Use ActiveSupport::Callbacks for Channel subscription callbacks.

 * Rely on AS::Callbacks for callback handling.
 * Add before_subscribe, after_subscribe, before_unsubscribe and
   after_unsubscribe convenience methods
 * alias on_subscribe and on_unsubscribe to after_subscribe and
   after_unsubscribe, respectively.
 * Remove `subscribed` and `unsubscribed` from the callback chain:
   these methods are now executed as the subject of the callbacks.
 * Update portions of ActionCable to use the more specific
   callback names.

1 files changed, 6 insertions, 13 deletions

diff --git a/lib/action_cable/channel/base.rb b/lib/action_cable/channel/base.rb
index 2f1b4a187d..171558e371 100644
--- a/lib/action_cable/channel/base.rb
+++ b/lib/action_cable/channel/base.rb
@@ -71,9 +71,6 @@ module ActionCable
       include Naming
       include Broadcasting
 
-      on_subscribe   :subscribed
-      on_unsubscribe :unsubscribed
-
       attr_reader :params, :connection
       delegate :logger, to: :connection
 
@@ -138,7 +135,9 @@ module ActionCable
       # Called by the cable connection when its cut so the channel has a chance to cleanup with callbacks.
       # This method is not intended to be called directly by the user. Instead, overwrite the #unsubscribed callback.
       def unsubscribe_from_channel
-        run_unsubscribe_callbacks
+        run_callbacks :unsubscribe do
+          unsubscribed
+        end
         logger.info "#{self.class.name} unsubscribed"
       end
 
@@ -176,7 +175,9 @@ module ActionCable
 
         def subscribe_to_channel
           logger.info "#{self.class.name} subscribing"
-          run_subscribe_callbacks
+          run_callbacks :subscribe do
+            subscribed
+          end
         end
 
 
@@ -205,14 +206,6 @@ module ActionCable
             end
           end
         end
-
-        def run_subscribe_callbacks
-          self.class.on_subscribe_callbacks.each { |callback| send(callback) }
-        end
-
-        def run_unsubscribe_callbacks
-          self.class.on_unsubscribe_callbacks.each { |callback| send(callback) }
-        end
     end
   end
 end