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 | |
12 | DBIx::Class::Relationship - Inter-table relationships |
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 | |
26 | =cut |
27 | |
28 | sub add_relationship { |
29 | my ($class, $rel, $f_class, $cond, $attrs) = @_; |
30 | die "Can't create relationship without join condition" unless $cond; |
31 | $attrs ||= {}; |
32 | eval "use $f_class;"; |
33 | my %rels = %{ $class->_relationships }; |
34 | $rels{$rel} = { class => $f_class, |
35 | cond => $cond, |
36 | attrs => $attrs }; |
37 | $class->_relationships(\%rels); |
38 | #warn %{$f_class->_columns}; |
39 | |
40 | return unless eval { %{$f_class->_columns}; }; # Foreign class not loaded |
41 | my %join = (%$attrs, _action => 'join', |
42 | _aliases => { 'self' => 'me', 'foreign' => $rel }, |
43 | _classes => { 'me' => $class, $rel => $f_class }); |
44 | eval { $class->_cond_resolve($cond, \%join) }; |
45 | |
46 | if ($@) { # If the resolve failed, back out and re-throw the error |
47 | delete $rels{$rel}; # |
48 | $class->_relationships(\%rels); |
49 | $class->throw("Error creating relationship $rel: $@"); |
50 | } |
51 | 1; |
52 | } |
53 | |
54 | sub _cond_key { |
55 | my ($self, $attrs, $key) = @_; |
56 | my $action = $attrs->{_action} || ''; |
57 | if ($action eq 'convert') { |
58 | unless ($key =~ s/^foreign\.//) { |
59 | $self->throw("Unable to convert relationship to WHERE clause: invalid key ${key}"); |
60 | } |
61 | return $key; |
62 | } elsif ($action eq 'join') { |
63 | my ($type, $field) = split(/\./, $key); |
64 | if (my $alias = $attrs->{_aliases}{$type}) { |
65 | my $class = $attrs->{_classes}{$alias}; |
66 | $self->throw("Unknown column $field on $class as $alias") |
67 | unless exists $class->_columns->{$field}; |
68 | return join('.', $alias, $field); |
69 | } else { |
70 | $self->throw( "Unable to resolve type ${type}: only have aliases for ". |
71 | join(', ', keys %{$attrs->{_aliases} || {}}) ); |
72 | } |
73 | } |
74 | return $self->NEXT::ACTUAL::_cond_key($attrs, $key); |
75 | } |
76 | |
77 | sub _cond_value { |
78 | my ($self, $attrs, $key, $value) = @_; |
79 | my $action = $attrs->{_action} || ''; |
80 | if ($action eq 'convert') { |
81 | unless ($value =~ s/^self\.//) { |
82 | $self->throw( "Unable to convert relationship to WHERE clause: invalid value ${value}" ); |
83 | } |
84 | unless ($self->_columns->{$value}) { |
85 | $self->throw( "Unable to convert relationship to WHERE clause: no such accessor ${value}" ); |
86 | } |
87 | push(@{$attrs->{bind}}, $self->get_column($value)); |
88 | return '?'; |
89 | } elsif ($action eq 'join') { |
90 | my ($type, $field) = split(/\./, $value); |
91 | if (my $alias = $attrs->{_aliases}{$type}) { |
92 | my $class = $attrs->{_classes}{$alias}; |
93 | $self->throw("Unknown column $field on $class as $alias") |
94 | unless exists $class->_columns->{$field}; |
95 | return join('.', $alias, $field); |
96 | } else { |
97 | $self->throw( "Unable to resolve type ${type}: only have aliases for ". |
98 | join(', ', keys %{$attrs->{_aliases} || {}}) ); |
99 | } |
100 | } |
101 | |
102 | return $self->NEXT::ACTUAL::_cond_value($attrs, $key, $value) |
103 | } |
104 | |
105 | sub search_related { |
106 | my $self = shift; |
107 | return $self->_query_related('search', @_); |
108 | } |
109 | |
110 | sub count_related { |
111 | my $self = shift; |
112 | return $self->_query_related('count', @_); |
113 | } |
114 | |
115 | sub _query_related { |
116 | my $self = shift; |
117 | my $meth = shift; |
118 | my $rel = shift; |
119 | my $attrs = { }; |
120 | if (@_ > 1 && ref $_[$#_] eq 'HASH') { |
121 | $attrs = { %{ pop(@_) } }; |
122 | } |
123 | my $rel_obj = $self->_relationships->{$rel}; |
124 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
125 | $attrs = { %{$rel_obj->{attrs} || {}}, %{$attrs || {}} }; |
126 | |
127 | $self->throw( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1)); |
128 | my $query = ((@_ > 1) ? {@_} : shift); |
129 | |
130 | $attrs->{_action} = 'convert'; # shouldn't we resolve the cond to something |
131 | # to merge into the AST really? |
132 | my ($cond) = $self->_cond_resolve($rel_obj->{cond}, $attrs); |
133 | $query = ($query ? { '-and' => [ \$cond, $query ] } : \$cond); |
134 | #use Data::Dumper; warn Dumper($query); |
135 | #warn $rel_obj->{class}." $meth $cond ".join(', ', @{$attrs->{bind}}); |
136 | delete $attrs->{_action}; |
137 | return $self->resolve_class($rel_obj->{class} |
138 | )->$meth($query, $attrs); |
139 | } |
140 | |
141 | sub create_related { |
142 | my $class = shift; |
143 | return $class->new_related(@_)->insert; |
144 | } |
145 | |
146 | sub new_related { |
147 | my ($self, $rel, $values, $attrs) = @_; |
148 | $self->throw( "Can't call new_related as class method" ) |
149 | unless ref $self; |
150 | $self->throw( "new_related needs a hash" ) |
151 | unless (ref $values eq 'HASH'); |
152 | my $rel_obj = $self->_relationships->{$rel}; |
153 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
154 | $self->throw( "Can't abstract implicit create for ${rel}, condition not a hash" ) |
155 | unless ref $rel_obj->{cond} eq 'HASH'; |
156 | $attrs = { %{$rel_obj->{attrs}}, %{$attrs || {}}, _action => 'convert' }; |
157 | my %fields = %$values; |
158 | while (my ($k, $v) = each %{$rel_obj->{cond}}) { |
159 | $self->_cond_value($attrs, $k => $v); |
160 | $fields{$self->_cond_key($attrs, $k)} = (@{delete $attrs->{bind}})[0]; |
161 | } |
162 | return $self->resolve_class($rel_obj->{class})->new(\%fields); |
163 | } |
164 | |
165 | sub find_or_create_related { |
166 | my $self = shift; |
167 | return ($self->search_related(@_))[0] || $self->create_related(@_); |
168 | } |
169 | |
170 | sub set_from_related { |
171 | my ($self, $rel, $f_obj) = @_; |
172 | my $rel_obj = $self->_relationships->{$rel}; |
173 | $self->throw( "No such relationship ${rel}" ) unless $rel_obj; |
174 | my $cond = $rel_obj->{cond}; |
175 | $self->throw( "set_from_related can only handle a hash condition; the " |
176 | ."condition for $rel is of type ".(ref $cond ? ref $cond : 'plain scalar')) |
177 | unless ref $cond eq 'HASH'; |
178 | my $f_class = $self->resolve_class($rel_obj->{class}); |
179 | $self->throw( "Object $f_obj isn't a ".$f_class ) |
180 | unless $f_obj->isa($f_class); |
181 | foreach my $key (keys %$cond) { |
182 | next if ref $cond->{$key}; # Skip literals and complex conditions |
183 | $self->throw("set_from_related can't handle $key as key") |
184 | unless $key =~ m/^foreign\.([^\.]+)$/; |
185 | my $val = $f_obj->get_column($1); |
186 | $self->throw("set_from_related can't handle ".$cond->{$key}." as value") |
187 | unless $cond->{$key} =~ m/^self\.([^\.]+)$/; |
188 | $self->set_column($1 => $val); |
189 | } |
190 | return 1; |
191 | } |
192 | |
193 | sub update_from_related { |
194 | my $self = shift; |
195 | $self->set_from_related(@_); |
196 | $self->update; |
197 | } |
198 | |
199 | sub delete_related { |
200 | my $self = shift; |
201 | return $self->search_related(@_)->delete; |
202 | } |
203 | |
204 | 1; |
205 | |
206 | =back |
207 | |
208 | =head1 AUTHORS |
209 | |
210 | Matt S. Trout <perl-stuff@trout.me.uk> |
211 | |
212 | =head1 LICENSE |
213 | |
214 | You may distribute this code under the same terms as Perl itself. |
215 | |
216 | =cut |
217 | |