def query_key(path)
      i = 0
      path.map do |v|
        i += 1
        if i != 1
          "[#{v}]"
        else
          v
        end
      end.join('')
    end
def query_key(path)
      i = 0
      path.map do |v|
        i += 1
        if i != 1
          "[#{v}]"
        else
          v
        end
      end.join('')
    end
Generate the key for a nested param attribute