__PACKAGE__->mk_classdata('_relationships', { } );
+=head1 NAME
+
+DBIx::Class::Relationship - Inter-table relationships
+
+=head1 SYNOPSIS
+
+=head1 DESCRIPTION
+
+This class handles relationships between the tables in your database
+model. It allows your to set up relationships, and to perform joins
+on searches.
+
+=head1 METHODS
+
+=over 4
+
+=cut
+
sub add_relationship {
my ($class, $rel, $f_class, $cond, $attrs) = @_;
+ die "Can't create relationship without join condition" unless $cond;
+ $attrs ||= {};
+ eval "use $f_class;";
my %rels = %{ $class->_relationships };
$rels{$rel} = { class => $f_class,
cond => $cond,
attrs => $attrs };
$class->_relationships(\%rels);
+ #warn %{$f_class->_columns};
+
+ return unless eval { %{$f_class->_columns}; }; # Foreign class not loaded
+ my %join = (%$attrs, _action => 'join',
+ _aliases => { 'self' => 'me', 'foreign' => $rel },
+ _classes => { 'me' => $class, $rel => $f_class });
+ eval { $class->_cond_resolve($cond, \%join) };
+
+ if ($@) { # If the resolve failed, back out and re-throw the error
+ delete $rels{$rel}; #
+ $class->_relationships(\%rels);
+ $class->throw("Error creating relationship $rel: $@");
+ }
+ 1;
}
sub _cond_key {
my $action = $attrs->{_action} || '';
if ($action eq 'convert') {
unless ($key =~ s/^foreign\.//) {
- die "Unable to convert relationship to WHERE clause: invalid key ${key}";
+ $self->throw("Unable to convert relationship to WHERE clause: invalid key ${key}");
}
return $key;
} elsif ($action eq 'join') {
my ($type, $field) = split(/\./, $key);
- if ($attrs->{_aliases}{$type}) {
- return join('.', $attrs->{_aliases}{$type}, $field);
+ if (my $alias = $attrs->{_aliases}{$type}) {
+ my $class = $attrs->{_classes}{$alias};
+ $self->throw("Unknown column $field on $class as $alias")
+ unless exists $class->_columns->{$field};
+ return join('.', $alias, $field);
} else {
- die "Unable to resolve type ${type}: only have aliases for ".
- join(', ', keys %{$attrs->{_aliases}{$type} || {}});
+ $self->throw( "Unable to resolve type ${type}: only have aliases for ".
+ join(', ', keys %{$attrs->{_aliases} || {}}) );
}
}
return $self->NEXT::ACTUAL::_cond_key($attrs, $key);
my $action = $attrs->{_action} || '';
if ($action eq 'convert') {
unless ($value =~ s/^self\.//) {
- die "Unable to convert relationship to WHERE clause: invalid value ${value}";
+ $self->throw( "Unable to convert relationship to WHERE clause: invalid value ${value}" );
}
- unless ($self->can($value)) {
- die "Unable to convert relationship to WHERE clause: no such accessor ${value}";
+ unless ($self->_columns->{$value}) {
+ $self->throw( "Unable to convert relationship to WHERE clause: no such accessor ${value}" );
}
push(@{$attrs->{bind}}, $self->get_column($value));
return '?';
} elsif ($action eq 'join') {
my ($type, $field) = split(/\./, $value);
- if ($attrs->{_aliases}{$type}) {
- return join('.', $attrs->{_aliases}{$type}, $field);
+ if (my $alias = $attrs->{_aliases}{$type}) {
+ my $class = $attrs->{_classes}{$alias};
+ $self->throw("Unknown column $field on $class as $alias")
+ unless exists $class->_columns->{$field};
+ return join('.', $alias, $field);
} else {
- die "Unable to resolve type ${type}: only have aliases for ".
- join(', ', keys %{$attrs->{_aliases}{$type} || {}});
+ $self->throw( "Unable to resolve type ${type}: only have aliases for ".
+ join(', ', keys %{$attrs->{_aliases} || {}}) );
}
}
sub search_related {
my $self = shift;
+ return $self->_literal_related('search', @_);
+}
+
+sub count_related {
+ my $self = shift;
+ return $self->_literal_related('count', @_);
+}
+
+sub _literal_related {
+ my $self = shift;
+ my $op = shift;
+ my $meth = "${op}_literal";
my $rel = shift;
my $attrs = { };
if (@_ > 1 && ref $_[$#_] eq 'HASH') {
$attrs = { %{ pop(@_) } };
}
my $rel_obj = $self->_relationships->{$rel};
- die "No such relationship ${rel}" unless $rel;
- $attrs = { %{$rel_obj->{attrs}}, %{$attrs || {}} };
+ $self->throw( "No such relationship ${rel}" ) unless $rel_obj;
+ $attrs = { %{$rel_obj->{attrs} || {}}, %{$attrs || {}} };
my $s_cond;
if (@_) {
- die "Invalid query: @_" if (@_ > 1 && (@_ % 2 == 1));
+ $self->throw( "Invalid query: @_" ) if (@_ > 1 && (@_ % 2 == 1));
my $query = ((@_ > 1) ? {@_} : shift);
$s_cond = $self->_cond_resolve($query, $attrs);
}
- $attrs->{_action} = 'convert';
+ $attrs->{_action} = 'convert'; # shouldn't we resolve the cond to something
+ # to merge into the AST really?
my ($cond) = $self->_cond_resolve($rel_obj->{cond}, $attrs);
$cond = "${s_cond} AND ${cond}" if $s_cond;
- return $rel_obj->{class}->retrieve_from_sql($cond, @{$attrs->{bind} || {}});
+ #warn $rel_obj->{class}." $meth $cond ".join(', ', @{$attrs->{bind}});
+ return $rel_obj->{class}->$meth($cond, @{$attrs->{bind} || []}, $attrs);
}
sub create_related {
+ my $class = shift;
+ return $class->new_related(@_)->insert;
+}
+
+sub new_related {
my ($self, $rel, $values, $attrs) = @_;
- die "Can't call create_related as class method" unless ref $self;
- die "create_related needs a hash" unless (ref $values eq 'HASH');
+ $self->throw( "Can't call new_related as class method" )
+ unless ref $self;
+ $self->throw( "new_related needs a hash" )
+ unless (ref $values eq 'HASH');
my $rel_obj = $self->_relationships->{$rel};
- die "No such relationship ${rel}" unless $rel;
- die "Can't abstract implicit create for ${rel}, condition not a hash"
+ $self->throw( "No such relationship ${rel}" ) unless $rel_obj;
+ $self->throw( "Can't abstract implicit create for ${rel}, condition not a hash" )
unless ref $rel_obj->{cond} eq 'HASH';
$attrs = { %{$rel_obj->{attrs}}, %{$attrs || {}}, _action => 'convert' };
my %fields = %$values;
$self->_cond_value($attrs, $k => $v);
$fields{$self->_cond_key($attrs, $k)} = (@{delete $attrs->{bind}})[0];
}
- return $rel_obj->{class}->create(\%fields);
+ return $rel_obj->{class}->new(\%fields);
+}
+
+sub find_or_create_related {
+ my $self = shift;
+ return ($self->search_related(@_))[0] || $self->create_related(@_);
+}
+
+sub set_from_related {
+ my ($self, $rel, $f_obj) = @_;
+ my $rel_obj = $self->_relationships->{$rel};
+ $self->throw( "No such relationship ${rel}" ) unless $rel_obj;
+ my $cond = $rel_obj->{cond};
+ $self->throw( "set_from_related can only handle a hash condition; the "
+ ."condition for $rel is of type ".(ref $cond ? ref $cond : 'plain scalar'))
+ unless ref $cond eq 'HASH';
+ $self->throw( "Object $f_obj isn't a ".$rel_obj->{class} )
+ unless $f_obj->isa($rel_obj->{class});
+ foreach my $key (keys %$cond) {
+ next if ref $cond->{$key}; # Skip literals and complex conditions
+ $self->throw("set_from_related can't handle $key as key")
+ unless $key =~ m/^foreign\.([^\.]+)$/;
+ my $val = $f_obj->get_column($1);
+ $self->throw("set_from_related can't handle ".$cond->{$key}." as value")
+ unless $cond->{$key} =~ m/^self\.([^\.]+)$/;
+ $self->set_column($1 => $val);
+ }
+ return 1;
+}
+
+sub update_from_related {
+ my $self = shift;
+ $self->set_from_related(@_);
+ $self->update;
}
1;
+
+=back
+
+=head1 AUTHORS
+
+Matt S. Trout <perl-stuff@trout.me.uk>
+
+=head1 LICENSE
+
+You may distribute this code under the same terms as Perl itself.
+
+=cut
+
projects / dbsrgits/DBIx-Class.git / blobdiff