Tools and config for memcache related caching
This package combines the features from lovely.memcached and plone.memoize.ram. It provides a decorator and utility for Memcaches at EEA. The decorator allows you set dependencies known by eea.cache
Note
This add-on doesn't do anything by itself. It needs to be integrated by a developer within your own products. For reference you can check the eea.app.visualization package.
Contents
Add eea.cache to your eggs and zcml section in your buildout and re-run buildout:
eggs = ... eea.cache zcml = ... eea.cache eea.cache-overrides
You can download a sample buildout from https://github.com/eea/eea.cache/tree/master/buildouts/plone4
Install eea.cache within Site Setup > Add-ons
Start memcache:
$ bin/memcached start
>>> def key(method, self): ... return method.__name__ >>> from eea.cache import cache >>> @cache(key, dependencies=["frontpage"]) ... def myMethod(num): ... return num*num
Lets clear any running memcache:
>>> from eea.cache.event import InvalidateMemCacheEvent >>> from zope.event import notify >>> notify(InvalidateMemCacheEvent(raw=True, dependencies=['frontpage']))
Our myMethod will now be cached with the key returned from the method 'key' and with dependency 'frontpage':
>>> myMethod(2) 4 >>> myMethod(3) 4 >>> notify(InvalidateMemCacheEvent(raw=True, dependencies=['frontpage'])) >>> myMethod(3) 9
By default your content is cached in memcache for one hour (3600 seconds). You can change this by adding an int property within: ZMI > portal_properties > site_properties called memcached_defaultLifetime and set it's value to 86400 (one day) for example.
Starting with eea.cache 5.1 you can also pass a lifetime key with the duration in seconds which will override the defaultLifetime either given from the portal property or the default one from lovely.memcached of 3600 seconds:
ex: in order to cache the result only for 4 minutes >>> @cache(key, dependencies=["frontpage"], lifetime=240) ... def myMethod(num): ... return num*num
If you use cache decorator for BrowserView methods or directly on Zope objects methods cache will be automatically invalidated when object is modified (ObjectModifiedEvent is triggered):
>>> from Products.Five.browser import BrowserView >>> class XXX(BrowserView): ... @cache(key) ... def title(self): ... return self.context.title_or_id()
You can disable auto invalidation by providing the auto_invalidate param to @cache decorator:
>>> @cache(key, auto_invalidate=False) ... def title(self): ... return self.context.title_or_id()
In order to manually invalidate memcached cache per object this package provides a browser view called memcache.invalidate. It will invalidate all memcached methods associated with current object's UID:
http://localhost:2020/Plone/front-page/memcache.invalidate
You can also manually invalidate related items and back references:
http://localhost:2020/Plone/front-page/memcache.invalidate/relatedItems http://localhost:2020/Plone/front-page/memcache.invalidate/backRefs
By default this method can be called by users with these roles:
In order to manually invalidate memcached cache per object this package provides a browser view called varnish.invalidate. It will invalidate all memcached methods associated with current object's UID:
http://localhost:2020/Plone/front-page/varnish.invalidate
You can also manually invalidate related items and back references:
http://localhost:2020/Plone/front-page/varnish.invalidate/relatedItems http://localhost:2020/Plone/front-page/varnish.invalidate/backRefs
By default this method can be called by users with these roles:
In order to manually invalidate cache (memcached and varnish) per object this package provides a browser view called cache.invalidate. It will call memcache.invalidate and varnish.invalidate:
http://localhost:2020/Plone/front-page/cache.invalidate
You can also manually invalidate related items and back references:
http://localhost:2020/Plone/front-page/cache.invalidate/relatedItems http://localhost:2020/Plone/front-page/cache.invalidate/backRefs
By default this method can be called by users with these roles:
There is also a Cache Tab per object where you can manually select which cache to invalidate. By default, you can invalidate memcache and varnish. You also have the possibility to invalidate memcache and/or varnish for related items and also fo back references.
This form can be extended with more options. For a more detailed example see eea.pdf
configure.zcml:
<adapter zcml:condition="installed eea.cache" factory=".behavior.ExtraBehavior" /> <adapter zcml:condition="installed eea.cache" factory=".behavior.ExtraSettings" name="eea.pdf.cache.extender" />
behavior.py:
# Model
class IExtraSettings(model.Schema):
""" Extra settings
"""
pdf = schema.Bool(
title=_(u"PDF"),
description=_(u"Invalidate latest generated PDF file"),
required=False,
default=False
)
# Behaviour
class ExtraBehavior(object):
implements(IExtraSettings)
adapts(IPDFAware)
def __init__(self, context):
self.context = context
@property
def pdf(self):
""" PDF
"""
return False
@pdf.setter
def pdf(self, value):
""" Invalidate last generated PDF?
"""
if not value:
return
removePdfFiles()
# Form
class ExtraSettings(extensible.FormExtender):
adapts(IPDFAware, ILayer, SettingsForm)
def __init__(self, context, request, form):
self.context = context
self.request = request
self.form = form
def update(self):
""" Extend form
"""
self.add(IExtraSettings, prefix="extra")
self.move('pdf', after='varnish', prefix='extra')
The Initial Owner of the Original Code is European Environment Agency (EEA). All Rights Reserved.
The eea.cache (the Original Code) is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
More details under docs/License.txt
EEA - European Environment Agency (EU)
- no changes