lib/em-hiredis/base_client.rb
def configure(uri_string)
      uri = URI(uri_string)

      if uri.scheme == "unix"
        @host = uri.path
        @port = nil
      else
        @host = uri.host
        @port = uri.port
        @password = uri.password
        path = uri.path[1..-1]
        @db = path.to_i # Empty path => 0
      end
    end
def configure(uri_string)
      uri = URI(uri_string)

      if uri.scheme == "unix"
        @host = uri.path
        @port = nil
      else
        @host = uri.host
        @port = uri.port
        @password = uri.password
        path = uri.path[1..-1]
        @db = path.to_i # Empty path => 0
      end
    end
Configure the redis connection to use

 In usual operation, the uri should be passed to initialize. This method
 is useful for example when failing over to a slave connection at runtime