diff options
Diffstat (limited to 'django')
| -rw-r--r-- | django/middleware/cache.py | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/django/middleware/cache.py b/django/middleware/cache.py index 0fdffe1bbe..196b1995ff 100644 --- a/django/middleware/cache.py +++ b/django/middleware/cache.py @@ -43,6 +43,8 @@ More details about how the caching works: """ +import time + from django.conf import settings from django.core.cache import DEFAULT_CACHE_ALIAS, caches from django.utils.cache import ( @@ -53,6 +55,7 @@ from django.utils.cache import ( patch_response_headers, ) from django.utils.deprecation import MiddlewareMixin +from django.utils.http import parse_http_date_safe class UpdateCacheMiddleware(MiddlewareMixin): @@ -171,6 +174,15 @@ class FetchFromCacheMiddleware(MiddlewareMixin): request._cache_update_cache = True return None # No cache information available, need to rebuild. + # Derive the age estimation of the cached response. + if (max_age_seconds := get_max_age(response)) is not None and ( + expires_timestamp := parse_http_date_safe(response["Expires"]) + ) is not None: + now_timestamp = int(time.time()) + remaining_seconds = expires_timestamp - now_timestamp + # Use Age: 0 if local clock got turned back. + response["Age"] = max(0, max_age_seconds - remaining_seconds) + # hit, return cached response request._cache_update_cache = False return response |