Work with redis "createCluster" throw a TypeError: this.subClient.psubscribe is not a function

[March-mitsuki]

Hello, I'm using the following versions of socket.io and redis, with Node.js v18.13.0

    "@socket.io/redis-adapter": "^8.0.1",
    "express": "^4.18.2",
    "redis": "^4.5.1",
    "socket.io": "^4.5.4",

I have written the following test code based on the documentation https://socket.io/docs/v4/redis-adapter/ and https://github.com/redis/node-redis/blob/master/docs/clustering.md.

import express from "express";
import http from "http";
import { Server as SocketServer } from "socket.io";
import { createAdapter } from "@socket.io/redis-adapter";
import { createCluster } from "redis";

const app = express();
  const server = http.createServer(app);
  const sio = new SocketServer(server);

  const pub = createCluster({
    rootNodes: [
      { url: "redis://192.168.64.1:6379", password: "password" },
      { url: "redis://192.168.64.2:6379", password: "password" },
      { url: "redis://192.168.64.3:6379", password: "password" },
    ],
  });
  const sub = pub.duplicate();

  pub.on("error", (err) => {
    console.log(`[err] PUB redis cluster: ${err}`);
    throw new Error("redis cluster error");
  });
  sub.on("error", (err) => {
    console.log(`[err] SUB redis cluster: ${err}`);
    throw new Error("redis cluster error");
  });

  await pub.connect();
  await sub.connect();

  sio.adapter(createAdapter(pub, sub));

  sio.on("connection", (socket) => {
    console.log(`hello: ${socket.id}`);

    socket.on("disconnect", () => {
      console.log(`goodbye: ${socket.id}`);
    });

    socket.onAny((evt, data) => {
      console.log(`from: ${socket.id}`, `- [${evt}]: ${data}`);
    });
  });

  app.get("/ping", (req, res) => {
    res.send("pong");
    return;
  });

  server.listen(5139, () => {
    console.log("server is listen on: 5139");
  });

But when I run this code, I get a TypeError:

TypeError: this.subClient.psubscribe is not a function
    at new RedisAdapter (/path/to/project/node_modules/@socket.io/redis-adapter/dist/index.js:88:28)
    at new <anonymous> (/path/to/project/node_modules/@socket.io/redis-adapter/dist/index.js:48:16)
    at Namespace._initAdapter (/path/to/project/node_modules/socket.io/dist/namespace.js:93:24)
    at Server.adapter (/path/to/project/node_modules/socket.io/dist/index.js:166:17)
    at initServer (file:///path/to/project/src/server.js:35:7)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

Node.js v18.13.0

I have tested this cluster pubsub with redis-cli and everything works fine when using redis-cli -c.

When I don't use createCluster and switch to use createClient everything works fine.

- const pub = createCluster({
-   rootNodes: [
-     { url: "redis://192.168.64.1:6379", password: "password" },
-     { url: "redis://192.168.64.2:6379", password: "password" },
-     { url: "redis://192.168.64.3:6379", password: "password" },
-   ],
- });

+ const pub = createClient({
+   url: "redis://localhost:6379",
+   password: "password",
+ });

When I run this code, everything looks ok.

This is very strange, can anyone help me?

[darrachequesne]

Hi! It seems the redis package does not currently support PUB/SUB within a cluster: redis/node-redis#2065

I think you will have to use the ioredis package for now:

const io = require('socket.io')(3000);
const redisAdapter = require('@socket.io/redis-adapter');
const Redis = require('ioredis');

const startupNodes = [
  {
    port: 6380,
    host: '127.0.0.1'
  },
  {
    port: 6381,
    host: '127.0.0.1'
  }
];

const pubClient = new Redis.Cluster(startupNodes);
const subClient = pubClient.duplicate();

io.adapter(redisAdapter(pubClient, subClient));

[March-mitsuki]

@darrachequesne I switch to use ioredis, everything works fine. Thankyou! ☺️