submitted/};
+ qw/resultset updates fixed_fields object resolved if_not_submitted unknown_params_ok/
+ };
$resolved ||= {};
- # warn 'entering: ' . $self->result_source->from();
- carp 'fixed fields needs to be an array ref'
- if $fixed_fields && ref($fixed_fields) ne 'ARRAY';
- my %fixed_fields;
- %fixed_fields = map { $_ => 1 } @$fixed_fields if $fixed_fields;
+ my $source = $self->result_source;
+
+ croak "first parameter needs to be defined"
+ unless defined $updates;
+
+ croak "first parameter needs to be a hashref"
+ unless ref($updates) eq 'HASH';
+
+ # warn 'entering: ' . $source->from();
+ croak 'fixed fields needs to be an arrayref'
+ if defined $fixed_fields && ref $fixed_fields ne 'ARRAY';
+
+ # always warn about additional parameters if storage debugging is enabled
+ $unknown_params_ok = 0
+ if $source->storage->debug;
+
if ( blessed($updates) && $updates->isa('DBIx::Class::Row') ) {
return $updates;
}
- if ( $updates->{id} ) {
+ if ( exists $updates->{id} ) {
+
+ # warn "finding object by id " . $updates->{id} . "\n";
$object = $self->find( $updates->{id}, { key => 'primary' } );
+
+ # warn "object not found by id\n"
+ # unless defined $object;
}
+
+ my %fixed_fields = map { $_ => 1 } @$fixed_fields
+ if $fixed_fields;
my @missing =
grep { !exists $updates->{$_} && !exists $fixed_fields{$_} }
- $self->result_source->primary_columns;
+ $source->primary_columns;
if ( !$object && !scalar @missing ) {
# warn 'finding by: ' . Dumper( $updates ); use Data::Dumper;
grep { !exists $resolved->{$_} } @missing;
if ( !$object && !scalar @missing ) {
- # warn 'finding by +resolved: ' . Dumper( $updates ); use Data::Dumper;
+ # warn 'finding by +resolved: ' . Dumper( $updates ); use Data::Dumper;
$object = $self->find( $updates, { key => 'primary' } );
}
- $object ||= $self->new( {} );
+
+ $object = $self->new( {} )
+ unless defined $object;
# warn Dumper( $updates ); use Data::Dumper;
# direct column accessors
# database like has_many, might_have and has_one
my %post_updates;
my %other_methods;
+ my %m2m_accessors;
my %columns_by_accessor = _get_columns_by_accessor($self);
# warn 'resolved: ' . Dumper( $resolved );
# warn 'updates: ' . Dumper( $updates ); use Data::Dumper;
# warn 'columns: ' . Dumper( \%columns_by_accessor );
for my $name ( keys %$updates ) {
- my $source = $self->result_source;
# columns
if ( exists $columns_by_accessor{$name}
&& ref( $updates->{$name} ) ) )
{
- #warn "$name is a column";
+ #warn "$name is a column\n";
$columns{$name} = $updates->{$name};
next;
}
# relationships
if ( $source->has_relationship($name) ) {
- my $info = $source->relationship_info($name);
- if (_master_relation_cond(
- $source, $info->{cond},
- _get_pk_for_related( $self, $name )
- )
- )
- {
+ if ( _master_relation_cond( $self, $name ) ) {
- #warn "$name is a pre-update rel";
+ #warn "$name is a pre-update rel\n";
$pre_updates{$name} = $updates->{$name};
next;
}
else {
- #warn "$name is a post-update rel";
+ #warn "$name is a post-update rel\n";
$post_updates{$name} = $updates->{$name};
next;
}
# many-to-many helper accessors
if ( is_m2m( $self, $name ) ) {
- #warn "$name is a many-to-many helper accessor";
- $other_methods{$name} = $updates->{$name};
+ #warn "$name is a many-to-many helper accessor\n";
+ $m2m_accessors{$name} = $updates->{$name};
next;
}
}
# unknown
- $self->throw_exception(
+
+ # don't throw a warning instead of an exception to give users
+ # time to adapt to the new API
+ carp(
"No such column, relationship, many-to-many helper accessor or generic accessor '$name'"
- );
+ ) unless $unknown_params_ok;
+
+#$self->throw_exception(
+# "No such column, relationship, many-to-many helper accessor or generic accessor '$name'"
+#);
}
# warn 'other: ' . Dumper( \%other_methods ); use Data::Dumper;
# first update columns and other accessors
# so that later related records can be found
for my $name ( keys %columns ) {
+
+ #warn "update col $name\n";
$object->$name( $columns{$name} );
}
for my $name ( keys %other_methods ) {
- $object->$name( $updates->{$name} );
+
+ #warn "update other $name\n";
+ $object->$name( $other_methods{$name} );
}
for my $name ( keys %pre_updates ) {
- _update_relation( $self, $name, $updates->{$name}, $object,
+
+ #warn "pre_update $name\n";
+ _update_relation( $self, $name, $pre_updates{$name}, $object,
$if_not_submitted );
}
# don't allow insert to recurse to related objects
# do the recursion ourselves
# $object->{_rel_in_storage} = 1;
+ #warn "CHANGED: " . $object->is_changed . "\n";
+ #warn "IN STOR: " . $object->in_storage . "\n";
$object->update_or_insert if $object->is_changed;
+ $object->discard_changes;
# updating many_to_many
- for my $name ( keys %$updates ) {
- next if exists $columns{$name};
- my $value = $updates->{$name};
-
- if ( is_m2m( $self, $name ) ) {
- my ($pk) = _get_pk_for_related( $self, $name );
- my @rows;
- my $result_source = $object->$name->result_source;
- my @updates;
- if ( !defined $value ) {
- next;
+ for my $name ( keys %m2m_accessors ) {
+ my $value = $m2m_accessors{$name};
+
+ #warn "update m2m $name\n";
+ # TODO: only first pk col is used
+ my ($pk) = _get_pk_for_related( $self, $name );
+ my @rows = ();
+ my $result_source = $object->$name->result_source;
+ my @updates;
+ if ( defined $value && ref $value eq 'ARRAY' ) {
+ @updates = @{$value};
+ }
+ elsif ( defined $value && !ref $value ) {
+ @updates = ($value);
+ }
+ else {
+ carp "value of many-to-many rel '$name' must be an arrayref or scalar";
+ }
+ for my $elem (@updates) {
+ if ( blessed($elem) && $elem->isa('DBIx::Class::Row') ) {
+ push @rows, $elem;
}
- elsif ( ref $value ) {
- @updates = @{$value};
+ elsif ( ref $elem eq 'HASH' ) {
+ push @rows,
+ recursive_update(
+ resultset => $result_source->resultset,
+ updates => $elem
+ );
}
else {
- @updates = ($value);
- }
- for my $elem (@updates) {
- if ( ref $elem ) {
- push @rows,
- recursive_update(
- resultset => $result_source->resultset,
- updates => $elem
- );
- }
- else {
- push @rows,
- $result_source->resultset->find( { $pk => $elem } );
- }
+ push @rows,
+ $result_source->resultset->find( { $pk => $elem } );
}
- my $set_meth = 'set_' . $name;
- $object->$set_meth( \@rows );
}
+ my $set_meth = 'set_' . $name;
+ $object->$set_meth( \@rows );
}
for my $name ( keys %post_updates ) {
- _update_relation( $self, $name, $updates->{$name}, $object,
+
+ #warn "post_update $name\n";
+ _update_relation( $self, $name, $post_updates{$name}, $object,
$if_not_submitted );
}
return $object;
return %columns;
}
-# Arguments: $name, $updates, $object, $if_not_submitted
-
+# Arguments: $rs, $name, $updates, $row, $if_not_submitted
sub _update_relation {
my ( $self, $name, $updates, $object, $if_not_submitted ) = @_;
# this should never happen because we're checking the paramters passed to
# recursive_update, but just to be sure...
- $object->throw_exception("No such relationship '$name' on ")
+ $object->throw_exception("No such relationship '$name'")
unless $object->has_relationship($name);
+ #warn "_update_relation $name: OBJ: " . ref($object) . "\n";
+
my $info = $object->result_source->relationship_info($name);
# get a related resultset without a condition
$self->result_source->_resolve_condition( $info->{cond}, $name,
$object );
}
+ else {
+ $self->throw_exception(
+ "result_source must support _resolve_condition");
+ }
# warn "$name resolved: " . Dumper( $resolved ); use Data::Dumper;
$resolved = {}
&& $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION
== $resolved;
- my $rel_col_cnt = scalar keys %{ $info->{cond} };
- use Data::Dumper;
- warn "RELINFO for $name: " . Dumper($info);
- warn "REL_COL_CNT: $rel_col_cnt";
+ my @rel_cols = keys %{ $info->{cond} };
+ map {s/^foreign\.//} @rel_cols;
+
+ #warn "REL_COLS: " . Dumper(@rel_cols); use Data::Dumper;
+ #my $rel_col_cnt = scalar @rel_cols;
+
+ # find out if all related columns are nullable
+ my $all_fks_nullable = 1;
+ for my $rel_col (@rel_cols) {
+ $all_fks_nullable = 0
+ unless $related_resultset->result_source->column_info($rel_col)
+ ->{is_nullable};
+ }
+
+ $if_not_submitted = $all_fks_nullable ? 'nullify' : 'delete'
+ unless defined $if_not_submitted;
+
+ #warn "\tNULLABLE: $all_fks_nullable ACTION: $if_not_submitted\n";
- #warn "REV RELINFO for $name: " . Dumper($revrelinfo);
+ #warn "RELINFO for $name: " . Dumper($info); use Data::Dumper;
# the only valid datatype for a has_many rels is an arrayref
- if ( $info->{attrs}{accessor} eq 'multi') {
- $self->throw_exception( "data for has_many relationship '$name' must be an arrayref")
+ if ( $info->{attrs}{accessor} eq 'multi' ) {
+
+ # handle undef like empty arrayref
+ $updates = []
+ unless defined $updates;
+ $self->throw_exception(
+ "data for has_many relationship '$name' must be an arrayref")
unless ref $updates eq 'ARRAY';
- my @updated_ids;
+ my @updated_objs;
+
+ #warn "\tupdating has_many rel '$name' ($rel_col_cnt columns cols)\n";
for my $sub_updates ( @{$updates} ) {
- warn "updating $name";
my $sub_object = recursive_update(
resultset => $related_resultset,
updates => $sub_updates,
resolved => $resolved
);
- push @updated_ids, $sub_object->id;
+
+ push @updated_objs, $sub_object;
}
+
+ #warn "\tcreated and updated related rows\n";
+
my @related_pks = $related_resultset->result_source->primary_columns;
- if ( defined $if_not_submitted && $if_not_submitted eq 'delete' ) {
- # only handles related result classes with single primary keys
- if ( 1 == scalar @related_pks ) {
- $object->$name->search(
- { $related_pks[0] => { -not_in => \@updated_ids } } )
- ->delete;
- }
+ my $rs_rel_delist = $object->$name;
+
+ # foreign table has a single pk column
+ if ( scalar @related_pks == 1 ) {
+ $rs_rel_delist = $rs_rel_delist->search_rs(
+ { $related_pks[0] =>
+ { -not_in => [ map ( $_->id, @updated_objs ) ] }
+ }
+ );
}
- elsif ( defined $if_not_submitted
- && $if_not_submitted eq 'set_to_null' )
- {
- # only handles related result classes with single primary keys
- if ( 1 == scalar @related_pks ) {
- my @fk = keys %$resolved;
- $object->$name->search(
- { $related_pks[0] => { -not_in => \@updated_ids } } )
- ->update( { $fk[0] => undef } );
+ # foreign table has multiple pk columns
+ else {
+ my @cond;
+ for my $obj (@updated_objs) {
+ my %cond_for_obj;
+ for my $col (@related_pks) {
+ $cond_for_obj{$col} = $obj->get_column($col);
+ }
+ push @cond, \%cond_for_obj;
+ }
+
+ # only limit resultset if there are related rows left
+ if ( scalar @cond ) {
+ $rs_rel_delist =
+ $rs_rel_delist->search_rs( { -not => [@cond] } );
}
}
+
+ #warn "\tCOND: " . Dumper(\%cond);
+ #my $rel_delist_cnt = $rs_rel_delist->count;
+ if ( $if_not_submitted eq 'delete' ) {
+
+ #warn "\tdeleting related rows: $rel_delist_cnt\n";
+ $rs_rel_delist->delete;
+ }
+ elsif ( $if_not_submitted eq 'set_to_null' ) {
+
+ #warn "\tnullifying related rows: $rel_delist_cnt\n";
+ my %update = map { $_ => undef } @rel_cols;
+ $rs_rel_delist->update( \%update );
+ }
}
elsif ($info->{attrs}{accessor} eq 'single'
|| $info->{attrs}{accessor} eq 'filter' )
{
+
+ #warn "\tupdating rel '$name': $if_not_submitted\n";
my $sub_object;
if ( ref $updates ) {
+ if ( blessed($updates) && $updates->isa('DBIx::Class::Row') ) {
+ $sub_object = $updates;
+ }
# for might_have relationship
- if ( $info->{attrs}{accessor} eq 'single'
+ elsif ( $info->{attrs}{accessor} eq 'single'
&& defined $object->$name )
{
$sub_object = recursive_update(
);
}
else {
- $self->throw_exception( "recursive_update doesn't now how to handle relationship '$name' with accessor " . $info->{attrs}{accessor});
+ $self->throw_exception(
+ "recursive_update doesn't now how to handle relationship '$name' with accessor "
+ . $info->{attrs}{accessor} );
}
}
# after the row is inserted into the database
# relationships before: belongs_to
# relationships after: has_many, might_have and has_one
+# true means before, false after
sub _master_relation_cond {
- my ( $source, $cond, @foreign_ids ) = @_;
- my $foreign_ids_re = join '|', @foreign_ids;
- if ( ref $cond eq 'HASH' ) {
- for my $f_key ( keys %{$cond} ) {
+ my ( $self, $name ) = @_;
+
+ my $source = $self->result_source;
+ my $info = $source->relationship_info($name);
+
+ #warn "INFO: " . Dumper($info) . "\n";
+
+ # has_many rels are always after
+ return 0
+ if $info->{attrs}->{accessor} eq 'multi';
+
+ my @foreign_ids = _get_pk_for_related( $self, $name );
+
+ #warn "IDS: " . join(', ', @foreign_ids) . "\n";
+
+ my $cond = $info->{cond};
+
+ sub _inner {
+ my ( $source, $cond, @foreign_ids ) = @_;
+
+ while ( my ( $f_key, $col ) = each %{$cond} ) {
# might_have is not master
- my $col = $cond->{$f_key};
- $col =~ s/self\.//;
+ $col =~ s/^self\.//;
+ $f_key =~ s/^foreign\.//;
if ( $source->column_info($col)->{is_auto_increment} ) {
return 0;
}
- if ( $f_key =~ /^foreign\.$foreign_ids_re/ ) {
+ if ( any { $_ eq $f_key } @foreign_ids ) {
return 1;
}
}
+ return 0;
}
+
+ if ( ref $cond eq 'HASH' ) {
+ return _inner( $source, $cond, @foreign_ids );
+ }
+
+ # arrayref of hashrefs
elsif ( ref $cond eq 'ARRAY' ) {
for my $new_cond (@$cond) {
- return _master_relation_cond( $source, $new_cond, @foreign_ids );
+ return _inner( $source, $new_cond, @foreign_ids );
}
}
+ else {
+ $source->throw_exception(
+ "unhandled relation condition " . ref($cond) );
+ }
return;
}
1; # Magic true value required at end of module
__END__
-=head1 NAME
-
-DBIx::Class::ResultSet::RecursiveUpdate - like update_or_create - but recursive
-
=head1 SYNOPSIS
-The functional interface:
+ # The functional interface:
- my $new_item = DBIx::Class::ResultSet::RecursiveUpdate::Functions::recursive_update({
- resultset => $schema->resultset( 'Dvd' ),
+ my $schema = MyDB::Schema->connect();
+ my $new_item = DBIx::Class::ResultSet::RecursiveUpdate::Functions::recursive_update(
+ resultset => $schema->resultset('User'),
updates => {
- id => 1,
- owned_dvds => [
- {
- title => 'One Flew Over the Cuckoo's Nest'
- }
- ]
- }
- });
+ id => 1,
+ owned_dvds => [
+ {
+ title => "One Flew Over the Cuckoo's Nest"
+ }
+ ]
+ },
+ unknown_params_ok => 1,
+ );
-As ResultSet subclass:
+ # As ResultSet subclass:
__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.
+ # in the Schema file (see t/lib/DBSchema.pm). Or appropriate 'use base' in the ResultSet classes.
-Then:
+ my $user = $schema->resultset('User')->recursive_update({
+ id => 1,
+ owned_dvds => [
+ {
+ title => "One Flew Over the Cuckoo's Nest"
+ }
+ ]
+ }, {
+ unknown_params_ok => 1,
+ });
- my $user = $user_rs->recursive_update( {
- id => 1,
- owned_dvds => [
- {
- title => 'One Flew Over the Cuckoo's Nest'
- }
- ]
- }
- );
+ # You'll get a warning if you pass non-result specific data to
+ # recursive_update. See L</"Additional data in the updates hashref">
+ # for more information how to prevent this.
-
=head1 DESCRIPTION
-This is still experimental. I've added a functional interface so that it can be used
-in Form Processors and not require modification of the model.
+This is still experimental.
-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.
+You can feed the ->create method of DBIx::Class 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 until
+L<DBIx::Class> has an api itself.
-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).
-If not all colums comprising the primary key are specified - then a new row will be created,
-with the expectation that the missing columns will be filled by it (as in the case of auto_increment
-primary keys).
+The functional interface can be used without modifications of the model,
+for example by form processors like L<HTML::FormHandler::Model::DBIC>.
+It is a base class for L<DBIx::Class::ResultSet>s providing the method
+recursive_update which works just like update_or_create but can recursively
+update or create result 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 a related row of
+a belongs_to relationship). If any of the primary key columns are missing,
+a new row will be created, with the expectation that the missing columns will
+be filled by it (as in the case of auto_increment primary keys).
-If the resultset itself stores an assignement for the primary key,
+If the resultset itself stores an assignment for the primary key,
like in the case of:
my $restricted_rs = $user_rs->search( { id => 1 } );
-then you need to inform recursive_update about additional predicate with a second argument:
+you need to inform recursive_update about the additional predicate with the fixed_fields attribute:
- my $user = $restricted_rs->recursive_update( {
- owned_dvds => [
- {
- title => 'One Flew Over the Cuckoo's Nest'
- }
- ]
- },
- [ 'id' ]
+ my $user = $restricted_rs->recursive_update( {
+ owned_dvds => [
+ {
+ title => 'One Flew Over the Cuckoo's Nest'
+ }
+ ]
+ },
+ {
+ fixed_fields => [ 'id' ],
+ }
);
-This will work with a new DBIC release.
-
For a many_to_many (pseudo) relation you can supply a list of primary keys
-from the other table - and it will link the record at hand to those and
-only those records identified by them. This is convenient for handling web
-forms with check boxes (or a SELECT box with multiple choice) that let you
+from the other table and it will link the record at hand to those and
+only those records identified by them. This is convenient for handling web
+forms with check boxes (or a select field with multiple choice) that lets you
update such (pseudo) relations.
-For a description how to set up base classes for ResultSets see load_namespaces
-in DBIx::Class::Schema.
+For a description how to set up base classes for ResultSets see
+L<DBIx::Class::Schema/load_namespaces>.
+
+=head2 Additional data in the updates hashref
+
+If you pass additional data to recursive_update which doesn't match a column
+name, column accessor, relationship or many-to-many helper accessor, it will
+throw a warning by default. To disable this behaviour you can set the
+unknown_params_ok attribute to a true value.
+
+The warning thrown is:
+"No such column, relationship, many-to-many helper accessor or generic accessor '$key'"
+
+When used by L<HTML::FormHandler::Model::DBIC> this can happen if you have
+additional form fields that aren't relevant to the database but don't have the
+noupdate attribute set to a true value.
+
+NOTE: in a future version this behaviour will change and throw an exception
+instead of a warning!
+
=head1 DESIGN CHOICES
In this case recursive_update deletes the foreign rows.
+Updating the relationship:
+
+ Passing ids:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => [1, 2],
+ });
+
+ Passing hashrefs:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => [
+ {
+ name => 'temp name 1',
+ },
+ {
+ name => 'temp name 2',
+ },
+ ],
+ });
+
+ Passing objects:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => [ $dvd1, $dvd2 ],
+ });
+
+ You can even mix them:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => [ 1, { id => 2 } ],
+ });
+
+Clearing the relationship:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => undef,
+ });
+
+ This is the same as passing an empty array:
+
+ my $user = $user_rs->recursive_update( {
+ id => 1,
+ owned_dvds => [],
+ });
+
+=head2 Treatment of many-to-many pseudo relations
+
+If a many-to-many accessor key is included in the data structure with a value
+of undef or an empty array, all existing related rows are unlinked.
+
+When the array contains elements they are updated if they exist, created when
+not and deleted if not included.
+
+See L</is_m2m> for many-to-many pseudo relationship detection.
+
Updating the relationship:
Passing ids:
Passing objects:
- TODO
+ my $dvd = $dvd_rs->recursive_update( {
+ id => 1,
+ tags => [ $tag1, $tag2 ],
+ });
You can even mix them:
my $dvd = $dvd_rs->recursive_update( {
id => 1,
- tags => [ '2', { id => '3' } ],
+ tags => [ 2, { id => 3 } ],
});
Clearing the relationship:
tags => [],
});
-=head2 Treatment of many-to-many pseudo relations
-
-The function gets the information about m2m relations from DBIx::Class::IntrospectableM2M.
-If it isn't loaded in the ResultSource classes the code relies on the fact that:
-
- if($object->can($name) and
- !$object->result_source->has_relationship($name) and
- $object->can( 'set_' . $name )
- )
-
-Then $name must be a many to many pseudo relation.
-And that in a similarly ugly was I find out what is the ResultSource of
-objects from that many to many pseudo relation.
-
=head1 INTERFACE
=head2 is_m2m
-$self->is_m2m( 'name ' ) - answers the question if 'name' is a many to many
-(pseudo) relation on $self.
+=over 4
+
+=item Arguments: $name
+
+=item Return Value: true, if $name is a many to many pseudo-relationship
+
+=back
+
+The function gets the information about m2m relations from
+L<DBIx::Class::IntrospectableM2M>. If it isn't loaded in the ResultSource
+class, the code relies on the fact:
+
+ if($object->can($name) and
+ !$object->result_source->has_relationship($name) and
+ $object->can( 'set_' . $name )
+ )
+
+to identify a many to many pseudo relationship. In a similar ugly way the
+ResultSource of that many to many pseudo relationship is detected.
+
+So if you need many to many pseudo relationship support, it's strongly
+recommended to load L<DBIx::Class::IntrospectableM2M> in your ResultSource
+class!
=head2 get_m2m_source
-$self->get_m2m_source( 'name' ) - returns the ResultSource linked to by the many
-to many (pseudo) relation 'name' from $self.
+=over 4
+=item Arguments: $name
-=head1 DIAGNOSTICS
+=item Return Value: $result_source
+=back
=head1 CONFIGURATION AND ENVIRONMENT
DBIx::Class
+optional but recommended:
+ DBIx::Class::IntrospectableM2M
+
=head1 INCOMPATIBILITIES
None reported.
=head1 BUGS AND LIMITATIONS
-No bugs have been reported.
+The list of reported bugs can be viewed at L<http://rt.cpan.org/Public/Dist/Display.html?Name=DBIx-Class-ResultSet-RecursiveUpdate>.
Please report any bugs or feature requests to
C<bug-dbix-class-recursiveput@rt.cpan.org>, or through the web interface at
L<http://rt.cpan.org>.
-
-
-=head1 AUTHOR
-
-Zbigniew Lukasiak C<< <zby@cpan.org> >>
-Influenced by code by Pedro Melo.
-
-=head1 LICENCE AND COPYRIGHT
-
-Copyright (c) 2008, Zbigniew Lukasiak C<< <zby@cpan.org> >>. All rights reserved.
-
-This module is free software; you can redistribute it and/or
-modify it under the same terms as Perl itself. See L<perlartistic>.
-
-
-=head1 DISCLAIMER OF WARRANTY
-
-BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
-FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
-OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
-PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
-EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
-ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
-YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
-NECESSARY SERVICING, REPAIR, OR CORRECTION.
-
-IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
-REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
-LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
-OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
-THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
-RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
-FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
-SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGES.