npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@socket-mesh/stream-demux

v10.1.5

Published

A consumable stream demultiplexer.

Downloads

37

Readme

stream-demux

An consumable stream demultiplexer.

Lets you write data to multiple consumable streams from a central place without keeping any references to those streams. The StreamDemux class returns streams of class DemuxedConsumableStream (base class ConsumableStream).
See https://github.com/SocketCluster/consumable-stream

This library uses a queue which is implemented as a singly-linked list; this allows each loop to consume at its own pace without missing any events (supports nested await statements). An 'event' in the queue can be garbage-collected as soon as the slowest consumer moves its pointer past it.

Installation

npm install stream-demux

Usage

Consuming using async loops

let demux = new StreamDemux();

(async () => {
  // Consume data from 'abc' stream.
  let substream = demux.stream('abc');
  for await (let packet of substream) {
    console.log('ABC:', packet);
  }
})();

(async () => {
  // Consume data from 'def' stream.
  let substream = demux.stream('def');
  for await (let packet of substream) {
    console.log('DEF:', packet);
  }
})();

(async () => {
  // Consume data from 'def' stream.
  // Can also work with a while loop for older environments.
  // Can have multiple loops consuming the same stream at
  // the same time.
  // Note that you can optionally pass a number n to the
  // createConsumer(n) method to force the iteration to
  // timeout after n milliseconds of inactivity.
  let consumer = demux.stream('def').createConsumer();
  while (true) {
    let packet = await consumer.next();
    if (packet.done) break;
    console.log('DEF (while loop):', packet.value);
  }
})();

(async () => {
  for (let i = 0; i < 10; i++) {
    await wait(10);
    demux.write('abc', 'message-abc-' + i);
    demux.write('def', 'message-def-' + i);
  }
  demux.close('abc');
  demux.close('def');
})();

// Utility function for using setTimeout() with async/await.
function wait(duration) {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve();
    }, duration);
  });
}

Consuming using the once method

// Log the next received packet from the abc stream.
(async () => {
  // The returned promise never times out.
  let packet = await demux.stream('abc').once();
  console.log('Packet:', packet);
})();

// Same as above, except with a timeout of 10 seconds.
(async () => {
  try {
    let packet = await demux.stream('abc').once(10000);
    console.log('Packet:', packet);
  } catch (err) {
    // If no packets are written to the 'abc' stream before
    // the timeout, an error will be thrown and handled here.
    // The err.name property will be 'TimeoutError'.
    console.log('Error:', err);
  }
})();

Goal

The goal of this module is to facilitate functional programming patterns which decrease the probability of memory leaks and race conditions. It serves as an alternative to callback-based event handling.