Cache descriptors for Python and Zope
Project description
Method cache
Memoize with timeout
Memoize with timeout caches methods with a certain timeout:
>>> import math >>> import gocept.cache.method >>> >>> class Point(object): ... ... def __init__(self, x, y): ... self.x, self.y = x, y ... ... @gocept.cache.method.Memoize(0.1) ... def distance(self, x, y): ... print 'computing distance' ... return math.sqrt((self.x - x)**2 + (self.y - y)**2) ... >>> point = Point(1.0, 2.0)
When we first ask for the distance it is computed:
>>> point.distance(2, 2) computing distance 1.0
The second time the distance is not computed but returned from the cache:
>>> point.distance(2, 2) 1.0
Now, let’s wait 0.1 secondes, the value we set as cache timeout. After that the distance is computed again:
>>> import time >>> time.sleep(0.5) >>> point.distance(2, 2) computing distance 1.0
Cached Properties
Transaction Bound Cache
The transaction bound cache is invalidated on transaction boundaries.
Create a class and set some data:
>>> import gocept.cache.property
>>> class Foo(object):
...
... cache = gocept.cache.property.TransactionBoundCache('_cache', dict)
...
>>> foo = Foo()
>>> foo.cache
{}
>>> foo.cache['A'] = 1
>>> foo.cache
{'A': 1}
If we commit the transaction the cache is empty again:
>>> import transaction
>>> transaction.commit()
>>> foo.cache
{}
The same happens on abort – once we get a ZODB supporting it:
#>>> foo.cache[‘A’] = 1 #>>> foo.cache #{‘A’: 1} #>>> transaction.abort() #>>> foo.cache #{}
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
