https://github.com/stdlib-js/streams-node-split
Transform stream which splits streamed data.
https://github.com/stdlib-js/streams-node-split
crlf delimited delimiter duplex javascript lf newline node node-js nodejs readable stdlib stream streams transform util utilities utility utils writable
Last synced: about 2 months ago
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Transform stream which splits streamed data.
- Host: GitHub
- URL: https://github.com/stdlib-js/streams-node-split
- Owner: stdlib-js
- License: apache-2.0
- Created: 2021-06-15T17:46:23.000Z (almost 5 years ago)
- Default Branch: main
- Last Pushed: 2026-03-02T05:10:43.000Z (3 months ago)
- Last Synced: 2026-03-02T06:16:24.747Z (3 months ago)
- Topics: crlf, delimited, delimiter, duplex, javascript, lf, newline, node, node-js, nodejs, readable, stdlib, stream, streams, transform, util, utilities, utility, utils, writable
- Language: JavaScript
- Homepage: https://github.com/stdlib-js/stdlib
- Size: 2.16 MB
- Stars: 2
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
- Citation: CITATION.cff
- Security: SECURITY.md
- Notice: NOTICE
Awesome Lists containing this project
README
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The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.
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# Split Stream
[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url]
> [Transform stream][transform-stream] which splits streamed data.
## Installation
```bash
npm install @stdlib/streams-node-split
```
Alternatively,
- To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).
- If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).
- For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).
The [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.
To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.
## Usage
```javascript
var splitStream = require( '@stdlib/streams-node-split' );
```
#### splitStream( \[options] )
Creates a [transform stream][transform-stream] which splits streamed data.
```javascript
var stdout = require( '@stdlib/streams-node-stdout' );
var stream = splitStream();
stream.pipe( stdout );
stream.write( '1\n2\n3' );
stream.end();
// prints: 1 => 2 => 3
```
The function accepts the following `options`:
- **sep**: separator used to split streamed data. Similar to [`String#split`][string-split], a separator may be either a [regular expression][regexp] or a `string`. Default: `/\r?\n/`.
- **objectMode**: specifies whether a [stream][stream] should operate in [objectMode][object-mode]. Default: `false`.
- **encoding**: specifies how `Buffer` objects should be decoded to `strings`. Default: `null`.
- **highWaterMark**: specifies the `Buffer` level at which `write()` calls start returning `false`.
- **allowHalfOpen**: specifies whether a [stream][stream] should remain open even if one side ends. Default: `false`.
- **writableObjectMode**: specifies whether the writable side should be in [objectMode][object-mode]. Default: `false`.
To set [stream][stream] `options`,
```javascript
var opts = {
'sep': ',',
'objectMode': true,
'encoding': 'utf8',
'highWaterMark': 64,
'allowHalfOpen': true,
'writableObjectMode': false // overridden by `objectMode` option when `objectMode=true`
};
var stream = splitStream( opts );
```
#### splitStream.factory( \[options] )
Returns a `function` for creating [streams][transform-stream] which are identically configured according to provided `options`.
```javascript
var opts = {
'sep': '\t',
'objectMode': true,
'encoding': 'utf8',
'highWaterMark': 64
};
var factory = splitStream.factory( opts );
// Create 10 identically configured streams...
var streams = [];
var i;
for ( i = 0; i < 10; i++ ) {
streams.push( factory() );
}
```
This method accepts the same `options` as [`splitStream()`](#split-stream).
#### splitStream.objectMode( \[options] )
This method is a convenience function to create [streams][stream] which always operate in [objectMode][object-mode].
```javascript
var stdout = require( '@stdlib/streams-node-stdout' );
var stream = splitStream.objectMode({
'sep': ','
});
stream.pipe( stdout );
stream.write( 'a,b,c' );
stream.end();
// prints: a => b => c
```
This method accepts the same `options` as [`splitStream()`](#split-stream); however, the method will **always** override the [objectMode][object-mode] option in `options`.
## Notes
- Similar to [`String#split`][string-split], a separator which is a [regular expression][regexp] containing a matching group will result in the separator being retained in the output stream.
```javascript
var stdout = require( '@stdlib/streams-node-stdout' );
var stream = splitStream({
'sep': /(,)/
});
stream.pipe( stdout );
stream.write( '1,2,3' );
stream.end();
// prints: 1 => , => 2 => , => 3
```
## Examples
```javascript
var transformStream = require( '@stdlib/streams-node-transform' );
var stdout = require( '@stdlib/streams-node-stdout' );
var splitStream = require( '@stdlib/streams-node-split' );
function append( chunk, enc, clbk ) {
clbk( null, chunk.toString()+'\n' );
}
var newline;
var stream;
var i;
// Create a split stream to split tab delimited data:
stream = splitStream({
'sep': /\t/
});
// Create a transform stream to make newline delimited data...
newline = transformStream({
'transform': append,
'objectMode': true
});
// Create a stream pipeline:
stream
.pipe( newline )
.pipe( stdout );
// Write data to the pipeline...
for ( i = 0; i < 10; i++ ) {
stream.write( i+'\t', 'utf8' );
}
stream.end();
```
* * *
## See Also
- [`@stdlib/streams-node/join`][@stdlib/streams/node/join]: transform stream which joins streamed data.
* * *
## Notice
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
#### Community
[![Chat][chat-image]][chat-url]
---
## License
See [LICENSE][stdlib-license].
## Copyright
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
[npm-image]: http://img.shields.io/npm/v/@stdlib/streams-node-split.svg
[npm-url]: https://npmjs.org/package/@stdlib/streams-node-split
[test-image]: https://github.com/stdlib-js/streams-node-split/actions/workflows/test.yml/badge.svg?branch=main
[test-url]: https://github.com/stdlib-js/streams-node-split/actions/workflows/test.yml?query=branch:main
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/streams-node-split/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/streams-node-split?branch=main
[chat-image]: https://img.shields.io/badge/zulip-join_chat-brightgreen.svg
[chat-url]: https://stdlib.zulipchat.com
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/streams-node-split/tree/deno
[deno-readme]: https://github.com/stdlib-js/streams-node-split/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/streams-node-split/tree/umd
[umd-readme]: https://github.com/stdlib-js/streams-node-split/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/streams-node-split/tree/esm
[esm-readme]: https://github.com/stdlib-js/streams-node-split/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/streams-node-split/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/streams-node-split/main/LICENSE
[stream]: https://nodejs.org/api/stream.html
[transform-stream]: https://nodejs.org/api/stream.html
[object-mode]: https://nodejs.org/api/stream.html#stream_object_mode
[string-split]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split
[regexp]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions
[@stdlib/streams/node/join]: https://github.com/stdlib-js/streams-node-join