lib/anycable/rails/refinements/subscriptions.rb in anycable-rails-1.0.0.preview2 vs lib/anycable/rails/refinements/subscriptions.rb in anycable-rails-1.0.0.rc1

@@ -5,9 +5,14 @@
     module Subscriptions # :nodoc:
       refine ActionCable::Connection::Subscriptions do
         # Find or add a subscription to the list
         def fetch(identifier)
           add("identifier" => identifier) unless subscriptions[identifier]
+
+          unless subscriptions[identifier]
+            raise "Channel not found: #{ActiveSupport::JSON.decode(identifier).fetch("channel")}"
+          end
+
           subscriptions[identifier]
         end
       end
     end
   end