RedChannel

Simplified pub/sub messaging with Redis

Warning

This library is intended for fast, fire-and-forget messaging, in situations where dropped messages are acceptable. This is due to the nature of Redis pub/sub. Additionally, if you intend to use this library at scale, please set the events parameter in the constructor to false. This will improve performance, but prevent the use of event-specific listeners.

Available Scripts

In the project directory, you can run:

npm test

Runs the library test suite, and reports the results of each test.

npm build

Builds the library for production to the lib folder.
It correctly bundles the library in production mode and optimizes the build for the best performance.

npm lint

Lints the project files.

Usage

JavaScript (Subscriber)

const Redis = require('ioredis');
const { RedSubscriber } = require('redchannel');

const client = new Redis();
// Use "new RedSubscriber(client, false)" if you intend to use this library at scale
const channel = new RedSubscriber(client);

async function main() {
    // Subscribe to all messages on "global:logs".
    await channel.subscribe(['global:logs']);

    // (Generic listener) Process all messages published on "global:logs".
    channel.on('message', (channel, message) => {
        channel === 'global:logs' && console.log(message);
        // Foo
    });

    // (Event specific listener) Process all messages published on "global:logs".
    channel.on('global:logs', (message) => {
        console.log(message);
        // Foo
    });

    // Check if subscribed to a channel
    console.log(channel.subscribed('global:logs'));
    // true
    
    // Unsubscribe from all messages on "global:logs".
    await channel.unsubscribe(['global:logs']);

    // Check if subscribed to a channel
    console.log(channel.subscribed('global:logs'));
    // false

    // Print current subscriptions
    console.log(channel.subscriptions());
    // []

    // Subscribe to all messages on "global:logs".
    await channel.subscribe('global:events');

    // Print current subscriptions
    console.log(channel.subscriptions());
    // ['global:events']

    // (Generic listener) Process all messages published on "global:events".
    channel.on('message', (channel, message) => {
        channel === 'global:events' && console.log(message);
        // { foo: 'bar' }
    });
    
    // Clean up subscriptions. After this point a new instance must be created
    await channel.destroy();

    // Remove all event listeners (your responsibility).
    channel.removeAllListeners();
}

JavaScript (Publisher)

const Redis = require('ioredis');
const { RedPublisher } = require('redchannel');

const client = new Redis();
const channel = new RedPublisher(client);

async function main() {
    // Publish message to all listeners on "global:logs";
    await channel.publish('global:logs', 'Foo');

    // Publish message to all listeners on "global:events";
    await channal.publish('global:events', { foo: 'bar' });
}

TypeScript (Subscriber)

import Redis = require("ioredis");
import { RedSubscriber } from "redchannel";

const client = new Redis();
// Use "new RedSubscriber(client, false)" if you intend to use this library at scale
const channel = new RedSubscriber(client);

async function main(): Promise<void> {
    // Subscribe to all messages on "global:logs".
    await channel.subscribe(["global:logs"]);

    // (Generic listener) Process all messages published on "global:logs".
    channel.on("message", (channel: string, message: any) => {
        channel === "global:logs" && console.log(message);
        // Foo
    });

    // (Event specific listener) Process all messages published on "global:logs".
    channel.on("global:logs", (message: any) => {
        console.log(message);
        // Foo
    });

    // Check if subscribed to a channel
    console.log(channel.subscribed("global:logs"));
    // true
    
    // Unsubscribe from all messages on "global:logs".
    await channel.unsubscribe(["global:logs"]);

    // Check if subscribed to a channel
    console.log(channel.subscribed("global:logs"));
    // false

    // Print current subscriptions
    console.log(channel.subscriptions());
    // []

    // Subscribe to all messages on "global:logs".
    await channel.subscribe("global:events");

    // Print current subscriptions
    console.log(channel.subscriptions());
    // ['global:events']

    // (Generic listener) Process all messages published on "global:events".
    channel.on("message", (channel: string, message: any) => {
       channel === "global:events" && console.log(message);
        // { foo: 'bar' }
    });
    
    // Clean up subscriptions. After this point a new instance must be created
    await channel.destroy();

    // Remove all event listeners (your responsibility).
    channel.removeAllListeners();
}

TypeScript (Publisher)

import Redis = require("ioredis");
import { RedPublisher } from "redchannel";

const client = new Redis();
const channel = new RedPublisher(client);

async function main(): Promise<void> {
    // Publish message to all listeners on "global:logs";
    await channel.publish("global:logs", "Foo");

    // Publish message to all listeners on "global:events";
    await channal.publish("global:events", { foo: "bar" });
}

License

MIT