===================== Redis Tools (retools)

retools is a package of Redis <http://redis.io/>_ tools. It's aim is to provide a variety of Redis backed Python tools that are always 100% unit tested, fast, efficient, and utilize the capabilities of Redis.

retools is available on PyPI at https://pypi.python.org/pypi/retools

.. image:: https://badge.fury.io/py/retools.svg :target: http://badge.fury.io/py/retools

Current tools in retools:

Caching
Global Lock
Queues - A worker/job processing system similar to Celery <http://www.celeryproject.org/> but based on how Ruby's Resque <https://github.com/defunkt/resque> system works.

.. image:: https://secure.travis-ci.org/bbangert/retools.png?branch=master :alt: Build Status :target: https://secure.travis-ci.org/bbangert/retools

Caching

A high performance caching system that can act as a drop-in replacement for Beaker's caching. Unlike Beaker's caching, this utilizes Redis for distributed write-locking dogpile prevention. It also collects hit/miss cache statistics along with recording what regions are used by which functions and arguments.

Example:

.. code-block:: python

from retools.cache import CacheRegion, cache_region, invalidate_function

CacheRegion.add_region('short_term', expires=3600)

@cache_region('short_term')
def slow_function(*search_terms):
    # Do a bunch of work
    return results

my_results = slow_function('bunny')

# Invalidate the cache for 'bunny'
invalidate_function(slow_function, [], 'bunny')

Differences from Beaker

Unlike Beaker's caching system, this is built strictly for Redis. As such, it adds several features that Beaker doesn't possess:

A distributed write-lock so that only one writer updates the cache at a time across a cluster.
Hit/Miss cache statistics to give you insight into what caches are less effectively utilized (and may need either higher expiration times, or just not very worthwhile to cache).
Very small, compact code-base with 100% unit test coverage.

Locking

A Redis based lock implemented as a Python context manager, based on Chris Lamb's example <http://chris-lamb.co.uk/2010/06/07/distributing-locking-python-and-redis/>_.

Example:

.. code-block:: python

from retools.lock import Lock

with Lock('a_key', expires=60, timeout=10):
    # do something that should only be done one at a time

License

retools is offered under the MIT license.

Authors

retools is made available by Ben Bangert.

bbangert / retools

readme