1 files changed, 56 insertions, 0 deletions
diff --git a/actioncable/lib/action_cable/server/configuration.rb b/actioncable/lib/action_cable/server/configuration.rb
new file mode 100644
index 0000000000..26209537df
--- /dev/null
+++ b/actioncable/lib/action_cable/server/configuration.rb
@@ -0,0 +1,56 @@
+# frozen_string_literal: true
+
+module ActionCable
+  module Server
+    # An instance of this configuration object is available via ActionCable.server.config, which allows you to tweak Action Cable configuration
+    # in a Rails config initializer.
+    class Configuration
+      attr_accessor :logger, :log_tags
+      attr_accessor :connection_class, :worker_pool_size
+      attr_accessor :disable_request_forgery_protection, :allowed_request_origins, :allow_same_origin_as_host
+      attr_accessor :cable, :url, :mount_path
+
+      def initialize
+        @log_tags = []
+
+        @connection_class = -> { ActionCable::Connection::Base }
+        @worker_pool_size = 4
+
+        @disable_request_forgery_protection = false
+        @allow_same_origin_as_host = true
+      end
+
+      # Returns constant of subscription adapter specified in config/cable.yml.
+      # If the adapter cannot be found, this will default to the Redis adapter.
+      # Also makes sure proper dependencies are required.
+      def pubsub_adapter
+        adapter = (cable.fetch("adapter") { "redis" })
+
+        # Require the adapter itself and give useful feedback about
+        #   1. Missing adapter gems and
+        #   2. Adapter gems' missing dependencies.
+        path_to_adapter = "action_cable/subscription_adapter/#{adapter}"
+        begin
+          require path_to_adapter
+        rescue LoadError => e
+          # We couldn't require the adapter itself. Raise an exception that
+          # points out config typos and missing gems.
+          if e.path == path_to_adapter
+            # We can assume that a non-builtin adapter was specified, so it's
+            # either misspelled or missing from Gemfile.
+            raise e.class, "Could not load the '#{adapter}' Action Cable pubsub adapter. Ensure that the adapter is spelled correctly in config/cable.yml and that you've added the necessary adapter gem to your Gemfile.", e.backtrace
+
+          # Bubbled up from the adapter require. Prefix the exception message
+          # with some guidance about how to address it and reraise.
+          else
+            raise e.class, "Error loading the '#{adapter}' Action Cable pubsub adapter. Missing a gem it depends on? #{e.message}", e.backtrace
+          end
+        end
+
+        adapter = adapter.camelize
+        adapter = "PostgreSQL" if adapter == "Postgresql"
+        "ActionCable::SubscriptionAdapter::#{adapter}".constantize
+      end
+    end
+  end
+end