Commit | Line | Data |
996be9ee |
1 | package DBIx::Class::Schema::Loader::RelBuilder; |
2 | |
3 | use strict; |
4 | use warnings; |
7824616e |
5 | use Class::C3; |
fa994d3c |
6 | use Carp::Clan qw/^DBIx::Class/; |
996be9ee |
7 | use Lingua::EN::Inflect::Number (); |
8 | |
e42ec4ef |
9 | our $VERSION = '0.05003'; |
32f784fc |
10 | |
996be9ee |
11 | =head1 NAME |
12 | |
13 | DBIx::Class::Schema::Loader::RelBuilder - Builds relationships for DBIx::Class::Schema::Loader |
14 | |
15 | =head1 SYNOPSIS |
16 | |
17 | See L<DBIx::Class::Schema::Loader> |
18 | |
19 | =head1 DESCRIPTION |
20 | |
21 | This class builds relationships for L<DBIx::Class::Schema::Loader>. This |
22 | is module is not (yet) for external use. |
23 | |
24 | =head1 METHODS |
25 | |
26 | =head2 new |
27 | |
e8ad6491 |
28 | Arguments: schema_class (scalar), inflect_plural, inflect_singular |
996be9ee |
29 | |
30 | C<$schema_class> should be a schema class name, where the source |
31 | classes have already been set up and registered. Column info, primary |
32 | key, and unique constraints will be drawn from this schema for all |
33 | of the existing source monikers. |
34 | |
996be9ee |
35 | Options inflect_plural and inflect_singular are optional, and are better documented |
36 | in L<DBIx::Class::Schema::Loader::Base>. |
37 | |
38 | =head2 generate_code |
39 | |
e8ad6491 |
40 | Arguments: local_moniker (scalar), fk_info (arrayref) |
41 | |
42 | This generates the code for the relationships of a given table. |
43 | |
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: |
46 | |
47 | [ |
48 | { |
49 | local_columns => [ 'col2', 'col3' ], |
50 | remote_columns => [ 'col5', 'col7' ], |
51 | remote_moniker => 'AnotherTableMoniker', |
52 | }, |
53 | { |
54 | local_columns => [ 'col1', 'col4' ], |
55 | remote_columns => [ 'col1', 'col2' ], |
56 | remote_moniker => 'YetAnotherTableMoniker', |
57 | }, |
58 | # ... |
59 | ], |
60 | |
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 |
63 | arguments, like so: |
996be9ee |
64 | |
65 | { |
66 | 'Some::Source::Class' => [ |
b97c2c1e |
67 | { method => 'belongs_to', arguments => [ 'col1', 'Another::Source::Class' ], |
68 | { method => 'has_many', arguments => [ 'anothers', 'Yet::Another::Source::Class', 'col15' ], |
996be9ee |
69 | ], |
70 | 'Another::Source::Class' => [ |
71 | # ... |
72 | ], |
73 | # ... |
74 | } |
8f9d7ce5 |
75 | |
996be9ee |
76 | =cut |
77 | |
78 | sub new { |
c8c27020 |
79 | |
80 | my ( $class, $schema, $inflect_pl, $inflect_singular, $rel_attrs ) = @_; |
996be9ee |
81 | |
82 | my $self = { |
83 | schema => $schema, |
996be9ee |
84 | inflect_plural => $inflect_pl, |
85 | inflect_singular => $inflect_singular, |
c8c27020 |
86 | relationship_attrs => $rel_attrs, |
996be9ee |
87 | }; |
88 | |
c8c27020 |
89 | # validate the relationship_attrs arg |
90 | if( defined $self->{relationship_attrs} ) { |
91 | ref($self->{relationship_attrs}) eq 'HASH' |
92 | or croak "relationship_attrs must be a hashref"; |
93 | } |
996be9ee |
94 | |
c8c27020 |
95 | return bless $self => $class; |
996be9ee |
96 | } |
97 | |
98 | |
99 | # pluralize a relationship name |
100 | sub _inflect_plural { |
101 | my ($self, $relname) = @_; |
102 | |
103 | if( ref $self->{inflect_plural} eq 'HASH' ) { |
104 | return $self->{inflect_plural}->{$relname} |
105 | if exists $self->{inflect_plural}->{$relname}; |
106 | } |
107 | elsif( ref $self->{inflect_plural} eq 'CODE' ) { |
108 | my $inflected = $self->{inflect_plural}->($relname); |
109 | return $inflected if $inflected; |
110 | } |
111 | |
d3af7a07 |
112 | return Lingua::EN::Inflect::Number::to_PL($relname); |
996be9ee |
113 | } |
114 | |
115 | # Singularize a relationship name |
116 | sub _inflect_singular { |
117 | my ($self, $relname) = @_; |
118 | |
119 | if( ref $self->{inflect_singular} eq 'HASH' ) { |
120 | return $self->{inflect_singular}->{$relname} |
121 | if exists $self->{inflect_singular}->{$relname}; |
122 | } |
123 | elsif( ref $self->{inflect_singular} eq 'CODE' ) { |
124 | my $inflected = $self->{inflect_singular}->($relname); |
125 | return $inflected if $inflected; |
126 | } |
127 | |
d3af7a07 |
128 | return Lingua::EN::Inflect::Number::to_S($relname); |
996be9ee |
129 | } |
130 | |
c8c27020 |
131 | # accessor for options to be passed to each generated relationship |
132 | # type. take single argument, the relationship type name, and returns |
133 | # either a hashref (if some options are set), or nothing |
134 | sub _relationship_attrs { |
135 | my ( $self, $reltype ) = @_; |
136 | my $r = $self->{relationship_attrs}; |
137 | return unless $r && ( $r->{all} || $r->{$reltype} ); |
138 | |
139 | my %composite = %{ $r->{all} || {} }; |
140 | if( my $specific = $r->{$reltype} ) { |
141 | while( my ($k,$v) = each %$specific ) { |
142 | $composite{$k} = $v; |
143 | } |
144 | } |
145 | return \%composite; |
146 | } |
147 | |
26f1c8c9 |
148 | sub _array_eq { |
149 | my ($a, $b) = @_; |
150 | |
151 | return unless @$a == @$b; |
152 | |
153 | for (my $i = 0; $i < @$a; $i++) { |
154 | return unless $a->[$i] eq $b->[$i]; |
155 | } |
156 | return 1; |
157 | } |
158 | |
c39e403e |
159 | sub _remote_attrs { |
160 | my ($self, $local_moniker, $local_cols) = @_; |
161 | |
c8c27020 |
162 | # get our base set of attrs from _relationship_attrs, if present |
163 | my $attrs = $self->_relationship_attrs('belongs_to') || {}; |
164 | |
165 | # If the referring column is nullable, make 'belongs_to' an |
166 | # outer join, unless explicitly set by relationship_attrs |
c39e403e |
167 | my $nullable = grep { $self->{schema}->source($local_moniker)->column_info($_)->{is_nullable} } |
168 | @$local_cols; |
c8c27020 |
169 | $attrs->{join_type} = 'LEFT' |
170 | if $nullable && !defined $attrs->{join_type}; |
c39e403e |
171 | |
c8c27020 |
172 | return $attrs; |
c39e403e |
173 | } |
174 | |
f2fc8d01 |
175 | sub _remote_relname { |
176 | my ($self, $remote_table, $cond) = @_; |
177 | |
178 | my $remote_relname; |
179 | # for single-column case, set the remote relname to the column |
180 | # name, to make filter accessors work, but strip trailing _id |
181 | if(scalar keys %{$cond} == 1) { |
182 | my ($col) = values %{$cond}; |
183 | $col =~ s/_id$//; |
184 | $remote_relname = $self->_inflect_singular($col); |
185 | } |
186 | else { |
187 | $remote_relname = $self->_inflect_singular(lc $remote_table); |
188 | } |
189 | |
190 | return $remote_relname; |
191 | } |
192 | |
996be9ee |
193 | sub generate_code { |
26f1c8c9 |
194 | my ($self, $local_moniker, $rels, $uniqs) = @_; |
996be9ee |
195 | |
196 | my $all_code = {}; |
197 | |
e8ad6491 |
198 | my $local_class = $self->{schema}->class($local_moniker); |
057fbb08 |
199 | |
e8ad6491 |
200 | my %counters; |
201 | foreach my $rel (@$rels) { |
202 | next if !$rel->{remote_source}; |
203 | $counters{$rel->{remote_source}}++; |
204 | } |
205 | |
206 | foreach my $rel (@$rels) { |
057fbb08 |
207 | my $remote_moniker = $rel->{remote_source} |
208 | or next; |
209 | |
210 | my $remote_class = $self->{schema}->class($remote_moniker); |
211 | my $remote_obj = $self->{schema}->source($remote_moniker); |
212 | my $remote_cols = $rel->{remote_columns} || [ $remote_obj->primary_columns ]; |
213 | |
214 | my $local_cols = $rel->{local_columns}; |
e8ad6491 |
215 | |
216 | if($#$local_cols != $#$remote_cols) { |
217 | croak "Column count mismatch: $local_moniker (@$local_cols) " |
218 | . "$remote_moniker (@$remote_cols)"; |
996be9ee |
219 | } |
220 | |
e8ad6491 |
221 | my %cond; |
222 | foreach my $i (0 .. $#$local_cols) { |
223 | $cond{$remote_cols->[$i]} = $local_cols->[$i]; |
224 | } |
996be9ee |
225 | |
057fbb08 |
226 | my ( $local_relname, $remote_relname, $remote_method ) = |
227 | $self->_relnames_and_methods( $local_moniker, $rel, \%cond, $uniqs, \%counters ); |
7dba7c70 |
228 | |
e8ad6491 |
229 | push(@{$all_code->{$local_class}}, |
230 | { method => 'belongs_to', |
231 | args => [ $remote_relname, |
232 | $remote_class, |
233 | \%cond, |
c39e403e |
234 | $self->_remote_attrs($local_moniker, $local_cols), |
e8ad6491 |
235 | ], |
996be9ee |
236 | } |
e8ad6491 |
237 | ); |
238 | |
057fbb08 |
239 | my %rev_cond = reverse %cond; |
240 | for (keys %rev_cond) { |
241 | $rev_cond{"foreign.$_"} = "self.".$rev_cond{$_}; |
242 | delete $rev_cond{$_}; |
243 | } |
244 | |
e8ad6491 |
245 | push(@{$all_code->{$remote_class}}, |
26f1c8c9 |
246 | { method => $remote_method, |
e8ad6491 |
247 | args => [ $local_relname, |
248 | $local_class, |
249 | \%rev_cond, |
c8c27020 |
250 | $self->_relationship_attrs($remote_method), |
e8ad6491 |
251 | ], |
252 | } |
253 | ); |
996be9ee |
254 | } |
255 | |
256 | return $all_code; |
257 | } |
258 | |
057fbb08 |
259 | sub _relnames_and_methods { |
260 | my ( $self, $local_moniker, $rel, $cond, $uniqs, $counters ) = @_; |
e9c09ed9 |
261 | |
057fbb08 |
262 | my $remote_moniker = $rel->{remote_source}; |
263 | my $remote_obj = $self->{schema}->source( $remote_moniker ); |
264 | my $remote_class = $self->{schema}->class( $remote_moniker ); |
265 | my $remote_relname = $self->_remote_relname( $remote_obj->from, $cond); |
fa6f8d4e |
266 | |
057fbb08 |
267 | my $local_cols = $rel->{local_columns}; |
268 | my $local_table = $self->{schema}->source($local_moniker)->from; |
269 | |
270 | # If more than one rel between this pair of tables, use the local |
271 | # col names to distinguish |
272 | my $local_relname; |
684f9580 |
273 | my $old_multirel_name; #< TODO: remove me |
057fbb08 |
274 | if ( $counters->{$remote_moniker} > 1) { |
275 | my $colnames = q{_} . join(q{_}, @$local_cols); |
276 | $remote_relname .= $colnames if keys %$cond > 1; |
277 | |
ff098bf3 |
278 | $local_relname = lc($local_table) . $colnames; |
684f9580 |
279 | $local_relname =~ s/_id$// |
280 | #< TODO: remove me |
281 | and $old_multirel_name = $self->_inflect_plural( lc($local_table) . $colnames ); |
057fbb08 |
282 | $local_relname = $self->_inflect_plural( $local_relname ); |
283 | |
057fbb08 |
284 | } else { |
285 | $local_relname = $self->_inflect_plural(lc $local_table); |
286 | } |
fa6f8d4e |
287 | |
057fbb08 |
288 | my $remote_method = 'has_many'; |
289 | |
290 | # If the local columns have a UNIQUE constraint, this is a one-to-one rel |
291 | my $local_source = $self->{schema}->source($local_moniker); |
292 | if (_array_eq([ $local_source->primary_columns ], $local_cols) || |
293 | grep { _array_eq($_->[1], $local_cols) } @$uniqs) { |
294 | $remote_method = 'might_have'; |
295 | $local_relname = $self->_inflect_singular($local_relname); |
296 | } |
fa6f8d4e |
297 | |
298 | # TODO: remove me after 0.05003 release |
684f9580 |
299 | $old_multirel_name |
300 | and warn __PACKAGE__." $VERSION: warning, stripping trailing _id from ${remote_class} relation '$old_multirel_name', renaming to '$local_relname'. This behavior is new as of 0.05003.\n"; |
fa6f8d4e |
301 | |
057fbb08 |
302 | return ( $local_relname, $remote_relname, $remote_method ); |
fa6f8d4e |
303 | } |
304 | |
be80bba7 |
305 | =head1 AUTHOR |
306 | |
9cc8e7e1 |
307 | See L<DBIx::Class::Schema::Loader/AUTHOR> and L<DBIx::Class::Schema::Loader/CONTRIBUTORS>. |
be80bba7 |
308 | |
309 | =head1 LICENSE |
310 | |
311 | This library is free software; you can redistribute it and/or modify it under |
312 | the same terms as Perl itself. |
313 | |
314 | =cut |
315 | |
996be9ee |
316 | 1; |