# File lib/openstack/connection.rb, line 187
    def req(method, path, options = {})
      server   = options[:server]   || @service_host
      port     = options[:port]     || @service_port
      scheme   = options[:scheme]   || @service_scheme
      headers  = options[:headers]  || {'content-type' => 'application/json'}
      data     = options[:data]
      attempts = options[:attempts] || 0
      path = @service_path + path
      res = csreq(method,server,path,port,scheme,headers,data,attempts)
      res.code.match(/^20.$/) ? (return res) : OpenStack::Exception.raise_exception(res)
    end