def keys(*a)
      if block_given?
        bucket.keys(*a) do |keys|
          # This API is currently inconsistent from protobuffs to http
          if keys.kind_of? Array
            keys.each do |key|
              yield key
            end
          else
            yield keys
          end
        end
      else
        bucket.keys(*a)
      end
    end
def keys(*a)
      if block_given?
        bucket.keys(*a) do |keys|
          # This API is currently inconsistent from protobuffs to http
          if keys.kind_of? Array
            keys.each do |key|
              yield key
            end
          else
            yield keys
          end
        end
      else
        bucket.keys(*a)
      end
    end
Iterate over all keys.