Commit | Line | Data |
5ef62e9f |
1 | package |
2 | DBIx::Class::CDBICompat::ColumnsAsHash; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
7 | use Scalar::Defer; |
8 | use Scalar::Util qw(weaken); |
9 | use Carp; |
10 | |
11 | |
12 | =head1 NAME |
13 | |
14 | DBIx::Class::CDBICompat::ColumnsAsHash |
15 | |
16 | =head1 SYNOPSIS |
17 | |
18 | See DBIx::Class::CDBICompat for directions for use. |
19 | |
20 | =head1 DESCRIPTION |
21 | |
22 | Emulates the I<undocumnted> behavior of Class::DBI where the object can be accessed as a hash of columns. This is often used as a performance hack. |
23 | |
24 | my $column = $row->{column}; |
25 | |
26 | =head2 Differences from Class::DBI |
27 | |
28 | This will warn when a column is accessed as a hash key. |
29 | |
30 | =cut |
31 | |
32 | sub new { |
33 | my $class = shift; |
34 | |
35 | my $new = $class->next::method(@_); |
36 | |
37 | $new->_make_columns_as_hash; |
38 | |
39 | return $new; |
40 | } |
41 | |
42 | sub inflate_result { |
43 | my $class = shift; |
44 | |
45 | my $new = $class->next::method(@_); |
46 | |
47 | $new->_make_columns_as_hash; |
48 | |
49 | return $new; |
50 | } |
51 | |
52 | |
53 | sub _make_columns_as_hash { |
54 | my $self = shift; |
55 | |
56 | weaken $self; |
57 | for my $col ($self->columns) { |
58 | if( exists $self->{$col} ) { |
59 | warn "Skipping mapping $col to a hash key because it exists"; |
60 | } |
61 | |
62 | next unless $self->can($col); |
63 | $self->{$col} = defer { |
64 | my $class = ref $self; |
65 | carp "Column '$col' of '$class/$self' was accessed as a hash"; |
66 | $self->$col(); |
67 | }; |
68 | } |
69 | } |
70 | |
71 | sub update { |
72 | my $self = shift; |
73 | |
74 | for my $col ($self->columns) { |
75 | if( $self->_hash_changed($col) ) { |
76 | my $class = ref $self; |
77 | carp "Column '$col' of '$class/$self' was updated as a hash"; |
78 | $self->$col($self->_get_column_from_hash($col)); |
79 | $self->{$col} = defer { $self->$col() }; |
80 | } |
81 | } |
82 | |
83 | return $self->next::method(@_); |
84 | } |
85 | |
86 | sub _hash_changed { |
87 | my($self, $col) = @_; |
88 | |
89 | return 0 unless exists $self->{$col}; |
90 | |
91 | my $hash = $self->_get_column_from_hash($col); |
92 | my $obj = $self->$col(); |
93 | |
94 | return 1 if defined $hash xor defined $obj; |
95 | return 0 if !defined $hash and !defined $obj; |
96 | return 1 if $hash ne $obj; |
97 | return 0; |
98 | } |
99 | |
100 | # get the column value without a warning |
101 | sub _get_column_from_hash { |
102 | my($self, $col) = @_; |
103 | |
104 | local $SIG{__WARN__} = sub {}; |
105 | return force $self->{$col}; |
106 | } |
107 | |
108 | 1; |