Node.js and Redis: Race Condition with Concurrent Set Operations
I'm stuck trying to I'm migrating some code and I'm working with a race condition scenario with my Node.js application while using Redis for caching..... I'm trying to set a value in Redis and then immediately read it back. However, under high load, sometimes the read operation retrieves an old value or returns `null`, even though the write operation was successfully acknowledged. I'm using the `ioredis` library (version 4.17.3) for Redis operations. Here’s a simplified version of my code: ```javascript const Redis = require('ioredis'); const redis = new Redis(); async function updateCache(key, value) { await redis.set(key, value); const result = await redis.get(key); console.log(`Value for ${key}: ${result}`); return result; } async function handleRequest(req, res) { const key = 'myKey'; const value = 'newValue'; const promises = []; for (let i = 0; i < 100; i++) { promises.push(updateCache(key, value)); } await Promise.all(promises); res.send('Cache updated.'); } ``` When I run this code under load, I occasionally see console logs that show the old value instead of `newValue`. I’ve tried increasing the delay between set and get operations, but that doesn't seem to solve the question. Additionally, I’ve verified that there are no other processes modifying the same Redis key concurrently. How can I ensure that the value read from Redis is always the latest after a set operation? Is there a recommended pattern to handle this scenario effectively? The project is a web app built with Javascript. Has anyone else encountered this? Any help would be greatly appreciated! What would be the recommended way to handle this? What am I doing wrong?