Check exclude before flagging cookies as secure in ActionDispatch::SSL (#32262)

* Check exclude before flagging cookies as secure.

* Update comments in ActionDispatch::SSL.

[Catherine Khuu + Rafael Mendonça França]

actionpack/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Check exclude before flagging cookies as secure.
+ 
+    *Catherine Khuu*
+
 *   Rails 6 requires Ruby 2.4.1 or newer.
 
     *Jeremy Daer*

actionpack/lib/action_dispatch/middleware/ssl.rb

@@ -15,6 +15,8 @@ module ActionDispatch
   #
   #      config.ssl_options = { redirect: { exclude: -> request { request.path =~ /healthcheck/ } } }
   #
+  #    Cookies will not be flagged as secure for excluded requests.
+  #
   # 2. <b>Secure cookies</b>: Sets the +secure+ flag on cookies to tell browsers they
   #    must not be sent along with +http://+ requests. Enabled by default. Set
   #    +config.ssl_options+ with <tt>secure_cookies: false</tt> to disable this feature.
@@ -71,7 +73,7 @@ def call(env)
       if request.ssl?
         @app.call(env).tap do |status, headers, body|
           set_hsts_header! headers
-          flag_cookies_as_secure! headers if @secure_cookies
+          flag_cookies_as_secure! headers if @secure_cookies && !@exclude.call(request)
         end
       else
         return redirect_to_https request unless @exclude.call(request)

actionpack/test/dispatch/ssl_test.rb

@@ -208,6 +208,14 @@ def test_cookies_as_not_secure_with_secure_cookies_disabled
     assert_cookies(*DEFAULT.split("\n"))
   end
 
+  def test_cookies_as_not_secure_with_exclude
+    excluding = { exclude: -> request { request.domain =~ /example/ } }
+    get headers: { "Set-Cookie" => DEFAULT }, ssl_options: { redirect: excluding }
+
+    assert_cookies(*DEFAULT.split("\n"))
+    assert_response :ok
+  end
+
   def test_no_cookies
     get
     assert_nil response.headers["Set-Cookie"]