django.middleware.cache

Cache middleware. If enabled, each Django-powered page will be cached based on URL. The canonical way to enable cache middleware is to set ``UpdateCacheMiddleware`` as your first piece of middleware, and ``FetchFromCacheMiddleware`` as the last:: MIDDLEWARE = [ 'django.middleware.cache.UpdateCacheMiddleware', ... 'django.middleware.cache.FetchFromCacheMiddleware' ] This is counter-intuitive, but correct: ``UpdateCacheMiddleware`` needs to run last during the response phase, which processes middleware bottom-up; ``FetchFromCacheMiddleware`` needs to run last during the request phase, which processes middleware top-down. The single-class ``CacheMiddleware`` can be used for some simple sites. However, if any other piece of middleware needs to affect the cache key, you'll need to use the two-part ``UpdateCacheMiddleware`` and ``FetchFromCacheMiddleware``. This'll most often happen when you're using Django's ``LocaleMiddleware``. More details about how the caching works: * Only GET or HEAD-requests with status code 200 are cached. * The number of seconds each page is stored for is set by the "max-age" section of the response's "Cache-Control" header, falling back to the CACHE_MIDDLEWARE_SECONDS setting if the section was not found. * This middleware expects that a HEAD request is answered with the same response headers exactly like the corresponding GET request. * When a hit occurs, a shallow copy of the original response object is returned from process_request. * Pages will be cached based on the contents of the request headers listed in the response's "Vary" header. * This middleware also sets ETag, Last-Modified, Expires and Cache-Control headers on the response object.