Ticket #580: cachekey.diff

django/utils/cache.py

@@ +1 @@
+"this module contains helper methods for the caching stuff"
+
+import md5
+
+def get_cache_key(request):
+    """
+    This function returns a cache key based on a request. It takes
+    into account the URL and some HTTP headers and combines them
+    as a MD5 hexdigest to produce a key for the cache. Additionally
+    it prefixes it with some config values and constants.
+    """
+
+    accept_encoding = ''
+    if settings.CACHE_MIDDLEWARE_GZIP:
+        try:
+            accept_encoding = request.META['HTTP_ACCEPT_ENCODING']
+        except KeyError:
+            pass
+    accepts_gzip = 'gzip' in accept_encoding
+    request._cache_middleware_accepts_gzip = accepts_gzip
+
+    ctx = md5.new()
+    ctx.update(request.path)
+    ctx.update(str(accepts_gzip))
+    ctx.update(request.META.get('HTTP_COOKIE', ''))
+    ctx.update(request.META.get('HTTP_ACCEPT_LANGUAGE', ''))
+
+    cache_key = 'views.decorators.cache.cache_page.%s.%s' % \
+        (settings.CACHE_MIDDLEWARE_KEY_PREFIX, ctx.hexdigest())
+    return cache_key
+

django/middleware/cache.py

@@ -2 +2 @@
 from django.core.cache import cache
 from django.utils.httpwrappers import HttpResponseNotModified
 from django.utils.text import compress_string
+from django.utils.cache import get_cache_key
 import datetime, md5
 
 class CacheMiddleware:
@@ -31 +32 @@
             request._cache_middleware_set_cache = False
             return None # Don't bother checking the cache.
 
-        accept_encoding = ''
-        if settings.CACHE_MIDDLEWARE_GZIP:
-            try:
-                accept_encoding = request.META['HTTP_ACCEPT_ENCODING']
-            except KeyError:
-                pass
-        accepts_gzip = 'gzip' in accept_encoding
-        request._cache_middleware_accepts_gzip = accepts_gzip
-
         # This uses the same cache_key as views.decorators.cache.cache_page,
         # so the cache can be shared.
-        cache_key = 'views.decorators.cache.cache_page.%s.%s.%s' % \
-            (settings.CACHE_MIDDLEWARE_KEY_PREFIX, request.path, accepts_gzip)
+        cache_key = get_cache_key(request)
         request._cache_middleware_key = cache_key
 
         response = cache.get(cache_key, None)

django/views/decorators/cache.py

@@ -1 +1 @@
 from django.core.cache import cache
 from django.utils.httpwrappers import HttpResponseNotModified
 from django.utils.text import compress_string
+from django.utils.cache import get_cache_key
 import datetime, md5
 
 def cache_page(view_func, cache_timeout, key_prefix=''):
@@ -16 +17 @@
     unique across all Django instances on a particular server.
     """
     def _check_cache(request, *args, **kwargs):
-        try:
-            accept_encoding = request.META['HTTP_ACCEPT_ENCODING']
-        except KeyError:
-            accept_encoding = ''
-        accepts_gzip = 'gzip' in accept_encoding
-        cache_key = 'views.decorators.cache.cache_page.%s.%s.%s' % (key_prefix, request.path, accepts_gzip)
+        cache_key = get_cache_key(request)
         response = cache.get(cache_key, None)
         if response is None:
             response = view_func(request, *args, **kwargs)