Merge pull request #6609 from readthedocs/handle-infinite-redirect-404

Raise exception when we get an InfiniteRedirect

readthedocs/proxito/views/mixins.py

@@ -14,6 +14,8 @@
 from django.utils.encoding import iri_to_uri
 from django.views.static import serve
 
+from readthedocs.redirects.exceptions import InfiniteRedirectException
+
 log = logging.getLogger(__name__)  # noqa
 
 
@@ -167,7 +169,7 @@ def get_redirect_response(self, request, redirect_path, proxito_path, http_statu
                 'Infinite Redirect: FROM URL is the same than TO URL. url=%s',
                 new_path,
             )
-            return HttpResponse('Infinite Redirect.', status=404)
+            raise InfiniteRedirectException()
 
         if http_status and http_status == 301:
             return HttpResponsePermanentRedirect(new_path)

readthedocs/proxito/views/serve.py

@@ -19,6 +19,7 @@
 from readthedocs.core.utils.extend import SettingsOverrideObject
 from readthedocs.projects import constants
 from readthedocs.projects.templatetags.projects_tags import sort_version_aware
+from readthedocs.redirects.exceptions import InfiniteRedirectException
 
 from .mixins import ServeDocsMixin, ServeRedirectMixin
 
@@ -243,7 +244,11 @@ def get(self, request, proxito_path, template_name='404.html'):
             full_path=proxito_path,
         )
         if redirect_path and http_status:
-            return self.get_redirect_response(request, redirect_path, proxito_path, http_status)
+            try:
+                return self.get_redirect_response(request, redirect_path, proxito_path, http_status)
+            except InfiniteRedirectException:
+                # Continue with our normal 404 handling in this case
+                pass
 
         # If that doesn't work, attempt to serve the 404 of the current version (version_slug)
         # Secondly, try to serve the 404 page for the default version

readthedocs/redirects/exceptions.py

@@ -0,0 +1,4 @@
+class InfiniteRedirectException(Exception):
+    """
+    Exception raised when a redirect loops forever
+    """