Commit | Line | Data |
55e2d745 |
1 | package DBIx::Class::Relationship::Base; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | |
6 | use base qw/Class::Data::Inheritable/; |
7 | |
8 | __PACKAGE__->mk_classdata('_relationships', { } ); |
9 | |
10 | =head1 NAME |
11 | |
8918977e |
12 | DBIx::Class::Relationship::Base - Inter-table relationships |
55e2d745 |
13 | |
14 | =head1 SYNOPSIS |
15 | |
16 | =head1 DESCRIPTION |
17 | |
18 | This class handles relationships between the tables in your database |
19 | model. It allows your to set up relationships, and to perform joins |
20 | on searches. |
21 | |
22 | =head1 METHODS |
23 | |
24 | =over 4 |
25 | |
503536d5 |
26 | =item add_relationship |
27 | |
28 | __PACKAGE__->add_relationship('relname', 'Foreign::Class', $cond, $attrs); |
29 | |
30 | The condition needs to be an SQL::Abstract-style representation of the |
31 | join between the tables - for example if you're creating a rel from Foo to Bar |
32 | |
33 | { 'foreign.foo_id' => 'self.id' } |
34 | |
35 | will result in a JOIN clause like |
36 | |
37 | foo me JOIN bar bar ON bar.foo_id = me.id |
38 | |
55e2d745 |
39 | =cut |
40 | |
41 | sub add_relationship { |
42 | my ($class, $rel, $f_class, $cond, $attrs) = @_; |
43 | die "Can't create relationship without join condition" unless $cond; |
44 | $attrs ||= {}; |
fcafefc8 |
45 | eval "require $f_class;"; |
55e2d745 |
46 | my %rels = %{ $class->_relationships }; |
47 | $rels{$rel} = { class => $f_class, |
48 | cond => $cond, |
49 | attrs => $attrs }; |
50 | $class->_relationships(\%rels); |
55e2d745 |
51 | |
103647d5 |
52 | return unless eval { $f_class->can('columns'); }; # Foreign class not loaded |
fef5d100 |
53 | eval { $class->_resolve_join($rel, 'me') }; |
55e2d745 |
54 | |
55 | if ($@) { # If the resolve failed, back out and re-throw the error |
56 | delete $rels{$rel}; # |
57 | $class->_relationships(\%rels); |
58 | $class->throw("Error creating relationship $rel: $@"); |
59 | } |
60 | 1; |
61 | } |
62 | |
fef5d100 |
63 | sub _resolve_join { |
64 | my ($class, $join, $alias) = @_; |
65 | if (ref $join eq 'ARRAY') { |
66 | return map { $class->_resolve_join($_, $alias) } @$join; |
67 | } elsif (ref $join eq 'HASH') { |
68 | return map { $class->_resolve_join($_, $alias), |
69 | $class->_relationships->{$_}{class}->_resolve_join($join->{$_}, $_) } |
70 | keys %$join; |
71 | } elsif (ref $join) { |
72 | $class->throw("No idea how to resolve join reftype ".ref $join); |
73 | } else { |
74 | my $rel_obj = $class->_relationships->{$join}; |
75 | $class->throw("No such relationship ${join}") unless $rel_obj; |
76 | my $j_class = $rel_obj->{class}; |
77 | my %join = (_action => 'join', |
78 | _aliases => { 'self' => $alias, 'foreign' => $join }, |
79 | _classes => { $alias => $class, $join => $j_class }); |
80 | my $j_cond = $j_class->resolve_condition($rel_obj->{cond}, \%join); |
81 | return [ { $join => $j_class->_table_name, |
82 | -join_type => $rel_obj->{attrs}{join_type} || '' }, $j_cond ]; |
83 | } |
84 | } |
85 | |
438adc0e |
86 | sub resolve_condition { |
87 | my ($self, $cond, $attrs) = @_; |
88 | if (ref $cond eq 'HASH') { |
89 | my %ret; |
90 | foreach my $key (keys %$cond) { |
91 | my $val = $cond->{$key}; |
92 | if (ref $val) { |
93 | $self->throw("Can't handle this yet :("); |
94 | } else { |
95 | $ret{$self->_cond_key($attrs => $key)} |
96 | = $self->_cond_value($attrs => $key => $val); |
97 | } |
98 | } |
99 | return \%ret; |
100 | } else { |
101 | $self->throw("Can't handle this yet :("); |
102 | } |
103 | } |
104 | |
55e2d745 |
105 | sub _cond_key { |
106 | my ($self, $attrs, $key) = @_; |
107 | my $action = $attrs->{_action} || ''; |
108 | if ($action eq 'convert') { |
109 | unless ($key =~ s/^foreign\.//) { |
110 | $self->throw("Unable to convert relationship to WHERE clause: invalid key ${key}"); |
111 | } |
112 | return $key; |
113 | } elsif ($action eq 'join') { |
d3dec624 |
114 | return $key unless $key =~ /\./; |
55e2d745 |
115 | my ($type, $field) = split(/\./, $key); |
116 | if (my $alias = $attrs->{_aliases}{$type}) { |
117 | my $class = $attrs->{_classes}{$alias}; |
118 | $self->throw("Unknown column $field on $class as $alias") |
103647d5 |
119 | unless $class->has_column($field); |
55e2d745 |
120 | return join('.', $alias, $field); |
121 | } else { |
122 | $self->throw( "Unable to resolve type ${type}: only have aliases for ". |
123 | join(', ', keys %{$attrs->{_aliases} || {}}) ); |
124 | } |
125 | } |
147dd158 |
126 | return $self->next::method($attrs, $key); |
55e2d745 |
127 | } |
128 | |
129 | sub _cond_value { |
130 | my ($self, $attrs, $key, $value) = @_; |
131 | my $action = $attrs->{_action} || ''; |
132 | if ($action eq 'convert') { |
133 | unless ($value =~ s/^self\.//) { |
134 | $self->throw( "Unable to convert relationship to WHERE clause: invalid value ${value}" ); |
135 | } |
103647d5 |
136 | unless ($self->has_column($value)) { |
55e2d745 |
137 | $self->throw( "Unable to convert relationship to WHERE clause: no such accessor ${value}" ); |
138 | } |
438adc0e |
139 | return $self->get_column($value); |
55e2d745 |
140 | } elsif ($action eq 'join') { |
d3dec624 |
141 | return $key unless $key =~ /\./; |
55e2d745 |
142 | my ($type, $field) = split(/\./, $value); |
143 | if (my $alias = $attrs->{_aliases}{$type}) { |
144 | my $class = $attrs->{_classes}{$alias}; |
145 | $self->throw("Unknown column $field on $class as $alias") |
103647d5 |
146 | unless $class->has_column($field); |
fef5d100 |
147 | return join('.', $alias, $field); |
55e2d745 |
148 | } else { |
149 | $self->throw( "Unable to resolve type ${type}: only have aliases for ". |
150 | join(', ', keys %{$attrs->{_aliases} || {}}) ); |
151 | } |
152 | } |
153 | |
147dd158 |
154 | return $self->next::method($attrs, $key, $value) |
55e2d745 |
155 | } |
156 | |
503536d5 |
157 | =item search_related |
158 | |
159 | My::Table->search_related('relname', $cond, $attrs); |
160 | |
161 | =cut |
162 | |
55e2d745 |
163 | sub search_related { |
164 | my $self = shift; |
165 | return $self->_query_related('search', @_); |
166 | } |
167 | |
503536d5 |
168 | =item count_related |
169 | |
170 | My::Table->count_related('relname', $cond, $attrs); |
171 | |
172 | =cut |
173 | |
55e2d745 |
174 | sub count_related { |
175 | my $self = shift; |
176 | return $self->_query_related('count', @_); |
177 | } |
178 | |
179 | sub _query_related { |
180 | my $self = shift; |
181 | my $meth = shift; |
182 | my $rel = shift; |
183 | my $attrs = { }; |
184 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
185 | $attrs = { %{ pop(@_) } }; |
186 | } |
187 | my $rel_obj = $self->_relationships->{$rel}; |
188 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
189 | $attrs = { %{$rel_obj->{attrs} || {}}, %{$attrs || {}} }; |
190 | |
191 | $self->throw( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1)); |
192 | my $query = ((@_ > 1) ? {@_} : shift); |
193 | |
194 | $attrs->{_action} = 'convert'; # shouldn't we resolve the cond to something |
195 | # to merge into the AST really? |
438adc0e |
196 | my ($cond) = $self->resolve_condition($rel_obj->{cond}, $attrs); |
197 | $query = ($query ? { '-and' => [ $cond, $query ] } : $cond); |
55e2d745 |
198 | #use Data::Dumper; warn Dumper($query); |
438adc0e |
199 | #warn $rel_obj->{class}." $meth $cond ".join(', ', @{$attrs->{bind}||[]}); |
55e2d745 |
200 | delete $attrs->{_action}; |
201 | return $self->resolve_class($rel_obj->{class} |
202 | )->$meth($query, $attrs); |
203 | } |
204 | |
503536d5 |
205 | =item create_related |
206 | |
207 | My::Table->create_related('relname', \%col_data); |
208 | |
209 | =cut |
210 | |
55e2d745 |
211 | sub create_related { |
212 | my $class = shift; |
213 | return $class->new_related(@_)->insert; |
214 | } |
215 | |
503536d5 |
216 | =item new_related |
217 | |
218 | My::Table->new_related('relname', \%col_data); |
219 | |
220 | =cut |
221 | |
55e2d745 |
222 | sub new_related { |
223 | my ($self, $rel, $values, $attrs) = @_; |
224 | $self->throw( "Can't call new_related as class method" ) |
225 | unless ref $self; |
226 | $self->throw( "new_related needs a hash" ) |
227 | unless (ref $values eq 'HASH'); |
228 | my $rel_obj = $self->_relationships->{$rel}; |
229 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
230 | $self->throw( "Can't abstract implicit create for ${rel}, condition not a hash" ) |
231 | unless ref $rel_obj->{cond} eq 'HASH'; |
232 | $attrs = { %{$rel_obj->{attrs}}, %{$attrs || {}}, _action => 'convert' }; |
438adc0e |
233 | |
234 | my %fields = %{$self->resolve_condition($rel_obj->{cond},$attrs)}; |
235 | $fields{$_} = $values->{$_} for keys %$values; |
236 | |
55e2d745 |
237 | return $self->resolve_class($rel_obj->{class})->new(\%fields); |
238 | } |
239 | |
503536d5 |
240 | =item find_related |
241 | |
242 | My::Table->find_related('relname', @pri_vals | \%pri_vals); |
243 | |
244 | =cut |
245 | |
1a14aa3f |
246 | sub find_related { |
247 | my $self = shift; |
248 | my $rel = shift; |
249 | my $rel_obj = $self->_relationships->{$rel}; |
250 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
251 | my ($cond) = $self->resolve_condition($rel_obj->{cond}, { _action => 'convert' }); |
252 | $self->throw( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1)); |
253 | my $attrs = { }; |
254 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
255 | $attrs = { %{ pop(@_) } }; |
256 | } |
257 | my $query = ((@_ > 1) ? {@_} : shift); |
258 | $query = ($query ? { '-and' => [ $cond, $query ] } : $cond); |
259 | return $self->resolve_class($rel_obj->{class})->find($query); |
260 | } |
261 | |
503536d5 |
262 | =item find_or_create_related |
263 | |
264 | My::Table->find_or_create_related('relname', \%col_data); |
265 | |
266 | =cut |
267 | |
55e2d745 |
268 | sub find_or_create_related { |
269 | my $self = shift; |
1a14aa3f |
270 | return $self->find_related(@_) || $self->create_related(@_); |
55e2d745 |
271 | } |
272 | |
503536d5 |
273 | =item set_from_related |
274 | |
275 | My::Table->set_from_related('relname', $rel_obj); |
276 | |
277 | =cut |
278 | |
55e2d745 |
279 | sub set_from_related { |
280 | my ($self, $rel, $f_obj) = @_; |
281 | my $rel_obj = $self->_relationships->{$rel}; |
282 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
283 | my $cond = $rel_obj->{cond}; |
284 | $self->throw( "set_from_related can only handle a hash condition; the " |
285 | ."condition for $rel is of type ".(ref $cond ? ref $cond : 'plain scalar')) |
286 | unless ref $cond eq 'HASH'; |
287 | my $f_class = $self->resolve_class($rel_obj->{class}); |
288 | $self->throw( "Object $f_obj isn't a ".$f_class ) |
289 | unless $f_obj->isa($f_class); |
290 | foreach my $key (keys %$cond) { |
291 | next if ref $cond->{$key}; # Skip literals and complex conditions |
292 | $self->throw("set_from_related can't handle $key as key") |
293 | unless $key =~ m/^foreign\.([^\.]+)$/; |
294 | my $val = $f_obj->get_column($1); |
295 | $self->throw("set_from_related can't handle ".$cond->{$key}." as value") |
296 | unless $cond->{$key} =~ m/^self\.([^\.]+)$/; |
297 | $self->set_column($1 => $val); |
298 | } |
299 | return 1; |
300 | } |
301 | |
503536d5 |
302 | =item update_from_related |
303 | |
304 | My::Table->update_from_related('relname', $rel_obj); |
305 | |
306 | =cut |
307 | |
55e2d745 |
308 | sub update_from_related { |
309 | my $self = shift; |
310 | $self->set_from_related(@_); |
311 | $self->update; |
312 | } |
313 | |
503536d5 |
314 | =item delete_related |
315 | |
316 | My::Table->delete_related('relname', $cond, $attrs); |
317 | |
318 | =cut |
319 | |
55e2d745 |
320 | sub delete_related { |
321 | my $self = shift; |
322 | return $self->search_related(@_)->delete; |
323 | } |
324 | |
325 | 1; |
326 | |
327 | =back |
328 | |
329 | =head1 AUTHORS |
330 | |
daec44b8 |
331 | Matt S. Trout <mst@shadowcatsystems.co.uk> |
55e2d745 |
332 | |
333 | =head1 LICENSE |
334 | |
335 | You may distribute this code under the same terms as Perl itself. |
336 | |
337 | =cut |
338 | |