stream-bouncer

Create a queue of streams and have the bouncer make sure they stay in line!

Example

var fs = require('fs');
var StreamBouncer = require('stream-bouncer');

var bouncer = new StreamBouncer({
  streamsPerTick: 1,
  poll: 1000
});

bouncer.on('error', function(err) {
  console.error(err);
});

var counter = 1;

bouncer.on('close', function(str) {
  console.log('stream finished', str.path);
});

bouncer.on('count', function(count) {
  console.log([count, 'streams remaining'].join(' '));
});

for (var i = 0; i < 10; i++) {
  bouncer.push({
    source: fs.createReadStream(['/Users/gabrieltesta/Downloads/sync/', i, '.mp3'].join('')),
    middle: i % 2 == 0 ? zlib.createGzip() : undefined,
    destination: fs.createWriteStream(['/Users/gabrieltesta/Downloads/slave/', i*counter, '.mp3'].join('')),
  });
}

Details

A stream module that allows you to enqueue a bunch of streams without worrying about defering the piping. Just queue up as many streams as you want and let the module take care of the piping for you!

Methods

var StreamBouncer = require('stream-bouncer');

var bouncer = new StreamBouncer();

Create a new instance of a bouncer.

Use it

bouncer.push({
  source: readStream,
  middle: someStream, //middle isn't required
  destination: writeStream
});

#Events

bouncer.on('start', function(str){...});

Fires when one of the streams in the queue starts, passes a stream to the callback. str is the stream.source object.

bouncer.on('close', function(str){...});

fires when one of the streams in the queue finishes, passes a stream to the callback. str is the stream.source object.

bouncer.on('count', function(count){...});

fires when the number of streams in the queue changes, passes a number to the callback.

bouncer.on('error', function(err){...});

forwards an error object to the cb.

Options

var defaultOptions  = {
  streamsPerTick: 5, //how many simultaneous streams to process per tick
  poll: 250, //how long to wait before process {count} # of streams in ms
  throttle: false, // throttle the streams speed.
  speed: null //only required if throttling is active
}

###example of overloading options

var bouncer = new StreamBouncer({
  streamsPerTick: 1,
  poll: 1000,
  throttle: true,
  speed: 2 * 1024 * 1024 //max 2 MB/s tranfer
});

Install

With npm do:

npm install stream-bouncer

to get the library.

License

MIT