Fixed #17734 -- Made sure to only redirect translated URLs if they can actually be resolved to prevent unwanted redirects. Many thanks to Orne Brocaar and Anssi Kääriäinen for input.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17621 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/middleware/locale.py

@@ -1,10 +1,13 @@
 "This is the locale selecting middleware that will look at accept headers"
 
-from django.core.urlresolvers import get_resolver, LocaleRegexURLResolver
+from django.conf import settings
+from django.core.urlresolvers import (is_valid_path, get_resolver,
+                                      LocaleRegexURLResolver)
 from django.http import HttpResponseRedirect
 from django.utils.cache import patch_vary_headers
 from django.utils import translation
 
+
 class LocaleMiddleware(object):
     """
     This is a very simple middleware that parses a request
@@ -23,13 +26,17 @@ class LocaleMiddleware(object):
 
     def process_response(self, request, response):
         language = translation.get_language()
-        translation.deactivate()
-
         if (response.status_code == 404 and
                 not translation.get_language_from_path(request.path_info)
                     and self.is_language_prefix_patterns_used()):
-            return HttpResponseRedirect(
-                '/%s%s' % (language, request.get_full_path()))
+            urlconf = getattr(request, 'urlconf', None)
+            language_path = '/%s%s' % (language, request.path_info)
+            if settings.APPEND_SLASH and not language_path.endswith('/'):
+                language_path = language_path + '/'
+            if is_valid_path(language_path, urlconf):
+                return HttpResponseRedirect(
+                    '/%s%s' % (language, request.get_full_path()))
+        translation.deactivate()
 
         patch_vary_headers(response, ('Accept-Language',))
         if 'Content-Language' not in response: