Welcome to redis-py-cluster’s documentation!

This project is a port of redis-rb-cluster by antirez, with alot of added functionality. The original source can be found at https://github.com/antirez/redis-rb-cluster.

The source code is available on github.

Installation

Latest stable release from pypi

$ pip install redis-py-cluster

or from source code

$ python setup.py install

Usage example

Small sample script that shows how to get started with RedisCluster. It can also be found in the file exmaples/basic.py

>>> from rediscluster import StrictRedisCluster

>>> # Requires at least one node for cluster discovery. Multiple nodes is recommended.
>>> startup_nodes = [{"host": "127.0.0.1", "port": "7000"}]

>>> # Note: See note on Python 3 for decode_responses behaviour
>>> rc = StrictRedisCluster(startup_nodes=startup_nodes, decode_responses=True)

>>> rc.set("foo", "bar")
True
>>> print(rc.get("foo"))
'bar'

Note

Python 3

Since Python 3 changed to Unicode strings from Python 2’s ASCII, the return type of most commands will be binary strings, unless the class is instantiated with the option decode_responses=True. In this case, the responses will be Python 3 strings (Unicode). For the init argument decode_responses, when set to False, redis-py-cluster will not attempt to decode the responses it receives. In Python 3, this means the responses will be of type bytes. In Python 2, they will be native strings (str). If decode_responses is set to True, for Python 3 responses will be str, for Python 2 they will be unicode.

Dependencies & supported python versions

  • Python: redis >= 2.10.2, <= 2.10.5 is required. Older versions in the 2.10.x series can work but using the latest one is allways recommended.
  • Optional Python: hiredis >= 0.2.0. Older versions might work but is not tested.
  • A working Redis cluster based on version >= 3.0.0 is required. Only 3.0.x releases is supported.

Supported python versions

  • 2.7
  • 3.3
  • 3.4.1+ (See note)
  • 3.5
  • 3.6

Experimental:

  • 3.7-dev

Note

Python 3.4.0

A segfault was found when running redis-py in python 3.4.0 that was introduced into the codebase in python 3.4.0. Because of this both redis-py and redis-py-cluster will not work when running with 3.4.0. This lib has decided to block the lib from execution on 3.4.0 and you will get a exception when trying to import the code. The only solution is to use python 3.4.1 or some other higher minor version in the 3.4 series.

Regarding duplicate pypi and python naming

It has been found that the python module name that is used in this library (rediscluster) is already shared with a similar but older project.

This lib will not change the naming of the module to something else to prevent collisions between the libs.

My reasoning for this is the following

  • Changing the namespace is a major task and probably should only be done in a complete rewrite of the lib, or if the lib had plans for a version 2.0.0 where this kind of backwards incompatibility could be introduced.
  • This project is more up to date, the last merged PR in the other project was 3 years ago.
  • This project is aimed for implement support for the cluster support in 3.0+, the other lib do not have that right now, but they implement almost the same cluster solution as the 3.0+ but in much more in the client side.
  • The 2 libs is not compatible to be run at the same time even if the name would not collide. It is not recommended to run both in the same python interpreter.

An issue has been raised in each repository to have tracking of the problem.

redis-py-cluster: https://github.com/Grokzen/redis-py-cluster/issues/150

rediscluster: https://github.com/salimane/rediscluster-py/issues/11