Remove lang cookie for mobile app requests. (#22731)

* Remove lang cookie for mobile app requests.

Responses for mobile app requests must not include language preference cookie.

PROD-1107

openedx/core/djangoapps/lang_pref/middleware.py

@@ -70,14 +70,13 @@ class LanguagePreferenceMiddleware(object):
                     pass
 
             # If set, set the user_pref in the LANGUAGE_COOKIE
-            if user_pref:
-                if not is_request_from_mobile_app(request):
-                    response.set_cookie(
-                        settings.LANGUAGE_COOKIE,
-                        value=user_pref,
-                        domain=settings.SESSION_COOKIE_DOMAIN,
-                        max_age=COOKIE_DURATION,
-                    )
+            if user_pref and not is_request_from_mobile_app(request):
+                response.set_cookie(
+                    settings.LANGUAGE_COOKIE,
+                    value=user_pref,
+                    domain=settings.SESSION_COOKIE_DOMAIN,
+                    max_age=COOKIE_DURATION,
+                )
             else:
                 response.delete_cookie(
                     settings.LANGUAGE_COOKIE,

openedx/core/djangoapps/lang_pref/tests/test_middleware.py

@@ -257,18 +257,18 @@ class TestUserPreferenceMiddleware(CacheIsolationTestCase):
 
     @mock.patch('openedx.core.djangoapps.lang_pref.middleware.is_request_from_mobile_app')
     @mock.patch('openedx.core.djangoapps.lang_pref.middleware.get_user_preference')
-    def test_lang_pref_cookie_must_not_sent_to_mobile(self, mock_get_user_preference, mock_is_mobile_request):
+    def test_remove_lang_cookie_for_mobile_app(self, mock_get_user_preference, mock_is_mobile_request):
         """
-        Test to verify language preference cookie must not be set for mobile requests
+        Test to verify language preference cookie removed for mobile app requests.
         """
-        mock_get_user_preference.return_value = 'test_value'
-        mock_is_mobile_request.return_value = True
+        mock_get_user_preference.return_value = 'en'
+        mock_is_mobile_request.return_value = False
+        response = mock.Mock(spec=HttpResponse)
 
-        response = self.client.get('/')
-        self.middleware.process_response(self.request, response)
-        self.assertFalse(response.cookies.get('openedx-language-preference'))
+        response = self.middleware.process_response(self.request, response)
+        response.delete_cookie.assert_not_called()
+        response.set_cookie.assert_called()
 
-        mock_is_mobile_request.return_value = False
-        response = self.client.get('/')
-        self.middleware.process_response(self.request, response)
-        self.assertTrue(response.cookies.get('openedx-language-preference'))
+        mock_is_mobile_request.return_value = True
+        response = self.middleware.process_response(self.request, response)
+        response.delete_cookie.assert_called()