Use .httpdate for expires date formatting

Specified in RFC 7231, section 7.1.1.2: Date.

2 files changed, 6 insertions, 30 deletions

diff --git a/lib/rack/utils.rb b/lib/rack/utils.rb
index c253f3cf..eb49466d 100644
--- a/lib/rack/utils.rb
+++ b/lib/rack/utils.rb
@@ -221,31 +221,7 @@ module Rack
         domain  = "; domain=#{value[:domain]}"   if value[:domain]
         path    = "; path=#{value[:path]}"       if value[:path]
         max_age = "; max-age=#{value[:max_age]}" if value[:max_age]
-        # There is an RFC mess in the area of date formatting for Cookies. Not
-        # only are there contradicting RFCs and examples within RFC text, but
-        # there are also numerous conflicting names of fields and partially
-        # cross-applicable specifications.
-        #
-        # These are best described in RFC 2616 3.3.1. This RFC text also
-        # specifies that RFC 822 as updated by RFC 1123 is preferred. That is a
-        # fixed length format with space-date delimited fields.
-        #
-        # See also RFC 1123 section 5.2.14.
-        #
-        # RFC 6265 also specifies "sane-cookie-date" as RFC 1123 date, defined
-        # in RFC 2616 3.3.1. RFC 6265 also gives examples that clearly denote
-        # the space delimited format. These formats are compliant with RFC 2822.
-        #
-        # For reference, all involved RFCs are:
-        # RFC 822
-        # RFC 1123
-        # RFC 2109
-        # RFC 2616
-        # RFC 2822
-        # RFC 2965
-        # RFC 6265
-        expires = "; expires=" +
-          rfc2822(value[:expires].clone.gmtime) if value[:expires]
+        expires = "; expires=#{value[:expires].httpdate}" if value[:expires]
         secure = "; secure"  if value[:secure]
         httponly = "; HttpOnly" if (value.key?(:httponly) ? value[:httponly] : value[:http_only])
         same_site =
diff --git a/test/spec_response.rb b/test/spec_response.rb
index 987199de..4fd7d2b3 100644
--- a/test/spec_response.rb
+++ b/test/spec_response.rb
@@ -186,7 +186,7 @@ describe Rack::Response do
     response.delete_cookie "foo"
     response["Set-Cookie"].must_equal [
       "foo2=bar2",
-      "foo=; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"
+      "foo=; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 GMT"
     ].join("\n")
   end
 
@@ -196,10 +196,10 @@ describe Rack::Response do
     response.set_cookie "foo", {:value => "bar", :domain => ".example.com"}
     response["Set-Cookie"].must_equal ["foo=bar; domain=sample.example.com", "foo=bar; domain=.example.com"].join("\n")
     response.delete_cookie "foo", :domain => ".example.com"
-    response["Set-Cookie"].must_equal ["foo=bar; domain=sample.example.com", "foo=; domain=.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"].join("\n")
+    response["Set-Cookie"].must_equal ["foo=bar; domain=sample.example.com", "foo=; domain=.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 GMT"].join("\n")
     response.delete_cookie "foo", :domain => "sample.example.com"
-    response["Set-Cookie"].must_equal ["foo=; domain=.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000",
-                                         "foo=; domain=sample.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"].join("\n")
+    response["Set-Cookie"].must_equal ["foo=; domain=.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 GMT",
+                                         "foo=; domain=sample.example.com; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 GMT"].join("\n")
   end
 
   it "can delete cookies with the same name with different paths" do
@@ -211,7 +211,7 @@ describe Rack::Response do
 
     response.delete_cookie "foo", :path => "/path"
     response["Set-Cookie"].must_equal ["foo=bar; path=/",
-                                         "foo=; path=/path; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 -0000"].join("\n")
+                                         "foo=; path=/path; max-age=0; expires=Thu, 01 Jan 1970 00:00:00 GMT"].join("\n")
   end
 
   it "can do redirects" do