module HTTPX::Plugins::Upgrade::InstanceMethods

   # File lib/httpx/plugins/upgrade.rb
33 def fetch_response(request, selector, options)
34   response = super
35 
36   return unless response
37 
38   return response unless response.is_a?(Response)
39 
40   return response unless response.headers.key?("upgrade")
41 
42   upgrade_protocol = response.headers["upgrade"].split(/ *, */).first
43 
44   return response unless upgrade_protocol && options.upgrade_handlers.key?(upgrade_protocol)
45 
46   protocol_handler = options.upgrade_handlers[upgrade_protocol]
47 
48   return response unless protocol_handler
49 
50   log { "upgrading to #{upgrade_protocol}..." }
51   connection = find_connection(request.uri, selector, options)
52 
53   # do not upgrade already upgraded connections
54   return if connection.upgrade_protocol == upgrade_protocol
55 
56   protocol_handler.call(connection, request, response)
57 
58   # keep in the loop if the server is switching, unless
59   # the connection has been hijacked, in which case you want
60   # to terminante immediately
61   return fetch_response(request, selector, options) if response.status == 101 && !connection.hijacked
62 
63   response
64 end