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1 | package DBIx::Class::Relationship::Base; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | |
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6 | use base qw/DBIx::Class/; |
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7 | |
8 | use Scalar::Util qw/weaken blessed/; |
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9 | use Try::Tiny; |
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10 | use DBIx::Class::_Util 'UNRESOLVABLE_CONDITION'; |
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11 | use namespace::clean; |
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12 | |
75d07914 |
13 | =head1 NAME |
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14 | |
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15 | DBIx::Class::Relationship::Base - Inter-table relationships |
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16 | |
17 | =head1 SYNOPSIS |
18 | |
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19 | __PACKAGE__->add_relationship( |
20 | spiders => 'My::DB::Result::Creatures', |
21 | sub { |
22 | my $args = shift; |
23 | return { |
24 | "$args->{foreign_alias}.id" => { -ident => "$args->{self_alias}.id" }, |
25 | "$args->{foreign_alias}.type" => 'arachnid' |
26 | }; |
27 | }, |
28 | ); |
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29 | |
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30 | =head1 DESCRIPTION |
31 | |
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32 | This class provides methods to describe the relationships between the |
33 | tables in your database model. These are the "bare bones" relationships |
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34 | methods, for predefined ones, look in L<DBIx::Class::Relationship>. |
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35 | |
36 | =head1 METHODS |
37 | |
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38 | =head2 add_relationship |
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39 | |
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40 | =over 4 |
41 | |
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42 | =item Arguments: $rel_name, $foreign_class, $condition, $attrs |
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43 | |
44 | =back |
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45 | |
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46 | __PACKAGE__->add_relationship('rel_name', |
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47 | 'Foreign::Class', |
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48 | $condition, $attrs); |
49 | |
50 | Create a custom relationship between one result source and another |
51 | source, indicated by its class name. |
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52 | |
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53 | =head3 condition |
54 | |
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55 | The condition argument describes the C<ON> clause of the C<JOIN> |
56 | expression used to connect the two sources when creating SQL queries. |
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57 | |
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58 | =head4 Simple equality |
59 | |
60 | To create simple equality joins, supply a hashref containing the remote |
61 | table column name as the key(s) prefixed by C<'foreign.'>, and the |
62 | corresponding local table column name as the value(s) prefixed by C<'self.'>. |
63 | Both C<foreign> and C<self> are pseudo aliases and must be entered |
64 | literally. They will be replaced with the actual correct table alias |
65 | when the SQL is produced. |
66 | |
67 | For example given: |
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68 | |
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69 | My::Schema::Author->has_many( |
70 | books => 'My::Schema::Book', |
71 | { 'foreign.author_id' => 'self.id' } |
72 | ); |
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73 | |
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74 | A query like: |
75 | |
76 | $author_rs->search_related('books')->next |
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77 | |
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78 | will result in the following C<JOIN> clause: |
79 | |
80 | ... FROM author me LEFT JOIN book books ON books.author_id = me.id ... |
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81 | |
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82 | This describes a relationship between the C<Author> table and the |
83 | C<Book> table where the C<Book> table has a column C<author_id> |
84 | containing the ID value of the C<Author>. |
85 | |
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86 | Similarly: |
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87 | |
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88 | My::Schema::Book->has_many( |
89 | editions => 'My::Schema::Edition', |
90 | { |
91 | 'foreign.publisher_id' => 'self.publisher_id', |
92 | 'foreign.type_id' => 'self.type_id', |
93 | } |
94 | ); |
95 | |
96 | ... |
97 | |
98 | $book_rs->search_related('editions')->next |
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99 | |
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100 | will result in the C<JOIN> clause: |
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101 | |
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102 | ... FROM book me |
103 | LEFT JOIN edition editions ON |
104 | editions.publisher_id = me.publisher_id |
105 | AND editions.type_id = me.type_id ... |
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106 | |
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107 | This describes the relationship from C<Book> to C<Edition>, where the |
108 | C<Edition> table refers to a publisher and a type (e.g. "paperback"): |
109 | |
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110 | =head4 Multiple groups of simple equality conditions |
111 | |
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112 | As is the default in L<SQL::Abstract>, the key-value pairs will be |
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113 | C<AND>ed in the resulting C<JOIN> clause. An C<OR> can be achieved with |
114 | an arrayref. For example a condition like: |
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115 | |
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116 | My::Schema::Item->has_many( |
117 | related_item_links => My::Schema::Item::Links, |
118 | [ |
119 | { 'foreign.left_itemid' => 'self.id' }, |
120 | { 'foreign.right_itemid' => 'self.id' }, |
121 | ], |
122 | ); |
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123 | |
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124 | will translate to the following C<JOIN> clause: |
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125 | |
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126 | ... FROM item me JOIN item_relations related_item_links ON |
127 | related_item_links.left_itemid = me.id |
128 | OR related_item_links.right_itemid = me.id ... |
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129 | |
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130 | This describes the relationship from C<Item> to C<Item::Links>, where |
131 | C<Item::Links> is a many-to-many linking table, linking items back to |
132 | themselves in a peer fashion (without a "parent-child" designation) |
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133 | |
84d8c2ad |
134 | =head4 Custom join conditions |
135 | |
5d2588cc |
136 | NOTE: The custom join condition specification mechanism is capable of |
137 | generating JOIN clauses of virtually unlimited complexity. This may limit |
138 | your ability to traverse some of the more involved relationship chains the |
139 | way you expect, *and* may bring your RDBMS to its knees. Exercise care |
140 | when declaring relationships as described here. |
141 | |
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142 | To specify joins which describe more than a simple equality of column |
143 | values, the custom join condition coderef syntax can be used. For |
144 | example: |
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145 | |
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146 | My::Schema::Artist->has_many( |
147 | cds_80s => 'My::Schema::CD', |
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148 | sub { |
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149 | my $args = shift; |
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150 | |
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151 | return { |
152 | "$args->{foreign_alias}.artist" => { -ident => "$args->{self_alias}.artistid" }, |
153 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
154 | }; |
155 | } |
156 | ); |
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157 | |
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158 | ... |
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159 | |
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160 | $artist_rs->search_related('cds_80s')->next; |
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161 | |
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162 | will result in the C<JOIN> clause: |
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163 | |
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164 | ... FROM artist me LEFT JOIN cd cds_80s ON |
165 | cds_80s.artist = me.artistid |
166 | AND cds_80s.year < ? |
167 | AND cds_80s.year > ? |
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168 | |
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169 | with the bind values: |
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170 | |
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171 | '1990', '1979' |
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172 | |
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173 | C<< $args->{foreign_alias} >> and C<< $args->{self_alias} >> are supplied the |
174 | same values that would be otherwise substituted for C<foreign> and C<self> |
175 | in the simple hashref syntax case. |
176 | |
177 | The coderef is expected to return a valid L<SQL::Abstract> query-structure, just |
178 | like what one would supply as the first argument to |
179 | L<DBIx::Class::ResultSet/search>. The return value will be passed directly to |
180 | L<SQL::Abstract> and the resulting SQL will be used verbatim as the C<ON> |
181 | clause of the C<JOIN> statement associated with this relationship. |
182 | |
183 | While every coderef-based condition must return a valid C<ON> clause, it may |
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184 | elect to additionally return a simplified B<optional> join-free condition |
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185 | consisting of a hashref with B<all keys being fully qualified names of columns |
186 | declared on the corresponding result source>. This boils down to two scenarios: |
187 | |
188 | =over |
189 | |
190 | =item * |
191 | |
192 | When relationship resolution is invoked after C<< $result->$rel_name >>, as |
193 | opposed to C<< $rs->related_resultset($rel_name) >>, the C<$result> object |
194 | is passed to the coderef as C<< $args->{self_result_object} >>. |
195 | |
196 | =item * |
197 | |
198 | Alternatively when the user-space invokes resolution via |
199 | C<< $result->set_from_related( $rel_name => $foreign_values_or_object ) >>, the |
200 | corresponding data is passed to the coderef as C<< $args->{foreign_values} >>, |
201 | B<always> in the form of a hashref. If a foreign result object is supplied |
202 | (which is valid usage of L</set_from_related>), its values will be extracted |
203 | into hashref form by calling L<get_columns|DBIx::Class::Row/get_columns>. |
204 | |
205 | =back |
206 | |
207 | Note that the above scenarios are mutually exclusive, that is you will be supplied |
208 | none or only one of C<self_result_object> and C<foreign_values>. In other words if |
209 | you define your condition coderef as: |
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210 | |
211 | sub { |
212 | my $args = shift; |
213 | |
214 | return ( |
215 | { |
216 | "$args->{foreign_alias}.artist" => { -ident => "$args->{self_alias}.artistid" }, |
217 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
218 | }, |
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219 | ! $args->{self_result_object} ? () : { |
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220 | "$args->{foreign_alias}.artist" => $args->{self_result_object}->artistid, |
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221 | "$args->{foreign_alias}.year" => { '>', "1979", '<', "1990" }, |
222 | }, |
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223 | ! $args->{foreign_values} ? () : { |
224 | "$args->{self_alias}.artistid" => $args->{foreign_values}{artist}, |
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225 | } |
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226 | ); |
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227 | } |
228 | |
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229 | Then this code: |
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230 | |
231 | my $artist = $schema->resultset("Artist")->find({ id => 4 }); |
232 | $artist->cds_80s->all; |
233 | |
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234 | Can skip a C<JOIN> altogether and instead produce: |
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235 | |
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236 | SELECT cds_80s.cdid, cds_80s.artist, cds_80s.title, cds_80s.year, cds_80s.genreid, cds_80s.single_track |
237 | FROM cd cds_80s |
238 | WHERE cds_80s.artist = ? |
239 | AND cds_80s.year < ? |
240 | AND cds_80s.year > ? |
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241 | |
242 | With the bind values: |
243 | |
244 | '4', '1990', '1979' |
245 | |
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246 | While this code: |
247 | |
248 | my $cd = $schema->resultset("CD")->search({ artist => 1 }, { rows => 1 })->single; |
249 | my $artist = $schema->resultset("Artist")->new({}); |
250 | $artist->set_from_related('cds_80s'); |
251 | |
252 | Will properly set the C<< $artist->artistid >> field of this new object to C<1> |
253 | |
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254 | Note that in order to be able to use L</set_from_related> (and by extension |
255 | L<< $result->create_related|DBIx::Class::Relationship::Base/create_related >>), |
256 | the returned join free condition B<must> contain only plain values/deflatable |
257 | objects. For instance the C<year> constraint in the above example prevents |
258 | the relationship from being used to create related objects using |
259 | C<< $artst->create_related( cds_80s => { title => 'blah' } ) >> (an |
260 | exception will be thrown). |
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261 | |
262 | In order to allow the user to go truly crazy when generating a custom C<ON> |
263 | clause, the C<$args> hashref passed to the subroutine contains some extra |
264 | metadata. Currently the supplied coderef is executed as: |
265 | |
266 | $relationship_info->{cond}->({ |
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267 | self_resultsource => The resultsource instance on which rel_name is registered |
268 | rel_name => The relationship name (does *NOT* always match foreign_alias) |
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269 | |
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270 | self_alias => The alias of the invoking resultset |
271 | foreign_alias => The alias of the to-be-joined resultset (does *NOT* always match rel_name) |
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272 | |
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273 | # only one of these (or none at all) will ever be supplied to aid in the |
274 | # construction of a join-free condition |
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275 | |
276 | self_result_object => The invocant *object* itself in case of a call like |
277 | $result_object->$rel_name( ... ) |
278 | |
279 | foreign_values => A *hashref* of related data: may be passed in directly or |
280 | derived via ->get_columns() from a related object in case of |
281 | $result_object->set_from_related( $rel_name, $foreign_result_object ) |
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282 | |
283 | # deprecated inconsistent names, will be forever available for legacy code |
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284 | self_rowobj => Old deprecated slot for self_result_object |
285 | foreign_relname => Old deprecated slot for rel_name |
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286 | }); |
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287 | |
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288 | =head3 attributes |
289 | |
290 | The L<standard ResultSet attributes|DBIx::Class::ResultSet/ATTRIBUTES> may |
291 | be used as relationship attributes. In particular, the 'where' attribute is |
292 | useful for filtering relationships: |
293 | |
294 | __PACKAGE__->has_many( 'valid_users', 'MyApp::Schema::User', |
295 | { 'foreign.user_id' => 'self.user_id' }, |
296 | { where => { valid => 1 } } |
297 | ); |
298 | |
299 | The following attributes are also valid: |
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300 | |
301 | =over 4 |
302 | |
303 | =item join_type |
304 | |
305 | Explicitly specifies the type of join to use in the relationship. Any SQL |
306 | join type is valid, e.g. C<LEFT> or C<RIGHT>. It will be placed in the SQL |
307 | command immediately before C<JOIN>. |
308 | |
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309 | =item proxy =E<gt> $column | \@columns | \%column |
310 | |
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311 | The 'proxy' attribute can be used to retrieve values, and to perform |
312 | updates if the relationship has 'cascade_update' set. The 'might_have' |
313 | and 'has_one' relationships have this set by default; if you want a proxy |
314 | to update across a 'belongs_to' relationship, you must set the attribute |
315 | yourself. |
316 | |
97c96475 |
317 | =over 4 |
318 | |
319 | =item \@columns |
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320 | |
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321 | An arrayref containing a list of accessors in the foreign class to create in |
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322 | the main class. If, for example, you do the following: |
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323 | |
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324 | MyApp::Schema::CD->might_have(liner_notes => 'MyApp::Schema::LinerNotes', |
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325 | undef, { |
326 | proxy => [ qw/notes/ ], |
327 | }); |
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328 | |
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329 | Then, assuming MyApp::Schema::LinerNotes has an accessor named notes, you can do: |
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330 | |
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331 | my $cd = MyApp::Schema::CD->find(1); |
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332 | $cd->notes('Notes go here'); # set notes -- LinerNotes object is |
333 | # created if it doesn't exist |
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334 | |
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335 | For a 'belongs_to relationship, note the 'cascade_update': |
336 | |
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337 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd, |
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338 | { proxy => ['title'], cascade_update => 1 } |
339 | ); |
340 | $track->title('New Title'); |
341 | $track->update; # updates title in CD |
342 | |
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343 | =item \%column |
344 | |
345 | A hashref where each key is the accessor you want installed in the main class, |
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346 | and its value is the name of the original in the foreign class. |
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347 | |
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348 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', { |
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349 | proxy => { cd_title => 'title' }, |
350 | }); |
351 | |
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352 | This will create an accessor named C<cd_title> on the C<$track> result object. |
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353 | |
354 | =back |
355 | |
356 | NOTE: you can pass a nested struct too, for example: |
357 | |
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358 | MyApp::Schema::Track->belongs_to( cd => 'MyApp::Schema::CD', 'cd', { |
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359 | proxy => [ 'year', { cd_title => 'title' } ], |
360 | }); |
361 | |
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362 | =item accessor |
363 | |
364 | Specifies the type of accessor that should be created for the relationship. |
365 | Valid values are C<single> (for when there is only a single related object), |
366 | C<multi> (when there can be many), and C<filter> (for when there is a single |
367 | related object, but you also want the relationship accessor to double as |
368 | a column accessor). For C<multi> accessors, an add_to_* method is also |
369 | created, which calls C<create_related> for the relationship. |
370 | |
3d618782 |
371 | =item is_foreign_key_constraint |
372 | |
373 | If you are using L<SQL::Translator> to create SQL for you and you find that it |
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374 | is creating constraints where it shouldn't, or not creating them where it |
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375 | should, set this attribute to a true or false value to override the detection |
376 | of when to create constraints. |
377 | |
5f7ac523 |
378 | =item cascade_copy |
379 | |
380 | If C<cascade_copy> is true on a C<has_many> relationship for an |
381 | object, then when you copy the object all the related objects will |
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382 | be copied too. To turn this behaviour off, pass C<< cascade_copy => 0 >> |
383 | in the C<$attr> hashref. |
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384 | |
385 | The behaviour defaults to C<< cascade_copy => 1 >> for C<has_many> |
386 | relationships. |
5f7ac523 |
387 | |
388 | =item cascade_delete |
389 | |
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390 | By default, DBIx::Class cascades deletes across C<has_many>, |
391 | C<has_one> and C<might_have> relationships. You can disable this |
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392 | behaviour on a per-relationship basis by supplying |
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393 | C<< cascade_delete => 0 >> in the relationship attributes. |
5f7ac523 |
394 | |
395 | The cascaded operations are performed after the requested delete, |
396 | so if your database has a constraint on the relationship, it will |
397 | have deleted/updated the related records or raised an exception |
398 | before DBIx::Class gets to perform the cascaded operation. |
399 | |
400 | =item cascade_update |
401 | |
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402 | By default, DBIx::Class cascades updates across C<has_one> and |
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403 | C<might_have> relationships. You can disable this behaviour on a |
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404 | per-relationship basis by supplying C<< cascade_update => 0 >> in |
405 | the relationship attributes. |
5f7ac523 |
406 | |
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407 | The C<belongs_to> relationship does not update across relationships |
408 | by default, so if you have a 'proxy' attribute on a belongs_to and want to |
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409 | use 'update' on it, you must set C<< cascade_update => 1 >>. |
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410 | |
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411 | This is not a RDMS style cascade update - it purely means that when |
412 | an object has update called on it, all the related objects also |
413 | have update called. It will not change foreign keys automatically - |
414 | you must arrange to do this yourself. |
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415 | |
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416 | =item on_delete / on_update |
417 | |
418 | If you are using L<SQL::Translator> to create SQL for you, you can use these |
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419 | attributes to explicitly set the desired C<ON DELETE> or C<ON UPDATE> constraint |
420 | type. If not supplied the SQLT parser will attempt to infer the constraint type by |
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421 | interrogating the attributes of the B<opposite> relationship. For any 'multi' |
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422 | relationship with C<< cascade_delete => 1 >>, the corresponding belongs_to |
423 | relationship will be created with an C<ON DELETE CASCADE> constraint. For any |
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424 | relationship bearing C<< cascade_copy => 1 >> the resulting belongs_to constraint |
425 | will be C<ON UPDATE CASCADE>. If you wish to disable this autodetection, and just |
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426 | use the RDBMS' default constraint type, pass C<< on_delete => undef >> or |
e377d723 |
427 | C<< on_delete => '' >>, and the same for C<on_update> respectively. |
428 | |
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429 | =item is_deferrable |
430 | |
431 | Tells L<SQL::Translator> that the foreign key constraint it creates should be |
432 | deferrable. In other words, the user may request that the constraint be ignored |
433 | until the end of the transaction. Currently, only the PostgreSQL producer |
434 | actually supports this. |
435 | |
2581038c |
436 | =item add_fk_index |
437 | |
438 | Tells L<SQL::Translator> to add an index for this constraint. Can also be |
439 | specified globally in the args to L<DBIx::Class::Schema/deploy> or |
440 | L<DBIx::Class::Schema/create_ddl_dir>. Default is on, set to 0 to disable. |
441 | |
8091aa91 |
442 | =back |
443 | |
87c4e602 |
444 | =head2 register_relationship |
445 | |
27f01d1f |
446 | =over 4 |
447 | |
dad42de6 |
448 | =item Arguments: $rel_name, $rel_info |
27f01d1f |
449 | |
450 | =back |
71e65b39 |
451 | |
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452 | Registers a relationship on the class. This is called internally by |
71f9df37 |
453 | DBIx::Class::ResultSourceProxy to set up Accessors and Proxies. |
71e65b39 |
454 | |
55e2d745 |
455 | =cut |
456 | |
71e65b39 |
457 | sub register_relationship { } |
458 | |
27f01d1f |
459 | =head2 related_resultset |
460 | |
461 | =over 4 |
462 | |
dad42de6 |
463 | =item Arguments: $rel_name |
27f01d1f |
464 | |
dad42de6 |
465 | =item Return Value: L<$related_resultset|DBIx::Class::ResultSet> |
27f01d1f |
466 | |
467 | =back |
30236e47 |
468 | |
27f01d1f |
469 | $rs = $cd->related_resultset('artist'); |
30236e47 |
470 | |
27f01d1f |
471 | Returns a L<DBIx::Class::ResultSet> for the relationship named |
dad42de6 |
472 | $rel_name. |
30236e47 |
473 | |
93711422 |
474 | =head2 $relationship_accessor |
475 | |
476 | =over 4 |
477 | |
dad42de6 |
478 | =item Arguments: none |
93711422 |
479 | |
dad42de6 |
480 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | L<$related_resultset|DBIx::Class::ResultSet> | undef |
93711422 |
481 | |
482 | =back |
483 | |
484 | # These pairs do the same thing |
47d7b769 |
485 | $result = $cd->related_resultset('artist')->single; # has_one relationship |
486 | $result = $cd->artist; |
93711422 |
487 | $rs = $cd->related_resultset('tracks'); # has_many relationship |
488 | $rs = $cd->tracks; |
489 | |
8ed69929 |
490 | This is the recommended way to traverse through relationships, based |
93711422 |
491 | on the L</accessor> name given in the relationship definition. |
492 | |
dad42de6 |
493 | This will return either a L<Result|DBIx::Class::Manual::ResultClass> or a |
93711422 |
494 | L<ResultSet|DBIx::Class::ResultSet>, depending on if the relationship is |
495 | C<single> (returns only one row) or C<multi> (returns many rows). The |
496 | method may also return C<undef> if the relationship doesn't exist for |
497 | this instance (like in the case of C<might_have> relationships). |
498 | |
30236e47 |
499 | =cut |
500 | |
501 | sub related_resultset { |
938b7adc |
502 | $_[0]->throw_exception( |
503 | '$result->related_resultset() no longer accepts extra search arguments, ' |
504 | . 'you need to switch to ...->related_resultset($relname)->search_rs(...) ' |
505 | . 'instead (it was never documented and more importantly could never work ' |
506 | . 'reliably due to the heavy caching involved)' |
507 | ) if @_ > 2; |
72c2540d |
508 | |
938b7adc |
509 | $_[0]->throw_exception("Can't call *_related as class methods") |
510 | unless ref $_[0]; |
72c2540d |
511 | |
938b7adc |
512 | return $_[0]->{related_resultsets}{$_[1]} |
513 | if defined $_[0]->{related_resultsets}{$_[1]}; |
d4daee7b |
514 | |
938b7adc |
515 | my ($self, $rel) = @_; |
3d0733aa |
516 | |
517 | return $self->{related_resultsets}{$rel} = do { |
3b4c4d72 |
518 | |
4006691d |
519 | my $rsrc = $self->result_source; |
520 | |
521 | my $rel_info = $rsrc->relationship_info($rel) |
3b4c4d72 |
522 | or $self->throw_exception( "No such relationship '$rel'" ); |
523 | |
b70a4bb5 |
524 | my $cond_res = $rsrc->_resolve_relationship_condition( |
525 | rel_name => $rel, |
526 | self_result_object => $self, |
527 | |
528 | # this may look weird, but remember that we are making a resultset |
529 | # out of an existing object, with the new source being at the head |
530 | # of the FROM chain. Having a 'me' alias is nothing but expected there |
531 | foreign_alias => 'me', |
532 | |
533 | self_alias => "!!!\xFF()!!!_SHOULD_NEVER_BE_SEEN_IN_USE_!!!()\xFF!!!", |
534 | |
535 | # not strictly necessary, but shouldn't hurt either |
536 | require_join_free_condition => !!(ref $rel_info->{cond} ne 'CODE'), |
537 | ); |
d419ded6 |
538 | |
aa56106b |
539 | # keep in mind that the following if() block is part of a do{} - no return()s!!! |
b70a4bb5 |
540 | if ( |
541 | ! $cond_res->{join_free_condition} |
542 | and |
543 | ref $rel_info->{cond} eq 'CODE' |
544 | ) { |
aa56106b |
545 | |
546 | # A WHOREIFFIC hack to reinvoke the entire condition resolution |
547 | # with the correct alias. Another way of doing this involves a |
548 | # lot of state passing around, and the @_ positions are already |
549 | # mapped out, making this crap a less icky option. |
550 | # |
551 | # The point of this exercise is to retain the spirit of the original |
552 | # $obj->search_related($rel) where the resulting rset will have the |
553 | # root alias as 'me', instead of $rel (as opposed to invoking |
554 | # $rs->search_related) |
555 | |
777738d0 |
556 | # make the fake 'me' rel |
557 | local $rsrc->{_relationships}{me} = { |
558 | %{ $rsrc->{_relationships}{$rel} }, |
559 | _original_name => $rel, |
560 | }; |
561 | |
72c2540d |
562 | my $obj_table_alias = lc($rsrc->source_name) . '__row'; |
93508f48 |
563 | $obj_table_alias =~ s/\W+/_/g; |
aa56106b |
564 | |
72c2540d |
565 | $rsrc->resultset->search( |
aa56106b |
566 | $self->ident_condition($obj_table_alias), |
567 | { alias => $obj_table_alias }, |
938b7adc |
568 | )->search_related('me', undef, $rel_info->{attrs}) |
68f3b0dd |
569 | } |
aa56106b |
570 | else { |
938b7adc |
571 | |
aa56106b |
572 | # FIXME - this conditional doesn't seem correct - got to figure out |
573 | # at some point what it does. Also the entire UNRESOLVABLE_CONDITION |
574 | # business seems shady - we could simply not query *at all* |
b70a4bb5 |
575 | my $attrs; |
576 | if ( $cond_res->{join_free_condition} eq UNRESOLVABLE_CONDITION ) { |
577 | $attrs = { %{$rel_info->{attrs}} }; |
72c2540d |
578 | my $reverse = $rsrc->reverse_relationship_info($rel); |
aa56106b |
579 | foreach my $rev_rel (keys %$reverse) { |
580 | if ($reverse->{$rev_rel}{attrs}{accessor} && $reverse->{$rev_rel}{attrs}{accessor} eq 'multi') { |
0a03206a |
581 | weaken($attrs->{related_objects}{$rev_rel}[0] = $self); |
aa56106b |
582 | } else { |
0a03206a |
583 | weaken($attrs->{related_objects}{$rev_rel} = $self); |
aa56106b |
584 | } |
585 | } |
9aae3566 |
586 | } |
a126983e |
587 | |
b70a4bb5 |
588 | $rsrc->related_source($rel)->resultset->search( |
589 | $cond_res->{join_free_condition}, |
590 | $attrs || $rel_info->{attrs}, |
591 | ); |
7689b9e5 |
592 | } |
30236e47 |
593 | }; |
594 | } |
595 | |
8091aa91 |
596 | =head2 search_related |
503536d5 |
597 | |
dad42de6 |
598 | =over 4 |
599 | |
600 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
601 | |
602 | =item Return Value: L<$resultset|DBIx::Class::ResultSet> (scalar context) | L<@result_objs|DBIx::Class::Manual::ResultClass> (list context) |
603 | |
604 | =back |
30236e47 |
605 | |
606 | Run a search on a related resultset. The search will be restricted to the |
dad42de6 |
607 | results represented by the L<DBIx::Class::ResultSet> it was called |
608 | upon. |
609 | |
610 | See L<DBIx::Class::ResultSet/search_related> for more information. |
503536d5 |
611 | |
612 | =cut |
613 | |
55e2d745 |
614 | sub search_related { |
ff7bb7a1 |
615 | return shift->related_resultset(shift)->search(@_); |
b52e9bf8 |
616 | } |
617 | |
5b89a768 |
618 | =head2 search_related_rs |
619 | |
fd323bf1 |
620 | This method works exactly the same as search_related, except that |
48580715 |
621 | it guarantees a resultset, even in list context. |
5b89a768 |
622 | |
623 | =cut |
624 | |
625 | sub search_related_rs { |
626 | return shift->related_resultset(shift)->search_rs(@_); |
627 | } |
628 | |
b52e9bf8 |
629 | =head2 count_related |
630 | |
dad42de6 |
631 | =over 4 |
632 | |
633 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
634 | |
635 | =item Return Value: $count |
b52e9bf8 |
636 | |
dad42de6 |
637 | =back |
638 | |
639 | Returns the count of all the rows in the related resultset, restricted by the |
640 | current result or where conditions. |
30236e47 |
641 | |
b52e9bf8 |
642 | =cut |
643 | |
644 | sub count_related { |
4b8a53ea |
645 | shift->search_related(@_)->count; |
55e2d745 |
646 | } |
647 | |
30236e47 |
648 | =head2 new_related |
649 | |
dad42de6 |
650 | =over 4 |
651 | |
652 | =item Arguments: $rel_name, \%col_data |
653 | |
654 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
30236e47 |
655 | |
dad42de6 |
656 | =back |
657 | |
658 | Create a new result object of the related foreign class. It will magically set |
659 | any foreign key columns of the new object to the related primary key columns |
660 | of the source object for you. The newly created result will not be saved into |
661 | your storage until you call L<DBIx::Class::Row/insert> on it. |
30236e47 |
662 | |
663 | =cut |
664 | |
665 | sub new_related { |
83a6b244 |
666 | my ($self, $rel, $data) = @_; |
667 | |
668 | return $self->search_related($rel)->new_result( $self->result_source->_resolve_relationship_condition ( |
669 | infer_values_based_on => $data, |
670 | rel_name => $rel, |
98def3ef |
671 | self_result_object => $self, |
83a6b244 |
672 | foreign_alias => $rel, |
673 | self_alias => 'me', |
674 | )->{inferred_values} ); |
30236e47 |
675 | } |
676 | |
8091aa91 |
677 | =head2 create_related |
503536d5 |
678 | |
dad42de6 |
679 | =over 4 |
30236e47 |
680 | |
dad42de6 |
681 | =item Arguments: $rel_name, \%col_data |
682 | |
683 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
684 | |
685 | =back |
686 | |
687 | my $result = $obj->create_related($rel_name, \%col_data); |
688 | |
689 | Creates a new result object, similarly to new_related, and also inserts the |
690 | result's data into your storage medium. See the distinction between C<create> |
691 | and C<new> in L<DBIx::Class::ResultSet> for details. |
503536d5 |
692 | |
693 | =cut |
694 | |
55e2d745 |
695 | sub create_related { |
3842b955 |
696 | my $self = shift; |
fea3d045 |
697 | my $rel = shift; |
78b948c3 |
698 | my $obj = $self->new_related($rel, @_)->insert; |
64acc2bc |
699 | delete $self->{related_resultsets}->{$rel}; |
700 | return $obj; |
55e2d745 |
701 | } |
702 | |
8091aa91 |
703 | =head2 find_related |
503536d5 |
704 | |
dad42de6 |
705 | =over 4 |
706 | |
707 | =item Arguments: $rel_name, \%col_data | @pk_values, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
708 | |
709 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> | undef |
710 | |
711 | =back |
712 | |
713 | my $result = $obj->find_related($rel_name, \%col_data); |
30236e47 |
714 | |
715 | Attempt to find a related object using its primary key or unique constraints. |
27f01d1f |
716 | See L<DBIx::Class::ResultSet/find> for details. |
503536d5 |
717 | |
718 | =cut |
719 | |
1a14aa3f |
720 | sub find_related { |
4b8a53ea |
721 | #my ($self, $rel, @args) = @_; |
722 | return shift->search_related(shift)->find(@_); |
1a14aa3f |
723 | } |
724 | |
b3e1f1f5 |
725 | =head2 find_or_new_related |
726 | |
dad42de6 |
727 | =over 4 |
b3e1f1f5 |
728 | |
dad42de6 |
729 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
730 | |
731 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
732 | |
733 | =back |
734 | |
735 | Find a result object of a related class. See L<DBIx::Class::ResultSet/find_or_new> |
736 | for details. |
b3e1f1f5 |
737 | |
738 | =cut |
739 | |
740 | sub find_or_new_related { |
741 | my $self = shift; |
e60dc79f |
742 | my $obj = $self->find_related(@_); |
743 | return defined $obj ? $obj : $self->new_related(@_); |
b3e1f1f5 |
744 | } |
745 | |
8091aa91 |
746 | =head2 find_or_create_related |
503536d5 |
747 | |
dad42de6 |
748 | =over 4 |
749 | |
750 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
751 | |
752 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
753 | |
754 | =back |
30236e47 |
755 | |
dad42de6 |
756 | Find or create a result object of a related class. See |
b3e1f1f5 |
757 | L<DBIx::Class::ResultSet/find_or_create> for details. |
503536d5 |
758 | |
759 | =cut |
760 | |
55e2d745 |
761 | sub find_or_create_related { |
762 | my $self = shift; |
9c2c91ea |
763 | my $obj = $self->find_related(@_); |
764 | return (defined($obj) ? $obj : $self->create_related(@_)); |
55e2d745 |
765 | } |
766 | |
045120e6 |
767 | =head2 update_or_create_related |
768 | |
dad42de6 |
769 | =over 4 |
770 | |
771 | =item Arguments: $rel_name, \%col_data, { key => $unique_constraint, L<%attrs|DBIx::Class::ResultSet/ATTRIBUTES> }? |
772 | |
773 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
774 | |
775 | =back |
045120e6 |
776 | |
dad42de6 |
777 | Update or create a result object of a related class. See |
f7e1846f |
778 | L<DBIx::Class::ResultSet/update_or_create> for details. |
045120e6 |
779 | |
780 | =cut |
781 | |
782 | sub update_or_create_related { |
4b8a53ea |
783 | #my ($self, $rel, @args) = @_; |
784 | shift->related_resultset(shift)->update_or_create(@_); |
045120e6 |
785 | } |
786 | |
8091aa91 |
787 | =head2 set_from_related |
503536d5 |
788 | |
dad42de6 |
789 | =over 4 |
790 | |
791 | =item Arguments: $rel_name, L<$result|DBIx::Class::Manual::ResultClass> |
792 | |
793 | =item Return Value: not defined |
794 | |
795 | =back |
796 | |
30236e47 |
797 | $book->set_from_related('author', $author_obj); |
ac8e89d7 |
798 | $book->author($author_obj); ## same thing |
30236e47 |
799 | |
800 | Set column values on the current object, using related values from the given |
801 | related object. This is used to associate previously separate objects, for |
802 | example, to set the correct author for a book, find the Author object, then |
803 | call set_from_related on the book. |
804 | |
ac8e89d7 |
805 | This is called internally when you pass existing objects as values to |
48580715 |
806 | L<DBIx::Class::ResultSet/create>, or pass an object to a belongs_to accessor. |
ac8e89d7 |
807 | |
5529838f |
808 | The columns are only set in the local copy of the object, call |
809 | L<update|DBIx::Class::Row/update> to update them in the storage. |
503536d5 |
810 | |
811 | =cut |
812 | |
55e2d745 |
813 | sub set_from_related { |
814 | my ($self, $rel, $f_obj) = @_; |
aa56106b |
815 | |
83a6b244 |
816 | $self->set_columns( $self->result_source->_resolve_relationship_condition ( |
817 | infer_values_based_on => {}, |
818 | rel_name => $rel, |
e884e5d9 |
819 | foreign_values => $f_obj, |
83a6b244 |
820 | foreign_alias => $rel, |
821 | self_alias => 'me', |
822 | )->{inferred_values} ); |
a126983e |
823 | |
55e2d745 |
824 | return 1; |
825 | } |
826 | |
8091aa91 |
827 | =head2 update_from_related |
503536d5 |
828 | |
dad42de6 |
829 | =over 4 |
830 | |
831 | =item Arguments: $rel_name, L<$result|DBIx::Class::Manual::ResultClass> |
832 | |
833 | =item Return Value: not defined |
834 | |
835 | =back |
836 | |
30236e47 |
837 | $book->update_from_related('author', $author_obj); |
838 | |
27f01d1f |
839 | The same as L</"set_from_related">, but the changes are immediately updated |
840 | in storage. |
503536d5 |
841 | |
842 | =cut |
843 | |
55e2d745 |
844 | sub update_from_related { |
845 | my $self = shift; |
846 | $self->set_from_related(@_); |
847 | $self->update; |
848 | } |
849 | |
8091aa91 |
850 | =head2 delete_related |
503536d5 |
851 | |
dad42de6 |
852 | =over 4 |
30236e47 |
853 | |
dad42de6 |
854 | =item Arguments: $rel_name, $cond?, L<\%attrs?|DBIx::Class::ResultSet/ATTRIBUTES> |
855 | |
69bc5f2b |
856 | =item Return Value: $underlying_storage_rv |
dad42de6 |
857 | |
858 | =back |
859 | |
860 | Delete any related row, subject to the given conditions. Internally, this |
861 | calls: |
862 | |
863 | $self->search_related(@_)->delete |
864 | |
865 | And returns the result of that. |
503536d5 |
866 | |
867 | =cut |
868 | |
55e2d745 |
869 | sub delete_related { |
870 | my $self = shift; |
64acc2bc |
871 | my $obj = $self->search_related(@_)->delete; |
872 | delete $self->{related_resultsets}->{$_[0]}; |
873 | return $obj; |
55e2d745 |
874 | } |
875 | |
ec353f53 |
876 | =head2 add_to_$rel |
877 | |
dad42de6 |
878 | B<Currently only available for C<has_many>, C<many_to_many> and 'multi' type |
ec353f53 |
879 | relationships.> |
880 | |
dad42de6 |
881 | =head3 has_many / multi |
882 | |
ec353f53 |
883 | =over 4 |
884 | |
dad42de6 |
885 | =item Arguments: \%col_data |
886 | |
887 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
888 | |
889 | =back |
890 | |
891 | Creates/inserts a new result object. Internally, this calls: |
892 | |
893 | $self->create_related($rel, @_) |
894 | |
895 | And returns the result of that. |
896 | |
897 | =head3 many_to_many |
898 | |
899 | =over 4 |
900 | |
901 | =item Arguments: (\%col_data | L<$result|DBIx::Class::Manual::ResultClass>), \%link_col_data? |
902 | |
903 | =item Return Value: L<$result|DBIx::Class::Manual::ResultClass> |
ec353f53 |
904 | |
905 | =back |
906 | |
907 | my $role = $schema->resultset('Role')->find(1); |
908 | $actor->add_to_roles($role); |
dad42de6 |
909 | # creates a My::DBIC::Schema::ActorRoles linking table result object |
ec353f53 |
910 | |
911 | $actor->add_to_roles({ name => 'lead' }, { salary => 15_000_000 }); |
dad42de6 |
912 | # creates a new My::DBIC::Schema::Role result object and the linking table |
ec353f53 |
913 | # object with an extra column in the link |
914 | |
dad42de6 |
915 | Adds a linking table object. If the first argument is a hash reference, the |
916 | related object is created first with the column values in the hash. If an object |
917 | reference is given, just the linking table object is created. In either case, |
918 | any additional column values for the linking table object can be specified in |
919 | C<\%link_col_data>. |
920 | |
921 | See L<DBIx::Class::Relationship/many_to_many> for additional details. |
ec353f53 |
922 | |
923 | =head2 set_$rel |
924 | |
dad42de6 |
925 | B<Currently only available for C<many_to_many> relationships.> |
ec353f53 |
926 | |
927 | =over 4 |
928 | |
dad42de6 |
929 | =item Arguments: (\@hashrefs_of_col_data | L<\@result_objs|DBIx::Class::Manual::ResultClass>), $link_vals? |
930 | |
931 | =item Return Value: not defined |
ec353f53 |
932 | |
933 | =back |
934 | |
935 | my $actor = $schema->resultset('Actor')->find(1); |
fd323bf1 |
936 | my @roles = $schema->resultset('Role')->search({ role => |
debccec3 |
937 | { '-in' => ['Fred', 'Barney'] } } ); |
ec353f53 |
938 | |
4d3a827d |
939 | $actor->set_roles(\@roles); |
940 | # Replaces all of $actor's previous roles with the two named |
ec353f53 |
941 | |
ac36a402 |
942 | $actor->set_roles(\@roles, { salary => 15_000_000 }); |
943 | # Sets a column in the link table for all roles |
944 | |
945 | |
4d3a827d |
946 | Replace all the related objects with the given reference to a list of |
947 | objects. This does a C<delete> B<on the link table resultset> to remove the |
948 | association between the current object and all related objects, then calls |
949 | C<add_to_$rel> repeatedly to link all the new objects. |
bba68c67 |
950 | |
951 | Note that this means that this method will B<not> delete any objects in the |
952 | table on the right side of the relation, merely that it will delete the link |
953 | between them. |
ec353f53 |
954 | |
4d3a827d |
955 | Due to a mistake in the original implementation of this method, it will also |
956 | accept a list of objects or hash references. This is B<deprecated> and will be |
957 | removed in a future version. |
958 | |
ec353f53 |
959 | =head2 remove_from_$rel |
960 | |
dad42de6 |
961 | B<Currently only available for C<many_to_many> relationships.> |
ec353f53 |
962 | |
963 | =over 4 |
964 | |
dad42de6 |
965 | =item Arguments: L<$result|DBIx::Class::Manual::ResultClass> |
966 | |
967 | =item Return Value: not defined |
ec353f53 |
968 | |
969 | =back |
970 | |
971 | my $role = $schema->resultset('Role')->find(1); |
972 | $actor->remove_from_roles($role); |
dad42de6 |
973 | # removes $role's My::DBIC::Schema::ActorRoles linking table result object |
ec353f53 |
974 | |
975 | Removes the link between the current object and the related object. Note that |
976 | the related object itself won't be deleted unless you call ->delete() on |
977 | it. This method just removes the link between the two objects. |
978 | |
a2bd3796 |
979 | =head1 FURTHER QUESTIONS? |
55e2d745 |
980 | |
a2bd3796 |
981 | Check the list of L<additional DBIC resources|DBIx::Class/GETTING HELP/SUPPORT>. |
55e2d745 |
982 | |
a2bd3796 |
983 | =head1 COPYRIGHT AND LICENSE |
55e2d745 |
984 | |
a2bd3796 |
985 | This module is free software L<copyright|DBIx::Class/COPYRIGHT AND LICENSE> |
986 | by the L<DBIx::Class (DBIC) authors|DBIx::Class/AUTHORS>. You can |
987 | redistribute it and/or modify it under the same terms as the |
988 | L<DBIx::Class library|DBIx::Class/COPYRIGHT AND LICENSE>. |
55e2d745 |
989 | |
990 | =cut |
991 | |
4d87db01 |
992 | 1; |