module HTTPX::Plugins::Upgrade::InstanceMethods

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