Registry / messaging / socket.io-redis-adapter

socket.io-redis-adapter

library8.4.6jsnpmunverified

Redis-based adapter for Socket.IO that enables broadcasting events between multiple Socket.IO server instances via Redis Pub/Sub. Version 8.4.6 (stable), maintained by the Socket.IO team. Ships TypeScript types. Requires socket.io-adapter ^2.4.0 peer dependency. Supports CommonJS, ES modules, and TypeScript. Key differentiator: uses two separate Redis clients (pub/sub) for reliability; supports both standard and sharded Pub/Sub (Redis 7.0+). Migration from legacy socket.io-redis package requires API changes.

messaging

npm install socket.io-redis-adapter

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · SOCKET.IO-REDIS-AD

socket.io-redis-adapter

messagingjavascriptv8.4.6

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

createAdapter

✓ import { createAdapter } from 'socket.io-redis-adapter'

✗ const createAdapter = require('socket.io-redis'); // wrong package name

Package renamed from 'socket.io-redis' to 'socket.io-redis-adapter' in v6. Always use the new name.

RedisAdapter

✓ import { RedisAdapter } from 'socket.io-redis-adapter'

✗ import RedisAdapter from 'socket.io-redis-adapter'; // default import does not exist

Only named exports are provided. No default export.

Create a Socket.IO server with Redis adapter using two Redis clients (pub/sub). Must call connect() for each client (redis@4+).

import { Server } from 'socket.io'; import { createClient } from 'redis'; import { createAdapter } from 'socket.io-redis-adapter'; const io = new Server(); const pubClient = createClient({ url: process.env.REDIS_URL ?? 'redis://localhost:6379' }); const subClient = pubClient.duplicate(); Promise.all([ pubClient.connect(), subClient.connect() ]).then(() => { io.adapter(createAdapter(pubClient, subClient)); io.listen(3000); console.log('Socket.IO server with Redis adapter listening on port 3000'); });

Debug

Known issues

breakingPackage renamed from 'socket.io-redis' to 'socket.io-redis-adapter' in version 6.0.0. Old package deprecated.

fix

Replace require('socket.io-redis') with require('socket.io-redis-adapter') and update imports to named export createAdapter.

affects: <6.0.0

breakingredis@4+ requires explicit connect() calls. Not calling pubClient.connect()/subClient.connect() causes 'start' event to fail silently.

fix

Add await pubClient.connect() and await subClient.connect() before calling io.adapter().

affects: >=8.0.0

gotchaUsing the same Redis client instance for both pub and sub leads to message deduplication issues and potential deadlocks.

fix

Always use pubClient.duplicate() to create a separate sub client.

affects: >=1.0.0

deprecatedUsage with ioredis client is deprecated. Prefer 'redis' package (node-redis) v4+.

fix

Switch from ioredis to redis package. If using ioredis, ensure compatibility via custom adapter options.

affects: >=8.0.0

Errors

Common errors & fixes

Error: Cannot find module 'socket.io-redis'

Package renamed to 'socket.io-redis-adapter' but code still imports the old name.

fix

npm uninstall socket.io-redis && npm install socket.io-redis-adapter && change imports to 'socket.io-redis-adapter'

TypeError: pubClient.connect is not a function

Using redis@3 (no need for connect()) or ioredis but calling connect() like redis@4. Or using redis@4 and not importing createClient correctly.

fix

Check Redis client version. For redis@3: don't call connect(). For redis@4: import { createClient } from 'redis' and call client.connect(). For ioredis: use new Redis() and don't call connect().

Upgrade

Version history

8.4.6latest on npm

Audit

Dependencies

socket.io-adapteroptionalPeer dependency required for adapter interface

redisoptionalApplication must install a Redis client (e.g., ioredis or node-redis) to create pub/sub clients

Agent activity

16 hits · last 30 days

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Resources

githubssh://git@github.com/sorilove/socket.io-redis-adapter ↗

packagesocket.io-redis-adapter ↗

homepagehttps://github.com/sorilove/socket.io-redis-adapter#readme ↗