Bug 377432: Fix "Building Schema object from database" to handle existing foreign keys

.gitignore

@@ -29,6 +29,7 @@
 /local
 .DS_Store
 .vscode/perl-lang
+.vagrant/
 version.json
 __lbheartbeat__
 .perl-version

Bugzilla/DB.pm

@@ -57,7 +57,7 @@ around 'attrs' => sub {
 # time we need a DBI handle to ensure the connection is alive.
 {
   my @DBI_METHODS = qw(
-    begin_work column_info commit do errstr get_info last_insert_id ping prepare
+    begin_work column_info commit do errstr foreign_key_info get_info last_insert_id ping prepare
     primary_key quote_identifier rollback selectall_arrayref selectall_hashref
     selectcol_arrayref selectrow_array selectrow_arrayref selectrow_hashref table_info
   );
@@ -765,10 +765,11 @@ sub bz_add_fks {
 
 sub bz_alter_column {
   my ($self, $table, $name, $new_def, $set_nulls_to) = @_;
-
   my $current_def = $self->bz_column_info($table, $name);
-
-  if (!$self->_bz_schema->columns_equal($current_def, $new_def)) {
+  if (!$current_def) {
+    $self->bz_add_column($table, $name, $new_def, $set_nulls_to);
+  }
+  elsif (!$self->_bz_schema->columns_equal($current_def, $new_def)) {
 
     # You can't change a column to be NOT NULL if you have no DEFAULT
     # and no value for $set_nulls_to, if there are any NULL values

Bugzilla/DB/Mysql.pm

@@ -1001,18 +1001,49 @@ sub _bz_raw_column_info {
   # DBD::mysql does not support selecting a specific column,
   # so we have to get all the columns on the table and find
   # the one we want.
-  my $info_sth = $self->column_info(undef, undef, $table, '%');
-
-  # Don't use fetchall_hashref as there's a Win32 DBI bug (292821)
-  my $col_data;
-  while ($col_data = $info_sth->fetchrow_hashref) {
-    last if $col_data->{'COLUMN_NAME'} eq $column;
+  my $info_cache = Bugzilla->request_cache->{'column_info_cache'}
+    || (Bugzilla->request_cache->{'column_info_cache'} = {});
+
+  if (!defined $info_cache->{$table}) {
+    # Don't use fetchall_hashref as there's a Win32 DBI bug (292821)
+    my $info_sth = $self->column_info(undef, undef, $table, '%');
+    while (my $col_data = $info_sth->fetchrow_hashref) {
+      if (!defined $info_cache->{$col_data->{'TABLE_NAME'}}) {
+        $info_cache->{$col_data->{'TABLE_NAME'}} = {};
+      }
+      $info_cache->{$col_data->{'TABLE_NAME'}}{$col_data->{'COLUMN_NAME'}} =
+        $col_data;
+    }
   }
 
-  if (!defined $col_data) {
-    return undef;
+  if (!defined Bugzilla->request_cache->{'column_fk_cache'}) {
+    my $fk_cache = Bugzilla->request_cache->{'column_fk_cache'} = {};
+    my $fk_sth = $self->foreign_key_info(undef, undef, undef, undef, undef,
+      undef);
+    while (my $fk = $fk_sth->fetchrow_hashref) {
+      next if !defined $fk->{'PKCOLUMN_NAME'};
+      if (!defined $fk_cache->{$fk->{'FKTABLE_NAME'}}) {
+        $fk_cache->{$fk->{'FKTABLE_NAME'}} = {};
+      }
+      $fk_cache->{$fk->{'FKTABLE_NAME'}}{$fk->{'FKCOLUMN_NAME'}} = $fk;
+    }
+  }
+  my $fk_cache = Bugzilla->request_cache->{'column_fk_cache'};
+
+  if (defined $info_cache->{$table}{$column}) {
+    my $col_data = $info_cache->{$table}{$column};
+    if (defined $fk_cache->{$table}{$column}) {
+      my $fk = $fk_cache->{$table}{$column};
+      $col_data->{'REFERENCES'} = {
+        TABLE   => $fk->{'PKTABLE_NAME'},
+        COLUMN  => $fk->{'PKCOLUMN_NAME'},
+        DELETE  => '',
+        created => 1,
+      };
+    }
+    return $col_data;
   }
-  return $col_data;
+  return undef;
 }
 
 =item C<bz_index_info_real($table, $index)>

Bugzilla/DB/Schema.pm

@@ -3025,11 +3025,12 @@ Sets the C<REFERENCES> item on the specified column.
 sub set_fk {
   my ($self, $table, $column, $fk_def) = @_;
 
-  # Don't want to modify the source def before we explicitly set it below.
-  # This is just us being extra-cautious.
-  my $column_def = dclone($self->get_column_abstract($table, $column));
+  my $column_def = $self->get_column_abstract($table, $column);
   die "Tried to set an fk on $table.$column, but that column doesn't exist"
     if !$column_def;
+  # Don't want to modify the source def before we explicitly set it below.
+  # This is just us being extra-cautious.
+  $column_def = dclone($column_def);
   if ($fk_def) {
     $column_def->{REFERENCES} = $fk_def;
   }

Bugzilla/DB/Schema/Mysql.pm

@@ -314,6 +314,9 @@ sub column_info_to_column {
   my $col_name = $column_info->{COLUMN_NAME};
 
   my $column = {};
+  if (defined $column_info->{REFERENCES}) {
+    $column->{REFERENCES} = $column_info->{REFERENCES};
+  }
 
   ($column->{NOTNULL} = 1) if $column_info->{NULLABLE} == 0;