pup

Pipe and Unpipe streams

Overview

As of node 0.8.x, there is no way to unpipe streams. This module attemps to fill the gap by providing a pipe(source, destination[, options]) and unpipe(source, destination) functions working in tandem, to do piping and unpiping of streams.

Usage

Install with

npm install pup

Two functions are provided:

• pipe(source, destination[, options]) : to be used to setup a pipe from source to destination. Same signature as the Stream#pipe method.
• unpipe(source, destination) : remove the pipe between source and destination. If there are many of those, only the first one is removed. Return true on successful removal, false otherwise.

Example

var fs = require('fs')
var pup = require('pup')
 
var source = fs.readFileStream('test')
var wrong_destination = fs.readWriteStream('test2')
var destination = fs.readWriteStream('test.bak')
 
// Pipe to one destination
source.pause()
pup.pipe(source, wrong_destination)
 
// Then remove it and pipe to another
pup.unpipe(source, wrong_destination)
pup.pipe(source, destination)
 
// Copy the file test.js, which should only end up in test.bak
source.resume()

Restrictions

This is a bit of a hack that relies on the assumption that there is the same cleanup() listener setup by the Stream#pipe method for the end event on the source and on the destination.

License

MIT