# File estraierpure.rb, line 756
    def uri_to_id(uri)
      Utility::check_types({ uri=>String }) if $DEBUG
      @status = -1
      return -1 unless @url
      turl = @url + "/uri_to_id"
      reqheads = [ "Content-Type: application/x-www-form-urlencoded" ]
      reqheads.push("Authorization: Basic " + Utility::base_encode(@auth)) if @auth
      reqbody = "uri=" + CGI::escape(uri)
      resbody = StringIO::new
      rv = Utility::shuttle_url(turl, @pxhost, @pxport, @timeout, reqheads, reqbody, nil, resbody)
      @status = rv
      return nil if rv != 200
      resbody.string.chomp
    end