Disable referential integrity disabling in the test database, if a config param 'constraint_disabling' is set to false in the test section of database.yml, and pay attention to the order in which fixtures are defined when deleting and loading them.

1 files changed, 110 insertions, 0 deletions

diff --git a/lib/no_constraint_disabling.rb b/lib/no_constraint_disabling.rb
new file mode 100644
index 000000000..d515a959a
--- /dev/null
+++ b/lib/no_constraint_disabling.rb
@@ -0,0 +1,110 @@
+# In order to work around the problem of the database use not having
+# the permission to disable referential integrity when loading fixtures,
+# we redefine disable_referential_integrity so that it doesn't try to
+# disable foreign key constraints, and redefine the
+# ActiveRecord::Fixtures.create_fixtures method to pay attention to the order
+# which fixture tables are passed so that foreign key constraints won't be
+# violated. The only lines that are changed from the initial definition
+# are those between the "***" comments
+require 'active_record/fixtures'
+require 'active_record/connection_adapters/postgresql_adapter'
+module ActiveRecord
+  module ConnectionAdapters
+    class PostgreSQLAdapter < AbstractAdapter
+      def disable_referential_integrity(&block)
+       transaction {
+       yield
+        }
+      end
+    end
+  end
+end
+
+module ActiveRecord
+  class Fixtures
+
+    def self.create_fixtures(fixtures_directory, table_names, class_names = {})
+      table_names = [table_names].flatten.map { |n| n.to_s }
+      table_names.each { |n|
+        class_names[n.tr('/', '_').to_sym] = n.classify if n.include?('/')
+      }
+
+      # FIXME: Apparently JK uses this.
+      connection = block_given? ? yield : ActiveRecord::Base.connection
+
+      files_to_read = table_names.reject { |table_name|
+        fixture_is_cached?(connection, table_name)
+      }
+
+      unless files_to_read.empty?
+        connection.disable_referential_integrity do
+          fixtures_map = {}
+
+          fixture_files = files_to_read.map do |path|
+            table_name = path.tr '/', '_'
+
+            fixtures_map[path] = ActiveRecord::Fixtures.new(
+              connection,
+              table_name,
+              class_names[table_name.to_sym] || table_name.classify,
+              File.join(fixtures_directory, path))
+          end
+
+          all_loaded_fixtures.update(fixtures_map)
+
+          connection.transaction(:requires_new => true) do
+            # Patch - replace this...
+            # ***
+            # fixture_files.each do |ff|
+            #   conn = ff.model_class.respond_to?(:connection) ? ff.model_class.connection : connection
+            #   table_rows = ff.table_rows
+            #
+            #   table_rows.keys.each do |table|
+            #     conn.delete "DELETE FROM #{conn.quote_table_name(table)}", 'Fixture Delete'
+            #   end
+            #
+            #   table_rows.each do |table_name,rows|
+            #     rows.each do |row|
+            #       conn.insert_fixture(row, table_name)
+            #     end
+            #   end
+            # end
+            # ***
+            # ... with this
+            fixture_files.reverse.each do |ff|
+              conn = ff.model_class.respond_to?(:connection) ? ff.model_class.connection : connection
+              table_rows = ff.table_rows
+
+              table_rows.keys.each do |table|
+                conn.delete "DELETE FROM #{conn.quote_table_name(table)}", 'Fixture Delete'
+              end
+            end
+
+            fixture_files.each do |ff|
+              conn = ff.model_class.respond_to?(:connection) ? ff.model_class.connection : connection
+              table_rows = ff.table_rows
+              table_rows.each do |table_name,rows|
+                rows.each do |row|
+                  conn.insert_fixture(row, table_name)
+                end
+              end
+            end
+            # ***
+
+            # Cap primary key sequences to max(pk).
+            if connection.respond_to?(:reset_pk_sequence!)
+              table_names.each do |table_name|
+                connection.reset_pk_sequence!(table_name.tr('/', '_'))
+              end
+            end
+          end
+
+          cache_fixtures(connection, fixtures_map)
+        end
+      end
+      cached_fixtures(connection, table_names)
+    end
+
+  end
+
+end