Caching & Redis
Cache-aside, TTL, invalidation, hot keys, and in-memory lookup patterns at scale.
How to Build a Redis Leaderboard with ZREVRANGE in Python
Build a sorted leaderboard by storing player scores as a Redis sorted set and reading the top scores with ZREVRANGE in Python.
import redis
import random
# Connect to local Redis (ensure Redis is running on localhost:6379)
r = redis.Redis(host="localhost", port=6379, db=0, decode_responses=True)
# Clear any existing test data
r.delete("game_scores")
# Simulate player scores
players = ["alice", "bob", "charlie", "dave", "eve"]
for player in…Redis SADD SMEMBERS Set Mock in Python
A lightweight mock of Redis SADD and SMEMBERS using Python sets for testing or local caching.
class RedisSetMock:
def __init__(self):
self.sets = {}
def sadd(self, key, *members):
if key not in self.sets:
self.sets[key] = set()
before = len(self.sets[key])
self.sets[key].update(members)
return len(self.sets[key]) - before
def smembers(self, key)…Browse by section
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Caching & Redis — Python code examples
What you will find here
This page collects caching & redis snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.
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