-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;
sub belongs_to {
my ($class, $rel, $f_class, $cond, $attrs) = @_;
- eval "require $f_class";
- # single key relationship
- if (not defined $cond) {
- my ($pri, $too_many) = keys %{ $f_class->_primaries };
- my $acc_type = ($class->_columns->{$rel}) ? 'filter' : 'single';
+ # no join condition or just a column name
+ if (!ref $cond) {
+ $class->ensure_class_loaded($f_class);
+ my %f_primaries = map { $_ => 1 } eval { $f_class->primary_columns };
+ $class->throw_exception(
+ "Can't infer join condition for ${rel} on ${class}; ".
+ "unable to load ${f_class}: $@"
+ ) if $@;
+
+ my ($pri, $too_many) = keys %f_primaries;
+ $class->throw_exception(
+ "Can't infer join condition for ${rel} on ${class}; ".
+ "${f_class} has no primary keys"
+ ) unless defined $pri;
+ $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);
+
+ my $acc_type = $class->has_column($rel) ? 'filter' : 'single';
$class->add_relationship($rel, $f_class,
- { "foreign.${pri}" => "self.${rel}" },
- { accessor => $acc_type }
+ { "foreign.${pri}" => "self.${fk}" },
+ { accessor => $acc_type, %{$attrs || {}} }
);
}
- # multiple key relationship
- else {
- my %f_primaries = %{ $f_class->_primaries };
+ # explicit join condition
+ elsif (ref $cond eq 'HASH') {
my $cond_rel;
for (keys %$cond) {
- $cond_rel->{"foreign.$_"} = "self.".$cond->{$_};
- # primary key usage checks
- if (exists $f_primaries{$_}) {
- delete $f_primaries{$_};
- }
- else
- {
- $class->throw("non primary key used in join condition: $_");
+ if (m/\./) { # Explicit join condition
+ $cond_rel = $cond;
+ last;
}
+ $cond_rel->{"foreign.$_"} = "self.".$cond->{$_};
}
- $class->throw("not all primary keys used in multi key relationship!") if keys %f_primaries;
+ my $acc_type = (keys %$cond_rel == 1 and $class->has_column($rel))
+ ? 'filter'
+ : 'single';
$class->add_relationship($rel, $f_class,
$cond_rel,
- { accessor => 'single', %{$attrs ||{}} }
+ { accessor => $acc_type, %{$attrs || {}} }
+ );
+ }
+ else {
+ $class->throw_exception(
+ 'third argument for belongs_to must be undef, a column name, '.
+ 'or a join condition'
);
}
return 1;