def ferret_index
      ensure_index_exists
      (@ferret_index ||= Ferret::Index::Index.new(index_definition[:ferret])).tap do |idx|
        idx.batch_size = index_definition[:reindex_batch_size]
        idx.logger = logger
      end
    end
def ferret_index
      ensure_index_exists
      (@ferret_index ||= Ferret::Index::Index.new(index_definition[:ferret])).tap do |idx|
        idx.batch_size = index_definition[:reindex_batch_size]
        idx.logger = logger
      end
    end
The 'real' Ferret Index instance