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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.

é    )Úsettings)ÚDEFAULT_CACHE_ALIASÚcaches)Úget_cache_keyÚget_max_ageÚhas_vary_headerÚlearn_cache_keyÚpatch_response_headers)ÚMiddlewareMixinc               @   s*   e Zd ZdZd	dd„Zdd„ Zdd„ ZdS )
ÚUpdateCacheMiddlewarea6  
    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
    so that it'll get called last during the response phase.
    Nc             C   s.   t j| _t j| _t j| _t| j | _|| _	d S )N)
r   ÚCACHE_MIDDLEWARE_SECONDSÚcache_timeoutÚCACHE_MIDDLEWARE_KEY_PREFIXÚ
key_prefixÚCACHE_MIDDLEWARE_ALIASÚcache_aliasr   ÚcacheÚget_response)Úselfr   © r   ú[C:\Users\HIRONO~1\AppData\Local\Temp\pip-install-6bm3nxem\django\django\middleware\cache.pyÚ__init__@   s
    zUpdateCacheMiddleware.__init__c             C   s   t |dƒo|jS )NÚ_cache_update_cache)Úhasattrr   )r   ÚrequestÚresponser   r   r   Ú_should_update_cacheG   s    z*UpdateCacheMiddleware._should_update_cachec                sÐ   ˆ  ||¡s|S |js |jdkr$|S |js>|jr>t|dƒr>|S t|ƒ‰ˆdkrVˆj‰nˆdkrb|S t|ˆƒ ˆrÌ|jdkrÌt	||ˆˆj
ˆjd�‰ t|dƒr¼t|jƒr¼| ‡ ‡‡fdd	„¡ nˆj ˆ |ˆ¡ |S )
zSet the cache, if needed.)éÈ   i0  ÚCookieNr   r   )r   Úrenderc                s   ˆj  ˆ | ˆ¡S )N)r   Úset)Úr)Ú	cache_keyr   Útimeoutr   r   Ú<lambda>f   s    z8UpdateCacheMiddleware.process_response.<locals>.<lambda>)r   Z	streamingÚstatus_codeZCOOKIESÚcookiesr   r   r   r	   r   r   r   r   Úcallabler   Zadd_post_render_callbackr    )r   r   r   r   )r"   r   r#   r   Úprocess_responseJ   s&    
z&UpdateCacheMiddleware.process_response)N)Ú__name__Ú
__module__Ú__qualname__Ú__doc__r   r   r(   r   r   r   r   r   7   s   
r   c               @   s"   e Zd ZdZddd„Zdd„ ZdS )Ú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
    so that it'll get called last during the request phase.
    Nc             C   s&   t j| _t j| _t| j | _|| _d S )N)r   r   r   r   r   r   r   r   )r   r   r   r   r   r   u   s    z!FetchFromCacheMiddleware.__init__c             C   s”   |j dkrd|_dS t|| jd| jd�}|dkr:d|_dS | j |¡}|dkrx|j dkrxt|| jd| jd�}| j |¡}|dkrŠd|_dS d|_|S )zn
        Check whether the page is already cached and return the cached
        version if available.
        )ÚGETÚHEADFNr.   )r   Tr/   )Úmethodr   r   r   r   Úget)r   r   r"   r   r   r   r   Úprocess_request{   s     
z(FetchFromCacheMiddleware.process_request)N)r)   r*   r+   r,   r   r2   r   r   r   r   r-   m   s   
r-   c               @   s   e Zd ZdZddd„ZdS )ÚCacheMiddlewarezÌ
    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.
    Nc             K   sž   || _ y|d }|d krd}W n tk
r8   tj}Y nX || _y|d }|d krVt}W n tk
rr   tj}Y nX || _|d krˆtj}|| _	t
| j | _d S )Nr   Ú r   )r   ÚKeyErrorr   r   r   r   r   r   r   r   r   r   )r   r   r   Úkwargsr   r   r   r   r   r   Ÿ   s&    zCacheMiddleware.__init__)NN)r)   r*   r+   r,   r   r   r   r   r   r3   ˜   s   r3   N)r,   Zdjango.confr   Zdjango.core.cacher   r   Zdjango.utils.cacher   r   r   r   r	   Zdjango.utils.deprecationr
   r   r-   r3   r   r   r   r   Ú<module>,   s   6+