Merge pull request #32 from jer-k/rejection

Add handler for rejections from ActionCable

Author: NullVoxPopuli

README.md

@@ -37,6 +37,7 @@ The available hooks to tie in to are:
  - `disconnected {}`
  - `connected {}`
  - `subscribed {}`
+ - `rejected {}`
  - `errored { |msg| }`
  - `received { |msg }`
  - `pinged { |msg| }`

lib/action_cable_client.rb

@@ -23,7 +23,7 @@ class Commands
   # The queue should store entries in the format:
   # [ action, data ]
   attr_accessor :message_queue, :_subscribed
-  attr_accessor :_subscribed_callback, :_pinged_callback, :_connected_callback, :_disconnected_callback
+  attr_accessor :_subscribed_callback, :_rejected_callback, :_pinged_callback, :_connected_callback, :_disconnected_callback
 
   def_delegator :_websocket_client, :onerror, :errored
   def_delegator :_websocket_client, :send, :send_msg
@@ -109,6 +109,19 @@ def connected
     end
   end
 
+  # callback when the server rejects the subscription
+  #
+  # @example
+  #   client = ActionCableClient.new(uri, 'RoomChannel')
+  #   client.rejected do
+  #     # do things after the server rejects the subscription
+  #   end
+  def rejected
+    self._rejected_callback = proc do |json|
+      yield(json)
+    end
+  end
+
   # callback when the client receives a confirm_subscription message
   # from the action_cable server.
   # This is only called once, and signifies that you can now send
@@ -162,6 +175,8 @@ def handle_received_message(message)
     elsif is_welcome?(json)
       subscribe
       _connected_callback&.call(json)
+    elsif is_rejection?(json)
+      _rejected_callback&.call(json)
     elsif !subscribed?
       check_for_subscribe_confirmation(json)
     else
@@ -174,7 +189,7 @@ def handle_received_message(message)
   # {"identifier" => "_ping","type" => "confirm_subscription"}
   def check_for_subscribe_confirmation(message)
     message_type = message[Message::TYPE_KEY]
-    return unless  Message::TYPE_CONFIRM_SUBSCRIPTION == message_type
+    return unless Message::TYPE_CONFIRM_SUBSCRIPTION == message_type
 
     self._subscribed = true
     _subscribed_callback&.call
@@ -193,6 +208,11 @@ def is_welcome?(message)
     Message::IDENTIFIER_WELCOME == message_identifier
   end
 
+  def is_rejection?(message)
+    message_type = message[Message::TYPE_KEY]
+    Message::TYPE_REJECT_SUBSCRIPTION == message_type
+  end
+
   def subscribe
     msg = _message_factory.create(Commands::SUBSCRIBE)
     send_msg(msg.to_json)

lib/action_cable_client/message.rb

@@ -9,6 +9,7 @@ class Message
     # TODO: find a better place for this constant
     TYPE_KEY = 'type'
     TYPE_CONFIRM_SUBSCRIPTION = 'confirm_subscription'
+    TYPE_REJECT_SUBSCRIPTION = 'reject_subscription'
 
     attr_reader :_command, :_identifier, :_data
 

spec/unit/action_cable_client_spec.rb

@@ -89,6 +89,23 @@
         end
       end
 
+      context 'is a rejection' do
+        let(:hash) { { 'type' => 'reject_subscription' } }
+        let(:message) { hash.to_json }
+
+        it 'calls _rejected_callback' do
+          result = nil
+
+          @client.rejected do |data|
+            result = data
+          end
+
+          @client.send(:handle_received_message, message)
+
+          expect(result).to eq(hash)
+        end
+      end
+
       context 'empty messages are ignored' do
         let(:message) { '' }