Check IF_NONE_MATCH header for directory listings

lib/remote_storage/swift.rb

@@ -75,9 +75,10 @@ module RemoteStorage
     end
 
     def get_directory_listing(user, directory)
-      # TODO check IF_NONE_MATCH header
       etag = redis.hget "rs_meta:#{user}:#{directory}/", "etag"
 
+      none_match = (server.env["HTTP_IF_NONE_MATCH"] || "").split(",").map(&:strip)
+      server.halt 304 if none_match.include? etag
 
       server.headers["Content-Type"] = "application/json"
       server.headers["ETag"] = %Q("#{etag}")

spec/swift/app_spec.rb

@@ -183,6 +183,13 @@ describe "App" do
           last_response.headers["ETag"].must_equal "\"bla\""
         end
 
+        it "responds with 304 when IF_NONE_MATCH header contains the ETag" do
+          header "If-None-Match", "bla"
+          get "/phil/food/"
+
+          last_response.status.must_equal 304
+        end
+
         it "contains all items in the directory" do
           get "/phil/food/"