1 files changed, 45 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb b/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb
new file mode 100644
index 0000000000..62542bdb22
--- /dev/null
+++ b/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+require "rack/body_proxy"
+require "rack/utils"
+
+module ActiveSupport
+  module Cache
+    module Strategy
+      module LocalCache
+        #--
+        # This class wraps up local storage for middlewares. Only the middleware method should
+        # construct them.
+        class Middleware # :nodoc:
+          attr_reader :name, :local_cache_key
+
+          def initialize(name, local_cache_key)
+            @name = name
+            @local_cache_key = local_cache_key
+            @app = nil
+          end
+
+          def new(app)
+            @app = app
+            self
+          end
+
+          def call(env)
+            LocalCacheRegistry.set_cache_for(local_cache_key, LocalStore.new)
+            response = @app.call(env)
+            response[2] = ::Rack::BodyProxy.new(response[2]) do
+              LocalCacheRegistry.set_cache_for(local_cache_key, nil)
+            end
+            cleanup_on_body_close = true
+            response
+          rescue Rack::Utils::InvalidParameterError
+            [400, {}, []]
+          ensure
+            LocalCacheRegistry.set_cache_for(local_cache_key, nil) unless
+              cleanup_on_body_close
+          end
+        end
+      end
+    end
+  end
+end