1 package DBIx::Class::Schema::Loader::RelBuilder;
5 use base 'Class::Accessor::Grouped';
7 use Carp::Clan qw/^DBIx::Class/;
8 use Scalar::Util 'weaken';
9 use Lingua::EN::Inflect::Phrase ();
10 use DBIx::Class::Schema::Loader::Utils 'split_name';
11 use File::Slurp 'slurp';
14 use List::MoreUtils 'apply';
17 our $VERSION = '0.07002';
21 DBIx::Class::Schema::Loader::RelBuilder - Builds relationships for DBIx::Class::Schema::Loader
25 See L<DBIx::Class::Schema::Loader> and L<DBIx::Class::Schema::Loader::Base>.
29 This class builds relationships for L<DBIx::Class::Schema::Loader>. This
30 is module is not (yet) for external use.
36 Arguments: $base object
40 Arguments: local_moniker (scalar), fk_info (arrayref)
42 This generates the code for the relationships of a given table.
44 C<local_moniker> is the moniker name of the table which had the REFERENCES
45 statements. The fk_info arrayref's contents should take the form:
49 local_columns => [ 'col2', 'col3' ],
50 remote_columns => [ 'col5', 'col7' ],
51 remote_moniker => 'AnotherTableMoniker',
54 local_columns => [ 'col1', 'col4' ],
55 remote_columns => [ 'col1', 'col2' ],
56 remote_moniker => 'YetAnotherTableMoniker',
61 This method will return the generated relationships as a hashref keyed on the
62 class names. The values are arrayrefs of hashes containing method name and
66 'Some::Source::Class' => [
67 { method => 'belongs_to', arguments => [ 'col1', 'Another::Source::Class' ],
68 { method => 'has_many', arguments => [ 'anothers', 'Yet::Another::Source::Class', 'col15' ],
70 'Another::Source::Class' => [
78 __PACKAGE__->mk_group_accessors('simple', qw/
88 my ( $class, $base ) = @_;
90 # from old POD about this constructor:
91 # C<$schema_class> should be a schema class name, where the source
92 # classes have already been set up and registered. Column info,
93 # primary key, and unique constraints will be drawn from this
94 # schema for all of the existing source monikers.
96 # Options inflect_plural and inflect_singular are optional, and
97 # are better documented in L<DBIx::Class::Schema::Loader::Base>.
101 schema => $base->schema,
102 inflect_plural => $base->inflect_plural,
103 inflect_singular => $base->inflect_singular,
104 relationship_attrs => $base->relationship_attrs,
108 weaken $self->{base}; #< don't leak
110 bless $self => $class;
112 # validate the relationship_attrs arg
113 if( defined $self->relationship_attrs ) {
114 ref $self->relationship_attrs eq 'HASH'
115 or croak "relationship_attrs must be a hashref";
122 # pluralize a relationship name
123 sub _inflect_plural {
124 my ($self, $relname) = @_;
126 return '' if !defined $relname || $relname eq '';
128 if( ref $self->inflect_plural eq 'HASH' ) {
129 return $self->inflect_plural->{$relname}
130 if exists $self->inflect_plural->{$relname};
132 elsif( ref $self->inflect_plural eq 'CODE' ) {
133 my $inflected = $self->inflect_plural->($relname);
134 return $inflected if $inflected;
137 return $self->_to_PL($relname);
140 # Singularize a relationship name
141 sub _inflect_singular {
142 my ($self, $relname) = @_;
144 return '' if !defined $relname || $relname eq '';
146 if( ref $self->inflect_singular eq 'HASH' ) {
147 return $self->inflect_singular->{$relname}
148 if exists $self->inflect_singular->{$relname};
150 elsif( ref $self->inflect_singular eq 'CODE' ) {
151 my $inflected = $self->inflect_singular->($relname);
152 return $inflected if $inflected;
155 return $self->_to_S($relname);
159 my ($self, $name) = @_;
162 my $plural = Lingua::EN::Inflect::Phrase::to_PL($name);
169 my ($self, $name) = @_;
172 my $singular = Lingua::EN::Inflect::Phrase::to_S($name);
173 $singular =~ s/ /_/g;
178 sub _default_relationship_attrs { +{
188 on_delete => 'CASCADE',
189 on_update => 'CASCADE',
194 # accessor for options to be passed to each generated relationship
195 # type. take single argument, the relationship type name, and returns
196 # either a hashref (if some options are set), or nothing
197 sub _relationship_attrs {
198 my ( $self, $reltype ) = @_;
199 my $r = $self->relationship_attrs;
202 %{ $self->_default_relationship_attrs->{$reltype} || {} },
206 if( my $specific = $r->{$reltype} ) {
207 while( my ($k,$v) = each %$specific ) {
215 my ($self, $a, $b) = @_;
217 return unless @$a == @$b;
219 for (my $i = 0; $i < @$a; $i++) {
220 return unless $a->[$i] eq $b->[$i];
226 my ($self, $local_moniker, $local_cols) = @_;
228 # get our base set of attrs from _relationship_attrs, if present
229 my $attrs = $self->_relationship_attrs('belongs_to') || {};
231 # If the referring column is nullable, make 'belongs_to' an
232 # outer join, unless explicitly set by relationship_attrs
233 my $nullable = grep { $self->schema->source($local_moniker)->column_info($_)->{is_nullable} } @$local_cols;
234 $attrs->{join_type} = 'LEFT' if $nullable && !defined $attrs->{join_type};
240 my ($self, $name) = @_;
243 # scalar ref for weird table name (like one containing a '.')
244 ($name = $$name) =~ s/\W+/_/g;
247 # remove 'schema.' prefix if any
248 $name =~ s/^[^.]+\.//;
254 sub _normalize_name {
255 my ($self, $name) = @_;
257 $name = $self->_sanitize_name($name);
259 my @words = split_name $name;
261 return join '_', map lc, @words;
264 sub _remote_relname {
265 my ($self, $remote_table, $cond) = @_;
268 # for single-column case, set the remote relname to the column
269 # name, to make filter accessors work, but strip trailing _id
270 if(scalar keys %{$cond} == 1) {
271 my ($col) = values %{$cond};
272 $col = $self->_normalize_name($col);
274 $remote_relname = $self->_inflect_singular($col);
277 $remote_relname = $self->_inflect_singular($self->_normalize_name($remote_table));
280 return $remote_relname;
284 my ($self, $local_moniker, $rels, $uniqs) = @_;
288 my $local_class = $self->schema->class($local_moniker);
291 foreach my $rel (@$rels) {
292 next if !$rel->{remote_source};
293 $counters{$rel->{remote_source}}++;
296 foreach my $rel (@$rels) {
297 my $remote_moniker = $rel->{remote_source}
300 my $remote_class = $self->schema->class($remote_moniker);
301 my $remote_obj = $self->schema->source($remote_moniker);
302 my $remote_cols = $rel->{remote_columns} || [ $remote_obj->primary_columns ];
304 my $local_cols = $rel->{local_columns};
306 if($#$local_cols != $#$remote_cols) {
307 croak "Column count mismatch: $local_moniker (@$local_cols) "
308 . "$remote_moniker (@$remote_cols)";
312 foreach my $i (0 .. $#$local_cols) {
313 $cond{$remote_cols->[$i]} = $local_cols->[$i];
316 my ( $local_relname, $remote_relname, $remote_method ) =
317 $self->_relnames_and_method( $local_moniker, $rel, \%cond, $uniqs, \%counters );
319 push(@{$all_code->{$local_class}},
320 { method => 'belongs_to',
321 args => [ $remote_relname,
324 $self->_remote_attrs($local_moniker, $local_cols),
329 my %rev_cond = reverse %cond;
330 for (keys %rev_cond) {
331 $rev_cond{"foreign.$_"} = "self.".$rev_cond{$_};
332 delete $rev_cond{$_};
335 push(@{$all_code->{$remote_class}},
336 { method => $remote_method,
337 args => [ $local_relname,
340 $self->_relationship_attrs($remote_method),
349 sub _relnames_and_method {
350 my ( $self, $local_moniker, $rel, $cond, $uniqs, $counters ) = @_;
352 my $remote_moniker = $rel->{remote_source};
353 my $remote_obj = $self->schema->source( $remote_moniker );
354 my $remote_class = $self->schema->class( $remote_moniker );
355 my $remote_relname = $self->_remote_relname( $remote_obj->from, $cond);
357 my $local_cols = $rel->{local_columns};
358 my $local_table = $self->schema->source($local_moniker)->from;
359 my $local_class = $self->schema->class($local_moniker);
360 my $local_source = $self->schema->source($local_moniker);
362 my $local_relname_uninflected = $self->_normalize_name($local_table);
363 my $local_relname = $self->_inflect_plural($self->_normalize_name($local_table));
365 my $remote_method = 'has_many';
367 # If the local columns have a UNIQUE constraint, this is a one-to-one rel
368 if ($self->_array_eq([ $local_source->primary_columns ], $local_cols) ||
369 grep { $self->_array_eq($_->[1], $local_cols) } @$uniqs) {
370 $remote_method = 'might_have';
371 $local_relname = $self->_inflect_singular($local_relname_uninflected);
374 # If more than one rel between this pair of tables, use the local
375 # col names to distinguish, unless the rel was created previously.
376 if ($counters->{$remote_moniker} > 1) {
377 my $relationship_exists = 0;
379 if (-f (my $existing_remote_file = $self->{base}->get_dump_filename($remote_class))) {
380 my $class = "${remote_class}Temporary";
382 if (not do { no strict 'refs'; %{$class . '::'} }) {
383 my $code = slurp $existing_remote_file;
385 $code =~ s/(?<=package $remote_class)/Temporary/g;
387 $code =~ s/__PACKAGE__->meta->make_immutable;//g;
392 push @{ $self->_temp_classes }, $class;
395 if ($class->has_relationship($local_relname)) {
396 my $rel_cols = [ sort { $a cmp $b } apply { s/^foreign\.//i }
397 (keys %{ $class->relationship_info($local_relname)->{cond} }) ];
399 $relationship_exists = 1 if $self->_array_eq([ sort @$local_cols ], $rel_cols);
403 if (not $relationship_exists) {
404 my $colnames = q{_} . $self->_normalize_name(join '_', @$local_cols);
405 $remote_relname .= $colnames if keys %$cond > 1;
407 $local_relname = $self->_normalize_name($local_table . $colnames);
408 $local_relname =~ s/_id$//;
410 $local_relname_uninflected = $local_relname;
411 $local_relname = $self->_inflect_plural($local_relname);
413 # if colnames were added and this is a might_have, re-inflect
414 if ($remote_method eq 'might_have') {
415 $local_relname = $self->_inflect_singular($local_relname_uninflected);
420 return ( $local_relname, $remote_relname, $remote_method );
426 for my $class (@{ $self->_temp_classes }) {
427 Class::Unload->unload($class);
430 $self->_temp_classes([]);
435 See L<DBIx::Class::Schema::Loader/AUTHOR> and L<DBIx::Class::Schema::Loader/CONTRIBUTORS>.
439 This library is free software; you can redistribute it and/or modify it under
440 the same terms as Perl itself.
445 # vim:et sts=4 sw=4 tw=0: