- Added some stuff to MANIFEST.SKIP

[dbsrgits/SQL-Translator.git] / lib / SQL / Translator / Parser / XML / XMI / SQLFairy.pm

diff --git a/lib/SQL/Translator/Parser/XML/XMI/SQLFairy.pm b/lib/SQL/Translator/Parser/XML/XMI/SQLFairy.pm
index 6bf9c3b..d66b42c 100644 (file)
--- a/lib/SQL/Translator/Parser/XML/XMI/SQLFairy.pm
+++ b/lib/SQL/Translator/Parser/XML/XMI/SQLFairy.pm
@@ -1,7 +1,7 @@
 package SQL::Translator::Parser::XML::XMI::SQLFairy;
 
 # -------------------------------------------------------------------
-# $Id: SQLFairy.pm,v 1.2 2003-10-13 17:05:55 grommit Exp $
+# $Id$
 # -------------------------------------------------------------------
 # Copyright (C) 2003 Mark Addison <mark.addison@itn.co.uk>,
 #
@@ -29,7 +29,7 @@ SQL::Translator::Parser::XML::XMI::SQLFairy - Create Schema from UML Models.
 use strict;
 
 use vars qw[ $DEBUG $VERSION @EXPORT_OK ];
-$VERSION = sprintf "%d.%02d", q$Revision: 1.2 $ =~ /(\d+)\.(\d+)/;
+$VERSION = sprintf "%d.%02d", q$Revision$ =~ /(\d+)\.(\d+)/;
 $DEBUG   = 0 unless defined $DEBUG;
 use Exporter;
 use base qw(Exporter);
@@ -145,13 +145,11 @@ sub classes2schema {
             $end[0]->{multiplicity}{rangeUpper} == 1
             || $end[1]->{multiplicity}{rangeUpper} == 1
         ) {
-            # 1:m or 0:m
             one2many($assoc);
         }
         else
         {
-            # m:n
-            warn "Sorry, n:m associations not yet implimented for xmi.id=".$assoc->{"xmi.id"}."\n";
+            many2many($assoc);
         }
 
     }
@@ -232,7 +230,8 @@ sub add_pkey {
 }
 
 # Maps a 1:M association into the schema
-sub one2many {
+sub one2many
+{
     my ($assoc) = @_;
     my @ends = @{$assoc->{associationEnds}};
     my ($end1) = grep $_->{multiplicity}{rangeUpper} == 1, @ends;
@@ -272,6 +271,48 @@ sub one2many {
     ) or die $schema->error;
 }
 
+# Maps m:n into schema by building a link table.
+sub many2many
+{
+    my ($assoc) = @_;
+    my @end = @{$assoc->{associationEnds}};
+
+    # Create the link table
+    my $name = $end[0]->{participant}{name}."_".$end[1]->{participant}{name};
+    my $link_table = $schema->add_table( name => $name )
+    or die "Schema Error: ".$schema->error;
+
+    # Export the pkey(s) from the ends into the link table
+    my @pkeys;
+    foreach (@end) {
+        my $table = $schema->get_table($_->{participant}{name});
+        my @fkeys = $table->primary_key->fields;
+        push @pkeys,@fkeys;
+        foreach ( @fkeys ) {
+            my $fld = $table->get_field($_);
+            my %data;
+            $data{$_} = $fld->$_()
+                foreach (
+                qw/name size data_type default_value is_nullable is_unique/);
+            $data{is_auto_increment} = 0;
+            $data{extra} = { $fld->extra }; # Copy
+            $link_table->add_field(%data) or die $table->error;
+        }
+        $link_table->add_constraint(
+            type   => "FOREIGN_KEY",
+            fields => [@fkeys],
+            reference_table => $table->{name},
+            reference_fields => [@fkeys],
+        ) or die $schema->error;
+
+    }
+    # Add pkey constraint
+    $link_table->add_constraint( type => "PRIMARY KEY", fields => [@pkeys] )
+    or die $link_table->error;
+
+
+    # Add fkeys to our participants
+}
 1; #---------------------------------------------------------------------------
 
 __END__
@@ -353,8 +394,9 @@ contains an attribute that makes a good candidate for a pkey, e.g. email.
 
 =head2 Relationships
 
-Modeled using UML associations. Currently only handles 0:m and 1:m joins. That
-is associations where one ends multiplicty is '1' or '0..1' and the other end's
+=head2 1:m
+
+Associations where one ends multiplicty is '1' or '0..1' and the other end's
 multplicity is more than 1 e.g '*', '0..*', '1..*', '0..3', '4..42' etc.
 
 The pkey field from the 1 end is added to the table for the class at the many
@@ -366,6 +408,12 @@ nullable, if its multiplicity '1' (1:m) then its made not nullable.
 If the association is a composition then the created fkey is made part of the
 many ends pkey. ie It exports the pkey to create an identity join.
 
+=head2 m:n
+
+Model using a standard m:n association and the parser will automatically create
+a link table for you in the Schema by exporting pkeys from the tables at 
+each end.
+
 =head1 EXAMPLE
 
 TODO An example to help make sense of the above! Probably based on the test.
@@ -376,11 +424,15 @@ TODO An example to help make sense of the above! Probably based on the test.
 
 =head1 TODO
 
-1:1 and m:m joins.
+1:1 joins.
+
+Use Role names from associations as field names for exported keys when building
+relationships.
 
 Generalizations.
 
-Support for the format_X_name subs in the Translator.
+Support for the format_X_name subs in the Translator and format subs for 
+generating the link table name in m:n joins.
 
 Lots more...