multipipe

A better Stream#pipe that creates duplex streams and lets you handle errors in one place. With promise support!

Example

const pipe = require('multipipe')

// pipe streams
const stream = pipe(streamA, streamB, streamC)

// centralized error handling
stream.on('error', fn)

// creates a new stream
source.pipe(stream).pipe(dest)

// optional callback on finish or error
pipe(streamA, streamB, streamC, err => {
  // ...
})

// pass options
pipe(streamA, streamB, streamC, {
  objectMode: false
})

// await finish
await pipe(streamA, streamB, streamC)

Duplex streams

Write to the pipe and you'll really write to the first stream, read from the pipe and you'll read from the last stream.

const stream = pipe(a, b, c)

source
  .pipe(stream)
  .pipe(destination)

In this example the flow of data is:

• source ->
• a ->
• b ->
• c ->
• destination

Error handling

Each pipe forwards the errors the streams it wraps emit, so you have one central place to handle errors:

const stream = pipe(a, b, c)

stream.on('error', err => {
  // called three times
})

a.emit('error', new Error)
b.emit('error', new Error)
c.emit('error', new Error)

API

pipe(stream...[, opts][, cb])

Pass a variable number of streams and each will be piped to the next one.

A stream will be returned that wraps passed in streams in a way that errors will be forwarded and you can write to and/or read from it.

The returned stream is also a Promise that will resolve on finish and reject on error.

Pass an object as the second to last or last argument to pass as options to the underlying stream constructors.

Pass a function as last argument to be called on error or finish of the last stream.

pipe(streams[, cb])

You can also pass an Array of streams if that is more convenient.

Installation

$ npm install multipipe

License

The MIT License (MIT)

Copyright (c) 2014 Segment.io Inc. <[email protected]>

Copyright (c) 2014 Julian Gruber <[email protected]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.