feat: Add custom attribute for cookie header size

openedx/core/lib/request_utils.py

@@ -23,9 +23,9 @@
 # .. toggle_name: request_utils.capture_cookie_sizes
 # .. toggle_implementation: WaffleFlag
 # .. toggle_default: False
-# .. toggle_description: Enables capturing of cookie sizes for monitoring purposes. This can be useful for tracking
-#       down large cookies and avoiding hitting limits on the total size of cookies. See the CookieMonitoringMiddleware
-#       docstring for details on the monitoring custom attributes that will be set.
+# .. toggle_description: Enables more detailed capturing of cookie sizes for monitoring purposes. This can be useful for tracking
+#       down large cookies if requests are nearing limits on the total size of cookies. See the
+#       CookieMonitoringMiddleware docstring for details on the monitoring custom attributes that will be set.
 # .. toggle_warnings: Enabling this flag will add a number of custom attributes, and could adversely affect other
 #       monitoring. Only enable temporarily, or lower TOP_N_COOKIES_CAPTURED and TOP_N_COOKIE_GROUPS_CAPTURED django
 #       settings to capture less data.
@@ -123,6 +123,10 @@ def process_request(self, request):
 
         Attributes that are added by this middleware:
 
+        cookies.header.size: The total size in bytes of the cookie header
+
+        If CAPTURE_COOKIE_SIZES is enabled, additional attributes will be added:
+
         cookies.<N>.name: The name of the Nth largest cookie
         cookies.<N>.size: The size of the Nth largest cookie
         cookies..group.<N>.name: The name of the Nth largest cookie.
@@ -141,6 +145,10 @@ def process_request(self, request):
         - TOP_N_COOKIE_GROUPS_CAPTURED
 
         """
+
+        raw_header_cookie = request.META.get('HTTP_COOKIE', '')
+        set_custom_attribute('cookies.header.size', len(raw_header_cookie.encode('utf-8')))
+
         if not CAPTURE_COOKIE_SIZES.is_enabled():
             return
 

openedx/core/lib/tests/test_request_utils.py

@@ -97,15 +97,32 @@ def assertCourseIdFieldsMatch(self, course_id, org, course, run):
         assert course_id.course == course
         assert course_id.run == run
 
+    @patch("openedx.core.lib.request_utils.CAPTURE_COOKIE_SIZES")
+    @patch("openedx.core.lib.request_utils.set_custom_attribute")
+    def test_basic_cookie_monitoring(self, mock_set_custom_attribute, mock_capture_cookie_sizes):
+        mock_capture_cookie_sizes.is_enabled.return_value = False
+        middleware = CookieMonitoringMiddleware()
+
+        cookies_dict = {'a': 'b'}
+
+        factory = RequestFactory()
+        for name, value in cookies_dict.items():
+            factory.cookies[name] = value
+
+        mock_request = factory.request()
+
+        middleware.process_request(mock_request)
+
+        mock_set_custom_attribute.assert_called_once_with('cookies.header.size', 3)
+
     @patch("openedx.core.lib.request_utils.CAPTURE_COOKIE_SIZES")
     @patch("openedx.core.lib.request_utils.set_custom_attribute")
     def test_cookie_monitoring(self, mock_set_custom_attribute, mock_capture_cookie_sizes):
 
         mock_capture_cookie_sizes.is_enabled.return_value = True
         middleware = CookieMonitoringMiddleware()
 
-        mock_request = Mock()
-        mock_request.COOKIES = {
+        cookies_dict = {
             "a": "." * 100,
             "_b": "." * 13,
             "_c_": "." * 13,
@@ -117,6 +134,12 @@ def test_cookie_monitoring(self, mock_set_custom_attribute, mock_capture_cookie_
             "d": "." * 3,
         }
 
+        factory = RequestFactory()
+        for name, value in cookies_dict.items():
+            factory.cookies[name] = value
+
+        mock_request = factory.request()
+
         middleware.process_request(mock_request)
 
         mock_set_custom_attribute.assert_has_calls([
@@ -147,6 +170,7 @@ def test_cookie_monitoring(self, mock_set_custom_attribute, mock_capture_cookie_
             call('cookies_total_size', 192),
             call('cookies_unaccounted_size', 3),
             call('cookies_total_num', 9),
+            call('cookies.header.size', 238)
         ], any_order=True)
 
     @patch("openedx.core.lib.request_utils.CAPTURE_COOKIE_SIZES")
@@ -156,13 +180,18 @@ def test_cookie_monitoring_max_group(self, mock_set_custom_attribute, mock_captu
         mock_capture_cookie_sizes.is_enabled.return_value = True
         middleware = CookieMonitoringMiddleware()
 
-        mock_request = Mock()
-        mock_request.COOKIES = {
+        cookies_dict = {
             "a": "." * 10,
             "b_a": "." * 15,
             "b_c": "." * 20,
         }
 
+        factory = RequestFactory()
+        for name, value in cookies_dict.items():
+            factory.cookies[name] = value
+
+        mock_request = factory.request()
+
         middleware.process_request(mock_request)
 
         mock_set_custom_attribute.assert_has_calls([
@@ -188,12 +217,20 @@ def test_cookie_monitoring_no_cookies(self, mock_set_custom_attribute, mock_capt
         mock_capture_cookie_sizes.is_enabled.return_value = True
         middleware = CookieMonitoringMiddleware()
 
-        mock_request = Mock()
-        mock_request.COOKIES = {}
+        cookies_dict = {}
+
+        factory = RequestFactory()
+        for name, value in cookies_dict.items():
+            factory.cookies[name] = value
+
+        mock_request = factory.request()
 
         middleware.process_request(mock_request)
 
-        mock_set_custom_attribute.assert_has_calls([call('cookies_total_size', 0)], any_order=True)
+        mock_set_custom_attribute.assert_has_calls([
+            call('cookies_total_size', 0),
+            call('cookies.header.size', 0)
+        ], any_order=True)
 
     @patch("openedx.core.lib.request_utils.CAPTURE_COOKIE_SIZES")
     @patch("openedx.core.lib.request_utils.set_custom_attribute")
@@ -202,12 +239,17 @@ def test_cookie_monitoring_no_groups(self, mock_set_custom_attribute, mock_captu
         mock_capture_cookie_sizes.is_enabled.return_value = True
         middleware = CookieMonitoringMiddleware()
 
-        mock_request = Mock()
-        mock_request.COOKIES = {
+        cookies_dict = {
             "a": "." * 10,
             "b": "." * 15,
         }
 
+        factory = RequestFactory()
+        for name, value in cookies_dict.items():
+            factory.cookies[name] = value
+
+        mock_request = factory.request()
+
         middleware.process_request(mock_request)
 
         mock_set_custom_attribute.assert_has_calls([