Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/lethain/Redis-Python-Datastructures

simple python datastructure wrappings for redis
https://github.com/lethain/Redis-Python-Datastructures

Last synced: 13 days ago
JSON representation

simple python datastructure wrappings for redis

Awesome Lists containing this project

README 

        
[redis]: http://code.google.com/p/redis/ "Redis"

[redis-py]: http://github.com/andymccurdy/redis-py "Redis-Py"



*If you'd like to be a contributor, send me a note! I'd be more than glad to pass this over to a more active maintainer.*



This package exposes [Redis][redis] backed datastructures which bring together

standard Python syntax with persistent in-memory storage. Redis operations

are all atomic as well, meaning that a thoughtful approach can use them

concurrently on multiple machines.



Utimately, a trivial wrapper around [Redis-Py][redis-py].



## Simple Installation



The simplest approach to installation is:



    pip install redis

    pip install -e git+https://github.com/lethain/Redis-Python-Datastructures.git#egg=redis_ds



## Installation for development



For development, you should checkout the repository,

and install it into a [virtualenv](http://www.virtualenv.org/en/latest/):



    # get the code

    git clone https://github.com/lethain/Redis-Python-Datastructures.git

    cd Redis-Python-Datastructures.git



    # create and activate a virtualenv if you don't have one already

    virtualenv env

    . ./activate



    # install it

    pip install -r requirements.txt

    python setup.py develop



## Running tests



With some embarassment, the tests currently run against local Redis using keys

prefixed with "test_rds.", and taking great pains not to delete any other keys,

so if you have a toy Redis node, the tests will not cause any harm, but you really

shouldn't run the tests against a Redis node you care deeply about.



Run them via:



    python src/redis_ds/tests.py



The tests really ought to be run against a mocked out version of Redis, but that

work hasn't been done yet.



# Usage



This section covers how to use this library to interface with Redis.



## Dictionary via Redis Strings



Using the entire Redis cluster as a dictionary:



    >>> from redis_ds.redis_dict import RedisDict

    >>> x = RedisDict()

    >>> x

    {}

    >>> x['a'] = 100

    >>> x

    {'a': '100'}

    >>> x['a']

    '100'

    >>> x['b']

    >>> len(x)

    1



## Dictionaries via Redis Hashes



Using Redis hashes we can store multiple dictionaries in

one Redis server.



    >>> from redis_ds.redis_hash_dict import RedisHashDict

    >>> x = RedisHashDict("some_hash_key")

    >>> x

    {}

    >>> x['a'] = 100

    >>> x

    {'a': '100'}

    >>> x['a']

    '100'

    >>> x['b']

    >>> len(x)

    1



## Lists via Redis Lists



We also have a kind-of-sort-off implementation of a list which

certainly doesn't have the full flexibility of a Python list,

but is persistent, synchronized and sharable.



    >>> from redis_ds.redis_list import RedisList

    >>> x = RedisList("my-list")

    >>> x

    RedisList([])

    >>> x.append("a")

    1

    >>> x.append("b")

    2

    >>> x

    RedisList(['a', 'b'])

    >>> x[0]

    'a'

    >>> x.pop()

    'b'

    >>> x

    RedisList(['a'])



It also provides access to blocking versions of pop, which

with a little creativity you can use to create a message queue

with workers.



    >>> x.pop(blocking=True)

    'a'



Woohoo.



## Sets



Sets are also available thanks to work by [@hhuuggoo](https://github.com/hhuuggoo):



    >>> from redis_ds.redis_set import RedisSet

    >>> x = RedisSet()

    >>> x.add("a")

    >>> x.add("a")

    >>> x.add("b")

    >>> x.add("b")

    >>> len(x)

    2

    >>> 'a' in x

    True

    >>> 'c' in x

    False

    >>> x.pop()

    'a'

    >>> len(x)

    1



## Serializing Values Stored in Redis



Thanks to work by [@hhuuggoo](https://github.com/hhuuggoo), this library also

supports serializing values before storing them in Redis. Each class has a

serialized equivalent, for example the above hashmap example becomes:



    >>> from redis_ds.redis_hash_dict import PickleRedisHashDict

    >>> y = PickleRedisHashDict('some_other_key')

    >>> y

    {}

    >>> y['a'] = {'obj': 'ect'}

    >>> y

    {'a': {'obj': 'ect'}}

    >>> y['a']['obj']

    'ect'



The same can be done using JSON instead of Pickle by changing it to:



    >>> from redis_ds.redis_hash_dict import JSONRedisHashDict



and so on. The same is true for ``RedisList`` which has ``PickleRedisList``

and ``JSONRedisList``, and so on.