1 files changed, 36 insertions, 0 deletions
diff --git a/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/cascade.rb b/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/cascade.rb
new file mode 100644
index 0000000000..a038aa1105
--- /dev/null
+++ b/actionpack/lib/action_dispatch/vendor/rack-1.1.pre/rack/cascade.rb
@@ -0,0 +1,36 @@
+module Rack
+  # Rack::Cascade tries an request on several apps, and returns the
+  # first response that is not 404 (or in a list of configurable
+  # status codes).
+
+  class Cascade
+    attr_reader :apps
+
+    def initialize(apps, catch=404)
+      @apps = apps
+      @catch = [*catch]
+    end
+
+    def call(env)
+      status = headers = body = nil
+      raise ArgumentError, "empty cascade"  if @apps.empty?
+      @apps.each { |app|
+        begin
+          status, headers, body = app.call(env)
+          break  unless @catch.include?(status.to_i)
+        end
+      }
+      [status, headers, body]
+    end
+
+    def add app
+      @apps << app
+    end
+
+    def include? app
+      @apps.include? app
+    end
+
+    alias_method :<<, :add
+  end
+end