add rough ActionDispatch adapter for testing Rails 3 APIs with Faraday

lib/faraday.rb

@@ -59,17 +59,19 @@ def all_loaded_constants
   module Adapter
     extend AutoloadHelper
     autoload_all 'faraday/adapter',
-      :NetHttp  => 'net_http',
-      :Typhoeus => 'typhoeus',
-      :Patron   => 'patron',
-      :Test     => 'test'
+      :ActionDispatch => 'action_dispatch',
+      :NetHttp        => 'net_http',
+      :Typhoeus       => 'typhoeus',
+      :Patron         => 'patron',
+      :Test           => 'test'
 
     register_lookup_modules \
-      :test     => :Test,
-      :net_http => :NetHttp,
-      :typhoeus => :Typhoeus,
-      :patron   => :Patron,
-      :net_http => :NetHttp
+      :action_dispatch => :ActionDispatch,
+      :test            => :Test,
+      :net_http        => :NetHttp,
+      :typhoeus        => :Typhoeus,
+      :patron          => :Patron,
+      :net_http        => :NetHttp
   end
 end
 

lib/faraday/adapter/action_dispatch.rb

@@ -0,0 +1,32 @@
+module Faraday
+  module Adapter
+    class ActionDispatch < Middleware
+      attr_reader :session
+
+      # Initializes a new middleware instance for each request.  Instead of 
+      # initiating an HTTP request with a web server, this adapter calls
+      # a Rails 3 app using integration tests.
+      #
+      # app     - The current Faraday request.
+      # session - An ActionDispatch::Integration::Session instance.
+      #
+      # Returns nothing.
+      def initialize(app, session)
+        super(app)
+        @session = session
+      end
+
+      def call(env)
+        process_body_for_request(env)
+        full_path = full_path_for(env[:url].path, env[:url].query, env[:url].fragment)
+        @session.__send__(env[:method], full_path, env[:body], env[:request_headers])
+        resp = @session.response
+        env.update \
+          :status           => resp.status,
+          :response_headers => resp.headers,
+          :body             => resp.body
+        @app.call env
+      end
+    end
+  end
+end