Deprecate UTF8Columns with a lot of warning whistles

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / UTF8Columns.pm

diff --git a/lib/DBIx/Class/UTF8Columns.pm b/lib/DBIx/Class/UTF8Columns.pm
index 7e21502..9a54e5b 100644 (file)
--- a/lib/DBIx/Class/UTF8Columns.pm
+++ b/lib/DBIx/Class/UTF8Columns.pm
@@ -2,13 +2,12 @@ package DBIx::Class::UTF8Columns;
 use strict;
 use warnings;
 use base qw/DBIx::Class/;
-use utf8;
 
 __PACKAGE__->mk_classdata( '_utf8_columns' );
 
 =head1 NAME
 
-DBIx::Class::UTF8Columns - Force UTF8 (Unicode) flag on columns
+DBIx::Class::UTF8Columns - Force UTF8 (Unicode) flag on columns (DEPRECATED)
 
 =head1 SYNOPSIS
 
@@ -24,9 +23,54 @@ DBIx::Class::UTF8Columns - Force UTF8 (Unicode) flag on columns
 
 =head1 DESCRIPTION
 
-This module allows you to get columns data that have utf8 (Unicode) flag.
+This module allows you to get and store utf8 (unicode) column data
+in a database that does not natively support unicode. It ensures
+that column data is correctly serialised as a byte stream when
+stored and de-serialised to unicode strings on retrieval.
 
-=head2 Warning
+  THE USE OF THIS MODULE (AND ITS COUSIN DBIx::Class::ForceUTF8) IS VERY
+  STRONGLY DISCOURAGED, PLEASE READ THE WARNINGS BELOW FOR AN EXPLANATION.
+
+If you want to continue using this module and do not want to recieve
+further warnings set the environmane variable C<DBIC_UTF8COLUMNS_OK>
+to a true value.
+
+=head2 Warning - Module does not function properly on create/insert
+
+Recently (April 2010) a bug was found deep in the core of L<DBIx::Class>
+which affects any component attempting to perform encoding/decoding by
+overloading L<store_column|DBIx::Class::Row/store_column> and
+L<get_columns|DBIx::Class::Row/get_columns>. As a result of this problem
+L<create|DBIx::Class::ResultSet/create> sends the original column values
+to the database, while L<update|DBIx::Class::ResultSet/update> sends the
+encoded values. L<DBIx::Class::UTF8Columns> and L<DBIx::Class::ForceUTF8>
+are both affected by ths bug.
+
+It is unclear how this bug went undetected for so long (it was
+introduced in March 2006), No attempts to fix it will be made while the
+implications of changing such a fundamental behavior of DBIx::Class are
+being evaluated. However in this day and age you should not be using
+this module anyway as Unicode is properly supported by all major
+database engines, as explained below.
+
+If you have specific questions about the integrity of your data in light
+of this development - please 
+L<join us on IRC or the mailing list|DBIx::Class/GETTING HELP/SUPPORT>
+to further discuss your concerns with the team.
+
+=head2 Warning - Native Database Unicode Support
+
+If your database natively supports Unicode (as does SQLite with the
+C<sqlite_unicode> connect flag, MySQL with C<mysql_enable_utf8>
+connect flag or Postgres with the C<pg_enable_utf8> connect flag),
+then this component should B<not> be used, and will corrupt unicode
+data in a subtle and unexpected manner.
+
+It is far better to do Unicode support within the database if
+possible rather than converting data to and from raw bytes on every
+database round trip.
+
+=head2 Warning - Component Overloading
 
 Note that this module overloads L<DBIx::Class::Row/store_column> in a way
 that may prevent other components overloading the same method from working
@@ -114,7 +158,8 @@ sub store_column {
 
 # override this if you want to force everything to be encoded/decoded
 sub _is_utf8_column {
-  return (shift->utf8_columns || {})->{shift};
+  # my ($self, $col) = @_;
+  return ($_[0]->utf8_columns || {})->{$_[1]};
 }
 
 =head1 AUTHORS