-package DBIx::Class::Relationship::BelongsTo;
+package # hide from PAUSE
+ DBIx::Class::Relationship::BelongsTo;
+
+# Documentation for these methods can be found in
+# DBIx::Class::Relationship
use strict;
use warnings;
+use Try::Tiny;
+use namespace::clean;
+
+our %_pod_inherit_config =
+ (
+ class_map => { 'DBIx::Class::Relationship::BelongsTo' => 'DBIx::Class::Relationship' }
+ );
sub belongs_to {
my ($class, $rel, $f_class, $cond, $attrs) = @_;
- eval "require $f_class";
- my %f_primaries;
- $f_primaries{$_} = 1 for eval { $f_class->primary_columns };
- my $f_loaded = !$@;
- # single key relationship
- if (not defined $cond) {
- $class->throw("Can't infer join condition for ${rel} on ${class}; unable to load ${f_class}") unless $f_loaded;
+
+ # assume a foreign key contraint unless defined otherwise
+ $attrs->{is_foreign_key_constraint} = 1
+ if not exists $attrs->{is_foreign_key_constraint};
+ $attrs->{undef_on_null_fk} = 1
+ if not exists $attrs->{undef_on_null_fk};
+
+ # no join condition or just a column name
+ if (!ref $cond) {
+ $class->ensure_class_loaded($f_class);
+ my %f_primaries = map { $_ => 1 } try { $f_class->_pri_cols }
+ catch {
+ $class->throw_exception( "Can't infer join condition for ${rel} on ${class}: $_");
+ };
+
my ($pri, $too_many) = keys %f_primaries;
- $class->throw("Can't infer join condition for ${rel} on ${class}; ${f_class} has multiple primary key") if $too_many;
- my $acc_type = ($class->has_column($rel)) ? 'filter' : 'single';
- $class->add_relationship($rel, $f_class,
- { "foreign.${pri}" => "self.${rel}" },
- { accessor => $acc_type, %{$attrs || {}} }
- );
+ $class->throw_exception(
+ "Can't infer join condition for ${rel} on ${class}; ".
+ "${f_class} has multiple primary keys"
+ ) if $too_many;
+
+ my $fk = defined $cond ? $cond : $rel;
+ $class->throw_exception(
+ "Can't infer join condition for ${rel} on ${class}; ".
+ "$fk is not a column of $class"
+ ) unless $class->has_column($fk);
+
+ $cond = { "foreign.${pri}" => "self.${fk}" };
+
}
- # multiple key relationship
- else {
- my $cond_rel;
- for (keys %$cond) {
- if (m/\./) { # Explicit join condition
- $cond_rel = $cond;
- last;
+ # explicit join condition
+ elsif (ref $cond) {
+ if (ref $cond eq 'HASH') { # ARRAY is also valid
+ my $cond_rel;
+ for (keys %$cond) {
+ if (m/\./) { # Explicit join condition
+ $cond_rel = $cond;
+ last;
+ }
+ $cond_rel->{"foreign.$_"} = "self.".$cond->{$_};
}
- $cond_rel->{"foreign.$_"} = "self.".$cond->{$_};
+ $cond = $cond_rel;
}
- $class->add_relationship($rel, $f_class,
- $cond_rel,
- { accessor => 'single', %{$attrs || {}} }
+ }
+ # dunno
+ else {
+ $class->throw_exception(
+ 'third argument for belongs_to must be undef, a column name, '.
+ 'or a join condition'
);
}
- return 1;
-}
-=head1 AUTHORS
+ my $acc_type = (
+ ref $cond eq 'HASH'
+ and
+ keys %$cond == 1
+ and
+ $class->has_column($rel)
+ ) ? 'filter' : 'single';
+
+ my $fk_columns = ($acc_type eq 'single' and ref $cond eq 'HASH')
+ ? { map { $_ =~ /^self\.(.+)/ ? ( $1 => 1 ) : () } (values %$cond ) }
+ : undef
+ ;
-Alexander Hartmaier <Alexander.Hartmaier@t-systems.at>
+ $class->add_relationship($rel, $f_class,
+ $cond,
+ {
+ accessor => $acc_type,
+ $fk_columns ? ( fk_columns => $fk_columns ) : (),
+ %{$attrs || {}}
+ }
+ );
+
+ return 1;
+}
-Matt S. Trout <mst@shadowcatsystems.co.uk>
+# Attempt to remove the POD so it (maybe) falls off the indexer
-=cut
+#=head1 AUTHORS
+#
+#Alexander Hartmaier <Alexander.Hartmaier@t-systems.at>
+#
+#Matt S. Trout <mst@shadowcatsystems.co.uk>
+#
+#=cut
1;