1 files changed, 21 insertions, 0 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/load_interlock.rb b/actionpack/lib/action_dispatch/middleware/load_interlock.rb
new file mode 100644
index 0000000000..07f498319c
--- /dev/null
+++ b/actionpack/lib/action_dispatch/middleware/load_interlock.rb
@@ -0,0 +1,21 @@
+require 'active_support/dependencies'
+require 'rack/body_proxy'
+
+module ActionDispatch
+  class LoadInterlock
+    def initialize(app)
+      @app = app
+    end
+
+    def call(env)
+      interlock = ActiveSupport::Dependencies.interlock
+      interlock.start_running
+      response = @app.call(env)
+      body = Rack::BodyProxy.new(response[2]) { interlock.done_running }
+      response[2] = body
+      response
+    ensure
+      interlock.done_running unless body
+    end
+  end
+end