_V@sdZddlmZddlmZmZddlmZmZm Z m Z m Z Gddde Z Gddde ZGd d d e eZd S) a 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_CLASSES = [ '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. )settings)DEFAULT_CACHE_ALIAScaches) get_cache_key get_max_agehas_vary_headerlearn_cache_keypatch_response_headersc@s:eZdZdZddZddZddZdS) UpdateCacheMiddlewarea> Response-phase cache middleware that updates the cache if the response is cacheable. Must be used as part of the two-part update/fetch cache middleware. UpdateCacheMiddleware must be the first piece of middleware in MIDDLEWARE_CLASSES so that it'll get called last during the response phase. cCs8tj|_tj|_tj|_t|j|_dS)N) rCACHE_MIDDLEWARE_SECONDS cache_timeoutCACHE_MIDDLEWARE_KEY_PREFIX key_prefixCACHE_MIDDLEWARE_ALIAS cache_aliasrcache)selfr9/tmp/pip-build-ghmbqnp_/Django/django/middleware/cache.py__init__?s   zUpdateCacheMiddleware.__init__cCst|do|jS)N_cache_update_cache)hasattrr)rrequestresponserrr_should_update_cacheEsz*UpdateCacheMiddleware._should_update_cachecsj||s|S|js.|jdkr2|S|j rX|jrXt|drX|St|dkr|jndkr|St|rt ||j dj t |drt |jr|jfddqj j|n|S) zSets the cache, if needed.CookieNrrrendercsjj|S)N)rset)r) cache_keyrtimeoutrrdsz8UpdateCacheMiddleware.process_response..)rZ streaming status_codeZCOOKIEScookiesrrr r rrrrcallablerZadd_post_render_callbackr)rrrr)r rr!rprocess_responseHs&"     !z&UpdateCacheMiddleware.process_responseN)__name__ __module__ __qualname____doc__rrr&rrrrr 6s   r c@s.eZdZdZddZddZdS)FetchFromCacheMiddlewarea) Request-phase cache middleware that fetches a page from the cache. Must be used as part of the two-part update/fetch cache middleware. FetchFromCacheMiddleware must be the last piece of middleware in MIDDLEWARE_CLASSES so that it'll get called last during the request phase. cCs,tj|_tj|_t|j|_dS)N)rr rrrrr)rrrrrss  z!FetchFromCacheMiddleware.__init__cCs|jdkrd|_dSt||jdd|j}|dkrSd|_dS|jj|}|dkr|jdkrt||jdd|j}|jj|}n|dkrd|_dSd|_|S)zp Checks whether the page is already cached and returns the cached version if available. GETHEADFNrT)zGETzHEAD)methodrrrrget)rrr rrrrprocess_requestxs       z(FetchFromCacheMiddleware.process_requestN)r'r(r)r*rr0rrrrr+ks  r+c@s%eZdZdZdddZdS)CacheMiddlewarez Cache middleware that provides basic behavior for many simple sites. Also used as the hook point for the cache decorator, which is generated using the decorator-from-middleware utility. NcKsy#|d}|dkr"d}nWntk r@tj}YnX||_y#|d}|dkrlt}nWntk rtj}YnX||_|dkrtj}n||_t |j|_ dS)Nrr) KeyErrorrr rrrrr r rr)rr kwargsrrrrrrs$             zCacheMiddleware.__init__)r'r(r)r*rrrrrr1s r1N)r*Z django.confrZdjango.core.cacherrZdjango.utils.cacherrrrr objectr r+r1rrrr,s (5*