X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FFilterColumn.pm;h=6d7e48c97c2eb507dd08f65c1def9c2d05160d7a;hb=dc6dadae6312ce97e6d85c343805ce940671d6e9;hp=9bea8a30548d95fb91ecf3c9fadea4ed5bae8e2c;hpb=cde96798a03e3e65b2bca2a3246164faab434a03;p=dbsrgits%2FDBIx-Class.git diff --git a/lib/DBIx/Class/FilterColumn.pm b/lib/DBIx/Class/FilterColumn.pm index 9bea8a3..6d7e48c 100644 --- a/lib/DBIx/Class/FilterColumn.pm +++ b/lib/DBIx/Class/FilterColumn.pm @@ -7,14 +7,22 @@ use base qw/DBIx::Class::Row/; sub filter_column { my ($self, $col, $attrs) = @_; + my $colinfo = $self->column_info($col); + + $self->throw_exception("FilterColumn can not be used on a column with a declared InflateColumn inflator") + if defined $colinfo->{_inflate_info} and $self->isa('DBIx::Class::InflateColumn'); + $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->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; } @@ -30,9 +38,8 @@ sub _column_from_storage { return $value unless exists $info->{_filter_info}; my $filter = $info->{_filter_info}{filter_from_storage}; - $self->throw_exception("No inflator for $col") unless defined $filter; - return $self->$filter($value); + return defined $filter ? $self->$filter($value) : $value; } sub _column_to_storage { @@ -44,8 +51,8 @@ sub _column_to_storage { return $value unless exists $info->{_filter_info}; my $unfilter = $info->{_filter_info}{filter_to_storage}; - $self->throw_exception("No unfilter for $col") unless defined $unfilter; - return $self->$unfilter($value); + + return defined $unfilter ? $self->$unfilter($value) : $value; } sub get_filtered_column { @@ -59,10 +66,38 @@ sub get_filtered_column { my $val = $self->get_column($col); - return $self->{_filtered_column}{$col} = $self->_column_from_storage($col, $val); + return $self->{_filtered_column}{$col} = $self->_column_from_storage( + $col, $val + ); +} + +sub get_column { + my ($self, $col) = @_; + + if (exists $self->{_filtered_column}{$col}) { + return $self->{_column_data}{$col} ||= $self->_column_to_storage ( + $col, $self->{_filtered_column}{$col} + ); + } + + return $self->next::method ($col); } -sub set_column { +# sadly a separate codepath in Row.pm ( used by insert() ) +sub get_columns { + my $self = shift; + + $self->{_column_data}{$_} = $self->_column_to_storage ( + $_, $self->{_filtered_column}{$_} + ) for grep + { ! exists $self->{_column_data}{$_} } + keys %{$self->{_filtered_column}||{}} + ; + + $self->next::method (@_); +} + +sub store_column { my ($self, $col) = (shift, @_); # blow cache @@ -71,49 +106,68 @@ sub set_column { $self->next::method(@_); } +sub has_column_loaded { + my ($self, $col) = @_; + return 1 if exists $self->{_filtered_column}{$col}; + return $self->next::method($col); +} + 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 + # unlike IC, FC does not need to deal with the 'filter' abomination + # thus we can short-curcuit filtering entirely and never call set_column + # in case this is already a dirty change OR the row never touched storage + if ( + ! $self->in_storage + or + $self->is_column_changed($col) + ) { + $self->make_column_dirty($col); + delete $self->{_column_data}{$col}; } + else { + $self->set_column($col, $self->_column_to_storage($col, $filtered)); + }; - $self->set_column($col, $self->_column_to_storage($col, $filtered)); - - return $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}; - $self->set_filtered_column($key, $val); - $attrs->{$key} = $self->_column_to_storage($key, $val) + my ($self, $data, @rest) = @_; + + foreach my $col (keys %{$data||{}}) { + if ( + $self->has_column($col) + && + exists $self->column_info($col)->{_filter_info} + ) { + $self->set_filtered_column($col, delete $data->{$col}); + + # FIXME update() reaches directly into the object-hash + # and we may *not* have a filtered value there - thus + # the void-ctx filter-trigger + $self->get_column($col) unless exists $self->{_column_data}{$col}; } } - return $self->next::method($attrs, @rest); + + return $self->next::method($data, @rest); } sub new { - my ($class, $attrs, @rest) = @_; - my $source = $attrs->{-result_source} + my ($class, $data, @rest) = @_; + my $source = $data->{-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 ($obj->has_column($key) && - exists $obj->column_info($key)->{_filter_info} ) { - my $val = delete $attrs->{$key}; - $obj->set_filtered_column($key, $val); + my $obj = $class->next::method($data, @rest); + + foreach my $col (keys %{$data||{}}) { + if ($obj->has_column($col) && + exists $obj->column_info($col)->{_filter_info} ) { + $obj->set_filtered_column($col, $data->{$col}); } } + return $obj; } @@ -125,7 +179,12 @@ DBIx::Class::FilterColumn - Automatically convert column data =head1 SYNOPSIS - # In your result classes +In your Schema or DB class add "FilterColumn" to the top of the component list. + + __PACKAGE__->load_components(qw( FilterColumn ... )); + +Set up filters for the columns you want to convert. + __PACKAGE__->filter_column( money => { filter_to_storage => 'to_pennies', filter_from_storage => 'from_pennies', @@ -137,6 +196,7 @@ DBIx::Class::FilterColumn - Automatically convert column data 1; + =head1 DESCRIPTION This component is meant to be a more powerful, but less DWIM-y, @@ -149,15 +209,23 @@ be done with L can be done with this component. =head2 filter_column __PACKAGE__->filter_column( colname => { - filter_from_storage => 'method', - filter_to_storage => 'method', + filter_from_storage => 'method'|\&coderef, + filter_to_storage => 'method'|\&coderef, }) -This is the method that you need to call to set up a filtered column. It takes -exactly two arguments; the first being the column name the second being a -C with C and C having -something that can be called as a method. The method will be called with -the value of the column as the first non-C<$self> argument. +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 and C set to either +a method name or a code reference. In either case the filter is invoked as: + + $result->$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 @@ -170,3 +238,22 @@ Returns the filtered value of the 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). + +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 is not required, as just +passing the database value through to perl does the right thing.