X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FResultSource%2FMultipleTableInheritance.pm;h=f05b19b2ff0f88ae593b8e802e020394e0f16ddb;hb=4e4f71e3a8b42cf7b011620ea244891c943b12d5;hp=f27eab6726a58c0351d535eceb145c5b5e3fe876;hpb=7abe3af2b03bc2dd077403ef7e59d9252a5f5817;p=dbsrgits%2FDBIx-Class-ResultSource-MultipleTableInheritance.git

diff --git a/lib/DBIx/Class/ResultSource/MultipleTableInheritance.pm b/lib/DBIx/Class/ResultSource/MultipleTableInheritance.pm
index f27eab6..f05b19b 100644
--- a/lib/DBIx/Class/ResultSource/MultipleTableInheritance.pm
+++ b/lib/DBIx/Class/ResultSource/MultipleTableInheritance.pm
@@ -7,6 +7,8 @@ use Method::Signatures::Simple;
 use Carp::Clan qw/^DBIx::Class/;
 use aliased 'DBIx::Class::ResultSource::Table';
 use aliased 'DBIx::Class::ResultClass::HashRefInflator';
+use String::TT qw(strip tt);
+use Scalar::Util qw(blessed);
 use namespace::autoclean;
 
 # how this works:
@@ -24,7 +26,7 @@ use namespace::autoclean;
 #
 # deploying the postgres rules through SQLT may be a pain though.
 
-__PACKAGE__->mk_group_accessors(simple => qw(parent_source));
+__PACKAGE__->mk_group_accessors(simple => qw(parent_source additional_parents));
 
 method new ($class: @args) {
   my $new = $class->next::method(@args);
@@ -39,22 +41,79 @@ method new ($class: @args) {
   return $new;
 }
 
+method add_additional_parents (@classes) {
+  foreach my $class (@classes) {
+    Class::C3::Componentised->ensure_class_loaded($class);
+    $self->add_additional_parent(
+      $class->result_source_instance
+    );
+  }
+}
+
+method add_additional_parent ($source) {
+  my ($our_pk, $their_pk) = map {
+    join('|',sort $_->primary_columns)
+  } ($self, $source);
+
+  confess "Can't attach additional parent ${\$source->name} - it has different PKs ($their_pk versus our $our_pk)"
+    unless $their_pk eq $our_pk;
+  $self->additional_parents([
+    @{$self->additional_parents||[]}, $source
+  ]);
+  $self->add_columns(
+    map {
+      $_ => # put the extra key first to default it
+      { originally_defined_in => $source->name, %{$source->column_info($_)}, },
+    } grep !$self->has_column($_), $source->columns
+  );
+  foreach my $rel ($source->relationships) {
+    my $rel_info = $source->relationship_info($rel);
+    $self->add_relationship(
+      $rel, $rel_info->{source}, $rel_info->{cond},
+      # extra key first to default it
+      {originally_defined_in => $source->name, %{$rel_info->{attrs}}},
+    );
+  }
+  { no strict 'refs';
+    push(@{$self->result_class.'::ISA'}, $source->result_class);
+  }
+}
+
+method _source_by_name ($name) {
+  my $schema = $self->schema;
+  my ($source) = 
+    grep { $_->name eq $name }
+      map $schema->source($_), $schema->sources;
+  confess "Couldn't find attached source for parent $name - did you use load_classes? This module is only compatible with load_namespaces"
+    unless $source;
+  return $source;
+}
+
 method schema (@args) {
   my $ret = $self->next::method(@args);
   if (@args) {
-    $self->_attach_additional_sources;
+    if ($self->parent_source) {
+      my $parent_name = $self->parent_source->name;
+      $self->parent_source($self->_source_by_name($parent_name));
+    }
+    $self->additional_parents([
+      map { $self->_source_by_name($_->name) }
+      @{$self->additional_parents||[]}
+    ]);
   }
   return $ret;
 }
 
-method _attach_additional_sources () {
-  my $raw_name = $self->_raw_source_name;
+method attach_additional_sources () {
+  my $raw_name = $self->raw_source_name;
   my $schema = $self->schema;
 
   # if the raw source is already present we can assume we're done
   return if grep { $_ eq $raw_name } $schema->sources;
+
   # our parent should've been registered already actually due to DBIC
   # attaching subclass sources later in load_namespaces
+
   my $parent;
   if ($self->parent_source) {
       my $parent_name = $self->parent_source->name;
@@ -63,26 +122,96 @@ method _attach_additional_sources () {
         map $schema->source($_), $schema->sources;
     confess "Couldn't find attached source for parent $parent_name - did you use load_classes? This module is only compatible with load_namespaces"
       unless $parent;
+    $self->parent_source($parent); # so our parent is the one in this schema
   }
-  my $table = Table->new({ name => '_'.$self->name });
-  $table->add_columns(
-    map { ($_ => { %{$self->column_info($_)} }) }
-      grep { $self->column_info($_)->{originally_defined_in} eq $self->name }
-        $self->columns
-  );
+
+  # create the raw table source
+
+  my $table = Table->new({ name => $self->raw_table_name });
+
   # we don't need to add the PK cols explicitly if we're the root table
-  # since they already got added above
+  # since they'll get added below
+
+  my %pk_join;
+
   if ($parent) {
-    my %join;
     foreach my $pri ($self->primary_columns) {
       my %info = %{$self->column_info($pri)};
       delete @info{qw(is_auto_increment sequence auto_nextval)};
       $table->add_column($pri => \%info);
-      $join{"foreign.${pri}"} = "self.${pri}";
+      $pk_join{"foreign.${pri}"} = "self.${pri}";
     }
-    $table->add_relationship('parent', $parent->source_name, \%join);
+    # have to use source name lookups rather than result class here
+    # because we don't actually have a result class on the raw sources
+    $table->add_relationship('parent', $parent->raw_source_name, \%pk_join);
+    $self->depends_on->{$parent->source_name} = 1;
+  }
+
+  foreach my $add (@{$self->additional_parents||[]}) {
+    $table->add_relationship(
+      'parent_'.$add->name, $add->source_name, \%pk_join
+    );
+    $self->depends_on->{$add->source_name} = 1;
   }
+
+  # add every column that's actually a concrete part of us
+
+  $table->add_columns(
+    map { ($_ => { %{$self->column_info($_)} }) }
+      grep { $self->column_info($_)->{originally_defined_in} eq $self->name }
+        $self->columns
+  );
   $table->set_primary_key($self->primary_columns);
+
+  # we need to copy our rels to the raw object as well
+  # note that ->add_relationship on a source object doesn't create an
+  # accessor so we can leave that part in the attributes
+
+  # if the other side is a table then we need to copy any rels it has
+  # back to us, as well, so that they point at the raw table. if the
+  # other side is an MTI view then we need to create the rels to it to
+  # point at -its- raw table; we don't need to worry about backrels because
+  # it's going to run this method too (and its raw source might not exist
+  # yet so we can't, anyway)
+
+  foreach my $rel ($self->relationships) {
+    my $rel_info = $self->relationship_info($rel);
+
+    # if we got this from the superclass, -its- raw table will nail this.
+    # if we got it from an additional parent, it's its problem.
+    next unless $rel_info->{attrs}{originally_defined_in} eq $self->name;
+
+    my $f_source = $schema->source($rel_info->{source});
+
+    # __PACKAGE__ is correct here because subclasses should be caught
+
+    my $one_of_us = $f_source->isa(__PACKAGE__);
+
+    my $f_source_name = $f_source->${\
+                        ($one_of_us ? 'raw_source_name' : 'source_name')
+                      };
+    
+    $table->add_relationship(
+      '_'.$rel, $f_source_name, @{$rel_info}{qw(cond attrs)}
+    );
+
+    unless ($one_of_us) {
+      my $reverse = do {
+        # we haven't been registered yet, so reverse_ cries
+        # XXX this is evil and will probably break eventually
+        local @{$schema->source_registrations}
+               {map $self->$_, qw(source_name result_class)}
+          = ($self, $self);
+        $self->reverse_relationship_info($rel);
+      };
+      foreach my $rev_rel (keys %$reverse) {
+        $f_source->add_relationship(
+          '_raw_'.$rev_rel, $raw_name, @{$reverse->{$rev_rel}}{qw(cond attrs)}
+        );
+      }
+    }
+  }
+
   $schema->register_source($raw_name => $table);
 }
 
@@ -93,17 +222,202 @@ method set_primary_key (@args) {
   return $self->next::method(@args);
 }
 
-method _raw_source_name () {
+method raw_source_name () {
   my $base = $self->source_name;
-  confess "Can't generate raw source name when we don't have a source_name"
+  confess "Can't generate raw source name for ${\$self->name} when we don't have a source_name"
     unless $base;
   return 'Raw::'.$base;
 }
 
+method raw_table_name () {
+  return '_'.$self->name;
+}
+
 method add_columns (@args) {
   my $ret = $self->next::method(@args);
   $_->{originally_defined_in} ||= $self->name for values %{$self->_columns};
   return $ret;
 }
 
+method add_relationship ($name, $f_source, $cond, $attrs) {
+  $self->next::method(
+    $name, $f_source, $cond,
+    { originally_defined_in => $self->name, %{$attrs||{}}, }
+  );
+}
+
+BEGIN {
+
+  # helper routines, constructed as anon subs so autoclean nukes them
+
+  use signatures;
+
+  *argify = sub (@names) {
+    map '_'.$_, @names;
+  };
+
+  *qualify_with = sub ($source, @names) {
+    my $name = blessed($source) ? $source->name : $source;
+    map join('.', $name, $_), @names;
+  };
+
+  *body_cols = sub ($source) {
+    my %pk; @pk{$source->primary_columns} = ();
+    map +{ %{$source->column_info($_)}, name => $_ },
+      grep !exists $pk{$_}, $source->columns;
+  };
+
+  *pk_cols = sub ($source) {
+    map +{ %{$source->column_info($_)}, name => $_ },
+      $source->primary_columns;
+  };
+
+  *names_of = sub (@cols) { map $_->{name}, @cols };
+
+  *function_body = sub ($name, $args, $body_parts) {
+    my $arglist = join(
+      ', ',
+        map "_${\$_->{name}} ${\uc($_->{data_type})}",
+          @$args
+    );
+    my $body = join("\n", '', map "          $_;", @$body_parts);
+    return strip tt q{
+      CREATE OR REPLACE FUNCTION [% name %]
+        ([% arglist %])
+        RETURNS VOID AS $function$
+        BEGIN
+          [%- body %]
+        END;
+      $function$ LANGUAGE plpgsql;
+    };
+  };
+}
+
+BEGIN {
+
+  use signatures;
+
+  *arg_hash = sub ($source) {
+    map +($_ => \(argify $_)), names_of body_cols $source;
+  };
+
+  *rule_body = sub ($on, $to, $oldlist, $newlist) {
+    my $arglist = join(', ',
+      (qualify_with 'OLD', names_of @$oldlist),
+      (qualify_with 'NEW', names_of @$newlist),
+    );
+    $to = $to->name if blessed($to);
+    return strip tt q{
+      CREATE RULE _[% to %]_[% on %]_rule AS
+        ON [% on | upper %] TO [% to %]
+        DO INSTEAD (
+          SELECT [% to %]_[% on %]([% arglist %])
+        );
+    };
+  };
+}
+
+method root_table () {
+  $self->parent_source
+    ? $self->parent_source->root_table
+    : $self->schema->source($self->raw_source_name)
+}
+
+method view_definition () {
+  my $schema = $self->schema;
+  confess "Can't generate view without connected schema, sorry"
+    unless $schema && $schema->storage;
+  my $sqla = $schema->storage->sql_maker;
+  my $table = $self->schema->source($self->raw_source_name);
+  my $super_view = $self->parent_source;
+  my @all_parents = my @other_parents = @{$self->additional_parents||[]};
+  push(@all_parents, $super_view) if defined($super_view);
+  my @sources = ($table, @all_parents);
+  my @body_cols = map body_cols($_), @sources;
+  my @pk_cols = pk_cols $self;
+
+  # SELECT statement
+
+  my $am_root = !($super_view || @other_parents);
+
+  my $select = $sqla->select(
+    ($am_root
+      ? ($table->name)
+      : ([   # FROM _tbl _tbl
+           { $table->name => $table->name },
+           map {
+             my $parent = $_;
+             [ # JOIN view view
+               { $parent->name => $parent->name },
+               # ON _tbl.id = view.id
+               { map +(qualify_with($parent, $_), qualify_with($table, $_)),
+                   names_of @pk_cols }
+             ]
+           } @all_parents
+         ])
+      ),
+    [ (qualify_with $table, names_of @pk_cols), names_of @body_cols ],
+  ).';';
+
+  my ($now, @next) = grep defined, $super_view, $table, @other_parents;
+
+  # INSERT function
+
+  # NOTE: this assumes a single PK col called id with a sequence somewhere
+  # but nothing else -should- so fixing this should make everything work
+  my $insert_func =
+    function_body
+      $self->name.'_insert',
+      \@body_cols,
+      [
+        $sqla->insert( # INSERT INTO tbl/super_view (foo, ...) VALUES (_foo, ...)
+          $now->name,
+          { arg_hash $now },
+        ),
+        (map {
+          $sqla->insert( # INSERT INTO parent (id, ...)
+                         #   VALUES (currval('_root_tbl_id_seq'), ...)
+            $_->name,
+            {
+              (arg_hash $_),
+              id => \"currval('${\$self->root_table->name}_id_seq')",
+            }
+          )
+        } @next)
+      ];
+
+  # note - similar to arg_hash but not quite enough to share code sanely
+  my $pk_where = { # id = _id AND id2 = _id2 ...
+    map +($_ => \"= ${\argify $_}"), names_of @pk_cols
+  };
+
+  # UPDATE function
+
+  my $update_func =
+    function_body
+      $self->name.'_update',
+      [ @pk_cols, @body_cols ],
+      [ map $sqla->update(
+          $_->name, # UPDATE foo
+          { arg_hash $_ }, # SET a = _a
+          $pk_where,
+        ), @sources
+      ];
+
+  # DELETE function
+
+  my $delete_func =
+    function_body
+      $self->name.'_delete',
+      [ @pk_cols ],
+      [ map $sqla->delete($_->name, $pk_where), @sources ];
+
+  my @rules = (
+    (rule_body insert => $self, [], \@body_cols),
+    (rule_body update => $self, \@pk_cols, \@body_cols),
+    (rule_body delete => $self, \@pk_cols, []),
+  );
+  return join("\n\n", $select, $insert_func, $update_func, $delete_func, @rules);
+}
+
 1;