primus-cluster

primus-cluster

Primus cluster runs Primus accross multiple servers, it use Redis to store data and distribute messages across Primus instances. For more informations you can see Redis Pub/Sub.

This project is a fork of the original project primus-redis that is not compatible with other Primus plugins and with Primus v2+.

This plugin works with primus-emitter, primus-rooms, and primus-resource.

Usage

const http = require("http");
const Primus = require("primus");
const PrimusCluster = require("primus-cluster");
const
const server = http.createServer();
const primus = new Primus(server);

primus.plugin("cluster", PrimusCluster);

Options

redis

Type: Object or Function

If you specify an object, the properties will be used to call redis.createClient method. The redis module used will be the Redis module installed. This project doesn't have node_redis module as dependency.

new Primus(server, {
  cluster: {
    redis: {
      port: 6379,
      host: "127.0.0.1",
      connect_timeout: 200,
    },
  },
});

If you specify a function, it will be called to create redis clients.

const redis = require("redis");

new Primus(server, {
  cluster: {
    redis: createClient,
  },
});

function createClient() {
  const client = redis.createClient();
  client.select(1); // Choose a custom database.
  return client;
}

prefix

Type: String

Prefix added to every redis key and default channel, default channel is "primus-cluster:".

new Primus(server, {
  cluster: {
    prefix: "my-client:",
  },
});

channel

Type: String

The name of the channel to use, the default channel is ${prefix}pubsub.

new Primus(server, {
  cluster: {
    channel: "my-client:awesome-channel",
  },
});

ttl

Type: Number

The TTL of the data stored in redis in second, the default value is 86400 (1 day). If you use primus-rooms, Primus cluster will store rooms data in redis.

new Primus(server, {
  cluster: {
    ttl: 86400,
  },
});

Use with other plugins

When you use primus-redis with other plugins, you must take care of calling primus-cluster after all plugins.

primus.plugin("rooms", PrimusRooms);
primus.plugin("emitter", PrimusEmitter);
primus.plugin("cluster", PrimusCluster);

License

MIT

Changelog

2.0.0 (2021-09-15)

⚠ BREAKING CHANGES

• Primus v8 is required, Node.js >=14 is tested and supported.

Features

• allow prefixing redis keys & channel (0e39c2c)

• modernize project (aa197fd)