Cache

Cache#

class trytond.cache.Cache(name[, duration[, context[, context_ignored_keys]]])#

Use to cache values between server requests.

The name should be unique and it’s used to identify the cache. Usually <class_name>.<content_name> is used to make it unique.

The duration parameter defines how long a cached value stays valid but if it is not set the value remains valid until it is cleared.

And the context parameter is used to indicate if the cache depends on the user context and is True by default. Keys specified in context_ignored_keys are ignored.

The cache is cleaned on Transaction starts and resets on Transaction commit or rollback.

Warning

As there is no deepcopy of the values cached, they must never be mutated after being set in or retrieved from the cache.

Cache.size_limit#

The maximal number of values cached. The value comes from the entry with the same name under the cache section of the configuration using the default entry as default value.

Cache.hit#

Count the number of times the cache returned a cached value.

Cache.miss#

Count the number of times the cache did not contain the key.

classmethod Cache.stats()#

Yield statistics for each instance.

Cache.get(key[, default])#

Retrieve the value of the key in the cache.

If a default is specified it is returned when the key is missing otherwise it returns None.

Cache.set(key, value)#

Set the value of the key in the cache.

Cache.clear()#

Clear all the keys in the cache.

classmethod Cache.clear_all()#

Clear all cache instances.

classmethod Cache.sync(transaction)#

Synchronize caches between servers using transaction instance.

Cache.sync_since(value)#

Return True if the last synchronization was done before value.

classmethod Cache.commit(transaction)#

Apply cache changes from transaction.

classmethod Cache.rollback(transaction)#

Remove cache changes from transaction.

classmethod Cache.drop(dbname)#

Drop all caches for named database.

Note

By default Tryton uses a MemoryCache, but this behaviour can be overridden by setting a fully qualified name of an alternative class defined in the class of the cache section.

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