chunking-streams

node-chunking-streams
=====================


A set of Node.js streams to process data in chunks

1. LineCounter
1. SeparatorChunker
1. SizeChunker
1. GzipChunker
1. S3MultipartUploader

To intstall with NPM

``
npm install chunking-streams
`

To use with Node.JS

`javascript

var chunkingStreams = require('chunking-streams');

var LineCounter = chunkingStreams.LineCounter;
var SeparatorChunker = chunkingStreams.SeparatorChunker;
var SizeChunker = chunkingStreams.SizeChunker;

// ad so on...
`


LineCounter
-----------

Simple TransformStream which counts lines (\n is a separator) and emit data chunks contains exactly specified number
of them.

$3

`javascript
new LineCounter({
numLines: 1, // number of lines in a single output chunk. 1 is default
flushTail: false // on stream end, flush or not remaining buffer. false is default
});
`

SeparatorChunker
----------------


Split incoming data into chunks based on specified separator. After each separator found data chunk is emitted.
By default separator sequence is set to \n, so it is equals to LineCounter with numLines: 1

$3

`javascript
new SeparatorChunker({
separator: '\n', // separator sequence
flushTail: false // on stream end, flush or not remaining buffer. false is default
});
`

SizeChunker
-----------

Split streams into chunks having exactly specified number of bytes. It is object mode stream!
Each data chunk is an object with the following fields:

- id: number of chunk (starts from 0)
- data: Buffer with data

SizeChunker has 2 additional events:

- chunkStart: emitted on each chunk start.
- chunkEnd: emitted on each chunk finish.

Both event handlers must accept two arguments:

- id: number of chunk
- done: callback function, must be called then processing is completed

If some tail data is not fit fully into specified chunk size, it can be emitted at the end if flushTail flag is set.

$3

`javascript
new SizeChunker({
chunkSize: 1024 // must be a number greater than zero.
flushTail: true // flush or not remainder of an incoming stream. Defaults to false
});
`

$3


`javascript
var input = fs.createReadStream('./input'),
chunker = new SizeChunker({
chunkSize: 1024
}),
output;

chunker.on('chunkStart', function(id, done) {
output = fs.createWriteStream('./output-' + id);
done();
});

chunker.on('chunkEnd', function(id, done) {
output.end();
done();
});

chunker.on('data', function(chunk) {
output.write(chunk.data);
});

input.pipe(chunker);
``

$3

INCOMPLETE