package DBIx::Class::FilterColumn;
-
use strict;
use warnings;
sub filter_column {
my ($self, $col, $attrs) = @_;
+ my $colinfo = $self->column_info($col);
+
+ $self->throw_exception('FilterColumn does not work with InflateColumn')
+ if $self->isa('DBIx::Class::InflateColumn') &&
+ defined $colinfo->{_inflate_info};
+
$self->throw_exception("No such column $col to filter")
unless $self->has_column($col);
- $self->throw_exception("filter_column needs attr hashref")
+ $self->throw_exception('filter_column expects a hashref of filter specifications')
unless ref $attrs eq 'HASH';
- $self->column_info($col)->{_filter_info} = $attrs;
- my $acc = $self->column_info($col)->{accessor};
- $self->mk_group_accessors('value' => [ (defined $acc ? $acc : $col), $col]);
+ $self->throw_exception('An invocation of filter_column() must specify either a filter_from_storage or filter_to_storage')
+ unless $attrs->{filter_from_storage} || $attrs->{filter_to_storage};
+
+ $colinfo->{_filter_info} = $attrs;
+ my $acc = $colinfo->{accessor};
+ $self->mk_group_accessors(filtered_column => [ (defined $acc ? $acc : $col), $col]);
return 1;
}
-sub _filtered_column {
+sub _column_from_storage {
my ($self, $col, $value) = @_;
return $value unless defined $value;
return $value unless exists $info->{_filter_info};
- my $filter = $info->{_filter_info}{filter};
- $self->throw_exception("No inflator for $col") unless defined $filter;
+ my $filter = $info->{_filter_info}{filter_from_storage};
- return $self->$filter($value);
+ return defined $filter ? $self->$filter($value) : $value;
}
-sub _unfiltered_column {
+sub _column_to_storage {
my ($self, $col, $value) = @_;
my $info = $self->column_info($col) or
return $value unless exists $info->{_filter_info};
- my $unfilter = $info->{_filter_info}{unfilter};
- $self->throw_exception("No unfilter for $col") unless defined $unfilter;
- return $self->$unfilter($value);
+ my $unfilter = $info->{_filter_info}{filter_to_storage};
+
+ return defined $unfilter ? $self->$unfilter($value) : $value;
}
-sub get_value {
+sub get_filtered_column {
my ($self, $col) = @_;
$self->throw_exception("$col is not a filtered column")
my $val = $self->get_column($col);
- return $self->{_filtered_column}{$col} = $self->_filtered_column($col, $val);
+ return $self->{_filtered_column}{$col} = $self->_column_from_storage($col, $val);
}
-sub set_value {
- my ($self, $col, $filtered) = @_;
+sub get_column {
+ my ($self, $col) = @_;
+ if (exists $self->{_filtered_column}{$col}) {
+ return $self->{_column_data}{$col} ||= $self->_column_to_storage ($col, $self->{_filtered_column}{$col});
+ }
- $self->set_column($col, $self->_unfiltered_column($col, $filtered));
+ return $self->next::method ($col);
+}
+
+# sadly a separate codepath in Row.pm ( used by insert() )
+sub get_columns {
+ my $self = shift;
+
+ foreach my $col (keys %{$self->{_filtered_column}||{}}) {
+ $self->{_column_data}{$col} ||= $self->_column_to_storage ($col, $self->{_filtered_column}{$col})
+ if exists $self->{_filtered_column}{$col};
+ }
+ $self->next::method (@_);
+}
+
+sub store_column {
+ my ($self, $col) = (shift, @_);
+
+ # blow cache
delete $self->{_filtered_column}{$col};
- return $filtered;
+ $self->next::method(@_);
+}
+
+sub set_filtered_column {
+ my ($self, $col, $filtered) = @_;
+
+ # do not blow up the cache via set_column unless necessary
+ # (filtering may be expensive!)
+ if (exists $self->{_filtered_column}{$col}) {
+ return $filtered
+ if ($self->_eq_column_values ($col, $filtered, $self->{_filtered_column}{$col} ) );
+
+ $self->make_column_dirty ($col); # so the comparison won't run again
+ }
+
+ $self->set_column($col, $self->_column_to_storage($col, $filtered));
+
+ return $self->{_filtered_column}{$col} = $filtered;
}
sub update {
my ($self, $attrs, @rest) = @_;
+
foreach my $key (keys %{$attrs||{}}) {
- if ($self->has_column($key) &&
- exists $self->column_info($key)->{_filter_info}) {
- my $val = delete $attrs->{$key};
- $self->set_value($key, $val);
- $attrs->{$key} = $self->_unfiltered_column($key, $val)
+ if (
+ $self->has_column($key)
+ &&
+ exists $self->column_info($key)->{_filter_info}
+ ) {
+ $self->set_filtered_column($key, delete $attrs->{$key});
+
+ # FIXME update() reaches directly into the object-hash
+ # and we may *not* have a filtered value there - thus
+ # the void-ctx filter-trigger
+ $self->get_column($key) unless exists $self->{_column_data}{$key};
}
}
+
return $self->next::method($attrs, @rest);
}
-
sub new {
my ($class, $attrs, @rest) = @_;
- my $filtered;
+ my $source = $attrs->{-result_source}
+ or $class->throw_exception('Sourceless rows are not supported with DBIx::Class::FilterColumn');
+
+ my $obj = $class->next::method($attrs, @rest);
foreach my $key (keys %{$attrs||{}}) {
- if ($class->has_column($key) &&
- exists $class->column_info($key)->{_filter_info} ) {
- $attrs->{$key} = $class->_unfiltered_column($key, delete $attrs->{$key})
+ if ($obj->has_column($key) &&
+ exists $obj->column_info($key)->{_filter_info} ) {
+ $obj->set_filtered_column($key, $attrs->{$key});
}
}
- my $obj = $class->next::method($attrs, @rest);
+
return $obj;
}
-
1;
+
+=head1 NAME
+
+DBIx::Class::FilterColumn - Automatically convert column data
+
+=head1 SYNOPSIS
+
+In your Schema or DB class add "FilterColumn" to the top of the component list.
+
+ __PACKAGE__->load_components(qw( FilterColumn ... ));
+
+Set up filters for the columns you want to convert.
+
+ __PACKAGE__->filter_column( money => {
+ filter_to_storage => 'to_pennies',
+ filter_from_storage => 'from_pennies',
+ });
+
+ sub to_pennies { $_[1] * 100 }
+
+ sub from_pennies { $_[1] / 100 }
+
+ 1;
+
+
+=head1 DESCRIPTION
+
+This component is meant to be a more powerful, but less DWIM-y,
+L<DBIx::Class::InflateColumn>. One of the major issues with said component is
+that it B<only> works with references. Generally speaking anything that can
+be done with L<DBIx::Class::InflateColumn> can be done with this component.
+
+=head1 METHODS
+
+=head2 filter_column
+
+ __PACKAGE__->filter_column( colname => {
+ filter_from_storage => 'method'|\&coderef,
+ filter_to_storage => 'method'|\&coderef,
+ })
+
+This is the method that you need to call to set up a filtered column. It takes
+exactly two arguments; the first being the column name the second being a hash
+reference with C<filter_from_storage> and C<filter_to_storage> set to either
+a method name or a code reference. In either case the filter is invoked as:
+
+ $row_obj->$filter_specification ($value_to_filter)
+
+with C<$filter_specification> being chosen depending on whether the
+C<$value_to_filter> is being retrieved from or written to permanent
+storage.
+
+If a specific directional filter is not specified, the original value will be
+passed to/from storage unfiltered.
+
+=head2 get_filtered_column
+
+ $obj->get_filtered_column('colname')
+
+Returns the filtered value of the column
+
+=head2 set_filtered_column
+
+ $obj->set_filtered_column(colname => 'new_value')
+
+Sets the filtered value of the column
+
+=head1 EXAMPLE OF USE
+
+Some databases have restrictions on values that can be passed to
+boolean columns, and problems can be caused by passing value that
+perl considers to be false (such as C<undef>).
+
+One solution to this is to ensure that the boolean values are set
+to something that the database can handle - such as numeric zero
+and one, using code like this:-
+
+ __PACKAGE__->filter_column(
+ my_boolean_column => {
+ filter_to_storage => sub { $_[1] ? 1 : 0 },
+ }
+ );
+
+In this case the C<filter_from_storage> is not required, as just
+passing the database value through to perl does the right thing.
projects / dbsrgits/DBIx-Class.git / blobdiff