Dogcows Code - chaz/p5-DBIx-Class-ResultSet-RecursiveUpdate/blob - lib/DBIx/Class/ResultSet/RecursiveUpdate.pm

   1 package DBIx::Class::ResultSet::RecursiveUpdate;
   2
   3 use version; $VERSION = qv('0.001');
   4
   5 use warnings;
   6 use strict;
   7 use Carp;
   8 use Scalar::Util qw( blessed );
   9
  10 use base qw(DBIx::Class::ResultSet);
  11
  12 sub recursive_update {
  13     my ( $self, $updates, $fixed_fields ) = @_;
  14     # warn 'entering: ' . $self->result_source->from();
  15
  16     carp 'fixed fields needs to be an array ref' if $fixed_fields && ref($fixed_fields) ne 'ARRAY';
  17     my %fixed_fields;
  18     %fixed_fields = map { $_ => 1 } @$fixed_fields if $fixed_fields;
  19
  20     if ( blessed($updates) && $updates->isa('DBIx::Class::Row') ) {
  21         return $updates;
  22     }
  23
  24
  25     # direct column accessors
  26     my %columns;
  27
  28     # relations that that should be done before the row is inserted into the database
  29     # like belongs_to
  30     my %pre_updates;
  31
  32     # relations that that should be done after the row is inserted into the database
  33     # like has_many and might_have
  34     my %post_updates;
  35     my %columns_by_accessor = $self->_get_columns_by_accessor;
  36
  37     for my $name ( keys %$updates ) {
  38         my $source = $self->result_source;
  39         if ( $columns_by_accessor{$name}
  40             && !( $source->has_relationship($name) && ref( $updates->{$name} ) )
  41           )
  42         {
  43             $columns{$name} = $updates->{$name};
  44             next;
  45         }
  46         next if !$source->has_relationship($name);
  47         my $info = $source->relationship_info($name);
  48         if (
  49             _master_relation_cond(
  50                 $source, $info->{cond}, $self->_get_pk_for_related($name)
  51             )
  52           )
  53         {
  54             $pre_updates{$name} = $updates->{$name};
  55         }
  56         else {
  57             $post_updates{$name} = $updates->{$name};
  58         }
  59     }
  60     # warn 'columns: ' . Dumper( \%columns ); use Data::Dumper;
  61
  62     my $object;
  63     my @missing =
  64       grep { !exists $columns{$_} && !exists $fixed_fields{$_} } $self->result_source->primary_columns;
  65     if ( !scalar @missing ) {
  66         $object = $self->find( \%columns, { key => 'primary' } );
  67     }
  68     $object ||= $self->new( {} );
  69
  70 # first update columns and other accessors - so that later related records can be found
  71     for my $name ( keys %columns ) {
  72         $object->$name( $updates->{$name} );
  73     }
  74     for my $name ( keys %pre_updates ) {
  75         my $info = $object->result_source->relationship_info($name);
  76         $self->_update_relation( $name, $updates, $object, $info );
  77     }
  78 #    $self->_delete_empty_auto_increment($object);
  79
  80 # don't allow insert to recurse to related objects - we do the recursion ourselves
  81 #    $object->{_rel_in_storage} = 1;
  82     $object->update_or_insert;
  83
  84     # updating many_to_many
  85     for my $name ( keys %$updates ) {
  86         next if exists $columns{$name};
  87         my $value = $updates->{$name};
  88
  89         if ( $self->is_m2m($name) ) {
  90             my ($pk) = $self->_get_pk_for_related($name);
  91             my @rows;
  92             my $result_source = $object->$name->result_source;
  93             for my $elem ( @{ $updates->{$name} } ) {
  94                 if ( ref $elem ) {
  95                     push @rows, $result_source->resultset->find($elem);
  96                 }
  97                 else {
  98                     push @rows,
  99                       $result_source->resultset->find( { $pk => $elem } );
 100                 }
 101             }
 102             my $set_meth = 'set_' . $name;
 103             $object->$set_meth( \@rows );
 104         }
 105     }
 106     for my $name ( keys %post_updates ) {
 107         my $info = $object->result_source->relationship_info($name);
 108         $self->_update_relation( $name, $updates, $object, $info );
 109     }
 110     return $object;
 111 }
 112
 113 sub _get_columns_by_accessor {
 114     my $self   = shift;
 115     my $source = $self->result_source;
 116     my %columns;
 117     for my $name ( $source->columns ) {
 118         my $info = $source->column_info($name);
 119         $info->{name} = $name;
 120         $columns{ $info->{accessor} || $name } = $info;
 121     }
 122     return %columns;
 123 }
 124
 125 sub _update_relation {
 126     my ( $self, $name, $updates, $object, $info ) = @_;
 127
 128     my $related_result =
 129       $self->related_resultset($name)->result_source->resultset;
 130     my $resolved =
 131       $self->result_source->resolve_condition( $info->{cond}, $name, $object );
 132
 133  #                    warn 'resolved: ' . Dumper( $resolved ); use Data::Dumper;
 134     $resolved = undef
 135       if defined $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION && $DBIx::Class::ResultSource::UNRESOLVABLE_CONDITION == $resolved;
 136     if ( ref $updates->{$name} eq 'ARRAY' ) {
 137         for my $sub_updates ( @{ $updates->{$name} } ) {
 138             $sub_updates = { %$sub_updates, %$resolved } if $resolved && ref( $sub_updates ) eq 'HASH';
 139             my $sub_object =
 140               $related_result->recursive_update( $sub_updates );
 141         }
 142     }
 143     else {
 144         my $sub_updates = $updates->{$name};
 145         $sub_updates = { %$sub_updates, %$resolved } if $resolved && ref( $sub_updates ) eq 'HASH';
 146         my $sub_object =
 147           $related_result->recursive_update( $sub_updates );
 148         $object->set_from_related( $name, $sub_object );
 149     }
 150 }
 151
 152 sub is_m2m {
 153     my ( $self, $relation ) = @_;
 154     my $rclass = $self->result_class;
 155
 156     # DBIx::Class::IntrospectableM2M
 157     if ( $rclass->can('_m2m_metadata') ) {
 158         return $rclass->_m2m_metadata->{$relation};
 159     }
 160     my $object = $self->new( {} );
 161     if (    $object->can($relation)
 162         and !$self->result_source->has_relationship($relation)
 163         and $object->can( 'set_' . $relation ) )
 164     {
 165         return 1;
 166     }
 167     return;
 168 }
 169
 170 sub get_m2m_source {
 171     my ( $self, $relation ) = @_;
 172     my $rclass = $self->result_class;
 173
 174     # DBIx::Class::IntrospectableM2M
 175     if ( $rclass->can('_m2m_metadata') ) {
 176         return $self->result_source->related_source(
 177             $rclass->_m2m_metadata->{$relation}{relation} )
 178           ->related_source(
 179             $rclass->_m2m_metadata->{$relation}{foreign_relation} );
 180     }
 181     my $object = $self->new( {} );
 182     my $r = $object->$relation;
 183     return $r->result_source;
 184 }
 185
 186 sub _delete_empty_auto_increment {
 187     my ( $self, $object ) = @_;
 188     for my $col ( keys %{ $object->{_column_data} } ) {
 189         if (
 190             $object->result_source->column_info($col)->{is_auto_increment}
 191             and ( !defined $object->{_column_data}{$col}
 192                 or $object->{_column_data}{$col} eq '' )
 193           )
 194         {
 195             delete $object->{_column_data}{$col};
 196         }
 197     }
 198 }
 199
 200 sub _get_pk_for_related {
 201     my ( $self, $relation ) = @_;
 202     my $result_source;
 203     if ( $self->result_source->has_relationship($relation) ) {
 204         $result_source = $self->result_source->related_source($relation);
 205     }
 206
 207     # many to many case
 208     if ( $self->is_m2m($relation) ) {
 209         $result_source = $self->get_m2m_source($relation);
 210     }
 211     return $result_source->primary_columns;
 212 }
 213
 214 sub _master_relation_cond {
 215     my ( $source, $cond, @foreign_ids ) = @_;
 216     my $foreign_ids_re = join '|', @foreign_ids;
 217     if ( ref $cond eq 'HASH' ) {
 218         for my $f_key ( keys %{$cond} ) {
 219
 220             # might_have is not master
 221             my $col = $cond->{$f_key};
 222             $col =~ s/self\.//;
 223             if ( $source->column_info($col)->{is_auto_increment} ) {
 224                 return 0;
 225             }
 226             if ( $f_key =~ /^foreign\.$foreign_ids_re/ ) {
 227                 return 1;
 228             }
 229         }
 230     }
 231     elsif ( ref $cond eq 'ARRAY' ) {
 232         for my $new_cond (@$cond) {
 233             return 1
 234               if _master_relation_cond( $source, $new_cond, @foreign_ids );
 235         }
 236     }
 237     return;
 238 }
 239
 240 1;    # Magic true value required at end of module
 241 __END__
 242
 243 =head1 NAME
 244
 245 DBIx::Class::ResultSet::RecursiveUpdate - like update_or_create - but recursive
 246
 247
 248 =head1 VERSION
 249
 250 This document describes DBIx::Class::ResultSet::RecursiveUpdate version 0.001
 251
 252
 253 =head1 SYNOPSIS
 254
 255     __PACKAGE__->load_namespaces( default_resultset_class => '+DBIx::Class::ResultSet::RecursiveUpdate' );
 256
 257 in the Schema file (see t/lib/DBSchema.pm).  Or appriopriate 'use base' in the ResultSet classes.
 258
 259 Then:
 260
 261     my $user = $user_rs->recursive_update( {
 262         id => 1,
 263         owned_dvds => [
 264         {
 265           title => 'One Flew Over the Cuckoo's Nest'
 266         }
 267         ]
 268       }
 269     );
 270
 271
 272 =head1 DESCRIPTION
 273 This is the first release - so treat it as experimental.
 274
 275 You can feed the ->create method with a recursive datastructure and have the related records
 276 created.  Unfortunately you cannot do a similar thing with update_or_create - this module
 277 tries to fill that void.
 278
 279 It is a base class for ResultSets providing just one method: recursive_update
 280 which works just like update_or_create but can recursively update or create
 281 data objects composed of multiple rows. All rows need to be identified by primary keys
 282 - so you need to provide them in the update structure (unless they can be deduced from
 283 the parent row - for example when you have a belongs_to relationship).
 284 If not all colums comprising the primary key are specified - then a new row will be created,
 285 with the expectation that the missing columns will be filled by it (as in the case of auto_increment
 286 primary keys).
 287
 288
 289 If the resultset itself stores an assignement for the primary key,
 290 like in the case of:
 291
 292     my $restricted_rs = $user_rs->search( { id => 1 } );
 293
 294 then you need to inform recursive_update about additional predicate with a second argument:
 295
 296     my $user = $restricted_rs->recursive_update( {
 297         owned_dvds => [
 298         {
 299           title => 'One Flew Over the Cuckoo's Nest'
 300         }
 301         ]
 302       },
 303       [ 'id' ]
 304     );
 305
 306 This will work with a new DBIC release.
 307
 308 For a many_to_many (pseudo) relation you can supply a list of primary keys
 309 from the other table - and it will link the record at hand to those and
 310 only those records identified by them.  This is convenient for handling web
 311 forms with check boxes (or a SELECT box with multiple choice) that let you
 312 update such (pseudo) relations.
 313
 314 For a description how to set up base classes for ResultSets see load_namespaces
 315 in DBIx::Class::Schema.
 316
 317 =head1 DESIGN CHOICES
 318
 319 =head2 Treatment of many to many pseudo relations
 320
 321 The function gets the information about m2m relations from DBIx::Class::IntrospectableM2M.
 322 If it is not loaded in the ResultSource classes - then the code relies on the fact that:
 323     if($object->can($name) and
 324              !$object->result_source->has_relationship($name) and
 325              $object->can( 'set_' . $name )
 326          )
 327
 328 then $name must be a many to many pseudo relation.  And that in a
 329 similarly ugly was I find out what is the ResultSource of objects from
 330 that many to many pseudo relation.
 331
 332
 333 =head1 INTERFACE
 334
 335 =head1 METHODS
 336
 337 =head2 recursive_update
 338
 339 The method that does the work here.
 340
 341 =head2 is_m2m
 342
 343 $self->is_m2m( 'name ' ) - answers the question if 'name' is a many to many
 344 (pseudo) relation on $self.
 345
 346 =head2 get_m2m_source
 347
 348 $self->get_m2m_source( 'name' ) - returns the ResultSource linked to by the many
 349 to many (pseudo) relation 'name' from $self.
 350
 351
 352 =head1 DIAGNOSTICS
 353
 354
 355 =head1 CONFIGURATION AND ENVIRONMENT
 356
 357 DBIx::Class::RecursiveUpdate requires no configuration files or environment variables.
 358
 359 =head1 DEPENDENCIES
 360
 361     DBIx::Class
 362
 363 =head1 INCOMPATIBILITIES
 364
 365 =for author to fill in:
 366
 367 None reported.
 368
 369
 370 =head1 BUGS AND LIMITATIONS
 371
 372 =for author to fill in:
 373
 374 No bugs have been reported.
 375
 376 Please report any bugs or feature requests to
 377 C<bug-dbix-class-recursiveput@rt.cpan.org>, or through the web interface at
 378 L<http://rt.cpan.org>.
 379
 380
 381 =head1 AUTHOR
 382
 383 Zbigniew Lukasiak  C<< <zby@cpan.org> >>
 384 Influenced by code by Pedro Melo.
 385
 386 =head1 LICENCE AND COPYRIGHT
 387
 388 Copyright (c) 2008, Zbigniew Lukasiak C<< <zby@cpan.org> >>. All rights reserved.
 389
 390 This module is free software; you can redistribute it and/or
 391 modify it under the same terms as Perl itself. See L<perlartistic>.
 392
 393
 394 =head1 DISCLAIMER OF WARRANTY
 395
 396 BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
 397 FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
 398 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
 399 PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
 400 EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 401 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
 402 ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
 403 YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
 404 NECESSARY SERVICING, REPAIR, OR CORRECTION.
 405
 406 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
 407 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
 408 REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
 409 LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
 410 OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
 411 THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
 412 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
 413 FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
 414 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
 415 SUCH DAMAGES.