Make toolbar compatible with FORCE_SCRIPT_NAME

Previously, if a project used the `FORCE_SCRIPT_NAME` setting (common when
hosting a Django application on a subdirectory path via a reverse proxy),
the `django.urls.resolve()` call would always raise `Resolver404` in the
middleware. As a result, `is_toolbar_request()` always returned False.

This caused internal toolbar URLs to be inspected, and also indirectly
led to a request loop when refreshing the history panel.

In most cases (if `FORCE_SCRIPT_NAME` is unset), `get_script_prefix()` will
return "/" and the `replace()` will be a no-op.

Author: dmartin

debug_toolbar/toolbar.py

@@ -13,7 +13,7 @@
 from django.dispatch import Signal
 from django.template import TemplateSyntaxError
 from django.template.loader import render_to_string
-from django.urls import include, path, re_path, resolve
+from django.urls import get_script_prefix, include, path, re_path, resolve
 from django.urls.exceptions import Resolver404
 from django.utils.module_loading import import_string
 from django.utils.translation import get_language, override as lang_override
@@ -165,7 +165,8 @@ def is_toolbar_request(cls, request):
         # not have resolver_match set.
         try:
             resolver_match = request.resolver_match or resolve(
-                request.path, getattr(request, "urlconf", None)
+                request.path.replace(get_script_prefix(), "/", 1),
+                getattr(request, "urlconf", None),
             )
         except Resolver404:
             return False

docs/changes.rst

@@ -4,6 +4,9 @@ Change log
 Pending
 -------
 
+* Fixed internal toolbar requests being instrumented if the Django setting
+  ``FORCE_SCRIPT_NAME`` was set.
+
 4.4.6 (2024-07-10)
 ------------------
 

tests/test_integration.py

@@ -244,6 +244,23 @@ def test_is_toolbar_request_override_request_urlconf(self):
         self.request.path = "/__debug__/render_panel/"
         self.assertTrue(self.toolbar.is_toolbar_request(self.request))
 
+    @patch("debug_toolbar.toolbar.get_script_prefix", return_value="/path/")
+    def test_is_toolbar_request_with_script_prefix(self, mocked_get_script_prefix):
+        """
+        Test cases when Django is running under a path prefix, such as via the
+        FORCE_SCRIPT_NAME setting.
+        """
+        self.request.path = "/path/__debug__/render_panel/"
+        self.assertTrue(self.toolbar.is_toolbar_request(self.request))
+
+        self.request.path = "/path/invalid/__debug__/render_panel/"
+        self.assertFalse(self.toolbar.is_toolbar_request(self.request))
+
+        self.request.path = "/path/render_panel/"
+        self.assertFalse(self.toolbar.is_toolbar_request(self.request))
+
+        self.assertEqual(mocked_get_script_prefix.call_count, 3)
+
     def test_data_gone(self):
         response = self.client.get(
             "/__debug__/render_panel/?store_id=GONE&panel_id=RequestPanel"