Redis client for TypeScript: ioredis and redis

Redis client for TypeScript: ioredis and redis (node-redis)

In the world of modern web applications and microservices, Redis is one of the most popular in-memory data stores. It is used for caching, session management, task queues, Pub/Sub, and much more. If you are developing in TypeScript, you will need a reliable client to interact with Redis. In this article, we will look at two main options: ioredis and redis (also known as node-redis). Both libraries have excellent TypeScript support, are actively maintained, and provide a wide range of features.

Why do you need a Redis client for TypeScript?

TypeScript adds static typing to JavaScript, making code more predictable and reducing errors at the development stage. A Redis client for TypeScript allows you to:

Work with Redis commands with full type support.
Use autocompletion in the IDE (IntelliSense).
Easily integrate with modern frameworks (NestJS, Express, Koa).
Simplify error handling and reconnections.

The ioredis library

ioredis is a full-featured Redis client that has long been the de facto standard in the Node.js ecosystem. It supports clustering, Pub/Sub, pipelining, transactions (MULTI/EXEC), automatic reconnection, and much more. ioredis is written in TypeScript and provides types out of the box.

Installation

npm install ioredisnpm install @types/ioredis # if you are using TypeScript < 4.0

Connection and basic operations example

import Redis from 'ioredis';

// Create a connection to Redis (default localhost:6379)const redis = new Redis();

// Async function for demonstrationasync function demo() {  try {    // Setting a value    await redis.set('user:1:name', 'Anna');    await redis.set('user:1:age', 30);

    // Getting a value    const name = await redis.get('user:1:name');    console.log('User name:', name);

    // Working with hashes    await redis.hset('user:2', 'name', 'Ivan', 'age', 25);    const user2 = await redis.hgetall('user:2');    console.log('User 2:', user2);

    // Increment    const views = await redis.incr('page:home:views');    console.log('Page views:', views);

    // Setting with expiration (TTL)    await redis.setex('temp:code', 60, '123456');    const ttl = await redis.ttl('temp:code');    console.log('Remaining key TTL:', ttl, 'sec');

  } catch (error) {    console.error('Redis error:', error);  } finally {    // Close the connection    redis.disconnect();  }}

demo();

Cluster and Pub/Sub support

ioredis works great with Redis clusters. A special Cluster class is used for this:

import Redis from 'ioredis';

const cluster = new Redis.Cluster([  { host: '127.0.0.1', port: 7000 },  { host: '127.0.0.1', port: 7001 },  { host: '127.0.0.1', port: 7002 }]);

await cluster.set('foo', 'bar');const value = await cluster.get('foo');console.log(value); // 'bar'

For Pub/Sub, a separate connection is used, as a subscriber cannot execute regular commands:

import Redis from 'ioredis';

const subscriber = new Redis();const publisher = new Redis();

subscriber.subscribe('news', (err, count) => {  console.log(`Subscribed to ${count} channel(s)`);});

subscriber.on('message', (channel, message) => {  console.log(`Received message from channel ${channel}: ${message}`);});

// Publishing a messagepublisher.publish('news', 'Hello from TypeScript!');