Ticket-5815: Per-view cache invalidation

django/utils/cache.py

@@ -23,6 +23,7 @@
 from django.core.cache import caches
 from django.http import HttpResponse, HttpResponseNotModified
 from django.utils.crypto import md5
+from django.utils.encoding import iri_to_uri
 from django.utils.http import http_date, parse_etags, parse_http_date_safe, quote_etag
 from django.utils.log import log_response
 from django.utils.regex_helper import _lazy_re_compile
@@ -333,20 +334,35 @@ def has_vary_header(response, header_query):
     return header_query.lower() in existing_headers
 
 
-def _i18n_cache_key_suffix(request, cache_key):
-    """If necessary, add the current locale or time zone to the cache key."""
+def _i18n_cache_key_suffix(request, cache_key:str) -> str:
+    """
+    If necessary, add the current locale or time zone to the cache key.
+    """
+    language_code = ""
+    timezone = ""
+
     if settings.USE_I18N:
         # first check if LocaleMiddleware or another middleware added
         # LANGUAGE_CODE to request, then fall back to the active language
         # which in turn can also fall back to settings.LANGUAGE_CODE
-        cache_key += ".%s" % getattr(request, "LANGUAGE_CODE", get_language())
+        language_code = getattr(request, "LANGUAGE_CODE", get_language())
     if settings.USE_TZ:
-        cache_key += ".%s" % get_current_timezone_name()
-    return cache_key
+        timezone = get_current_timezone_name()
+
+    return cache_key.handle_cache_key_suffixes(
+        cache_key=cache_key, language_code=language_code, timezone=timezone
+    )
+
+
+
 
 
 def _generate_cache_key(request, method, headerlist, key_prefix):
-    """Return a cache key from the headers given in the header list."""
+    """
+    Entry point for cache key generation.
+
+    Return a cache key from the headers given in the header list.
+    """
     ctx = md5(usedforsecurity=False)
     for header in headerlist:
         value = request.META.get(header)
@@ -359,19 +375,32 @@ def _generate_cache_key(request, method, headerlist, key_prefix):
         url.hexdigest(),
         ctx.hexdigest(),
     )
+
     return _i18n_cache_key_suffix(request, cache_key)
 
 
-def _generate_cache_header_key(key_prefix, request):
-    """Return a cache key for the header cache."""
-    url = md5(request.build_absolute_uri().encode("ascii"), usedforsecurity=False)
+def _generate_cache_key_from_request(*, key_prefix, request):
+    uri = _get_uri_from_request(request)
+    url_hash = md5(uri, usedforsecurity=False)
     cache_key = "views.decorators.cache.cache_header.%s.%s" % (
         key_prefix,
-        url.hexdigest(),
+        url_hash.hexdigest(),
     )
     return _i18n_cache_key_suffix(request, cache_key)
 
 
+def _generate_cache_key_from_uri(*, key_prefix, uri):
+
+    url_hash = md5(uri, usedforsecurity=False)
+    cache_key = "views.decorators.cache.cache_header.%s.%s" % (
+        key_prefix,
+        url_hash.hexdigest(),
+    )
+    return _i18n_cache_key_suffix(cache_key)
+
+
+
+
 def get_cache_key(request, key_prefix=None, method="GET", cache=None):
     """
     Return a cache key based on the request URL and query. It can be used
@@ -411,6 +440,8 @@ def learn_cache_key(request, response, cache_timeout=None, key_prefix=None, cach
         key_prefix = settings.CACHE_MIDDLEWARE_KEY_PREFIX
     if cache_timeout is None:
         cache_timeout = settings.CACHE_MIDDLEWARE_SECONDS
+
+    # Generate the cache key.
     cache_key = _generate_cache_header_key(key_prefix, request)
     if cache is None:
         cache = caches[settings.CACHE_MIDDLEWARE_ALIAS]
@@ -426,6 +457,8 @@ def learn_cache_key(request, response, cache_timeout=None, key_prefix=None, cach
             if header != "ACCEPT_LANGUAGE" or not is_accept_language_redundant:
                 headerlist.append("HTTP_" + header)
         headerlist.sort()
+
+        # Set the cache key.
         cache.set(cache_key, headerlist, cache_timeout)
         return _generate_cache_key(request, request.method, headerlist, key_prefix)
     else: