Redis Short Course

01-What is Redis and why it exists

Introduction of redis

• Read query will optimised
• same data, hot data, response fast
• example (zomato, blinkit menu)

Features provided by redis

Cache

Session Store

OTP Store

Rate Limiting

JOB Queue

Redis

In redis everthing is stored in key value pair. redis is also known as key value store.

TTL ⇒ is very imprtant in redis

Note ⇒ Redis is not a solution for every problem.

02-Complete local setup to learn Redis

docker-compose.yml

services:
  redis:
    image: redis:7-alpine
    container_name: redis-container
    ports:
      - "6379:6379"
    volumes:
      - redis-data:/data

  mongo:
    image: mongo:7
    container_name: mongodb
    ports:
      - "27017:27017"
    volumes:
      - mongo-data:/data/db

volumes:
  redis-data:
  mongo-data:

server.js file

import express from "express";
import "dotenv/config";
import Redis from "ioredis";
import mongoose from "mongoose";

const app = express();
const redis = new Redis(process.env.REDIS_URL);
const PORT = process.env.PORT;

app.use(express.json());

app.get("/", (_, res) => {
    res.send("welcome to server...");
});

app.post("/setOtp", async (req, res) => {
    try {
        console.log("body is:", req.body);
        const { otp } = req.body;
        await redis.set("otp", otp);
        res.json({
            msg: "otp set",
        });
    } catch (error) {
        console.log("error during otp save", error);
    }
});

app.listen(PORT, () => console.log(`server is running on port:${PORT}`));

package.json file

{
    "name": "redis-chaicode",
    "version": "1.0.0",
    "description": "",
    "main": "index.js",
    "scripts": {
        "dev": "npx nodemon src/index.js"
    },
    "keywords": [],
    "author": "",
    "license": "ISC",
    "type": "module",
    "dependencies": {
        "dotenv": "^17.4.2",
        "express": "^5.2.1",
        "ioredis": "^5.10.1",
        "mongoose": "^9.6.2"
    }
}

.env file

PORT="3000"
REDIS_URL="redis://localhost:6379"