NodeJS

Github	https://github.com/zeromq/zeromq.js/
npm	https://www.npmjs.com/package/zeromq

Installation

To install ZeroMQ for Node, download and install the package from npm.

$ npm install zeromq

ZeroMQ.js API reference

Examples using zeromq

Push/Pull

This example demonstrates how a producer pushes information onto a socket and how a worker pulls information from the socket.

producer.js

Creates a producer to push information onto a socket.

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Push()

  await sock.bind("tcp://127.0.0.1:3000")
  console.log("Producer bound to port 3000")

  while (true) {
    await sock.send("some work")
    await new Promise(resolve => {
      setTimeout(resolve, 500)
    })
  }
}

run()

worker.js

Creates a worker to pull information from the socket.

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Pull()

  sock.connect("tcp://127.0.0.1:3000")
  console.log("Worker connected to port 3000")

  for await (const [msg] of sock) {
    console.log("work: %s", msg.toString())
  }
}

run()

Pub/Sub

This example demonstrates using zeromq in a classic Pub/Sub, Publisher/Subscriber, application.

Publisher: publisher.js

Create the publisher which sends messages.

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Publisher()

  await sock.bind("tcp://127.0.0.1:3000")
  console.log("Publisher bound to port 3000")

  while (true) {
    console.log("sending a multipart message envelope")
    await sock.send(["kitty cats", "meow!"])
    await new Promise(resolve => {
      setTimeout(resolve, 500)
    })
  }
}

run()

Subscriber: subscriber.js

Create a subscriber to connect to a publisher’s port to receive messages.

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Subscriber()

  sock.connect("tcp://127.0.0.1:3000")
  sock.subscribe("kitty cats")
  console.log("Subscriber connected to port 3000")

  for await (const [topic, msg] of sock) {
    console.log(
      "received a message related to:",
      topic,
      "containing message:",
      msg,
    )
  }
}

run()

Req/Rep

This example illustrates a request from a client and a reply from a server.

Client: client.js

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Request()

  sock.connect("tcp://127.0.0.1:3000")
  console.log("Producer bound to port 3000")

  await sock.send("4")
  const [result] = await sock.receive()

  console.log(result)
}

run()

Server: server.js

const zmq = require("zeromq")

async function run() {
  const sock = new zmq.Reply()

  await sock.bind("tcp://127.0.0.1:3000")

  for await (const [msg] of sock) {
    await sock.send(2 * parseInt(msg, 10))
  }
}

run()

TypeScript

This library provides typings for TypeScript version 3.0.x and later.

import {Request} from "zeromq"
// or as namespace
import * as zmq from "zeromq"

const reqSock = new Request()
//...
const repSock = new zmq.Reply()

More examples More advanced examples can be found in the examples directory of this repository.

Or you can browse the API reference documentation to see all socket types, methods & options as well as more detailed information about how to apply them.