Add ActiveSupport::Notifications hook to Broadcaster#broadcast

This addition of this notification hook will give users better visibility
into the messages being sent over the PubSub adapter.

1 files changed, 49 insertions, 4 deletions

diff --git a/actioncable/test/server/broadcasting_test.rb b/actioncable/test/server/broadcasting_test.rb
index 3b4a7eaf90..ed377b7d5d 100644
--- a/actioncable/test/server/broadcasting_test.rb
+++ b/actioncable/test/server/broadcasting_test.rb
@@ -1,10 +1,7 @@
 require "test_helper"
+require "stubs/test_server"
 
 class BroadcastingTest < ActiveSupport::TestCase
-  class TestServer
-    include ActionCable::Server::Broadcasting
-  end
-
   test "fetching a broadcaster converts the broadcasting queue to a string" do
     broadcasting = :test_queue
     server = TestServer.new
@@ -12,4 +9,52 @@ class BroadcastingTest < ActiveSupport::TestCase
 
     assert_equal "test_queue", broadcaster.broadcasting
   end
+
+  test "broadcast generates notification" do
+    begin
+      server = TestServer.new
+
+      events = []
+      ActiveSupport::Notifications.subscribe "broadcast.action_cable" do |*args|
+        events << ActiveSupport::Notifications::Event.new(*args)
+      end
+
+      broadcasting = "test_queue"
+      message = { body: "test message" }
+      server.broadcast(broadcasting, message)
+
+      assert_equal 1, events.length
+      assert_equal "broadcast.action_cable", events[0].name
+      assert_equal broadcasting, events[0].payload[:broadcasting]
+      assert_equal message, events[0].payload[:message]
+      assert_equal ActiveSupport::JSON, events[0].payload[:coder]
+    ensure
+      ActiveSupport::Notifications.unsubscribe "broadcast.action_cable"
+    end
+  end
+
+  test "broadcaster from broadcaster_for generates notification" do
+    begin
+      server = TestServer.new
+
+      events = []
+      ActiveSupport::Notifications.subscribe "broadcast.action_cable" do |*args|
+        events << ActiveSupport::Notifications::Event.new(*args)
+      end
+
+      broadcasting = "test_queue"
+      message = { body: "test message" }
+
+      broadcaster = server.broadcaster_for(broadcasting)
+      broadcaster.broadcast(message)
+
+      assert_equal 1, events.length
+      assert_equal "broadcast.action_cable", events[0].name
+      assert_equal broadcasting, events[0].payload[:broadcasting]
+      assert_equal message, events[0].payload[:message]
+      assert_equal ActiveSupport::JSON, events[0].payload[:coder]
+    ensure
+      ActiveSupport::Notifications.unsubscribe "broadcast.action_cable"
+    end
+  end
 end