- def delete_with_history(user)
- if self.visible
- if WayNode.find(:first, :joins => "INNER JOIN current_ways ON current_ways.id = current_way_nodes.id", :conditions => [ "current_ways.visible = 1 AND current_way_nodes.node_id = ?", self.id ])
- raise OSM::APIPreconditionFailedError.new
- elsif RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id", :conditions => [ "visible = 1 AND member_type='node' and member_id=?", self.id])
- raise OSM::APIPreconditionFailedError.new
+ # need to start the transaction here, so that the database can
+ # provide repeatable reads for the used-by checks. this means it
+ # shouldn't be possible to get race conditions.
+ Node.transaction do
+ check_consistency(self, new_node, user)
+ if WayNode.find(:first, :joins => "INNER JOIN current_ways ON current_ways.id = current_way_nodes.id", :conditions => [ "current_ways.visible = ? AND current_way_nodes.node_id = ?", true, self.id ])
+ raise OSM::APIPreconditionFailedError.new
+ elsif RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id", :conditions => [ "visible = ? AND member_type='Node' and member_id=? ", true, self.id])
+ raise OSM::APIPreconditionFailedError.new