Emulate $CDBI::Weaken_Not_Available and CDBI::Plugin::NoCache

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

diff --git a/lib/DBIx/Class/CDBICompat.pm b/lib/DBIx/Class/CDBICompat.pm
index daf5822..49988c9 100644 (file)
--- a/lib/DBIx/Class/CDBICompat.pm
+++ b/lib/DBIx/Class/CDBICompat.pm
@@ -2,13 +2,19 @@ package DBIx::Class::CDBICompat;
 
 use strict;
 use warnings;
-use base qw/DBIx::Class/;
+use base qw/DBIx::Class::Core DBIx::Class::DB/;
+use Carp::Clan qw/^DBIx::Class/;
+
+eval {
+  require Class::Trigger;
+  require DBIx::ContextualFetch;
+};
+croak "Class::Trigger and DBIx::ContextualFetch is required for CDBICompat" if $@;
 
 __PACKAGE__->load_own_components(qw/
   Constraints
   Triggers
   ReadOnly
-  GetSet
   LiveObjectIndex
   AttributeAPI
   Stringify
@@ -16,22 +22,27 @@ __PACKAGE__->load_own_components(qw/
   Constructor
   AccessorMapping
   ColumnCase
-  HasMany
-  HasA
+  Relationships
+  Copy
   LazyLoading
   AutoUpdate
   TempColumns
+  GetSet
   Retrieve
   Pager
   ColumnGroups
-  ImaDBI/);
+  ColumnsAsHash
+  AbstractSearch
+  ImaDBI
+  Iterator
+/);
 
             #DBIx::Class::ObjIndexStubs
 1;
 
-=head1 NAME 
+=head1 NAME
 
-DBIx::Class::CDBICompat - Class::DBI Compatability layer.
+DBIx::Class::CDBICompat - Class::DBI Compatibility layer.
 
 =head1 SYNOPSIS
 
@@ -40,15 +51,16 @@ DBIx::Class::CDBICompat - Class::DBI Compatability layer.
 
 =head1 DESCRIPTION
 
-DBIx::Class features a fully featured compability layer with L<Class::DBI>
-to ease transition for existing CDBI users. In fact, this class is just a
-receipe containing all the features emulated. If you like, you can choose
-which features to emulate by building your own class and loading it like 
-this:
+DBIx::Class features a fully featured compatibility layer with L<Class::DBI>
+and L<Class::DBI::AbstractSearch> to ease transition for existing CDBI users. 
+
+In fact, this class is just a receipe containing all the features emulated.
+If you like, you can choose which features to emulate by building your 
+own class and loading it like this:
 
   __PACKAGE__->load_own_components(qw/CDBICompat/);
 
-this will automatically load the features included in My::DB::CDBICompat, 
+this will automatically load the features included in My::DB::CDBICompat,
 provided it looks something like this:
 
   package My::DB::CDBICompat;
@@ -60,70 +72,62 @@ provided it looks something like this:
     CDBICompat::MightHave
   /);
 
-=head1 Components
-
-=over 4
-
-=item AccessorMapping
-
-=item AttributeAPI
 
-=item AutoUpdate
+=head1 LIMITATIONS
 
-Allows you to turn on automatic updates for column values.
+=head2 Unimplemented
 
-=item ColumnCase
+The following methods and classes are not emulated, maybe in the future.
 
-=item ColumnGroups
-
-=item Constraints
-
-=item Constructor
-
-=item DestroyWarning
-
-=item GetSet
+=over 4
 
-=item HasA
+=item Class::DBI::Query
 
-Responsible for HasA relationships. 
+Deprecated in Class::DBI.
 
-=item HasMany
+=item Class::DBI::Column
 
-Responsible for HasMany relationships. 
+Not documented in Class::DBI.  CDBICompat's columns() returns a plain string, not an object.
 
-=item ImaDBI
+=item data_type()
 
-=item LazyLoading
+Undocumented CDBI method.
 
-=item LiveObjectIndex
+=back
 
-The live object index tries to ensure there is only one version of a object
-in the perl interprenter.
+=head2 Limited Support
 
-=item MightHave
+The following elements of Class::DBI have limited support.
 
-Responsible for MightHave relationships. 
+=over 4
 
-=item ObjIndexStubs
+=item Class::DBI::Relationship
 
-=item ReadOnly
+The semi-documented Class::DBI::Relationship objects returned by C<meta_info($type, $col)> are mostly emulated except for their C<args> method.
 
-=item Retrieve
+=item Relationships
 
-=item Stringify
+Relationships between tables (has_a, has_many...) must be delcared after all tables in the relationship have been declared.  Thus the usual CDBI idiom of declaring columns and relationships for each class together will not work.  They must instead be done like so:
 
-=item TempColumns
+    package Foo;
+    use base qw(Class::DBI);
+    
+    Foo->table("foo");
+    Foo->columns( All => qw(this that bar) );
 
-=item Triggers
+    package Bar;
+    use base qw(Class::DBI);
+    
+    Bar->table("bar");
+    Bar->columns( All => qw(up down) );
 
-This class implements the trigger functionality.
+    # Now that Foo and Bar are declared it is safe to declare a
+    # relationship between them
+    Foo->has_a( bar => "Bar" );
 
-=item PassThrough
 
 =back
 
-
 =head1 AUTHORS
 
 Matt S. Trout <mst@shadowcatsystems.co.uk>