fsl.utils.cache

This module provides the Cache class., a simple in-memory cache.

exception fsl.utils.cache.Expired

Bases: Exception

Exception raised by the Cache.get() metho when an attempt is made to access a cache item that has expired.

class fsl.utils.cache.CacheItem(key, value, expiry=0)

Bases: object

Internal container class used to store Cache items.

class fsl.utils.cache.Cache(maxsize=100)

Bases: object

The Cache is a simple in-memory cache built on a collections.OrderedDict. The Cache class has the following features:

• When an item is added to a full cache, the oldest entry is automatically dropped.
• Expiration times can be specified for individual items. If a request is made to access an expired item, an Expired exception is raised.

put(key, value, expiry=0)

Put an item in the cache.

Parameters:

• key – Item identifier (must be hashable).
• value – The item to store.
• expiry – Expiry time in seconds. An item with an expiry time of 0 will not expire.

get(key, *args, **kwargs)

Get an item from the cache.

Parameters:

• key – Item identifier.
• default – Default value to return if the item is not in the cache, or has expired.

clear()

Remove all items from the cache.