Cache backends¶
The cache backends is used to store references to already created thumbnails in order to
avoid unnecessary disk or network usage. The Thumbnail
object is cached and will be returned
directly in get_thumbnail
if the cache returns it.
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class
thumbnails.cache_backends.
BaseCacheBackend
[source]¶ Extendible cache backend that should be used when creating a new cache backend. Subclasses should only override methods prefixed with
_
.-
_get
(thumbnail_name)[source]¶ Backend specific handling of get, should be overridden by subclasses.
Parameters: thumbnail_name – String or list with the name/hash of the thumbnail. Return type: Thumbnail
-
_set
(thumbnail_name, thumbnail)[source]¶ Backend specific handling of set, should be overridden by subclasses.
Parameters: - thumbnail_name – String with the name of the thumbnail.
- thumbnail – The Thumbnail object that should be cached.
-
-
class
thumbnails.cache_backends.
SimpleCacheBackend
[source]¶ Cache backend that stores objects in a dict on the backend instance.
-
class
thumbnails.cache_backends.
RedisCacheBackend
[source]¶ Cache backend that connects to Redis with redis-py. It uses the
THUMBNAIL_CACHE_CONNECTION_URI
setting as connection configuration. The setting should contain a string on the form:redis://host:port/db
, example:redis://127.0.0.1:6379/0
will give the default settings. This backend does not sett time-to-live on the cached items, thus they will be in redis until they are deleted.If the settings string is not good enough for your configuration, it is possible to extend this backend and override
get_settings
.-
get_settings
()[source]¶ This creates a dict with keyword arguments used to create the redis client. It is used like
redis.StrictClient(**self.get_settings())
. Thus, if the settings string is not enough to generate the wanted setting you can override this function.Returns: A dict with keyword arguments for the redis client constructor.
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