Skip to main content
Join the official 2019 Python Developers SurveyStart the survey!

Basic Redis caching for functions

Project description

python-redis-cache

Simple redis cache for Python functions

Requirements

  • Redis 5+
  • Python 3.6+

How to install

pip install python-redis-cache

How to use

from redis import StrictRedis
from redis_cache import RedisCache

client = StrictRedis(host="redis", decode_responses=True)
cache = RedisCache(redis_client=client)


@cache.cache()
def my_func(arg1, arg2):
    result = some_expensive_operation()
    return result

# Use the function
my_func(1, 2)

# Call it again with the same arguments and it will use cache
my_func(1, 2)

# Invalidate a single value
my_func.invalidate(1, 2)

# Invalidate all values for function
my_func.invalidate_all()

Limitations and things to know

Arguments and return types must be JSON serializable by default. You can override the serializer, but be careful with using Pickle. Make sure you understand the security risks. Pickle should not be used with untrusted values. https://security.stackexchange.com/questions/183966/safely-load-a-pickle-file

  • ttl - is based on the time from when it's first inserted in the cache, not based on the last access
  • limit - The limit will revoke keys (once it hits the limit) based on FIFO, not based on LRU

API

RedisCache(redis_client, prefix="rc", serializer=dumps, deserializer=loads)

RedisCache.cache(ttl=None, limit=None, namespace=None)

# Cached function API

# Returns a cached value, if it exists in cache. Saves value in cache if it doesn't exist
cached_func(*args, *kwargs)

# Invalidates a single value
cached_func.invalidate(*args, **kwargs)

# Invalidates all values for cached function
cached_func.invalidate_all()
  • prefix - The string to prefix the redis keys with
  • serializer/deserializer - functions to convert arguments and return value to a string (user JSON by default)
  • ttl - The time in seconds to cache the return value
  • namespace - The string namespace of the cache. This is useful for allowing multiple functions to use the same cache. By default its f'{function.__module__}.{function.__file__}'

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for python-redis-cache, version 1.1.0
Filename, size File type Python version Upload date Hashes
Filename, size python-redis-cache-1.1.0.tar.gz (4.7 kB) File type Source Python version None Upload date Hashes View hashes

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN SignalFx SignalFx Supporter DigiCert DigiCert EV certificate StatusPage StatusPage Status page