Products.mcdutils 2.0

A Zope2 product with memcached-backed ZCache and Zope session implementations.

Products.mcdutils

The Products.mcdutils product supplies a replacement for the ZODB-based session data container supplied by the Transience product, shipped with the Zope core prior to Zope 4 and available as a separate package after that. Rather than using a ZODB storage as the backing store for session data, as Transience does, Products.mcdutils stores session data in a cluster of one or more memcached servers.

This approach is a bit of a cheat, as it uses the daemons as primary stores, rather than as caches for results of an expensive query. Nevertheless, the semantics are not a bad match for typical session usage.

Documentation

Documentation is available at https://mcdutils.readthedocs.io/

Bug tracker

A bug tracker is available at https://github.com/dataflake/Products.mcdutils/issues

Attribution

Thanks go to…

• Tres Seaver for implementing this product back in 2006

• Christian Theune for making it available as egg on PyPI in 2011

• Jens Vagelpohl for preparing it for Zope 4 and Python 3

Change log

2.0 (2019-03-28)

• make sure zcache.aggregateKey does not create unsuitable MemCache keys

• allow storing values that don’t conform to IMemCacheMapping

• add ability to set a title for a MemCacheZCacheManager

• Python 3 compatibility

• switch to the python-memcached library and remove the old memcache library module inside this package, which is actually a really old version of python-memcached.

Possible breaking change

The objects returned by Zope’s session data manager are implicitly expected to support Acquisition. Zope’s session data manager uses it to insert itself into the object’s acquisition chain. However, under Python 3 Acquisition can no longer be supported by the session data objects due to a metaclass conflict between the classes permisstence.mapping.PersistentMapping and Acquisition.Explicit. This may break expectations for code consuming the session data objects from this package.

1.0 (2019-03-28)

• Zope 4 compatibility

• documentation using Sphinx

• tox configuration for unit, coverage and code quality tests

• package configuration cleanup

• full flake8 compliance

• add ability to set a title for a MemcacheProxy

• add ability to set a title for a MemcacheSessionDataContainer

0.2b3 (2011-11-21)

• Extend MANIFEST.in to include other missing files (.gif, .pt, .txt)

0.2b2 (2011-11-21)

• Fix source distribution by including README.txt and CHANGES.txt via manifest.

• Include test runner in buildout and fix broken tests.

0.2b1 (2011-11-19)

• Turn product into an egg and release on PyPI.

• Implement a forced refresh of the in-process cache of memcache data at the end of transactions to avoid stale data.

• mapping.py: Added ‘getContainerKey’ method to ‘MemCacheMapping’ in order to make it compatible with the API of the TemporaryFolder version (allows the session testing rig code can generate error messages).

• Added (preliminary) RAMCacheManager replacement.

• Removed proxy’s ‘create’ method, to allow other multiple of data to be stored. The session data container now handles instantiating the mapping.

• Fixed the pickling of mappings correctly, instead of requiring that the proxy pick out the ‘data’ member.

• Expanded API for IProxy to expose more of the memcached client API.

0.1 (2006-05-31)

• CVS tag, ‘mcdutils-0_1’

• Initial public release.