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diff --git a/actioncable/lib/action_cable/server/broadcasting.rb b/actioncable/lib/action_cable/server/broadcasting.rb
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+++ b/actioncable/lib/action_cable/server/broadcasting.rb
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+# frozen_string_literal: true
+
+module ActionCable
+  module Server
+    # Broadcasting is how other parts of your application can send messages to a channel's subscribers. As explained in Channel, most of the time, these
+    # broadcastings are streamed directly to the clients subscribed to the named broadcasting. Let's explain with a full-stack example:
+    #
+    #   class WebNotificationsChannel < ApplicationCable::Channel
+    #     def subscribed
+    #       stream_from "web_notifications_#{current_user.id}"
+    #     end
+    #   end
+    #
+    #   # Somewhere in your app this is called, perhaps from a NewCommentJob:
+    #   ActionCable.server.broadcast \
+    #     "web_notifications_1", { title: "New things!", body: "All that's fit for print" }
+    #
+    #   # Client-side CoffeeScript, which assumes you've already requested the right to send web notifications:
+    #   App.cable.subscriptions.create "WebNotificationsChannel",
+    #     received: (data) ->
+    #       new Notification data['title'], body: data['body']
+    module Broadcasting
+      # Broadcast a hash directly to a named <tt>broadcasting</tt>. This will later be JSON encoded.
+      def broadcast(broadcasting, message, coder: ActiveSupport::JSON)
+        broadcaster_for(broadcasting, coder: coder).broadcast(message)
+      end
+
+      # Returns a broadcaster for a named <tt>broadcasting</tt> that can be reused. Useful when you have an object that
+      # may need multiple spots to transmit to a specific broadcasting over and over.
+      def broadcaster_for(broadcasting, coder: ActiveSupport::JSON)
+        Broadcaster.new(self, String(broadcasting), coder: coder)
+      end
+
+      private
+        class Broadcaster
+          attr_reader :server, :broadcasting, :coder
+
+          def initialize(server, broadcasting, coder:)
+            @server, @broadcasting, @coder = server, broadcasting, coder
+          end
+
+          def broadcast(message)
+            server.logger.debug "[ActionCable] Broadcasting to #{broadcasting}: #{message.inspect}"
+
+            payload = { broadcasting: broadcasting, message: message, coder: coder }
+            ActiveSupport::Notifications.instrument("broadcast.action_cable", payload) do
+              encoded = coder ? coder.encode(message) : message
+              server.pubsub.broadcast broadcasting, encoded
+            end
+          end
+        end
+    end
+  end
+end