1 files changed, 14 insertions, 7 deletions
diff --git a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
index 66c7852f6e..a9c0949950 100644
--- a/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
+++ b/actioncable/lib/action_cable/subscription_adapter/postgresql.rb
@@ -1,6 +1,9 @@
-gem 'pg', '~> 0.18'
-require 'pg'
-require 'thread'
+# frozen_string_literal: true
+
+gem "pg", "~> 0.18"
+require "pg"
+require "thread"
+require "digest/sha1"
 
 module ActionCable
   module SubscriptionAdapter
@@ -12,16 +15,16 @@ module ActionCable
 
       def broadcast(channel, payload)
         with_connection do |pg_conn|
-          pg_conn.exec("NOTIFY #{pg_conn.escape_identifier(channel)}, '#{pg_conn.escape_string(payload)}'")
+          pg_conn.exec("NOTIFY #{pg_conn.escape_identifier(channel_identifier(channel))}, '#{pg_conn.escape_string(payload)}'")
         end
       end
 
       def subscribe(channel, callback, success_callback = nil)
-        listener.add_subscriber(channel, callback, success_callback)
+        listener.add_subscriber(channel_identifier(channel), callback, success_callback)
       end
 
       def unsubscribe(channel, callback)
-        listener.remove_subscriber(channel, callback)
+        listener.remove_subscriber(channel_identifier(channel), callback)
       end
 
       def shutdown
@@ -33,7 +36,7 @@ module ActionCable
           pg_conn = ar_conn.raw_connection
 
           unless pg_conn.is_a?(PG::Connection)
-            raise 'ActiveRecord database must be Postgres in order to use the Postgres ActionCable storage adapter'
+            raise "The Active Record database must be PostgreSQL in order to use the PostgreSQL Action Cable storage adapter"
           end
 
           yield pg_conn
@@ -41,6 +44,10 @@ module ActionCable
       end
 
       private
+        def channel_identifier(channel)
+          channel.size > 63 ? Digest::SHA1.hexdigest(channel) : channel
+        end
+
         def listener
           @listener || @server.mutex.synchronize { @listener ||= Listener.new(self, @server.event_loop) }
         end