refactor channel look up to use a hash instead of an array and reduce the number of calls to safe_constantize because it can be slow

2 files changed, 3 insertions, 5 deletions

diff --git a/lib/action_cable/connection/subscriptions.rb b/lib/action_cable/connection/subscriptions.rb
index 0411d96413..69e3f60706 100644
--- a/lib/action_cable/connection/subscriptions.rb
+++ b/lib/action_cable/connection/subscriptions.rb
@@ -24,9 +24,7 @@ module ActionCable
         id_key = data['identifier']
         id_options = ActiveSupport::JSON.decode(id_key).with_indifferent_access
 
-        subscription_klass = connection.server.channel_classes.detect do |channel_class|
-          channel_class == id_options[:channel].safe_constantize
-        end
+        subscription_klass = connection.server.channel_classes[id_options[:channel]]
 
         if subscription_klass
           subscriptions[id_key] ||= subscription_klass.new(connection, id_key, id_options)
diff --git a/lib/action_cable/server/base.rb b/lib/action_cable/server/base.rb
index b09fbf6da4..43849928b9 100644
--- a/lib/action_cable/server/base.rb
+++ b/lib/action_cable/server/base.rb
@@ -36,11 +36,11 @@ module ActionCable
         @worker_pool ||= ActionCable::Server::Worker.pool(size: config.worker_pool_size)
       end
 
-      # Requires and returns an array of all the channel class constants in this application.
+      # Requires and returns an hash of all the channel class constants keyed by name.
       def channel_classes
         @channel_classes ||= begin
           config.channel_paths.each { |channel_path| require channel_path }
-          config.channel_class_names.collect { |name| name.constantize }
+          config.channel_class_names.each_with_object({}) { |name, hash| hash[name] = name.constantize }
         end
       end