aboutsummaryrefslogtreecommitdiffstats
path: root/actioncable/lib/action_cable/connection/client_socket.rb
blob: 2b45befb01bd529e46af9056b19f6a6757b4a506 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
# frozen_string_literal: true
require "websocket/driver"

module ActionCable
  module Connection
    #--
    # This class is heavily based on faye-websocket-ruby
    #
    # Copyright (c) 2010-2015 James Coglan
    class ClientSocket # :nodoc:
      def self.determine_url(env)
        scheme = secure_request?(env) ? "wss:" : "ws:"
        "#{ scheme }//#{ env['HTTP_HOST'] }#{ env['REQUEST_URI'] }"
      end

      def self.secure_request?(env)
        return true if env["HTTPS"] == "on"
        return true if env["HTTP_X_FORWARDED_SSL"] == "on"
        return true if env["HTTP_X_FORWARDED_SCHEME"] == "https"
        return true if env["HTTP_X_FORWARDED_PROTO"] == "https"
        return true if env["rack.url_scheme"] == "https"

        return false
      end

      CONNECTING = 0
      OPEN       = 1
      CLOSING    = 2
      CLOSED     = 3

      attr_reader :env, :url

      def initialize(env, event_target, event_loop, protocols)
        @env          = env
        @event_target = event_target
        @event_loop   = event_loop

        @url = ClientSocket.determine_url(@env)

        @driver = @driver_started = nil
        @close_params = ["", 1006]

        @ready_state = CONNECTING

        # The driver calls +env+, +url+, and +write+
        @driver = ::WebSocket::Driver.rack(self, protocols: protocols)

        @driver.on(:open)    { |e| open }
        @driver.on(:message) { |e| receive_message(e.data) }
        @driver.on(:close)   { |e| begin_close(e.reason, e.code) }
        @driver.on(:error)   { |e| emit_error(e.message) }

        @stream = ActionCable::Connection::Stream.new(@event_loop, self)
      end

      def start_driver
        return if @driver.nil? || @driver_started
        @stream.hijack_rack_socket

        if callback = @env["async.callback"]
          callback.call([101, {}, @stream])
        end

        @driver_started = true
        @driver.start
      end

      def rack_response
        start_driver
        [ -1, {}, [] ]
      end

      def write(data)
        @stream.write(data)
      rescue => e
        emit_error e.message
      end

      def transmit(message)
        return false if @ready_state > OPEN
        case message
        when Numeric then @driver.text(message.to_s)
        when String  then @driver.text(message)
        when Array   then @driver.binary(message)
          else false
        end
      end

      def close(code = nil, reason = nil)
        code   ||= 1000
        reason ||= ""

        unless code == 1000 || (code >= 3000 && code <= 4999)
          raise ArgumentError, "Failed to execute 'close' on WebSocket: " \
                               "The code must be either 1000, or between 3000 and 4999. " \
                               "#{code} is neither."
        end

        @ready_state = CLOSING unless @ready_state == CLOSED
        @driver.close(reason, code)
      end

      def parse(data)
        @driver.parse(data)
      end

      def client_gone
        finalize_close
      end

      def alive?
        @ready_state == OPEN
      end

      def protocol
        @driver.protocol
      end

      private
        def open
          return unless @ready_state == CONNECTING
          @ready_state = OPEN

          @event_target.on_open
        end

        def receive_message(data)
          return unless @ready_state == OPEN

          @event_target.on_message(data)
        end

        def emit_error(message)
          return if @ready_state >= CLOSING

          @event_target.on_error(message)
        end

        def begin_close(reason, code)
          return if @ready_state == CLOSED
          @ready_state = CLOSING
          @close_params = [reason, code]

          @stream.shutdown if @stream
          finalize_close
        end

        def finalize_close
          return if @ready_state == CLOSED
          @ready_state = CLOSED

          @event_target.on_close(*@close_params)
        end
    end
  end
end