Ticket #17834: etag.patch

django/utils/cache.py

@@ -94 +94 @@
             pass
 
 def _set_response_etag(response):
-    response['ETag'] = '"%s"' % hashlib.md5(response.content).hexdigest()
+    if response.content:
+        response['ETag'] = '"%s"' % hashlib.md5(response.content).hexdigest()
     return response
 
 def patch_response_headers(response, cache_timeout=None):

tests/regressiontests/cache/tests.py

@@ -18 +18 @@
 from django.core.cache.backends.base import (CacheKeyWarning,
     InvalidCacheBackendError)
 from django.db import router
-from django.http import HttpResponse, HttpRequest, QueryDict
+from django.http import HttpResponse, HttpRequest, QueryDict, HttpResponseRedirect
 from django.middleware.cache import (FetchFromCacheMiddleware,
     UpdateCacheMiddleware, CacheMiddleware)
 from django.template import Template
@@ -1739 +1739 @@
         self.assertFalse(response.has_header('ETag'))
         response = response.render()
         self.assertTrue(response.has_header('ETag'))
+        # Response with empty body should not be given implicit ETag
+        response = HttpResponseRedirect('/')
+        patch_response_headers(response)
+        self.assertFalse(response.has_header('ETag'))
 
 TestWithTemplateResponse = override_settings(
         CACHE_MIDDLEWARE_KEY_PREFIX='settingsprefix',