Do not cache new resources in HttpCacheResponder

lib/responders/flash_responder.rb

@@ -88,7 +88,7 @@ def initialize(controller, resources, options={})
     def to_html
       super
 
-      unless !respond_to?(:"to_#{format}") || get? || @flash == false
+      if set_i18n_flash?
         if has_errors?
           controller.flash[:alert] ||= @alert if @alert
           status = Responders::FlashResponder.flash_keys.last
@@ -107,6 +107,10 @@ def to_html
 
   protected
 
+    def set_i18n_flash? #:nodoc:
+      !get? && @flash != false
+    end
+
     def mount_i18n_options(status) #:nodoc:
       resource_name = if resource.class.respond_to?(:human_name)
         resource.class.human_name

lib/responders/http_cache_responder.rb

@@ -15,9 +15,9 @@ def initialize(controller, resources, options={})
     end
 
     def to_format
-      if get? && @http_cache != false && controller.response.last_modified.nil?
+      if do_http_cache?
         timestamp = resources.flatten.map do |resource|
-          resource.updated_at.utc if resource.respond_to?(:updated_at)
+          (resource.updated_at || Time.now).utc if resource.respond_to?(:updated_at)
         end.compact.max
 
         controller.response.last_modified = timestamp if timestamp
@@ -29,5 +29,15 @@ def to_format
 
       super
     end
+
+  protected
+
+    def do_http_cache?
+      get? && @http_cache != false && !new_record? && controller.response.last_modified.nil?
+    end
+
+    def new_record?
+      resource.respond_to?(:new_record?) && resource.new_record?
+    end
   end
 end

test/http_cache_responder_test.rb

@@ -17,6 +17,12 @@ def collection
     respond_with [Model.new(Time.utc(2009)), Model.new(Time.utc(2008))]
   end
 
+  def new_record
+    model = Model.new(Time.utc(2009))
+    model.new_record = true
+    respond_with(model)
+  end
+
   def empty
     respond_with []
   end
@@ -101,4 +107,16 @@ def test_work_with_an_empty_array
     assert_match /xml/, @response.body
     assert_equal 200, @response.status
   end
+
+  def test_it_does_not_set_body_etag
+    get :collection
+    assert_nil @response.headers["ETag"]
+  end
+
+  def test_does_not_set_cache_for_new_records
+    get :new_record
+    assert_nil @response.headers["Last-Modified"]
+    assert_equal "<xml />", @response.body
+    assert_equal 200, @response.status
+  end
 end

test/test_helper.rb

@@ -43,6 +43,12 @@ class ApplicationController < ActionController::Base
 end
 
 class Model < Struct.new(:updated_at)
+  attr_writer :new_record
+
+  def new_record?
+    @new_record || false
+  end
+
   def to_xml(*args)
     "<xml />"
   end