A stream that emits multiple other streams one after another (streams3)

Usage no npm install needed!

<script type="module">
  import nearformMultistream from 'https://cdn.skypack.dev/@nearform/multistream';


This fork of multistream includes this patch by @ronag, and no other changes. This exists just to let Clinic.js use that patch. While the PR has not passed review yet, it is unlikely to make things worse in our specific case.

multistream travis npm downloads javascript style guide

A stream that emits multiple other streams one after another (streams3)

Sauce Test Status

Simple, robust streams3 version of combined-stream. Allows you to combine multiple streams into a single stream. When the first stream ends, the next one starts, and so on, until all streams are consumed.

This module is used by WebTorrent, specifically create-torrent.


npm install multistream


Use multistream like this:

var MultiStream = require('multistream')
var fs = require('fs')

var streams = [
  fs.createReadStream(__dirname + '/numbers/1.txt'),
  fs.createReadStream(__dirname + '/numbers/2.txt'),
  fs.createReadStream(__dirname + '/numbers/3.txt')

new MultiStream(streams).pipe(process.stdout) // => 123

You can also create an object-mode stream with MultiStream.obj(streams).

To lazily create the streams, wrap them in a function:

var streams = [
  fs.createReadStream(__dirname + '/numbers/1.txt'),
  function () { // will be executed when the stream is active
    return fs.createReadStream(__dirname + '/numbers/2.txt')
  function () { // same
    return fs.createReadStream(__dirname + '/numbers/3.txt')

new MultiStream(streams).pipe(process.stdout) // => 123

Alternatively, streams may be created by an asynchronous "factory" function:

var count = 0
function factory (cb) {
  if (count > 3) return cb(null, null)
  setTimeout(function () {
    cb(null, fs.createReadStream(__dirname + '/numbers/' + count + '.txt'))
  }, 100)

new MultiStream(factory).pipe(process.stdout) // => 123



MIT. Copyright (c) Feross Aboukhadijeh.