Nanite - Drain

A writable stream wrapper that can attach a function to drain from any readable and transform type streams that are set to objectMode: true. Handles both strings and objects. Designed for use with Nanite, supports back pressure.

Installation

To install, simply use npm:

npm install nanite-drain --save

Usage

The example below can be found and ran in the eg folder of the Nanite repository. It demonstrates how to use nanite-drain and nanite-fill with the nanite package. Bear in mind though that this module can be used with any readable or transform stream, not just Nanite.

'use strict'
 
// create a new instance of nanite and take a
// copy of both the fill and drain modules.
var nanite = require('nanite')(),
    fill = require('nanite-fill'),
    drain = require('nanite-drain')
 
// set up a basic handler, this should be called
// as many times as there are objects passed to fill.
var handlePrint = nanite.handlerFor({cmd: 'print'})
 
// drain is a simple write stream that accepts a
// back pressure supported function.
handlePrint(drain(function (msg, done) {
  console.log('Message ' + msg.val + ' handled')
  done()
}))
 
// fill accepts an array of messages and returns
// a primed readable stream. To push the messages
// into nanite is as simple as piping fill to it.
fill([
  {cmd: 'print', val: 1},
  {cmd: 'print', val: 2},
  {cmd: 'print', val: 3},
  {cmd: 'print', val: 4},
  {cmd: 'print', val: 5}
]).pipe(nanite)

API Overview

Constructor

Requiring nanite-drain produces a builder function for creating Drain instances. Each instance of Drain maintains is it's own writeable stream which can pipe to any readable or transform stream.

 
var drain = require('nanite-drain')
 
var instanceOne = drain(function (msg, done) {
  done()
})
 
var instanceTwo = drain(function (msg, done) {
  done()
})
 

FAQ

Can I use Through2 or other stream do-da's with Nanite - Drain ?

Yes! Nanite - Drain itself is a simple writable stream and as such can be piped to any standard readable or transform stream. Most if not all modules based on standard streams should be compatible.

Does it work in browsers ?

Yes! Simply require as normal and let Webpack, Browserify, or other do their magic.

Contributing

Nanite - Drain is an open project and encourages participation. If you feel you can help in any way, be it with examples, extra testing, or new features please be our guest.

See our Contribution Guide for information on obtaining the source and an overview of the tooling used.

License

Copyright Dean McDonnell 2015, Licensed under MIT.