1 files changed, 35 insertions, 0 deletions
diff --git a/actioncable/lib/action_cable/channel/callbacks.rb b/actioncable/lib/action_cable/channel/callbacks.rb
new file mode 100644
index 0000000000..295d750e86
--- /dev/null
+++ b/actioncable/lib/action_cable/channel/callbacks.rb
@@ -0,0 +1,35 @@
+require 'active_support/callbacks'
+
+module ActionCable
+  module Channel
+    module Callbacks
+      extend  ActiveSupport::Concern
+      include ActiveSupport::Callbacks
+
+      included do
+        define_callbacks :subscribe
+        define_callbacks :unsubscribe
+      end
+
+      class_methods do
+        def before_subscribe(*methods, &block)
+          set_callback(:subscribe, :before, *methods, &block)
+        end
+
+        def after_subscribe(*methods, &block)
+          set_callback(:subscribe, :after, *methods, &block)
+        end
+        alias_method :on_subscribe, :after_subscribe
+
+        def before_unsubscribe(*methods, &block)
+          set_callback(:unsubscribe, :before, *methods, &block)
+        end
+
+        def after_unsubscribe(*methods, &block)
+          set_callback(:unsubscribe, :after, *methods, &block)
+        end
+        alias_method :on_unsubscribe, :after_unsubscribe
+      end
+    end
+  end
+end